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1
Selyukov, D. D., and N. V. Vishnyakov. "INFLUENCE OF VERTICAL CURVE ON HIGHWAY TRAFFIC SAFETY." Science & Technique 17, no. 3 (May 31, 2018): 255–60. http://dx.doi.org/10.21122/2227-1031-2018-17-3-255-260.
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The paper is devoted to a challenging problem of ensuring traffic safety on the sections of a highway vertical curve and it provides an analysis for works concerning design, lay-out and organization of a project roadway. A change in vehicle speed has been analyzed depending on the length of a curve and a maximum longitudinal slope of a project roadway. The paper presents statistical data about accidents in the Republic of Belarus for several years on the sections of curves pertaining to project roadways. Comparative analysis of difference between point marks on a parabola is given in the paper and the parabola is inscribed in the fracture of the project roadway while using two methods. The paper presents the following errors: geodetic measurements in excesses while laying out pavement, elevation points along pavement axis while making road pavement. Emergence of centrifugal force causes a change in shearing and holding forces. Excess of the shearing force on the holding one leads to spontaneous sliding in the direction of a shearing force vector. Technical solutions have been developped on the basis of systematic functional and active deterministic method. The solutions are protected by invention patents of the Republic of Belarus and they ensure safety passages of highway sections with this type of curves in a longitudinal profile. While constructing and accepting a road for operation it is necessary to control references of curve elements in the longitudinal profile according to the results of executive surveys and in case of operation it is necessary to inform a driver about a safety speed for a passage through such sections
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Xiong, Chun Bao, Mei Jiao Xiao, and Xiao Rui Shi. "Test Analysis of Groundwater Withdrawal and Land Subsidence in Tianjin Airport Project." Applied Mechanics and Materials 204-208 (October 2012): 418–24. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.418.
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The pumping tests on the hydrogeology, including single well tests, group wells tests and land subsidence analysis, were carried out for Tianjin transportation center project. The straight-line graphical method, curve fitting method, formula method and infiltration curve extrapolation method were applied to obtain the permeability coefficients and influence radius of the main aquifers, and to obtain the mutual influence between the aquifers. The results of the land subsidence observations indicate that amount of land subsidence decreases with increasing distance from the wells. And it is also found the land subsidence of a band range is obvious, and its distribution changes unregulated. It could be preliminarily inferred that this anomaly is due to the venue internal west alkali river that has been recently backfilled.
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Crispim, José, Luiz Henrique Silva, and Nazaré Rego. "Project risk management practices: the organizational maturity influence." International Journal of Managing Projects in Business 12, no. 1 (March 4, 2019): 187–210. http://dx.doi.org/10.1108/ijmpb-10-2017-0122.
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PurposeThe purpose of this paper is to identify patterns of project risk management (PRM) practices’ adoption, and provides empirical evidence concerning the importance (and key attributes) of organizational PRM maturity to the use of risk-related practices and project performance.Design/methodology/approachThe research involved two phases: interviews with five project managers, and a worldwide survey of project managers that resulted in the analysis of 865 valid questionnaire responses. Cluster analysis was used to classify PRM practices’ use, factor analysis to detect the structure of the relationship between the variables measuring PRM practices’ use and a multiple regression analysis (with canonical correlation) to further reveal the different degrees to which PRM practices and organizational maturity are associated.FindingsThe identified patterns of risk practices’ adoption indicate that different contexts of organization PRM maturity and project complexity influence practices selection. The PRM practices related with targets (e.g. time-phased budget plan) are the most used, and those related to tools and techniques (e.g. S-curve) are the least used. Additionally, the obtained results confirm that organizational PRM maturity influences risk practices’ usage, moderated by project complexity, and organizational PRM maturity influences project performance.Originality/valueEmpirical methods were used to investigate the relationship between organizational PRM maturity and a large set of PRM practices with project complexity as a moderator. Gaps in the use of PRM practices (i.e. areas where more PRM knowledge and training are needed) were identified. Finally, this work identifies the attributes of organizational maturity with implications in practices’ usage and project performance.
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Hu, Da, Yongsuo Li, Xiaoqiang Liang, Youping Wu, Sheng Zhang, and Qi Yao. "Analysis and Prediction of Pavement Settlement Caused by Jacking Construction of Ultra-Shallow Rectangular Shield Frame Bridge." Mathematical Problems in Engineering 2020 (October 28, 2020): 1–14. http://dx.doi.org/10.1155/2020/9624927.
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The primary purpose of this paper is to analyze and predict the ground settlement law of large-span rectangular shield frame bridge jacking project, to provide a reference for the optimization design and safe construction of similar projects. In this paper, combined with the jacking project of ultra-shallow buried soft soil layer rectangular shield frame bridge, through the on-site monitoring, the settlement deformation law of the longitudinal and transverse sections of the expressway pavement during the jacking construction process is discussed, and the reasons for the large settlement and rebound are analyzed. The basic laws of the road surface settlement with time are summarized. Based on the Kriging spatiotemporal prediction model, the road surface settlement is predicted. The research shows that the transverse settlement trough of the pavement caused by the rectangular shield frame bridge’s jacking construction is stable within 15 m–20 m on both sides toward the axis and symmetrical along the coordinate axis and the alignment roughly conforms to the normal distribution. The influence range of settlement trough becomes greater and greater with shield jacking, and the final settlement curve is W-shaped. After comparing the predicted curve with the measured road settlement curve, we found that the two curves are in good agreement, and the prediction result of the Kriging spatiotemporal prediction model is valid, which can reflect the process of road deformation development during the jacking process of the shield.
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Zheng, Xi Jian, Zhong Nan Wang, and Lei Ma. "Analysis of Influence Parameters of the Project Ribbed Bar Machining Quality." Applied Mechanics and Materials 328 (June 2013): 426–31. http://dx.doi.org/10.4028/www.scientific.net/amm.328.426.
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This paper presents the method of calculating roller spacing and press amount of straightening roll. based on rigid-flexible virtual prototype technology, the entities model of straightening block was established by Pro/E, then it was imported into the ADAMS environment and constraints were added to create a rigid model, the model neutral file generated by ANSYS, thereby the rigid-flexible coupling virtual prototype was established. The distance of the point in the steel-bar relative to the end in Y direction is obtained through simulation, the acceleration curve and the range of roller spacing and press amount which consist with theory and the straightness of the ribbed bar after being straightened are obtained, which are reference to the dynamic simulation of the same complicated mechanical system and the theory of steel-bar straightening.
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Huang, Qiang, Wei Ping Wang, and Hai Yan Deng. "Study on the Influence of Shallow Groundwater Source Heat Pumps on Groundwater Quality in Weifang, China." Applied Mechanics and Materials 641-642 (September 2014): 97–100. http://dx.doi.org/10.4028/www.scientific.net/amm.641-642.97.
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Selecting 4 shallow groundwater source heat pump (GSHP) projects as research objects in Weifang city of Shandong province, China, the groundwater quality in the project area was, observed and analyzed by sampling continuously. The results show that the concentrations of chloride and the total hardness are relatively stable, and there are no apparent changes; In the change curve of TDS in different kind of shallow GSHPs, the worse the sealing condition of the project, the more obvious the rising trend of TDS; The concentration of nitrate is generally on the rise, and the concentration of ammonia appears in the trend of first increased then decreased. Therefore, in the region, the shallow GSHPs are not completely free from contamination in the current technology conditions and the application should be controlled and managed strictly. The observation of shallow GSHPs still need be conducted in a long term.
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Hua, Xi. "Study on Engineering Materials with Results of the Analysis of the Influence of Foundation Pit Surrounding Buildings Settlement." Advanced Materials Research 788 (September 2013): 631–35. http://dx.doi.org/10.4028/www.scientific.net/amr.788.631.
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In this project, some engineering materials will be used, such as reinforcing bar, commercial concrete. Because the site underground water level is higher, in order to prevent the surrounding buildings and roads happens the non-uniform settlement, the settlement must be observed, using single double station observation way, each settlement will draw up the curve, and according to the settlement curve for foundation pit precipitation to the influence of the architecture around the research.
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Giessler, M., F. Gauterin, K. Wiese, and B. Wies. "Influence of Friction Heat on Tire Traction on Ice and Snow." Tire Science and Technology 38, no. 1 (March 1, 2010): 4–23. http://dx.doi.org/10.2346/1.3298679.
