Journal articles: 'Metric thread'

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Andrii, Dovhopolov, Nekrasov Sergiy, Zhyhylii Dmytro, Savchenko Yevheniy, and Stupin Borys. "Modeling of a Stress-Strain State of Detachable Connection in Details of Reinforced Composite Materials with Cea Method." Strojnícky časopis - Journal of Mechanical Engineering 70, no. 1 (April 1, 2020): 17–28. http://dx.doi.org/10.2478/scjme-2020-0002.

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AbstractIn order to study the strength of the proposed rope threaded joint for machine parts made of reinforced composite materials, a modeling of a stress-strain state was conducted using the software of finite-element analysis LS-DYNA. Stress-strain state modeling was conducted for a rope threaded joint, affecting on the main performance parameters considered to be p – thread pitch (p = 4 mm), and t – thread depth (t = 1 mm). The main thread parameters taken for the model were up to the metric thread М6 (ISO 724:1993) parameters.

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Gorynin, V. I., and A. A. Chizhik. "Stress intensity factor for a metric fastening thread." Strength of Materials 21, no. 3 (March 1989): 318–21. http://dx.doi.org/10.1007/bf01529182.

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Katzwinkel, Tim, Esanula Mohammad, Philipp Silberkuhl, and Manuel Löwer. "THREAD ROLLING REPAIR METHOD FOR 3D PRINTED BOLTS." Proceedings of the Design Society 1 (July 27, 2021): 3141–48. http://dx.doi.org/10.1017/pds.2021.575.

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AbstractWithin this paper, a new method for the quality refinement of external metric standard threads on 3Dprinted bolts is presented. The repair method is based on the application of thread rolling technology, which is applied in terms of cold forming after the regular printing has been finished. The explorative study proves, that the investigated technology has a good potential to solve known precision issues in FDM 3D printing regarding the required accuracy for function fulfilling standardized threads. The application of thread rolling can be done manually and with minimal tool effort, which makes the technology particularly attractive for low cost applications.

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Shchurov, I. A., E. V. Nemitova, A. V. Shchurova, and D. V. Ardashev. "Metric Buttress Thread Milling and Turning on CNC Machines." International Journal of Automotive and Mechanical Engineering 15, no. 2 (June 30, 2018): 5146–60. http://dx.doi.org/10.15282/ijame.15.2.2018.1.0398.

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Gorynin, V. I., and S. Yu Kondrat'ev. "Determination of the stress concentration in a metric thread." Strength of Materials 18, no. 9 (September 1986): 1164–68. http://dx.doi.org/10.1007/bf01522797.

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Lehnhoff, Terry F., and Bradley A. Bunyard. "Bolt Thread and Head Fillet Stress Concentration Factors." Journal of Pressure Vessel Technology 122, no. 2 (March 7, 2000): 180–85. http://dx.doi.org/10.1115/1.556168.

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Linear finite element analysis (FEA) was performed to determine stress concentration factors for the threads and the bolt head fillet in a bolted connection. The FEA models consisted of axisymmetric representations of a bolt and two circular steel plates each 20 mm in thickness. The bolts studied were 8, 12, 16, 20, and 24-mm-dia grade 10.9 metric bolts with the standard M thread profile. The threads were modeled at both the minimum and maximum allowable depths. The fillet between the bolt shank and bolt head connection was modeled at its minimum radius. Each bolt was loaded to its proof strength. A comparison is made to stress concentration factors typically used in bolted connection design. Stress concentration factors in the head fillet were 3.18, 3.23, 3.63, 3.58, and 3.90 for the 8, 12, 16, 20, and 24-mm bolts, respectively. Thread stress concentration factors were highest in the first engaged thread and decreased in each successive thread moving toward the end of the bolt. Stress concentration factors for the shallow thread models ranged from 1.17 to 4.33, 0.87 to 4.32, 0.83 to 4.67, 0.87 to 4.77, and 0.82 to 4.82 for the 8, 12, 16, 20, and 24-mm bolts, respectively. Likewise, stress concentration factors for the deep thread models ranged from 1.18 to 4.80, 0.88 to 4.80, 0.78 to 5.12, 0.83 to 5.17, and 0.82 to 5.22 for the 8, 12, 16, 20, and 24-mm bolts, respectively. [S0094-9930(00)01402-5]

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Slătineanu, Laurenţiu, Oana Dodun, Irina Beşliu Băncescu, Ionel Coman, Adrian Ghionea, and Traian Mihordea. "Theoretical considerations concerning the profile error of the thread flank." MATEC Web of Conferences 178 (2018): 01006. http://dx.doi.org/10.1051/matecconf/201817801006.

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In the case of metric thread, a possible source of the flank error could be the position of the cutting tool edge, which could not intersect the circular cylindrical surface axis. An analytical method of approximation was applied to model the way in which the flank error is generated by considering some geometrical conditions. A theoretical simplified model was determined to highlight the influence of the thread external diameter and of the distance between the circular cylindrical surface axis and the thread rectilinear generatrix on the profile error of thread flank.

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Mutambi, Joshua, and Li-jun Yu. "Application of digital image analysis method in metric screw thread metrology." Journal of Shanghai University (English Edition) 8, no. 2 (June 2004): 208–12. http://dx.doi.org/10.1007/s11741-004-0042-2.

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Novoselac, Stipica, Todor Ergić, Dražan Kozak, and Aleksandar Sedmak. "Influence of Semi-Circular Cracks on Threaded Connection Fatigue by Means of Kitagawa-Takahashi Diagram and El Haddad Equation." Key Engineering Materials 665 (September 2015): 133–36. http://dx.doi.org/10.4028/www.scientific.net/kem.665.133.

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Evaluation of semi-circular surface crack influence on threaded connection fatigue behavior, made of 42CrMo4 heat treatable steel, was carried out. Crack diameters were defined as 0.02, 0.05, 0.1, and 0.15 mm. Influence of semi-circular surface cracks was investigated by means of Kitagawa–Takahashi diagram and El Haddad equation. Assessments were done for survival probability of 99% on detailed FE model with normal metric thread profile and preload force at 70% of force at bolt yield point. The most critical location on threaded connections usually are thread roots which contain a very high notch effect. In order to accurately consider multiaxial stress field in thread root, multiaxial fatigue stress criterion based on a critical plane theory for fatigue assessment, was used. Mean stress influence was taken into account by means of Haigh diagram. Variable amplitude loading history of low-high (Lo-Hi) sequence spectrum was analyzed with the numerical algorithm of Rainflow cycle counting in the time domain. Fatigue damage was calculated according to the modified Palmgren-Miner linear damage accumulation hypothesis.

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Liao, Yunn Shiuan, and Chin Nan Chen. "A Study of a Strategy for Threading Titanium Alloy." Advanced Materials Research 753-755 (August 2013): 323–32. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.323.

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The cutting of precision threads is an important manufacturing process. Several passes are needed to complete the cutting of a thread and the choice of appropriate cutting speed and depth of cut for each cutting pass is essential. The cutting efficiency and tool life are significantly affected by these two parameters, especially when cutting threads in difficult-to-cut materials, such as titanium alloy. This paper proposes the concept of an equal undeformed chip area for all cutting passes, in order to determine the depth of cut for each pass. The principal goal is to maintain the same cutting force throughout the cutting process. Using tool geometry, the relationship between the cumulative depth of cut and the undeformed chip area for each cutting pass are derived. The depth of cut of each corresponding cutting pass can be determined, once the dimensions of the thread and the number of cutting passes are specified. Experiments were conducted to cut an ISO metric screw thread, with a pitch of 0.5 mm, on a 40 mm in diameter bar. It was found that, for the same total number of cutting passes, the tool wear was less than that suggested by the tool makers, when a depth of cut for each pass was determined using the proposed method. The thread could be cut using a higher cutting speed, resulting in a much shorter machining time. In addition, the proposed strategy also allowed completion of cutting using less cutting passes. A 25% increase in efficiency was noted for the specific thread used in the experiment.

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Hankin, Robin K. S. "Light Inextensible Strings (Thread) Under Tension in the Schwarzschild Geometry." Physics Educator 03, no. 02 (June 2021): 2150005. http://dx.doi.org/10.1142/s2661339521500050.

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Light inextensible string under tension is a stalwart feature of elementary physics. Here I show how considering such a string in the vicinity of a black hole, with the help of computer algebra systems, can generate insight into the Schwarzschild geometry in the context of an undergraduate homework problem. Light taut strings minimize their proper length, given by integrating the spatial component of the Schwarzschild metric along the string. The path itself is given by straightforward numerical solution to the Euler–Lagrange equations. If the string is entirely outside the event horizon, its closest approach to the singularity is tangential. At this point the string is visibly curved, surely a memorable and informative insight. The geometry of the Schwarzschild metric induces some interesting nonlocal phenomena: if the distance of closest approach is less than about [Formula: see text], the string self-intersects, even though it is everywhere under tension. Light taut strings furnish a third interpretation of the concept “straight line”, the other two being null geodesics and free-fall world lines. All the software used is available under the GPL.1

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Tian, Zhenzhou, Qing Wang, Cong Gao, Lingwei Chen, and Dinghao Wu. "Plagiarism Detection of Multi-threaded Programs Using Frequent Behavioral Pattern Mining." International Journal of Software Engineering and Knowledge Engineering 30, no. 11n12 (November 2020): 1667–88. http://dx.doi.org/10.1142/s0218194020400252.

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Software dynamic birthmark techniques construct birthmarks using the captured execution traces from running the programs, which serve as one of the most promising methods for obfuscation-resilient software plagiarism detection. However, due to the perturbation caused by non-deterministic thread scheduling in multi-threaded programs, such dynamic approaches optimized for sequential programs may suffer from the randomness in multi-threaded program plagiarism detection. In this paper, we propose a new dynamic thread-aware birthmark FPBirth to facilitate multi-threaded program plagiarism detection. We first explore dynamic monitoring to capture multiple execution traces with respect to system calls for each multi-threaded program under a specified input, and then leverage the Apriori algorithm to mine frequent patterns to formulate our dynamic birthmark, which can not only depict the program’s behavioral semantics, but also resist the changes and perturbations over execution traces caused by the thread scheduling in multi-threaded programs. Using FPBirth, we design a multi-threaded program plagiarism detection system. The experimental results based on a public software plagiarism sample set demonstrate that the developed system integrating our proposed birthmark FPBirth copes better with multi-threaded plagiarism detection than alternative approaches. Compared against the dynamic birthmark System Call Short Sequence Birthmark (SCSSB), FPBirth achieves 12.4%, 4.1% and 7.9% performance improvements with respect to union of resilience and credibility (URC), F-Measure and matthews correlation coefficient (MCC) metric, respectively.

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Zawada-Tomkiewicz, Anna, and Izabela Wierucka. "A case study in technological quality assurance of a metric screw thread." Measurement 114 (January 2018): 208–17. http://dx.doi.org/10.1016/j.measurement.2017.09.021.

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Belova, Yu V., I. N. Malyshev, and S. M. Nikulin. "Calibration of vector circuit analyzers in coaxial channels with a metric screw thread." Measurement Techniques 52, no. 11 (November 2009): 1207–10. http://dx.doi.org/10.1007/s11018-010-9421-1.

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Dragoni, E. "Effect of Thread Pitch and Frictional Coefficient on the Stress Concentration in Metric Nut-Bolt Connections." Journal of Offshore Mechanics and Arctic Engineering 116, no. 1 (February 1, 1994): 21–27. http://dx.doi.org/10.1115/1.2920123.

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By means of the finite element method, this paper establishes how much the stress state within standard metric nut-bolt connections is affected by variations of the thread pitch and of the frictional coefficient. Following a validated simplified approach, the actual three-dimensional geometry of each connection is replaced by an axisymmetric model which recreates the outline of the joint on an appropriate meridional section. The numerical data prove that, for prescribed nominal thread diameter and bolt load, the peak stress in the screw monotonically increases as the pitch decreases. Further, as far as complete sticking between nut and bolt is not achieved, the stress level linearly increases with the coefficient of friction, the rate of variations being higher at the lowest pitches.

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Pujono, Pujono, and Istofa Rifqy Widya Fauzi. "RANCANG BANGUN MESIN SENAI UNTUK ULIR M11." Infotekmesin 9, no. 02 (July 22, 2019): 53–60. http://dx.doi.org/10.35970/infotekmesin.v9i02.11.

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Bolting machine is a machine which is designed to conduct the making process of outside thread without rotating the handlebar of workpiece using hand manually, Therefore, the machine can help the processing in some industries which do not have qualified operators. The purpose of the designing and calculating of machine elements on senai machineis to create a design and make it in real product that can create outside thread with the maximum size of M11, to calculate parts of machine elements, i.e. axis diameter and sprocket chain and to create the real machine product. The designing method used follows these steps, i.e. problem identification, initial idea, improvement of the idea, analysis of design, decision making, and implementation. The result of the evaluation on concept design was the cutter holder on the chuck variable and themover shaft handle. The result of machine elements calculation showed that the electric motor power was 40 watt, shaft diameter was 25 mm with inside diameter of 16 mm, the bearing used was 6205 Ball Bearing, and the thread capacity was M11 metric thread.

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Ramanauskaite, Simona, Asta Slotkiene, Kornelija Tunaityte, Ivan Suzdalev, Andrius Stankevicius, and Saulius Valentinavicius. "Reducing WCET Overestimations in Multi-Thread Loops with Critical Section Usage." Energies 14, no. 6 (March 21, 2021): 1747. http://dx.doi.org/10.3390/en14061747.