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Abstract The internal drum test bench of the Universität Karlsruhe (TH) allows tire performance measurements under controllable conditions. In cooperation with Continental AG a research project was initiated to focus on traction on ice and snow surfaces. The test chamber was upgraded with a cooling system, surface conditioners and a snow production system. As a major result of these experiments, a strong correlation of thermal conditions and transmittable forces has been discovered. Furthermore, a high-speed infrared camera was used to monitor the temperature increase of the tire surfaces under traction. This paper presents the developed theoretical model, which describes the time dependent temperature increase in the contact zone. Based on this model, a formula to determine the thermal limiting curve of force transmission on ice and snow was derived. The computed curves were verified through comparison with experimental data.
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Li, Ju, Chang Lin Liao, and Shi Li. "Characteristics Curve of Multicontact for CO2 Flood." Advanced Materials Research 734-737 (August 2013): 1161–64. http://dx.doi.org/10.4028/www.scientific.net/amr.734-737.1161.
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Miscible and/or near miscible CO2 flood are among the most widely used enhanced oil recovery techniques. The successful design and implementation of a miscible gas injection project is dependent upon the accurate determination of MMP[1]-[9], the pressure above which the displacement process becomes multicontact miscible. This paper presents a method to get the characteristics curve of multicontact. The curve can illustrate the character in the Miscible and/or near miscible gas injection processes, based the curve, From the change of characteristics curve of multicontact ,we can known the type of the displacement, and the influence of injection gas to the MMP.
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Sidorova, E. A., O. N. Vaganova, and A. Yu Slastenin. "Methods for determining the position of the curve in the plan and the influence of the geometry of the track on the indicators of interaction between the track and the rolling stock." VNIIZHT Scientific Journal 79, no. 6 (February 27, 2021): 365–72. http://dx.doi.org/10.21780/2223-9731-2020-79-6-365-372.
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The article substantiates the necessity of supplementing the existing estimate of the track position in the plan by the difference of adjacent bending arrows with an estimate of deviations from the fixed initial position, which ensures the constancy of the characteristics of a single-radius curve or the components of a multi-radius curve along their entire length. As a fixed initial position of the reference base (base position), it is proposed to accept the design position or the position of the track after the repair performed according to the project, and in the absence of the project, the calculated position obtained using verified programs. The question of determining the values of the deviation of the position of the curves at individual points from the base position and their ranking for different variants of recording the curves is considered. As possible options for surveying are considered Geodetic measurement methods using Cartesian and polar coordinate systems, methods of obtaining information from transformed data from sensors of track measuring cars, as well as the classical method of measuring the arrows of the bend of a curve.The article presents the results of calculating the indicators of the interaction between the track and the rolling stock (frame and horizontal transverse forces, lateral deflections of rails) when modeling the motion of a freight car along curves, the parameters of which were obtained on the basis of analysis of data from experimental sections. The calculation results are correlated with the analyzed data on the presence of deviations from the base position in the curves.
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Wang, Ya-Qiong, Wei-Kang Kong, and Zhi-Feng Wang. "Effect of Expanding a Rectangular Tunnel on Adjacent Structures." Advances in Civil Engineering 2018 (November 6, 2018): 1–13. http://dx.doi.org/10.1155/2018/1729041.
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The expansion of urban underpass has become the mainstream of development to cope with urban congestion, and the effect on adjacent existing structures during enlarging construction is also an important issue in the construction process. In order to better understand the influence of tunneling on adjacent structures, the pedestrian underpass expanding project above-crossing Xi’an Metro Line 1 was investigated. The aim was to analyze the deformation curves characteristics of adjacent structures by field observation of ground settlement, heave of existing tunnels, and settlement of piles. The results show that the ground settlement curve in the vertical direction of the underpass is similar to the shape of V, and the maximum settlement appearing in the center line of underpass is 18.7 mm. Due to the effect of existing tunnels on the ground deformation, the settlement curve in the parallel direction of the underpass is similar to the shape of M. Above-crossing tunneling would cause the existing tunnels to heave, and the heave mainly occurs in the range of −6 m to 12 m between the pedestrian tunnel face and the center line of each tunnel. The heave curve is similar to the shape of inverted U. The settlement of piles is linear with its axial stress and significantly affected by its location. The settlement curve of piles is similar to the shape of S in two dimensions. On the basis of deformation curves, this paper presents some equations to describe the shape of V, M, inverted U, and S, respectively, by the inverted Gaussian distribution curve, superimposed Gaussian distribution curve, Gaussian distribution curve, and arctangent function.
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Yang, Yu Si, Ru Dong, and Jie Gao. "The Fehleranalyse Error Analysis of Fully Characteristic Curve of Pump to Be Nominalization and Study for the Influence on Result of Hydraulic Transients Calculation." Advanced Materials Research 250-253 (May 2011): 3696–701. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.3696.
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In this paper，by transforming the fully characteristic curve of pump with eighty specific speed to be numeralization he obtained fehleranalyse error of discrete data were analyzed based on the pump similarity theory and the difference between certain assumed condition and real situation in numeralization process. Then the influence of the fehleranalyse error of numeralization method on the pressure boost caused by Pump-off water hammer was computed by a Pump-off water hammer calculation within an real engineering project. The reliability of numeric calculation method of fully characteristic curve of Pump is proved.
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Hernandez, Paul R., Patricia D. Hopkins, Krysta Masters, Lisa Holland, Betty M. Mei, Michelle Richards-Babb, Kimberly Quedado, and Natalie J. Shook. "Student Integration into STEM Careers and Culture: A Longitudinal Examination of Summer Faculty Mentors and Project Ownership." CBE—Life Sciences Education 17, no. 3 (September 2018): ar50. http://dx.doi.org/10.1187/cbe.18-02-0022.
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It is widely recognized that the United States needs to attract and retain more people in science, technology, engineering, and mathematics (STEM) careers. Intensive undergraduate research experiences (UREs) are one of the few strategies shown to improve longitudinal student interest and persistence in STEM-related career pathways; however, less is known about the underlying process linking activities to positive outcomes. The tripartite integration model of social influences (TIMSI) provides a framework for understanding the social influence processes by which students integrate into STEM careers and culture. The current study used a longitudinal design and latent growth curve modeling to examine and predict the development of scientific research career persistence intentions over the course of an intensive summer URE. The latent growth curve analysis showed that student persistence intentions declined and rebounded over the course of the summer. Furthermore, the positive impact of faculty mentor role modeling on growth trajectories was mediated through internalization of science community values. In addition, project ownership was found to buffer students from the typical trend of declining and rebounding persistence intentions. The TIMSI framework illuminates the contextual features and underlying psychological processes that link UREs to student integration into STEM careers and culture.
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Yan, Qing Hui, Han Min Xiao, Ling Hui Sun, Wei Dong Liu, and Jun Cheng Hu. "Study on the Features of Production Decline Law in Oil Manufacturing System in Wangyao Block." Applied Mechanics and Materials 252 (December 2012): 388–93. http://dx.doi.org/10.4028/www.scientific.net/amm.252.388.
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Features of production decling determines the deployment of development project in oilfield, which has heavy influence on the oil manufacturing system. Eq.(17)and (18) have shown the final results. The characteristics of oil and water percolation, presented by Figure.1, are the primary factors for decline law. Oil-water relative permeability equations of WangYao Block, in AnSai oilfield, was deducted, and the oil-water relative permeability curves were drawn according to the equations. The oil phase curve presents a change from a linear relationship to an exponential relationship with the increase of the water saturation, which means an exponential decrease and a harmonic decrease of the single well production.
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Figueredo, Aurelio José, Audrey J. Brooks, H. Stephen Leff, and Lee Sechrest. "A Meta-Analytic Approach to Growth Curve Analysis." Psychological Reports 87, no. 2 (October 2000): 441–65. http://dx.doi.org/10.2466/pr0.2000.87.2.441.