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Worst-case execution time (WCET) is an important metric in real-time systems that helps in energy usage modeling and predefined execution time requirement evaluation. While basic timing analysis relies on execution path identification and its length evaluation, multi-thread code with critical section usage brings additional complications and requires analysis of resource-waiting time estimation. In this paper, we solve a problem of worst-case execution time overestimation reduction in situations when multiple threads are executing loops with the same critical section usage in each iteration. The experiment showed the worst-case execution time does not take into account the proportion between computational and critical sections; therefore, we proposed a new worst-case execution time calculation model to reduce the overestimation. The proposed model results prove to reduce the overestimation on average by half in comparison to the theoretical model. Therefore, this leads to more accurate execution time and energy consumption estimation.

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Abdul Ghani, Suzaini, and Hugh Gong. "Seam Quality: Experimental and Modelling Works using the Structural Equation Methodology." Scientific Research Journal 7, no. 1 (June 1, 2010): 13. http://dx.doi.org/10.24191/srj.v7i1.9422.

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Seam quality in terms of appearance and strength were investigated for very light weight fabrics (weight less than 80 g m-1;. Seams were constructed with different sewing parameters, which included types of thread, stitch densities and needle size. Before constructing the seam for appearance and strength evaluation the mechanical properties of all fabrics were determined. The mechanical properties of 48 fabrics were determined using the Kawabata Evaluation System (KES-F), the Fabric Assurance Simple Test (FAST) and an lnstron Tensile Tester. Evaluation of seam quality was performed with respect to all the sewing parameters and the seams were ranked accordingly. The same evaluation ranking for seam appearance and strength was used for further analysis using Structural Equation Modelling (SEM) under AMOS. SEM was used to establish the relationship between seam quality with respect to appearance and strength, and fabric mechanical properties. SEM was adopted to perform confirmative analysis to identify the fabrics mechanical properties that influence seam quality. From the experimental work, it was established that seams constructed with I 00 % spun polyester thread with a ticket number of 75 gave the best ranking in terms of seam strength. This thread performed at optimum values when used with 6.5 stitches per centimetre (spcm) with a Metric needle size (Nm) of 90. For seam appearance, I 00 % spun polyester with a ticket number of 120 and Metric needle size of 80 gave the best ranking. SEM established that extensibility and shear were the main fabric mechanical properties that determine seam quality of very light weight fabrics.

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Sun, Yingcheng, Richard Kolacinski, and Kenneth Loparo. "Transitive Topic Modeling with Conversational Structure Context: Discovering Topics that are Most Popular in Online Discussions." International Journal of Semantic Computing 14, no. 02 (June 2020): 273–93. http://dx.doi.org/10.1142/s1793351x20400103.

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With the explosive growth of online discussions published everyday on social media platforms, comprehension and discovery of the most popular topics have become a challenging problem. Conventional topic models have had limited success in online discussions because the corpus is extremely sparse and noisy. To overcome their limitations, we use the discussion thread tree structure and propose a “popularity” metric to quantify the number of replies to a comment to extend the frequency of word occurrences, and the “transitivity” concept to characterize topic dependency among nodes in a nested discussion thread. We build a Conversational Structure Aware Topic Model (CSATM) based on popularity and transitivity to infer topics and their assignments to comments. Experiments on real forum datasets are used to demonstrate improved performance for topic extraction with six different measurements of coherence and impressive accuracy for topic assignments.

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Vasilescu, Mircea Dorin, and Traian Fleser. "Influence of Technological Parametrs on the Dimension of Threaded Parts Generated with PLA Matherial by FDM 3D Printing." Materiale Plastice 55, no. 4 (December 30, 2018): 718–22. http://dx.doi.org/10.37358/mp.18.4.5108.

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In this research are establish the technology of 3D printable parts by the principle of FDM 3D printed for threaded made by PLA, ABS, Nylon or PETG. In the paper are present first the dimensional generation and specific aspects that need to be considered to produce threaded with internal teeth of the metric, round or trapezoidal type. Generating the threaded appeared as a necessity for the reconditioning or made of the components of the processing machines made both in the process of elaboration of the bachelor�s and the laboratory works, with reduced energy resource consumption and low pollution as low as possible. After the construction, it is identify the dimension that have implications for both mechanical and kinematic resistance to make a product with good cinematic and functional characteristics. After that are made an analysis of the layers generated, both from the computer simulation and from the point of view of the analysis of layers physically generated for a threaded with internal teeth. At the end are presented which are necessary for operations to obtain a product with good features starting from two types of thread generated 8x2 and 10x2 moments.

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Grgić, Ivan, Vjekoslav Wertheimer, Mirko Karakašić, and Željko Ivandić. "3D Printed Clamps for In Vitro Tensile Tests of Human Gracilis and the Superficial Third of Quadriceps Tendons." Applied Sciences 11, no. 6 (March 12, 2021): 2563. http://dx.doi.org/10.3390/app11062563.

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Recent soft tissue studies have reported issues that occur during experimentation, such as the tissue slipping and rupturing during tensile loads, the lack of standard testing procedure and equipment, the necessity for existing laboratory equipment adaptation, etc. To overcome such issues and fulfil the need for the determination of the biomechanical properties of the human gracilis and the superficial third of the quadriceps tendons, 3D printed clamps with metric thread profile-based geometry were developed. The clamps’ geometry consists of a truncated pyramid pattern, which prevents the tendons from slipping and rupturing. The use of the thread application in the design of the clamp could be used in standard clamping development procedures, unlike in previously custom-made clamps. Fused deposition modeling (FDM) was used as a 3D printing technique, together with polylactic acid (PLA), which was used as a material for clamp printing. The design was confirmed and the experiments were conducted by using porcine and human tendons. The findings justify the usage of 3D printing technology for parts manufacturing in the case of tissue testing and establish independence from the existing machine clamp system, since it was possible to print clamps for each prepared specimen and thus reduce the time for experiment setup.

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Doshi, M. A., and Bhaskar B. Reddy. "Determination of sex of adult human clavicle by discriminant function analysis in Marathwada region of Maharashtra." International Journal of Research in Medical Sciences 5, no. 9 (August 26, 2017): 3859. http://dx.doi.org/10.18203/2320-6012.ijrms20173701.

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Background: Determination of biological sex is one of the most important determinations to be made from human remains and is an essential first step in the development of the biological profile in forensics, anthropology and bioarchaeology. The aim of this study was to determine whether sexing of unknown adult human clavicles can be done by applying values of morphometric parameters and formulae generated by present study on adult human clavicles of known sex and to find out the best parameters for sex determination.Methods: Various metric measurements were recorded using osteo metric board, measuring tape, non-elastic thread, sliding calipers and vernier calipers on adult human clavicles.Results: Sex was correctly estimated by using stepwise discriminant function analysis, for the clavicle 93.3 % of males and 94.4% of females, with a total accuracy of 93.7 %. Direct discriminant function analysis, correct estimated sex for the clavicle was 93.9 % in males and 93.3% in females with a total accuracy of 93.7 %.Conclusions: Present study exhibited better classification accuracy for multiple variables than those of single variables. In the clavicle, the most discriminating variables in stepwise analysis are the mid clavicular circumference, posterior curved length, medial 2/3 and lateral 1/3 junction circumference and Weight. In direct analysis, the single most useful variable was the mid clavicular circumference.