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A meta-analytic approach to growth curve analysis is described and illustrated by applying it to the evaluation of the Arizona Pilot Project, an experimental project for financing the treatment of the severely mentally ill. In this approach to longitudinal data analysis, each individual subject for which repeated measures are obtained is initially treated as a separate case study for analysis. This approach has at least two distinct advantages. First, it does not assume a balanced design (equal numbers of repeated observations) across all subjects; to accommodate a variable number of observations for each subject, individual growth curve parameters are differentially weighted by the number of repeated measures on which they are based. Second, it does not assume homogeneity of treatment effects (equal slopes) across all subjects. Individual differences in growth curve parameters representing potentially unequal developmental rates through time are explicitly modeled. A meta-analytic approach to growth curve analysis may be the optimal analytical strategy for longitudinal studies where either (1) a balanced design is not feasible or (2) an assumption of homogeneity of treatment effects across all individuals is theoretically indefensible. In our evaluation of the Arizona Pilot Project, individual growth curve parameters were obtained for each of the 13 rationally derived subscales of the New York Functional Assessment Survey, over time, by linear regression analysis. The slopes, intercepts, and residuals obtained for each individual were then subjected to meta-analytic causal modeling. Using factor analytic models and then general linear models for the latent constructs, the growth curve parameters of all individuals were systematically related to each other via common factors and predicted based on hypothesized exogenous causal factors. The same two highly correlated common factors were found for all three growth curve parameters analyzed, a general psychological factor and a general functional factor. The factor patterns were found to be nearly identical across the separate analyses of individual intercepts, slopes, and residuals. Direct effects on the unique factors of each subscale of the New York Functional Assessment Survey were tested for each growth curve parameter by including the common factors as hierarchically prior predictors in the structural model for each of the indicator variables, thus statistically controlling for any indirect effect produced on the indicator through the common factors. The exogenous predictors modeled were theoretically specified orthogonal contrasts for Method of Payment (comparing Arizona Pilot Project treatment or “capitation” to traditional or “fee-for-service” care as a control), Treatment Administration Site (comparing various locations within treatment or control groups), Pretreatment Assessment (comparing general functional level at intake as assigned by an Outside Assessment Team), and various interactions among these main effects. The intercepts, representing the initial status of individual subjects on both the two common factors and the 13 unique factors of the subscales of the New York Functional Assessment Survey, were found to vary significantly across many of the various different treatment conditions, treatment administration sites, and pretreatment functional levels. This indicated a severe threat to the validity of the originally intended design of the Arizona Pilot Project as a randomized experiment. When the systematic variations were statistically controlled by including intercepts as hierarchically prior predictors in the structural models for slopes, recasting the experiment as a nonequivalent groups design, the effects of the intercepts on the slopes were found to be both statistically significant and substantial in magnitude. Furthermore, the contrasts for Pretreatment Assessment scores also predicted statistically significant proportions of variance in both the two common factors and the 13 unique factors of the subscales of the New York Functional Assessment Survey for all three growth curve parameters, confirming an influence of the initial status of individual subjects on treatment effect. This empirical example illustrates both the mechanics and the many practical benefits of a meta-analytic approach to growth curve analysis in program evaluation.
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Liu, Yan, Kai Xu, and Meirong Wei. "A study on MEMS oscillators‘ frequency drift of temperature." MATEC Web of Conferences 189 (2018): 11002. http://dx.doi.org/10.1051/matecconf/201818911002.
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The frequency output of oscillators is subject to a series of factors, such as working temperature, humidity, shock and vibration. Most of these factors are related to the manufacturing processes and packaging techniques employed in the semiconductor industry. Among the above factors, the influence of temperature is the most direct and most significant. And the effect of temperature on the frequency output of the oscillator is also called oscillators‘ frequency drift of temperature. This project aims to study frequency drift of two types of oscillators influenced by temperature, namely Quarts oscillators and MEMS oscillators. Firstly, the report states two types of oscillators‘ strength and weakness respectively. And then, referring to some industrial standards, the report also deceives and performs a series of tests to obtain data about the behavior of oscillators in different temperature. The experimental results show that the curve of the frequency-temperature of OCXO is approximately a horizontal line. And the curve of MEMS oscillator 1 looks like a capital letter M with relative small amplitude, and the curve of MEMS oscillator 2 is close to a slowly decreasing line. While the curve of crystal oscillator is a sine curve with steep rise at the end. According to the diagram, a conclusion that MEMS oscillators‘ frequency drift of temperature is less than that of crystal oscillators can be drawn naturally.
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Marco, Y., I. Masquelier, V. Le Saux, and P. Charrier. "FAST PREDICTION OF THE WÖHLER CURVE FROM THERMAL MEASUREMENTS FOR A WIDE RANGE OF NR AND SBR COMPOUNDS." Rubber Chemistry and Technology 90, no. 3 (July 1, 2017): 487–507. http://dx.doi.org/10.5254/rct.16.83755.
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ABSTRACT In previous papers, a protocol using thermal measurements to predict the fatigue lifetime throughout an energy-based criterion afforded a very efficient prediction of the deterministic Wöhler curve with only one sample, within less than 1 day. Nevertheless, these papers investigated a limited number of materials because the fatigue campaigns required to provide a validation of this fast prediction are very demanding in time and specimens. In this study, the PROFEM project (supported by the French National Research Agency) allowed us to investigate a very wide range of materials including natural rubber (NR) and synthetic compounds (SBR). The investigation therefore considers either crystallizing (NR) or noncrystallizing (SBR) materials for several carbon black amounts (0, 20, 43, 58 phr) and types (N220, N326, N375, N550, N772). As a first step, this study presents the application of the fast prediction protocol on one compound and investigates its robustness (repeatability, influence of the N frequency, sensitivity to the graphical analysis). Then, the method is challenged on the 11 other compounds, and the comparison of the predicted fatigue curve with the Wöhler curves obtained by classical campaigns highlights a very good agreement for most of the materials.
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Huang, Shan Ming, Yu Chuan Liu, and Cheng Cheng Wang. "Stability Analysis of Sinkhole Considering Groundwater Level Fluctuation." Applied Mechanics and Materials 226-228 (November 2012): 1426–31. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.1426.
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The Method of Finite Element Method Strength Reduction is used to numerical calculate and analyse the subgrade with soil cave, by considering the influence of groundwater level fluctuation in its stability. Nondimensionalize the effect factors, and draw the stability curve to get the regression curve, then make the result regression coefficient directly to the project cases. The result shows that under the weight of the subgrade, the subgrade with soil cave is damaged by that the soil around the soil cave is sheared. The more the value of is, the larger the stability coefficient is, and the higher groundwater level is, the better the stability of the subgrade with soil cave is. With the value increases, the region of stability expands
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Zhang, Jie, Gang Wang, Haobo Jiang, Fangzheng Zhao, and Guilin Tian. "Research and Appalication of Software Defect Predictionn based on BP-Migration learning." MATEC Web of Conferences 232 (2018): 03017. http://dx.doi.org/10.1051/matecconf/201823203017.
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Software Defect Prediction has been an important part of Software engineering research since the 1970s. This technique is used to calculate and analyze the measurement and defect information of the historical software module to complete the defect prediction of the new software module. Currently, most software defect prediction model is established on the basis of the same software project data set. The training date sets used to construct the model and the test data sets used to validate the model are from the same software projects. But in practice, for those has less historical data of a software project or new projects, the defect of traditional prediction method shows lower forecast performance. For the traditional method, when the historical data is insufficient, the software defect prediction model cannot be fully studied. It is difficult to achieve high prediction accuracy. In the process of cross-project prediction, the problem that we will faced is data distribution differences. For the above problems, this paper presents a software defect prediction model based on migration learning and traditional software defect prediction model. This model uses the existing project data sets to predict software defects across projects. The main work of this article includes: 1) Data preprocessing. This section includes data feature correlation analysis, noise reduction and so on, which effectively avoids the interference of over-fitting problem and noise data on prediction results. 2) Migrate learning. This section analyzes two different but related project data sets and reduces the impact of data distribution differences. 3) Artificial neural networks. According to class imbalance problems of the data set, using artificial neural network and dynamic selection training samples reduce the influence of prediction results because of the positive and negative samples data. The data set of the Relink project and AEEEM is studied to evaluate the performance of the f-measure and the ROC curve and AUC calculation. Experiments show that the model has high predictive performance.
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Jiang, Kaiyuan, Yutong Zhang, Haibin Wu, Aili Wang, and Yuji Iwahori. "Heterogeneous Defect Prediction Based on Transfer Learning to Handle Extreme Imbalance." Applied Sciences 10, no. 1 (January 5, 2020): 396. http://dx.doi.org/10.3390/app10010396.
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Software systems are now ubiquitous and are used every day for automation purposes in personal and enterprise applications; they are also essential to many safety-critical and mission-critical systems, e.g., air traffic control systems, autonomous cars, and Supervisory Control And Data Acquisition (SCADA) systems. With the availability of massive storage capabilities, high speed Internet, and the advent of Internet of Things devices, modern software systems are growing in both size and complexity. Maintaining a high quality of such complex systems while manually keeping the error rate at a minimum is a challenge. This paper proposed a heterogeneous defect prediction method considering class extreme imbalance problem in real software datasets. In the first stage, Sampling with the Majority method (SWIM) based on Mahalanobis Distance is used to balance the dataset to reduce the influence of minority samples in defect data. Due to the negative impact of uncorrelated features on the classification algorithm, the second stage uses ensemble learning and joint similarity measurement to select the most relevant and representative features between the source project and the target project. The third phase realizes the transfer learning from the source project to the target project in the Grassmann manifold space. Our experiments, conducted using nine projects of three public domain software defect libraries and compared with four existing advanced methods to verify the effectiveness of the proposed method in this paper. The experimental results indicate that the proposed method is more accurate in terms of Area under curve (AUC).
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Fertilia, Novika Candra, and Hana Sary Ayuningtias. "CAUSE ANALYSIS OF CONTRACT AMENDMENT IN THE X DRY DAM CONSTRUCTION PROJECT IN INDONESIA." Neutron 20, no. 01 (July 31, 2020): 33–40. http://dx.doi.org/10.29138/neutron.v20i01.46.
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The government is building two dams to pursue flood capacity in Jakarta, one of which is the X Dry Dam project. There were obstacles during the construction of this project, which resulted in several changes in the form of contract amendments. The purpose of this study is to determine the most influential factors that cause contract amendments and give suggestions for that factors, so the next contract amendment can be minimized and the project can run according to the costs and time that has been set. In this study, the authors use quantitative research methods by distributing questionnaires to respondents who are staff at the contractor. Secondary data used is the S curve. This research uses 4 stages of the questionnaire by using the reliability test using SPSS version 25 software and data analysis of importance index (II). From the results of this study are the X Dry Dam Project has 5 factors that most influence the occurrence of contract amendments that are land acquisition (53.33%), severe weather conditions (52.19%), society refusal of the project (48.84%), lacking design process planning (42.12%), and schedule /estimated time by the owner is too fast (40.28%).
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Wang, You Xi, and Jun Qing Ma. "Analysis of Unconfined Compressive Strength Calculation Formula of Soil-Cement." Advanced Materials Research 243-249 (May 2011): 6869–74. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.6869.
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The soil-cement is applied in hydraulic engineering, construction engineering and highway engineering. It needs take much time and energy to do the experiment of soil-cement design, because the influence factors of soil-cement unconfined compressive strength are many. The study is based on the former experimentations, and quantitative analyzed relationships among soil-cement unconfined compressive strength, earthiness, cement mixing amount and curing time by nonlinear curve fitting. Then, rational experience formula is given in this paper. It is tested in Nantong Building foundation excavation project, and the result proves that formula is practical.
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Shen, Xiang, Da-Jun Yuan, and Da-Long Jin. "Influence of Shield Attitude Change on Shield–Soil Interaction." Applied Sciences 9, no. 9 (May 1, 2019): 1812. http://dx.doi.org/10.3390/app9091812.
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The mechanism of shield–soil interaction and multi-phase equilibrium control theory in shield tunneling process still lack sufficient understanding. Aiming at this problem, with the improved calculation method of loose earth pressure, the initial boundary problem of shield attitude calculation was solved. Based on the ground reaction curve, the shield–soil interaction was simulated by the equivalent springs, and the displacement of surrounding soil was calculated during the change of the shield attitude. Then, the theoretical method of surrounding soil load acting on the shield were obtained. In summary, the calculation method of shield attitude was obtained. This method has three main applications in engineering, namely the inversion of shield–soil interaction force, the prediction of pitch angle and the prediction of yawing angle. Finally, combined with Jinan Metro Line R2 shield tunnel project, the shield attitude was monitored in real time and compared with the theoretical value. The results show that the trend of the theoretical values of pitch angle and yawing angle were basically the same as the measured value, but the theoretical value was generally larger than the measured value. The research results can provide a useful reference for the shield attitude adjustment.
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Połoński, M. "Application Of The Work Breakdown Structure In Determining Cost Buffers In Construction Schedules." Archives of Civil Engineering 61, no. 1 (March 1, 2015): 147–61. http://dx.doi.org/10.1515/ace-2015-0010.
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AbstractThe paper presents methods of determining the location of cost buffers and corresponding contingency costs in the CPM schedule based on its work breakdown structure. Application of correctly located cost buffers with appropriately established reserve costs is justified by the common overrunning of scheduled costs in construction projects. Interpolated cost buffers (CB) as separate tasks have been combined with relevant summary tasks by the start–to–start (SS) relationship, whereas the time of their execution has been dynamically connected with the time of accomplishment of particular summary tasks using the “paste connection” option. Besides cost buffers linked with the group of tasks assigned to summary tasks, a definition of the cost buffer for the entire project (PCB) has been proposed, i.e. as one initial task of the entire project. Contingency costs corresponding to these buffers, depending on the data that the planner has at his disposal, can be determined using different methods, but always depend on the costs of all tasks protected by each buffer. The paper presents an exemplary schedule for a facility and the method of determining locations and cost for buffers CB and PCB, as well as their influence on the course of the curve illustrating the budgeted cost of work scheduled (BCWS). The proposed solution has been adjusted and presented with consideration of the possibilities created by the scheduling software MS Project, though its general assumptions may be implemented with application of other similar specialist tools.
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Guo, Jianhua, Zhangjun Dai, Shichang Li, Nadeem Muhammad, and Hui Gao. "Study on Creep Characteristics of Expansive Soil in High-Fill Channel of South-to-North Water Transfer Project." Advances in Civil Engineering 2020 (November 11, 2020): 1–19. http://dx.doi.org/10.1155/2020/8852131.
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In the Nanyang section of the midroute of the South-to-North Water Transfer Project, the expansive soil is often used as a filler for high-fill channels. After the channel is stabilized, the expansive soil undergoes creep deformation over time. Studying the creep characteristics of expansive soils in different environments is particularly important for evaluating the safe operation of high-fill channels. In the current study, the creep test of expansive soil under different moisture content and dry density was carried out. It is proposed that the slope of the fitted straight line in the compression curve of the expansive soil can be used to represent the secondary consolidation coefficient of unsaturated expansive soil, and the variation law of the secondary consolidation coefficient under different environmental factors is obtained. The modified Bjerrum calculation method considering the influence of additional load and lateral deformation yields the postexpansion soil settlement curve model to determine the control index range of the project site. Moreover, it is also observed that the secondary consolidation coefficient of unsaturated expansive soil increases with the increase of moisture content and decreases with the increase of dry density. The coefficient of secondary compression of unsaturated expansive soil is linearly related to dry density and moisture content. After the preconsolidation treatment of the expansive soil, when the load level is less than the preload, the secondary consolidation coefficient is smaller, otherwise the secondary consolidation coefficient is larger.
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Holzhütter, Hermann-Georg. "A General Measure of In Vitro Phototoxicity Derived from Pairs of Dose-Response Curves and its Use for Predicting the In Vivo Phototoxicity of Chemicals." Alternatives to Laboratory Animals 25, no. 4 (July 1997): 445–62. http://dx.doi.org/10.1177/026119299702500407.
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In pharmacology, it is common to evaluate the influence of external effectors (for example, temperature, pH, and presence of a second drug) on dose-response relations by the potency factor (PF50): [Formula: see text] where ED50 (± effector) denotes the 50% effective dose in the presence and in the absence of the effector, respectively. In this paper, the external effector is ultraviolet (UV) light, and PF50 is referred to as the photoirritancy factor (PIF). There are two parameters which limit the applicability and toxicological reliability of the PIF. Firstly, the physical properties (for example, water solubility) of the chemical tested and the constraints of the biological test system may make it difficult, or even impossible, to achieve sufficiently high doses to observe 50% of the maximal response. In such cases, no numeric value of the potency factor can be computed. Secondly, the potency factor does not take into account the absolute change in response induced by UV light, i.e. depending on the shape of the ±UV dose-response curves, the absolute change in response may be small although the PIF is large, and vice versa. This paper proposes a more general measure of phototoxicity, the mean photo effect (MPE), which can be assessed from pairs of dose-response curves, even if the 50% response level is not reached in one curve or in both. The MPE is a weighted average of PIFd values across different dose levels (d being common to both dose-response curves). The absolute response changes, ΔRd, i.e. the differences between the -UV curve and the +UV curve are used as weighting factors. The numerical computation of the MPE is based on theoretical curves obtained by fitting a mathematical model to the experimental dose-response data. Plotting PIFd and ΔRd versus the corresponding doses permits differences in the shapes of the two curves to be assessed, and possible alterations in the toxic mechanisms induced by UV light to be revealed. The variance of MPE is estimated by a bootstrap procedure. The use of the MPE is illustrated by its application to dose-response data obtained with a human keratinocyte assay of fibroblasts in the EU/COLIPA international validation project on photoirritancy.