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Reddy, Bhaskar B., and M. A. Doshi. "Sex determination from adult human humerus by discriminant function analysis." International Journal of Research in Medical Sciences 5, no. 9 (August 26, 2017): 3891. http://dx.doi.org/10.18203/2320-6012.ijrms20173702.

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Background: Sex determination of unidentified skeletal remains from crime scenes or excavation sites is an important component in the development of the biological profile in forensics, anthropology and bioarchaeology. The purpose of this research is to determine whether sexing of unknown adult human humerus bones can be done by applying values of morphometric parameters and formulae generated by present study on adult human humerus bones of known sex and to find out the best parameters for sex determination.Methods: Various metric measurements were recorded using osteo metric board, measuring tape, non-elastic thread, sliding calipers and Vernier calipers on adult human humerus bones.Results: Sex was correctly estimated by using stepwise discriminant function analysis, for the clavicle 100% of males and 95% of females, with a total accuracy of 98.1%. Direct discriminant function analysis, correct estimated sex for the clavicle was 100% in males and 95% in females with a total accuracy of 98.1%.Conclusions: Present study exhibited better classification accuracy for multiple variables than those of single variables, the most discriminating variables in stepwise analysis are the weight, total length, transverse diameter of head, circumference of midshaft, trochlear width, capitulum width. In direct analysis, the single most useful variable was the transverse diameter of head.

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Hunger, Frank, Mislav Stepinac, Vlatka Rajčić, and Jan-Willem G. van de Kuilen. "Pull-compression tests on glued-in metric thread rods parallel to grain in glulam and laminated veneer lumber of different timber species." European Journal of Wood and Wood Products 74, no. 3 (January 12, 2016): 379–91. http://dx.doi.org/10.1007/s00107-015-1001-2.

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Zlobin, A. V., and S. É. Tarasevich. "Hydraulic Resistance of Pipes with Uniform Continuous Roughness in the Form of a Metric Thread of Varying Profile and an Inserted Twisted Tape." Journal of Engineering Physics and Thermophysics 93, no. 5 (September 2020): 1226–32. http://dx.doi.org/10.1007/s10891-020-02225-1.

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Abdul Ghani, Suzaini, and Hugh Gong. "Seam Quality: Experimental and Modelling Works using the Structural Equation Methodology." Scientific Research Journal 7, no. 1 (June 30, 2010): 13. http://dx.doi.org/10.24191/srj.v7i1.5008.

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Seam quality in terms ofappearance and strength were investigatedfor very light weight fabrics (weight less than 80 g m"). Seams were constructed with different sewing parameters, which included types ofthread, stitch densities and needle size. Before constructing the seam for appearance and strength evaluation the mechanical properties of all fabrics were determined. The mechanical properties of 48 fabrics were determined using the Kawabata Evaluation System (KES-F), the Fabric Assurance Simple Test (FAST) and an Instron Tensile Tester. Evaluation ofseam quality was performed with respect to all the sewingparameters and the seams were ranked accordingly. The same evaluation ranking for seam appearance and strength was used for further analysis using Structural Equation Modelling (SEM) under AMOS. SEM was used to establish the relationship between seam quality with respect to appearance andstrength, andfabric mechanical properties. SEM was adopted to perform confirmative analysis to identify the fabrics mechanical properties that influence seam quality. From the experimental work, it was established that seams constructed with 100 % spun polyester thread with a ticket number of75gave the best ranking in terms ofseam strength. This threadperformedat optimum values when used with 6.5 stitches per centimetre (spcm) with a Metric needle size (Nm) of 90. For seam appearance, 100 % spun polyester with a ticket number of120 and Metric needle size of80 gave the best ranking. SEM established that extensibility and shear were the main fabric mechanical properties that determine seam quality ofvery light weight fabrics.

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Maiboroda, Victor, Dmytro Tarhan, Dmytro Dzhulii, and Ivanna Slobodianiuk. "Features of Magneto-Abrasive Machining of Taps." Acta Mechanica et Automatica 14, no. 1 (March 1, 2020): 1–7. http://dx.doi.org/10.2478/ama-2020-0001.

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AbstractThe features of magneto-abrasive machining of taps for metric thread cutting were investigated. The calculation method of integral intensity of the magneto-abrasive machining of the working surfaces of the taps by the quantitative values of normal and tangential components of moving speed of the quasi-stable volumes of the magneto-abrasive tool was developed. Based on the results of calculations, it was possible to predict the probable influence of the taps’ location in the working zone on the quality and efficiency of machining their working surfaces. The calculation method is relevant for taps of all diameters with a profile angle of 60°. The working surfaces of the tool would not be effectively machined if the location angle of taps to the plane of the working zone of the machine equals 20–60°. Depending on the expected major polishing or strengthening effect of magneto-abrasive machining, the taps are required to be located at an angle of 60–90° to the plane of the working zone of the machine.

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Le, Ngoc Thuy, and Doan B. Hoang. "A Threat Computation Model using a Markov Chain and Common Vulnerability Scoring System and its Application to Cloud Security." Journal of Telecommunications and the Digital Economy 7, no. 1 (March 30, 2019): 37–56. http://dx.doi.org/10.18080/jtde.v7n1.181.

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Securing cyber infrastructures has become critical because they are increasingly exposed to attackers while accommodating a huge number of IoT devices and supporting numerous sophisticated emerging applications. Security metrics are essential for assessing the security risks and making effective decisions concerning system security. Many security metrics rely on mathematical models, but are mainly based on empirical data, qualitative methods, or compliance checking, and this renders the outcome far from satisfactory. Computing the probability of an attack, or more precisely a threat that materialises into an attack, forms an essential basis for a quantitative security metric. This paper proposes a novel approach to compute the probability distribution of cloud security threats based on a Markov chain and Common Vulnerability Scoring System. Moreover, the paper introduces the method to estimate the probability of security attacks. The use of the new security threat model and its computation is demonstrated through their application to estimating the probabilities of cloud threats and types of attacks.

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Jażdżewska, Magdalena, and Michał Bartmański. "Nanotubular Oxide Layer Formed on Helix Surfaces of Dental Screw Implants." Coatings 11, no. 2 (January 20, 2021): 115. http://dx.doi.org/10.3390/coatings11020115.