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Malakhova, E. Y., A. M. Lamminpiya, and Yu E. Shelepin. "The influence of part of speech text structure on eye movements during natural reading." Experimental Psychology (Russia) 9, no. 4 (2016): 18–32. http://dx.doi.org/10.17759/exppsy.2016090403.
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The difficulty of lexical processing can explain substantial part of variability in fixation duration during the reading process. Factors like word length, frequency, syntactic and semantic ambiguity impact fixation time. On the other hand, there is not much understanding of how saccades parameters vary depending on the text characteristics. Here we investigate how part-of-speech text structure influences eye-movements during the natural reading process. We presented text excerpts from Russian classic literature containing overabundant quantity of verbs, nouns or adjectives to the participants and record their eye-movements during reading. Eye- tracking data was analyzed with the consideration of the individual differences in the reading behavior. We found that saccade length measured in the number of symbols covered per saccade, its duration, average velocity and curve slope differ significantly for texts with different part-of-speech content. This result can provide an evidence of the influence of higher level cognitive processes not only on fixations but also on saccadic movements. This work was supported by Russian Science Foundation (project № 14-18-02135 «Psychophysiological and neurolinguistic aspects of the recognition process, verbal and nonverbal patterns»).
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McKenzie, Jennifer A., Edward P. Weiss, Ioana A. Ghiu, Onanong Kulaputana, Dana A. Phares, Robert E. Ferrell, and James M. Hagberg. "Influence of the interleukin-6 −174 G/C gene polymorphism on exercise training-induced changes in glucose tolerance indexes." Journal of Applied Physiology 97, no. 4 (October 2004): 1338–42. http://dx.doi.org/10.1152/japplphysiol.00199.2004.
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A polymorphism in the IL-6 gene, a G-to-C substitution 176 bp upstream of the ATG translation initiation site, has been associated with diabetes prevalence and insulin resistance. Interventions including exercise training are frequently used to modify cardiovascular disease risk factors. Consequently, this project examined associations between the IL-6 −174 genotype and oral glucose tolerance test outcomes in 50- to 75-yr-old sedentary men and postmenopausal women before and after aerobic exercise training. Among the 87 individuals who started the study, 56 were retested after 6 mo of aerobic exercise training. Subject characteristics at baseline did not differ between the IL-6 genotype groups with the exception of fasting glucose, which was higher ( P = 0.02, covariates age, gender, and ethnicity) in the CC genotype group. The training-induced change in glucose area under the curve during the oral glucose tolerance test varied between the IL-6 −174 genotype groups ( P = 0.05, covariates age, gender, ethnicity, baseline glucose area under the curve, and percent body fat change) with a significant decrease occurring only in the GG genotype group. Insulin outcomes did not differ among the groups at baseline or after training. Training-induced changes in weight, percent body fat, maximal oxygen consumption, fasting glucose, and an insulin sensitivity index also changed similarly among the genotype groups. In conclusion, fasting glucose and the extent to which glucose tolerance changes with exercise training may be influenced by the IL-6 −174 gene polymorphism.
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Jing, Shu Guang, Xue Ping Gao, and Yun Peng Han. "Study on Hydraulic Characteristics of the Dragon-Raise-Head Spillway Tunnel." Advanced Materials Research 748 (August 2013): 1095–98. http://dx.doi.org/10.4028/www.scientific.net/amr.748.1095.
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This study compared the hydraulic characteristics of the Dragon-Raise-Head spillway tunnel by using a 3-D turbulence model, taking one specific spill tunnel reconstruction project as an example. In the first place, we proved the feasibility of the numerical stimulation results by the hydraulic model test of the Dragon-Head-Raise spillway tunnel comparatively. Then we comapared discharge capacity, head loss and flow state of four inlet elevations of the Dragon-Raise-Head spillway tunnel. The results showed little influence of different inlet elevations on discharge capacity, head loss and flow state under the premise of smooth curve section. The study would provide evidence for the design and optimization of the Dragon-Raise-Head spillway tunnel.
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Abualbasal, Wejdan, Emad Abu-Shanab, and Heba Al-Quraan. "Dynamic Analysis of UTAUT." International Journal of Web-Based Learning and Teaching Technologies 11, no. 3 (July 2016): 40–54. http://dx.doi.org/10.4018/ijwltt.2016070104.
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The technology adoption domain is rich with studies that utilized a cross-sectional snapshot of subjects' perceptions regarding the adoption of new technology. This research tried to implement a longitudinal study that took three measures within 4 months to estimate the influence of time and experience on students' perceptions. The study adopted a modified version of the Unified Theory of Acceptance and use of Technology (UTAUT) with effort expectancy, performance expectancy, facilitating conditions, and locus of control predicting the intention to use Microsoft Project. Results supported the UTAUT and its prediction. Also, this study fitted two types of dynamic research typologies (learning curve and equilibrium circles) to the UTAUT relationships and across time.
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Liu, Xin, Wenbin Gu, Jianqing Liu, Zhenxiong Wang, Jinglin Xu, and Tao Cao. "Investigation of the Propagation Characteristics of Underwater Shock Waves in Underwater Drilling Blasting." Shock and Vibration 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/9483756.
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During the first-stage project of the main channel of Ningbo-Zhoushan Port’s Shipu Harbor, underwater shock waves were monitored. By analyzing a typical measured pressure time history curve, the characteristics of underwater shock waves in an engineering context were obtained. We obtained a traditional exponential attenuation formula for underwater shock waves based on the measured data, simplified the model of underwater drilling blasting based on engineering practice, deduced a revised formula for underwater shock wave peak overpressure on the basis of dimensional analysis, established a linear fitting model, and obtained the undetermined coefficients of the revised formula using a linear regression analysis. In addition, the accuracies of the two formulas used to predict underwater shock wave peak overpressure and the significance order of influence and influence mechanism of factors included in the revised formula on the underwater shock wave peak overpressure were discussed.
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Shek, Daniel T. L., and Xiaoqin Zhu. "Paternal and Maternal Influence on Delinquency among Early Adolescents in Hong Kong." International Journal of Environmental Research and Public Health 16, no. 8 (April 14, 2019): 1338. http://dx.doi.org/10.3390/ijerph16081338.
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Objective: The aim was to examine the effects of parental behaviors and the parent-child relationship on delinquency levels as well as growth rates among early adolescents, and to explore the cross-sectional and longitudinal influence of fathers and mothers. Method: The study used and analyzed data collected at Waves 1–3 (N = 2669, age 12.56 ± 0.71 years at Wave 1) in a six-year research project. Results: While both parents’ behavioral control significantly predicted a lower initial level of delinquency, only higher behavioral control of fathers predicted a fast increase in delinquency. In contrast, parental psychological control did not serve as significant predictors in the individual growth curve model. Besides, relationships of father-child and mother-child dyads negatively predicted the initial level of delinquency but not the rate of change in adolescent delinquency. When all factors were investigated simultaneously, fathers’ behavioral control and the relationship between mother and child were robust cross-sectional predictors, whereas only the latter was a stable longitudinal predictor of adolescent delinquency. Conclusions: Parenting and the parent-child relationship are predictors of adolescent delinquency. It is necessary to differentiate between: (1) adolescent delinquency level and its change rate over time; (2) different aspects of parent-child dyadic factors; and (3) paternal and maternal factors.
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Yi, Chin-Chun, Chyi-In Wu, Ying-Hwa Chang, and Ming-Yi Chang. "The Psychological Well-Being of Taiwanese Youth." International Sociology 24, no. 3 (April 28, 2009): 397–429. http://dx.doi.org/10.1177/0268580909102914.
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This study examines the growth trajectory of the psychological well-being of Taiwanese adolescents from early to late adolescence. Under the competitive educational system in Taiwan, family and school context are two major loci accounting for the developmental outcome. Data are taken from the Taiwan Youth Project, which is a longitudinal panel study of 2696 students since the year 2000. The study uses individual depressive symptoms as the dependent variable. Family cohesion, family educational strategy as well as classroom effects at school are chosen to indicate the potential contextual influence. Using the latent growth curve method, the analysis confirms that family and school factors do produce different effects over time. Family context is salient at the initial status, but not for subsequent development. Class cohesion as well as adolescents' perceptions of unfairness by teachers determine the depressive level, the linear slope and the non-linear quadratic growth curve. In other words, once the adolescent gets used to junior high school, the school context tends to exert more pronounced effects. Further analysis on gender comparisons indicates that selective family and school effects are more pronounced among females, with a greater degree of depressive symptoms over time. The article concludes that while family and school have different impacts on the growth curve of individual depressive symptoms, the school context exerts salient effects over an adolescent's life course.
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Di Giulio, Giuseppe, Alexandros Savvaidis, Matthias Ohrnberger, Marc Wathelet, Cecile Cornou, Brigitte Knapmeyer-Endrun, Florence Renalier, Nikos Theodoulidis, and Pierre-Yves Bard. "Exploring the model space and ranking a best class of models in surface-wave dispersion inversion: Application at European strong-motion sites." GEOPHYSICS 77, no. 3 (May 1, 2012): B147—B166. http://dx.doi.org/10.1190/geo2011-0116.1.
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The inversion of surface-wave dispersion curve to derive shear-wave velocity profile is a very delicate process dealing with a nonunique problem, which is strongly dependent on the model space parameterization. When independent and reliable information is not available, the selection of most representative models within the ensemble produced by the inversion is often difficult. We implemented a strategy in the inversion of dispersion curves able to investigate the influence of the parameterization of the model space and to select a “best” class of models. We analyzed surface-wave dispersion curves measured at 14 European strong-motion sites within the NERIES EC-Project. We focused on the inversion task exploring the model space by means of four distinct parameterization classes composed of layers progressively added over a half-space. The classes differ in the definition of the shear-wave velocity profile; we considered models with uniform velocity as well as models with increasing velocity with depth. At each site and for each model parameterization, we performed an extensive surface-wave inversion (200,100 models for five seeds) using the conditional neighborhood algorithm. We addressed the model evaluation following the corrected Akaike’s information criterion (AICc) that combines the concept of misfit to the number of degrees of freedom of the system. The misfit was computed as least-squares estimation between theoretical and observed dispersion curve. The model complexity was accounted in a penalty term by AICc. By applying such inversion strategy on 14 strong-motion sites, we found that the best parameterization of the model space is mostly three to four layers over a half-space; where the shear-wave velocity of the uppermost layers can follow uniform or power-law dependence with depth. The shear-wave velocity profiles derived by inversion agree with shear-wave velocity profiles provided by borehole surveys at approximately 80% of the sites.
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Sze, Tat-Ming, Sieh-Hwa Lin, Pei-Jung Hsieh, and I.-Jung Chen. "Sex Differences in the Development of Perceived Family Cohesion and Depressive Symptoms in Taiwanese Adolescents." Psychological Reports 113, no. 1 (August 2013): 54–72. http://dx.doi.org/10.2466/10.02.pr0.113x18z2.
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This study investigates the progression of family cohesion perceptions and depressive symptoms during the character development stage in adolescents. Data were used from the Taiwan Youth Project. The final sample comprised 2,690 adolescents with 1,312 girls (48.8%; M age = 13.0 yr., SD = 0.5). Latent curve growth analysis was employed to explore these developments. Seventh-grade girls reported greater family cohesion and more depressive symptoms than boys, and boys reported greater growth in family cohesion than girls. However, progression of depressive symptoms was not associated with the child's sex. Higher perceived family cohesion in Grade 7 correlated with less increase of depressive symptoms from Grades 9 to 11. The long-term positive influence of family cohesion on depressive symptoms is discussed.
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Yang, Teng, Jiaqi Zhang, Xiao Zhang, Qingsong Zhang, and Zhanchao Yin. "Layered Grouting Technology Based on a Comprehensive Water-to-Cement Ratio for the Overlying Loess Stratum of Urban Shallow Tunnels." Advances in Civil Engineering 2020 (June 16, 2020): 1–13. http://dx.doi.org/10.1155/2020/2904789.
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Different from sand and clay, loess has special engineering properties; hence, existing soil grouting theories are not suitable for the disaster treatment of shallow loess tunnels. In this study, a fine grouting reinforcement test system was developed, and the Yuhan Road tunnel overlying loess was used as the injection medium. An orthogonal test based on slurry dry density, moisture content, water-to-cement ratio, and grouting pressure was conducted. Results revealed that the loess samples have high integrity after grouting, and the cohesion and compressive strength improved significantly. The stress-strain curve showed that the strengthened samples have greater ultimate and residual strengths than samples before grouting. Through a range analysis, it was determined that water-to-cement ratio and moisture content are the main factors affecting loess cohesion and compressive strength. Therefore, a comprehensive test of the water-to-cement ratio and moisture content as a single variable was conducted. It was found that their influence on loess cohesion and compressive strength is not a single linear relationship but a combined balance. To characterize the joint effect of water in loess and in slurry on reinforcement, the concept of a comprehensive water-to-cement ratio is proposed, and the cohesion and compressive strength curves with respect to this ratio were drawn. An optimal comprehensive water-to-cement ratio, which corresponds to the maximum cohesion or compressive strength, was found. Based on this ratio, we further propose a method to calculate the water-to-cement ratio of slurry and suitable grouting amount for the Yuhan Road tunnel reinforcement project, in which all solution parameters can be measured via field tests. In the project, a surface layered grouting scheme, based on the optimal comprehensive water-to-cement ratio, was designed. After grouting, loess strength was improved significantly, permeability was reduced greatly, and the overall reinforcement effect was suitable; these results provide a reference for similar projects.
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Gaffney, Michael, Jenny Munro, Ben Inns, Damian Morgan-Hudson, Kymberley Kennedy, Lisa Nyman, and Marina Buckley. "Young people’s participation in service evaluation." Aotearoa New Zealand Social Work 25, no. 4 (May 15, 2016): 62–70. http://dx.doi.org/10.11157/anzswj-vol25iss4id64.
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The Otago Youth Wellness Trust is a charitable organisation that has been operating for 15 years in Dunedin, New Zealand. It decided to evaluate the wraparound service it provided to young people in the community. The young people are referred by other agencies, including schools, and are usually deemed to be in need of significant support. In this article, members of a Youth Advisory Group (YAG), describe the experience of being involved in this service evaluation project. The YAG was made up of a small number of ‘service users’ who developed methods for engaging young people as evaluation participants. Overall we reported positive experiences, but there was a steep learning curve for all of us to navigate the evaluation process. This article demonstrates that it is possible for young people to have a significant influence in service evaluation.
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Shen, Xi Zhong, Jin Xia Zhang, and Min Zhang. "Research on Un-Linear Deformation Characteristics of Unsaturated Clay with General Triaxial Test." Advanced Materials Research 243-249 (May 2011): 3117–22. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.3117.
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Difficult in soil-water characteristic curve achieved, existence of non-uniqueness and indistinct in influence of unlinear deformation characteristics of soil about density and water content, deformation characteristics of unsaturated soil were studied difficultly with general triaxial test, thus direct application of unlinear Duncan-Chang model in unsaturated soil was restricted. General triaxial tests with combined dry density and water content are carried out, changing rules of parameters of Duncan-Chang model are summarized, mathematical functions between dry density, saturation and parameters of the model are established. Analysis shows that deformation characteristics of unsaturated clay are influenced obviously by saturation and dry density. Among them, the larger the saturation, the higher strain becomes under the condition of the same dry density and main stress difference, and the less the dry density, the higher strain becomes under the condition of the same saturation and main stress difference. Moreover, the main parameters of Duncan-Chang model keep close correction with dry density and saturation, and the both mutual effect can be expressed by multiplication. This shows that mechanical characteristics of unsaturated soil can be studied with general triaxial test, thus it will be used easily in project.