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Surface modification is used to extend the life of implants. To increase the corrosion resistance and improve the biocompatibility of metal implant materials, oxidation of the Ti-13Nb-13Zr titanium alloy was used. The samples used for the research had the shape of a helix with a metric thread, with their geometry imitating a dental implant. The oxide layer was produced by a standard electrochemical method in an environment of 1M H3PO4 + 0.3% HF for 20 min, at a constant voltage of 30 V. The oxidized samples were analyzed with a scanning electron microscope. Nanotubular oxide layers with internal diameters of 30–80 nm were found. An analysis of the surface topography was performed using an optical microscope, and the Sa parameter was determined for the top of the helix and for the bottom, where a significant difference in value was observed. The presence of the modification layer, visible at the bottom of the helix, was confirmed by analyzing the sample cross-sections using computed tomography. Corrosion tests performed in the artificial saliva solution demonstrated higher corrosion current and less noble corrosion potential due to incomplete surface coverage and pitting. Necessary improved oxidation parameters will be applied in future work.

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Malcom, Jacob W., Whitney M. Webber, and Ya-Wei Li. "A simple, sufficient, and consistent method to score the status of threats and demography of imperiled species." PeerJ 4 (July 14, 2016): e2230. http://dx.doi.org/10.7717/peerj.2230.

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Managers of large, complex wildlife conservation programs need information on the conservation status of each of many species to help strategically allocate limited resources. Oversimplifying status data, however, runs the risk of missing information essential to strategic allocation. Conservation status consists of two components, the status of threats a species facesandthe species’ demographic status. Neither component alone is sufficient to characterize conservation status. Here we present a simple key for scoring threat and demographic changes for species using detailed information provided in free-form textual descriptions of conservation status. This key is easy to use (simple), captures the two components of conservation status without the cost of more detailed measures (sufficient), and can be applied by different personnel to any taxon (consistent). To evaluate the key’s utility, we performed two analyses. First, we scored the threat and demographic status of 37 species recently recommended for reclassification under the Endangered Species Act (ESA) and 15 control species, then compared our scores to two metrics used for decision-making and reports to Congress. Second, we scored the threat and demographic status of all non-plant ESA-listed species from Florida (54 spp.), and evaluated scoring repeatability for a subset of those. While the metrics reported by the U.S. Fish and Wildlife Service (FWS) are often consistent with our scores in the first analysis, the results highlight two problems with the oversimplified metrics. First, we show that both metrics can mask underlying demographic declines or threat increases; for example, ∼40% of species not recommended for reclassification had changes in threats or demography. Second, we show that neither metric is consistent with either threats or demography alone, but conflates the two. The second analysis illustrates how the scoring key can be applied to a substantial set of species to understand overall patterns of ESA implementation. The scoring repeatability analysis shows promise, but indicates thorough training will be needed to ensure consistency. We propose that large conservation programs adopt our simple scoring system for threats and demography. By doing so, program administrators will have better information to monitor program effectiveness and guide their decisions.

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Armentia, Mikel, Mikel Abasolo, Ibai Coria, and Abdel-Hakim Bouzid. "On the Use of a Simplified Slip Limit Equation to Predict Screw Self-Loosening of Dental Implants Subjected to External Cycling Loading." Applied Sciences 10, no. 19 (September 26, 2020): 6748. http://dx.doi.org/10.3390/app10196748.

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Self-loosening of the prosthetic screws is a major mechanical problem affecting roughly 10% of dental implants, according to the literature. This phenomenon may lead to micro-movements that produce crestal bone loss, peri-implantitis, or structural failure of the implant assembly. In this paper, a simple and effective tool to predict self-loosening under masticatory loads is presented. The loads acting on the screw are obtained from a simple finite element (FE) model, and introduced in a mathematical formula that calculates the torque needed to loosen the screw; self-loosening will occur when this torque becomes zero. In this sense, all the parameters involved in self-loosening phenomenon can be easily identified, and their effect quantified. For validating purposes, 90 experimental tests were performed in a direct stress test bench. As a result, a powerful tool with a maximum experimental error of 7.6% is presented, allowing dental implant manufacturers to predict eventual occurrence of self-loosening in their developed dental implant products and take corrective actions at preliminary design stage. Furthermore, the following clinical implications can be directly derived from the methodology: a higher screw preload, that is a higher tightening torque, improves self-loosening response of the dental implant and, similarly, for a given preload force, higher friction coefficient and screw metric, as well as lower pitch and thread angle values, are also found to be beneficial.

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van Haastrecht, Max, Bilge Yigit Ozkan, Matthieu Brinkhuis, and Marco Spruit. "Respite for SMEs: A Systematic Review of Socio-Technical Cybersecurity Metrics." Applied Sciences 11, no. 15 (July 27, 2021): 6909. http://dx.doi.org/10.3390/app11156909.

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Cybersecurity threats are on the rise, and small- and medium-sized enterprises (SMEs) struggle to cope with these developments. To combat threats, SMEs must first be willing and able to assess their cybersecurity posture. Cybersecurity risk assessment, generally performed with the help of metrics, provides the basis for an adequate defense. Significant challenges remain, however, especially in the complex socio-technical setting of SMEs. Seemingly basic questions, such as how to aggregate metrics and ensure solution adaptability, are still open to debate. Aggregation and adaptability are vital topics to SMEs, as they require the assimilation of metrics into an actionable advice adapted to their situation and needs. To address these issues, we systematically review socio-technical cybersecurity metric research in this paper. We analyse aggregation and adaptability considerations and investigate how current findings apply to the SME situation. To ensure that we provide valuable insights to researchers and practitioners, we integrate our results in a novel socio-technical cybersecurity framework geared towards the needs of SMEs. Our framework allowed us to determine a glaring need for intuitive, threat-based cybersecurity risk assessment approaches for the least digitally mature SMEs. In the future, we hope our framework will help to offer SMEs some deserved respite by guiding the design of suitable cybersecurity assessment solutions.

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Cheng, Congcong, Guanghan Bai, Yun-An Zhang, and Junyong Tao. "Improved integrated metric for quantitative assessment of resilience." Advances in Mechanical Engineering 12, no. 2 (February 2020): 168781402090606. http://dx.doi.org/10.1177/1687814020906065.

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Resilience provides a new approach that system administrators can use in the design and analysis of engineering systems to enhance the ability of such systems to withstand uncertain threats. In this article, an improved integrated metric is proposed for the quantitative assessment of resilience. The proposed metric is constructed in the form of a summation of two capacities: absorptive and restorative capacities. A weight coefficient is assigned to each capacity to enhance the flexibility according to various system requirements of stakeholders. In addition, based on the absolute time scale, a new time factor is proposed and incorporated into the resilience metric to quantify the effect of time on system performance. To test the performance of the proposed metric, three experimental studies are conducted wherein the proposed metric is compared with two other metrics reported in the literature. The results indicate that the proposed metric extends the flexibility of the previous metrics to systems where the time scale is addressed, and that the numerical values of resilience lie in a proper range and can be compared conveniently across different engineering systems. Furthermore, an example of an information exchange network is adopted to demonstrate the applicability of the proposed metric.