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Osborne*, Dennis, Douglas C. Sanders, and Donn R. Ward. "Fresh Produce Food Safety Training Program and Curriculum Development for the Southeast." HortScience 39, no. 4 (July 2004): 830D—831. http://dx.doi.org/10.21273/hortsci.39.4.830d.
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This project directly addresses national food safety “priority issues”. Project design incorporates food safety and food chain security as focal points of educational efforts, then initiates practical, producer-level research, teaching, and extension whereby food handling and safety issues are addressed in a systems context. The overall Project goals are (1) to deliver information about Fresh Produce Food Safety (“FPFS”) programs and principles defined in the FDA Guide to fresh fruit and vegetable handlers in the Southeastern United States, (2) to provide hands-on individual state assistance with FPFS program implementation, and (3) to determine the influence of packing line procedures on the survival of foodborne pathogens. Part of the education envisioned under the new grant is introducing the concepts of recall and traceback. These concepts, proposed for incorporation into a new Country of Origin Labeling (COOL) act being discussed for adoption, possibly in 2006, essentially allows for the traceback of food to its point of origin. Osborne and others published a new protocol last month as “Model Recall Program for the Fresh Produce Industry” and want to help growers stay ahead of the curve on these issues. As a consequence of this project, the region's commercial fresh fruit and vegetable handlers will acquire the knowledge and skills necessary to establish effective GAPs programs. Developing new GAPs programs to fit the specific needs of the packing and chain store operations in the Southeastern United States can significantly reduce the possibility of illness originating from Southeastern fresh fruit and vegetables. Delivering such programs will serve as a valuable training tool for fresh produce industries nationwide.
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Wei, Zhengde, and Yanpeng Zhu. "A Theoretical Calculation Method of Ground Settlement Based on a Groundwater Seepage and Drainage Model in Tunnel Engineering." Sustainability 13, no. 5 (March 3, 2021): 2733. http://dx.doi.org/10.3390/su13052733.
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Seepage is ubiquitous during tunneling in areas with high groundwater tables. The ground settlement trough on a single tunnel is well described by Peck’s formula, but it cannot reflect the settlement caused by seepage. In this paper, assuming that the groundwater inside and outside the tunnel is a one-dimensional steady-state seepage condition, the groundwater seepage and drainage model of the tunnel was established. Based on the model and the principle of groundwater dynamics, the seepage flow calculation formula was derived, and the dewatering funnel curve equation of the groundwater level surface of a tunnel aquifer was obtained. A case study of a tunnel project in Gansu Province was carried out, and the influence of seepage on the effective stress of the stratum around the tunnel and the calculation of ground settlement caused by seepage were analyzed. The results show that seepage makes the effective stress of the upper soil layer of the tunnel increase, which leads to an increase in ground deformation; when the groundwater level of the tunnel is greatly lowered, the seepage has a significant influence on the vertical deformation of the stratum.
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Ge, Dangke, Haiying Cheng, Mingjun Cai, Yang Zhang, and Peng Dong. "A New Predictive Method for CO2-Oil Minimum Miscibility Pressure." Geofluids 2021 (January 4, 2021): 1–8. http://dx.doi.org/10.1155/2021/8868592.
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Gas injection processes are among the effective methods for enhanced oil recovery. Miscible and/or near miscible gas injection processes are among the most widely used enhanced oil recovery techniques. The successful design and implementation of a miscible gas injection project are dependent upon the accurate determination of minimum miscibility pressure (MMP), the pressure above which the displacement process becomes multiple-contact miscible. This paper presents a method to get the characteristic curve of multiple-contact. The curve can illustrate the character in the miscible and/or near miscible gas injection processes. Based on the curve, we suggest a new model to make an accurate prediction for CO2-oil MMP. Unlike the method of characteristic (MOC) theory and the mixing-cell method, which have to find the key tie lines, our method removes the need to locate the key tie lines that in many cases is hard to find a unique set. Moreover, unlike the traditional correlation, our method considers the influence of multiple-contact. The new model combines the multiple-contact process with the main factors (reservoir temperature, oil composition) affecting CO2-oil MMP. This makes it is more practical than the MOC and mixing-cell method, and more accurate than traditional correlation. The method proposed in this paper is used to predict CO2-oil MMP of 5 samples of crude oil in China. The samples come from different oil fields, and the injected gas is pure CO2. The prediction results show that, compared with the slim-tube experiment method, the prediction error of this method for CO2-oil MMP is within 2%.
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Luo, Yanbin, Jianxun Chen, Bao Liu, Lijun Chen, and Jiangtao Xie. "Analysis of Pipe-Roof in Tunnel Exiting Portal by the Foundation Elastic Model." Mathematical Problems in Engineering 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/9387628.
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The Pasternak double-parameter elastic foundation model of pipe-roof during the construction of tunnel exits is first established. Based on the portal project of Hanjiashan highway tunnel, an inclinometer is adopted to measure the settlement deformation of a pipe-roof and demonstrates the deformation law in tunnel exiting portals. The formulas for calculating the deflection and internal forces are derived to analyze the deformation of the pipe-roof in each excavation stage, and the results are compared with field monitoring data. Finally, the influences of excavation height, excavation footage, and stiffness of the pipe-roof on the support effect are investigated. Analysis indicates that the longitudinal settlement curve shows a groove distribution, which can be divided into five stages: micro, rapid, continuous, resilience, and stable deformation. Moreover, the subsidence rate reaches its maximum at the tunnel face. The influence of tunnel excavation on the deformation mainly has a range of 1.5 times the excavation height. To control the deflection of the pipe-roof, excavation height should be controlled in the range of 3.5 m, excavation footage should be controlled in the range of 1–1.4 m, and the diameter and thickness of the selected pipe-roof should be in the ranges of 89–159 mm and 5–8 mm, respectively.
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Zheng, Yuchao, Jianyong Lei, Fei Wang, Liang Xiang, Jianfeng Yang, and Qingshuai Xue. "Investigation on Dewatering of a Deep Shaft in Strong Permeable Sandy Pebble Strata on the Bank of the Yellow River." Geofluids 2021 (September 24, 2021): 1–15. http://dx.doi.org/10.1155/2021/9994477.
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This paper reports the dewatering scheme of a deep excavation in sandy pebble strata. The excavation is in high permeability strata and is close to the Yellow River, making the dewatering difficult during construction. At present, few researchers have specially studied the dewatering scheme of deep excavations in strong permeable strata near the water resource. Field pumping test was conducted before the excavation activity, and the permeability coefficient of the strata was obtained by reverse analysis. According to the characteristics of the project, the dewatering scheme of “ waterproof curtain + base grouting + pumping ” was proposed. The influence of vertical waterproof curtain and base grouting on dewatering was analyzed by numerical simulation. In the construction process, the field water table and ground settlement were measured. The results show that (1) the groundwater table versus permeability coefficient curve shows three different stages and (2) the dewatering scheme of “ waterproof curtain + base grouting + pumping ” is effective for deep excavation in strong permeable strata.
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Zhang, Liguo, Dong Wang, and Jiaxing Dong. "Assessment of the Excavation Damaged Zones in the Surrounding Rock of an Underground Powerhouse under High In Situ Stress Using an Acoustic Velocity Detecting Method." Advances in Civil Engineering 2020 (July 4, 2020): 1–13. http://dx.doi.org/10.1155/2020/7297260.
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Excavation damaged zones (EDZs) in deeply buried underground powerhouse have become major obstacles to design and support, which potentially threaten safety and stability and increase construction and support costs. In this study, investigations of the EDZs were performed by applying an acoustic velocity detecting method in Houziyan hydropower project, southwest of China. A total of 38 testing boreholes distributed in high sidewalls of the main powerhouse were carried out, and corresponding 153 curves were obtained and analyzed. Then, EDZs were divided into highly damaged zone (HDZ), slightly damaged zone (SDZ), and excavation influence zone (EIZ), respectively. Furthermore, we classified the wave velocity curves into four categories: type I, type II, type III, and type IV. EDZs were qualitatively assessed based on the curve categories; in addition, we used a qualitative assessment method, which mainly involved an index of damage degree named D. The assessment results show that HDZ, but not SDZ, was significantly asymmetrically distributed in the upstream (average depth of 4.1 m) and downstream (average depth of 7.5 m) high sidewalls; in partial areas, depth of HDZ exceeded the length of designed rock bolts, which indicates that rock bolts cannot restrain crack development and EDZs evolution. Generally, EDZs distribution was consistent with deformation and failure phenomena distribution; compared to the field failure phenomena, the assessment results were reliable and reasonable. Finally, EDZs formation mechanism was discussed, and it can be concluded that the relatively large intermediate principal stresses σ2 were a critical driving factor of the EDZs evolution.