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Zhang, Yue, Guosheng Li, and Tengjiao Guo. "Spatiotemporal Patterns and Evolution of Storm Surge Threats along the Southeastern Coastline of China." Atmosphere 10, no. 2 (February 1, 2019): 61. http://dx.doi.org/10.3390/atmos10020061.

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The variability of storm surge poses a significant threat to coastal areas. A new metric named Accumulated Storm surge Potential Impact (ASPI) is proposed based on a new intensity parameter that removes other components from storm surge-induced water level rise. This new metric quantifies storm surge threat by combining frequency and intensity. The results show that storm surge threat has increased since the late 1990s due to greater general storm surges. The extreme storm surge threat did not follow the increasing trend until the mid-2000s. Different regional distribution patterns are found along this coast. The storm surge threat exhibited a -++ zonal tripole pattern, the negative phase was along the north coastline of Hangzhou Gulf and the positive phase was from the center to southern coast area of Zhejiang province and along the eastern coast area of Leizhou Peninsula. Long-term storm surge threats change spatial distribution pattern in three periods. More precarious threats from the center to southern coast areas of Zhejiang province illustrated a poleward shift of storm surge threats consistent with the trend of long-term tropical cyclone landfall. Meanwhile, the strong threat along the eastern coast line of Leizhou Peninsula was sustained from 1960 to 1995, then became weaker from 1996 to 2015. The evolution pattern of storm surge threat along the southeastern coastline of China could be applied for coastal adaptation research under climate change scenarios.

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Jautzy, Timothée, Pierre-Alexis Herrault, Valentin Chardon, Laurent Schmitt, and Gilles Rixhon. "Measuring river planform changes from remotely sensed data – a Monte Carlo approach to assessing the impact of spatially variable error." Earth Surface Dynamics 8, no. 2 (June 3, 2020): 471–84. http://dx.doi.org/10.5194/esurf-8-471-2020.

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Abstract. Remotely sensed data from fluvial systems are extensively used to document historical planform changes. However, geometric and delineation errors inherently associated with these data can result in poor or even misleading interpretation of measured changes, especially rates of channel lateral migration. It is thus imperative to take into account a spatially variable (SV) error affecting the remotely sensed data. In the wake of recent key studies using this SV error as a level of detection, we introduce a new framework to evaluate the significance of measured channel migration. Going beyond linear metrics (i.e. migration vectors between diachronic river centrelines), we assess significance through a channel polygon method yielding a surficial metric (i.e. quantification of eroded, deposited, or eroded-then-deposited surfaces). Our study area is a mid-sized active wandering river: the lower Bruche, a ∼20 m wide tributary of the Rhine in eastern France. Within our four test sub-reaches, the active channel is digitised using diachronic orthophotos (1950 and 1964), and the SV error affecting the data is interpolated with an inverse-distance weighting (IDW) technique. The novelty of our approach arises from then running Monte Carlo (MC) simulations to randomly translate active channels and propagate geometric and delineation errors according to the SV error. This eventually leads to the computation of percentage of uncertainties associated with each of the measured planform changes, which allows us to evaluate the significance of the planform changes. In the lower Bruche, the uncertainty associated with the documented changes ranges from 15.8 % to 52.9 %. Our results show that (i) orthophotos are affected by a significant SV error; (ii) the latter strongly affects the uncertainty of measured changes; and (iii) the significance of changes is dependent on both the magnitude and the shape of the surficial changes. Taking the SV error into account is strongly recommended even in orthorectified aerial photos, especially in the case of mid-sized rivers (<30 m width) and/or low-amplitude river planform changes (<1 m2m-1yr-1). In addition to allowing detection of low-magnitude planform changes, our approach is also transferable as we use well-established tools (IDW and MC): this opens new perspectives in the fluvial context (e.g. multi-thread river channels) for robustly assessing surficial channel changes.

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McDonald, Kenneth, Marshall Malone, Alex Fumerelle, Madison Oliver, and Mack Ohlinger. "Consequence Management Assessment Method Synthesis for Combatant Commands." Industrial and Systems Engineering Review 3, no. 2 (July 16, 2015): 131–42. http://dx.doi.org/10.37266/iser.2015v3i2.pp131-142.

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One of the most important roles that the US fulfills in the global war on terror and their integration with Partner Nations (PNs) is minimizing the threats and effects of weapons of mass destruction (WMD) as well as Chemical, Biological, Radiological, Nuclear and Explosive (CBRNE) attacks by enemy nations, rogue elements, or terrorist groups around the world. The Defense Threat Reduction Agency (DTRA) currently implements an assessment framework for determining a PN’s state of CBRNE readiness, but it is unable to conceptualize that assessment at a regional or Combatant Command (CCMD) level. This research uses the Systems Decision Process (SDP) to create an assessment metric that is capable of synchronizing PN CBRNE readiness across a CCMD into a single assessment. This research is focused on developing an effective and flexible Microsoft Access database, which evaluates all global PNs across a wide array of metrics and then synthesizes them through multi-purpose objectives in order to develop an encompassing assessment framework at the CCMD level.

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Khan, Abdul Malik, Naveed Iqbal, Adnan Ahmed Khan, Muhammad Faisal Khan, and Attiq Ahmad. "Detection of Intermediate Spoofing Attack on Global Navigation Satellite System Receiver Through Slope Based Metrics." Journal of Navigation 73, no. 5 (April 3, 2020): 1052–68. http://dx.doi.org/10.1017/s0373463320000168.

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A spoofing attack on a global navigation satellite system (GNSS) receiver is a threat to a significant community of GNSS users due to the high stakes involved. This paper investigates the use of slope based metrics for the detection of spoofing. The formulation of slope based metrics involves monitoring correlators along with tracking correlators in the receiver's channel, which are slaved to the prompt tracking correlator. In this study, using some candidate metrics, detectors have been formed through the analysis of simulated spoofing attacks. A theoretical variance of each metric has also been calculated as a reference for the threshold. A threshold is estimated using the measured variance from the clean signals, for specific false alarm rate. By using the measured threshold, detectors are formed based on slope metrics. These detectors have been tested using TEXBAT data. The results show that the differential slope metrics have good performance. The results have also been compared with some other techniques of spoofing detection.

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Ashtekar, Abhay, Carlo Rovelli, and Lee Smolin. "Weaving a classical metric with quantum threads." Physical Review Letters 69, no. 2 (July 13, 1992): 237–40. http://dx.doi.org/10.1103/physrevlett.69.237.

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Fedosov, L. I. "Improved method of producing accurate metric threads." Chemical and Petroleum Engineering 24, no. 1 (January 1988): 51–52. http://dx.doi.org/10.1007/bf01150559.

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Midega, Janet. "Estimating the global burden of antimicrobial resistance: Reflections on current methods and data needs." Wellcome Open Research 5 (March 18, 2020): 48. http://dx.doi.org/10.12688/wellcomeopenres.15680.1.