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Ma, Tianzhong, Yanpeng Zhu, and Xiaohui Yang. "Calculation of Bearing Capacity and Deformation of Composite Pile Foundation with Long and Short Piles in Loess Areas." Advances in Civil Engineering 2020 (October 20, 2020): 1–10. http://dx.doi.org/10.1155/2020/8829779.
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In order to calculate the bearing capacity and settlement deformation of composite pile foundations with long and short piles in collapsible loess areas, the theoretical approximate solution was used to obtain the location of the neutral point of single piles. Additionally, based on the equation to calculate the bearing capacity of multielement composite foundations, a method considering the negative frictional resistance was proposed for calculating the bearing capacity of composite pile foundations with long and short piles. Based on the shear displacement method and the principle of deformation control, an equation to calculate the displacement and deformation of a composite pile foundation was presented. A model test with different operating conditions, i.e., a single pile, four piles, and eight piles, was designed to verify the proposed calculation methods. The results show that the location of the neutral point has a significant influence on the single-pile negative frictional resistance, and the neutral point ratio of the calculation meets the value range of the practical project. When the load at the top of the pile is relatively small, the experimental curve is consistent with the theoretical calculation curve, whereas when the load is comparatively large, the theoretically calculated displacement increase at the top of the pile is greater than the measured one. Under the premise that the theoretical calculation is in good agreement with the results, the theoretical value is larger than the actual value. And it contributes to strengthening engineering safety.
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Makaske, B., and W. Z. Hoek. "Reply to the comment by M.P. Hijma & K.M. Cohen on the paper by Van de Plassche et al. (2010)." Netherlands Journal of Geosciences - Geologie en Mijnbouw 90, no. 1 (August 2011): 55–57. http://dx.doi.org/10.1017/s0016774600000676.
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First of all, we want to stress that this reply to the comment by Hijma & Cohen on the paper by Van de Plassche et al. (2010) reflects our personal view and not necessarily the opinion of the first author of the paper under discussion, Orson van de Plassche. After a long career dedicated to sea-level research, Orson passed away on May 4, 2009, and left us with the Vlaardingen data set and his explicit wish to publish this material, which ultimately led to the Van de Plassche et al. (2010) paper. In the present paper we will: (1) give some background information on the Vlaardingen data set and the special circumstances under which the Van de Plassche et al. (2010) paper was written; (2) reply to the comment on the construction of our revised mean sea-level curve (MSL-R2); (3) reply to the comment on our suggestion that the palaeoriver-gradient might influence sea-level jump magnitude calculations.The paper by Van de Plassche et al. (2010) is primarily based on the Vlaardingen data set that was collected by Orson van de Plassche in the mid-1980s, in a sequel to his PhD project (Van de Plassche, 1982). Soon after the start of the Vlaardingen project Orson became busily occupied with sea-level research in North America, leaving the Vlaardingen data set virtually unpublished (some data were published in Van de Plassche (1995)).
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Liu, Hongbo, and Hanho Kim. "Ecological Footprint, Foreign Direct Investment, and Gross Domestic Production: Evidence of Belt & Road Initiative Countries." Sustainability 10, no. 10 (September 30, 2018): 3527. http://dx.doi.org/10.3390/su10103527.
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This research is employed to examine the environmental issues embedded in Belt & Road Initiative (BRI), to be more specific: testify which of these hypotheses: Pollution Havens Hypothesis, Pollution Halo Hypothesis, Environmental Kuznets Curve is in accordance with the current development condition of BRI counties; whether there exists a bidirectional relationship among Ecological Footprint, Gross Domestic Production, Foreign Direct Investment (FDI) in Belt & Road Initiative countries. In this paper, Panel Vector Autoregression is utilized to analyze a dataset of 44-member countries in this initiative, ranges from 1990 to 2016, to empirically testify the environmental evaluation of this project. Results are analyzed on both long-run and short-run cases through Orthogonalized Impulse-Response Functions (IRF). This research displays a great heterogeneity among different target variables, FDI as a main variable of interest does not expose a bidirectional relationship with Ecological Footprint, only Ecological Footprint demonstrates robust influence on FDI. In addition, Pollution Havens Hypothesis is certified to be true for FDI and GDP among Belt & Road Initiative member countries.
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Peng, X., R. Horn, D. Deery, M. B. Kirkham, and J. Blackwell. "Influence of soil structure on the shrinkage behaviour of a soil irrigated with saline - sodic water." Soil Research 43, no. 4 (2005): 555. http://dx.doi.org/10.1071/sr04116.
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Soil structural properties of swelling/shrinking soils play an important role in assessing hydraulic properties. However, the effect of shrinkage/swelling processes on structure formation and strength especially in saline–sodic soils, such as a Typic Chromexert, has not yet been clarified. In this study, we investigate the changes in the shrinkage pattern after applying saline sewage water and use a 3-parameter sigmoidal curve model to fit its shrinkage data. Our aims were to determine the overall effect of sewage water application on soil structure and shrinkage processes after applying saline–sodic water and to evaluate soil shrinkage behaviour through parameters in relation to soil properties. Three plots within the FILTER Project, which were irrigated for summer and winter irrigated cropping with around 1000 m3/ha every 2 weeks with different saline sewage effluent concentrations for >5 years, were sampled from the top horizon to 1.00 m depth. The exchangeable sodium percentage is greatly decreased due to the application of low salt concentration except in the deep horizon. Soil structural properties such as aggregate strength and hydraulic properties are improved, especially in topsoil horizon. The stabilised soil structure reduces the volume change of structural shrinkage. Three parameters of the shrinkage model, defined as α, m, and n, present different physical meanings in relation to soil structure. Parameters α and m have similar functions, both a significantly exponential relationship with aggregate strength and a linear relationship with structural and residual shrinkages, whereas parameter n has a significantly linear relationship with aggregate strength and with the slope of the proportional shrinkage. The relation between parameters of the model and shrinkage behaviour facilitates the prediction of changes in pore water and soil structure and will be a useful tool for modelling water flow in non-rigid soils.
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Gu, Xiang, Shang Ying Xie, and Shao Min Jia. "Analysis of Parameters Influence on Structure of Continuous Curved Bridge." Applied Mechanics and Materials 501-504 (January 2014): 1251–54. http://dx.doi.org/10.4028/www.scientific.net/amm.501-504.1251.
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In the modern urban bridge projects,especially the urban interchange projects and the urban viaduct projects,the long-span curved bridge with the small radius is often inevitably used,considering the transportation under bridges,pipelines and aesthetic factors.This kind of long-span curved bridge with small radius was adopted on the south of Second Ring Road in Chendu of the project of "Two Expressways,Two Extended Roads,Two Ring Roads".The influence,which the change of the parameters on the structure had,was analyzed by using the finite element software of Midas Civil 2010.Then,the parameter which had greatest impact on the inner force of the structure was found.The girder depth is the key parameter in design.
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Li, Jun, and Jian Zhou. "3-D Numerical Simulation for Large-Diameter Cast-In Situ Tubular Pile." Applied Mechanics and Materials 71-78 (July 2011): 4009–13. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.4009.
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Large-diameter cast-in-situ tubular pile (shorted as LTP) is a new, efficiency and energy saving, environmental protection pile and has been widely put into use in the foundation treatment. Using finite element method (FEM) to analyze and study the behavior of LTP is a very effective research method. This paper adopted the finite element computation software ANSYS 11.0 to conduct a 3-D numerical simulation for the LTP of a typical project. In this paper, it introduced how to realize the finite element model, specifically discussed how to select the appropriate key parameters and proposed an effective method and steps base on experience to determine the key parameters. By calculating, compared the calculated Q-S curve with the measured one and then analyzed the settlement behavior and the inner friction distribution of LTP, it is found that the inner friction only emerge at the bottom of the soil core and the upper part nearly does not have friction. The critical point in depth decreased and the maximum inner friction increased with the increasement of the load. Under the ultimate load, the sphere of influence of LTP decreased rapidly and the inner friction increased significantly.