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The prioritisation of policy action, research and the evaluation of progress towards curbing the threat of Antimicrobial Resistance (AMR) is dependent on our knowledge of its burden. The burden of AMR, like that of other causes of death and morbidity, is an important metric that not only provides the opportunity for generating and using data on periodic measures for timely and reliable updates on the prevailing disease situation and its potential to get better or worse, but also guides the development and positioning of interventions, including estimating the costs and benefits of interventions. The urgency with which AMR must be combatted as a global public health threat requires the need to determine and apply the most suitable methods, models and metrics for estimating the global burden of AMR to better inform decisions on how to best manage AMR.

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Harmon, Thomas C., Robyn L. Smyth, Sudeep Chandra, Daniel Conde, Ramesh Dhungel, Jaime Escobar, Natalia Hoyos, et al. "Socioeconomic and Environmental Proxies for Comparing Freshwater Ecosystem Service Threats across International Sites: A Diagnostic Approach." Water 10, no. 11 (November 4, 2018): 1578. http://dx.doi.org/10.3390/w10111578.

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In this work, we develop and test proxy-based diagnostic tools for comparing freshwater ecosystem services (FWES) risks across an international array of freshwater ecosystems. FWES threats are increasing rapidly under pressure from population, climate change, pollution, land use change, and other factors. We identified spatially explicit FWES threats estimates (referred to as threat benchmarks) and extracted watershed-specific values for an array of aquatic ecosystems in the Western Hemisphere (Ramsar sites). We compared these benchmark values to values extracted for sites associated with an international FWES threat investigation. The resulting benchmark threats appeared to provide a meaningful context for the diagnostic assessment of study site selection by revealing gaps in coverage of the underlying socio-environmental problem. In an effort to simplify the method, we tested regularly updated environmental and socioeconomic metrics as potential proxies for the benchmark threats using regression analysis. Three category proxies, aggregated from (i) external (global to regional, climate-related), (ii) internal (watershed management-related), and (iii) socioeconomic and governance related proxies produced strong relationships with water supply threat benchmarks, but only weak relationships with biodiversity-related and nutrient regulation benchmark threats. Our results demonstrate the utility of advancing global FWES status and threat benchmarks for organizing coordinated research efforts and prioritizing decisions with regard to international socio-environmental problems.

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Yun, Youngsun, Changdon Kee, Jason Rife, Ming Luo, Sam Pullen, and Per Enge. "Detecting RFI Through Integrity Monitoring at a DGPS Reference Station." Journal of Navigation 59, no. 3 (August 23, 2006): 403–22. http://dx.doi.org/10.1017/s0373463306003882.

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Because GPS is a radio navigation system which has a very low power level, it is vulnerable to RFI. Excessive RFI could cause receiver performance degradation, such as degradation of position accuracy, loss of lock and increased acquisition time. After GPS modernization plans introduce dual-frequency civil signals to mitigate ionospheric errors, RFI will remain as one of the dominant threats for differential GPS navigation systems. Examples of safety-critical civil aviation and military missions threatened by RFI include the Local Area Augmentation System (LAAS) and the Joint Precision Approach and Landing System (JPALS). This paper focuses on RFI mitigation through integrity monitoring for a DGPS system like LAAS or JPALS. The mitigation strategy consists of two parts. First, the paper develops a new RFI detection method, using a raw divergence statistic. Second, the paper investigates strategies for maintaining integrity in the case that RFI is detected.To validate the utility of the divergence-based RFI monitor, this paper takes an experimental approach. The experiments assess the performance of the divergence metric and compare it to existing alternatives for RFI detection, such as metrics for Automatic Gain Control (AGC) and carrier-to-noise ratio (C/N0). Generating a monitoring threshold for these statistics proves challenging, because the threshold depends both on the type of RFI threat (e.g. continuous wave, narrow band, wideband, pulsed) and on environmental conditions, such as temperature. As experiments illustrate, the divergence statistic resolves these limitations, as divergence directly estimates ranging source error, independent of the type of RFI threat or the environmental conditions.

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Westphal, Knut. "An optimized coating system for fasteners with metric threads." ATZ worldwide 107, no. 5 (May 2005): 8–10. http://dx.doi.org/10.1007/bf03224737.

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Monsees, Elizabeth, Elizabeth Monsees, Ann Wirtz, Angela Myers, Angela Myers, Alaina Burns, Chris Day, et al. "1052. Antimicrobial Stewardship: On Board with Lean Daily Management System." Open Forum Infectious Diseases 6, Supplement_2 (October 2019): S371. http://dx.doi.org/10.1093/ofid/ofz360.916.

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Abstract Background Limited guidance exists on how to design and measure the efficiency and effectiveness of an antimicrobial stewardship program (ASP). Our established ASP sought to broaden interprofessional accountability and enhance our programmatic efficiency by employing Lean Daily Management System (DMS) procedures. Methods To improve ASP communication, a visual and systematic approach to identify, address, and resolve ASP projects while quantifying nontraditional metrics measuring the efficiency and effectiveness was developed. Through shared discussions, an interdisciplinary group of stakeholders produced the following deliverables: (a) established shared programming goals/metrics; (b) improved prioritization methods and project tracking through completion; (c) developed readiness and metric boards to display achievements, current activity, and metrics; (d) identified programming threats and strategies to strengthen our provided services. Results At 6 months following DMS adoption, our ASP has disbanded monthly meetings in lieu of weekly, 15 minute huddles utilizing the readiness and metric boards. We achieved consistent and interprofessional representation where each member is accountable for leading huddles, providing reports, and owning projects. Using a stoplight color system to indicate status, potential ASP influencers are tracked and reported: clinical workload/demands, organizational awareness, equipment/supplies, staffing, project updates, and announcements. The visual identification allows the team to address “quick hits” or escalate resource allocation to solve “big issues” (figure). Program metrics are codified under the domains of delivery, people, quality, safety, and financial stewardship. Administrative leadership has attended huddles and provided positive and constructive feedback to foster a process of continuous improvement. Conclusion Integration of Lean DMS huddles provides a collaborative, interactive and interdisciplinary approach to enhance shared awareness and to broaden the reach and efficiency of our ASP. With project tracking mechanisms in place, our team is refining our problem-solving abilities to ensure a congruent plan between issues raised and established program metrics. Disclosures All authors: No reported disclosures.

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Al-Mhiqani, Mohammed Nasser, Rabiah Ahmad, Z. Zainal Abidin, Warusia Yassin, Aslinda Hassan, Karrar Hameed Abdulkareem, Nabeel Salih Ali, and Zahri Yunos. "A Review of Insider Threat Detection: Classification, Machine Learning Techniques, Datasets, Open Challenges, and Recommendations." Applied Sciences 10, no. 15 (July 28, 2020): 5208. http://dx.doi.org/10.3390/app10155208.

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Insider threat has become a widely accepted issue and one of the major challenges in cybersecurity. This phenomenon indicates that threats require special detection systems, methods, and tools, which entail the ability to facilitate accurate and fast detection of a malicious insider. Several studies on insider threat detection and related areas in dealing with this issue have been proposed. Various studies aimed to deepen the conceptual understanding of insider threats. However, there are many limitations, such as a lack of real cases, biases in making conclusions, which are a major concern and remain unclear, and the lack of a study that surveys insider threats from many different perspectives and focuses on the theoretical, technical, and statistical aspects of insider threats. The survey aims to present a taxonomy of contemporary insider types, access, level, motivation, insider profiling, effect security property, and methods used by attackers to conduct attacks and a review of notable recent works on insider threat detection, which covers the analyzed behaviors, machine-learning techniques, dataset, detection methodology, and evaluation metrics. Several real cases of insider threats have been analyzed to provide statistical information about insiders. In addition, this survey highlights the challenges faced by other researchers and provides recommendations to minimize obstacles.

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Narahari, Adishesh Kalya, Eric J. Charles, J. Hunter Mehaffey, Robert B. Hawkins, Ashish K. Sharma, Victor E. Laubach, Curtis G. Tribble, and Irving L. Kron. "Can Lung Transplant Surgeons Still Be Scientists? High Productivity Despite Competitive Funding." Heart Surgery Forum 22, no. 1 (January 8, 2019): E001—E007. http://dx.doi.org/10.1532/hsf.2024.

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Background: Today’s declining federal budget for scientific research is making it consistently more difficult to become federally funded. We hypothesized that even in this difficult era, surgeon-scientists have remained among the most productive and impactful researchers in lung transplantation. Methods: Grants awarded by the NIH for the study of lung transplantation between 1985 and 2015 were identified by searching NIH RePORTER for 5 lung transplantation research areas. A grant impact metric was calculated for each grant by dividing the sum of impact factors for all associated manuscripts by the total funding for that grant. We used nonparametric univariate analysis to compare grant impact metrics by department. Results: We identified 109 lung transplantation grants, totaling approximately $300 million, resulting in 2304 papers published in 421 different journals. Surgery has the third highest median grant impact metric (4.2 per $100,000). The department of surgery had a higher median grant impact metric compared to private companies (P <.0001). There was no statistical difference in the grant impact metric compared to all other medical specialties, individual departments with multiple grants, or all basic science departments (all P >.05). Conclusions: Surgeon-scientists in the field of lung transplantation have received fewer grants and less total funding compared to other researchers but have maintained an equally high level of productivity and impact. The dual-threat academic surgeon-scientist is an important asset to the research community and should continue to be supported by the NIH.

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Jouini, Mouna, and Latifa Ben Arfa Rabai. "A Security Risk Management Metric for Cloud Computing Systems." International Journal of Organizational and Collective Intelligence 4, no. 3 (July 2014): 1–21. http://dx.doi.org/10.4018/ijoci.2014070101.

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Cloud computing is a growing technology used by several organizations because it presents a cost effective policy to manage and control Information Technology (IT). It delivers computing services as a public utility rather than a personal one. However, despite these benefits, it presents many challenges including access control and security problems. In order to assess security risks, the paper gives an overview of security risk management metrics. Then, it illustrates the use of a cyber security measure to describe an economic security model for cloud computing system. Moreover, it proposes a cloud provider business model for security issues. Finally, the paper shows a solution related to the vulnerabilities in cloud systems using a new quantitative metric to reduce the probability that an architectural components fails. The main aim of this article is to quantify security threats in cloud computing environments due to security breaches using a new security metric.

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Blicharska, Malgorzata, and Grzegorz Mikusinski. "Metrics: a long-term threat to society." Nature 490, no. 7420 (October 2012): 343. http://dx.doi.org/10.1038/490343a.

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Schwartz, Craig S. "A Comparison of Methods Used to Populate Neighborhood-Based Contingency Tables for High-Resolution Forecast Verification." Weather and Forecasting 32, no. 2 (April 1, 2017): 733–41. http://dx.doi.org/10.1175/waf-d-16-0187.1.

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Abstract As high-resolution numerical weather prediction models are now commonplace, “neighborhood” verification metrics are regularly employed to evaluate forecast quality. These neighborhood approaches relax the requirement that perfect forecasts must match observations at the grid scale, contrasting traditional point-by-point verification methods. One recently proposed metric, the neighborhood equitable threat score, is calculated from 2 × 2 contingency tables that are populated within a neighborhood framework. However, the literature suggests three subtly different methods of populating neighborhood-based contingency tables. Thus, this work compares and contrasts these three variants and shows they yield statistically significantly different conclusions regarding forecast performance, illustrating that neighborhood-based contingency tables should be constructed carefully and transparently. Furthermore, this paper shows how two of the methods use inconsistent event definitions and suggests a “neighborhood maximum” approach be used to fill neighborhood-based contingency tables.

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Ehret, U., and E. Zehe. "Series distance – an intuitive metric to quantify hydrograph similarity in terms of occurrence, amplitude and timing of hydrological events." Hydrology and Earth System Sciences 15, no. 3 (March 11, 2011): 877–96. http://dx.doi.org/10.5194/hess-15-877-2011.

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Abstract. Applying metrics to quantify the similarity or dissimilarity of hydrographs is a central task in hydrological modelling, used both in model calibration and the evaluation of simulations or forecasts. Motivated by the shortcomings of standard objective metrics such as the Root Mean Square Error (RMSE) or the Mean Absolute Peak Time Error (MAPTE) and the advantages of visual inspection as a powerful tool for simultaneous, case-specific and multi-criteria (yet subjective) evaluation, we propose a new objective metric termed Series Distance, which is in close accordance with visual evaluation. The Series Distance quantifies the similarity of two hydrographs neither in a time-aggregated nor in a point-by-point manner, but on the scale of hydrological events. It consists of three parts, namely a Threat Score which evaluates overall agreement of event occurrence, and the overall distance of matching observed and simulated events with respect to amplitude and timing. The novelty of the latter two is the way in which matching point pairs on the observed and simulated hydrographs are identified: not by equality in time (as is the case with the RMSE), but by the same relative position in matching segments (rise or recession) of the event, indicating the same underlying hydrological process. Thus, amplitude and timing errors are calculated simultaneously but separately, from point pairs that also match visually, considering complete events rather than only individual points (as is the case with MAPTE). Relative weights can freely be assigned to each component of the Series Distance, which allows (subjective) customization of the metric to various fields of application, but in a traceable way. Each of the three components of the Series Distance can be used in an aggregated or non-aggregated way, which makes the Series Distance a suitable tool for differentiated, process-based model diagnostics. After discussing the applicability of established time series metrics for hydrographs, we present the Series Distance theory, discuss its properties and compare it to those of standard metrics used in Hydrology, both at the example of simple, artificial hydrographs and an ensemble of realistic forecasts. The results suggest that the Series Distance quantifies the degree of similarity of two hydrographs in a way comparable to visual inspection, but in an objective, reproducible way.

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Journal articles on the topic 'Metric thread'

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