Добірка наукової літератури з теми "4011 Environmental engineering"

Abstract. Free Ocean CO2 Enrichment (FOCE) systems are designed to assess the impact of ocean acidification on biological communities in situ for extended periods of time (weeks to months). They overcome some of the drawbacks of laboratory experiments and of field observations by enabling (1) precise control of CO2 enrichment by monitoring pH as an offset of ambient pH, (2) consideration of indirect effects such as those mediated through inter-specific relationships and food-webs, and (3) relatively long experiments with intact communities. Bringing perturbation experiments from the laboratory to the field is however extremely challenging. The goal of this paper is to provide guidelines on the general design, engineering, and sensors required to conduct FOCE experiments. Present and existing FOCE systems are briefly described and examples of data collected presented. Future developments are also addressed as it is anticipated that the next generation of FOCE systems will include, in addition to pH, options for oxygen and/or temperature control. FOCE systems should become an important experimental approach for projecting the future response of marine ecosystems to environmental change.

A numerical heat and mass transfer model with thermophysical properties dependent on the temperature, humidity ratio and atmospheric pressure was developed. The numerical model was verified and validated against literature, and it showed good agreements. The pseudo-transient model provides a low-cost computational tool to evaluate the potential and performance of a dew point evaporative cooling system for a wide range of extreme climate conditions (BWh, BSh, Cw and Aw from Köppen classification). A parametric analysis of different operational and design conditions in the evaporative cooler was conducted. Results show that there is an optimal channel length for given climatic conditions. The Dew-point evaporative cooling (DPEC) system showed that the best thermal performance corresponds to the climate very arid (Hermosillo – BWh) with 4018 comfort hours (83.1%) followed by the climate arid (Monterrey – BSh) with 3470 comfort hours (90.9%), the mild climate (Puebla – Cw) with 295 comfort hours (100%) and the warm climate (Cancun – Aw) with 3452 comfort hours (62.3%). Finally, an engineering correlation for constant atmospheric pressure and channel length was obtained ([Formula: see text] of 93%).

Solar cooking finds a major application in rural areas of Uttarakhand, India, yet its utilization is still limited due to certain limitation such as intermittent nature of solar radiations. This drawback limits solar cooker in becoming a viable alternate solution of LPG and other pollution causing resources such as wood. In order to cater this problem a numerical analysis of box type solar cooker with storage is carried out. The energy stored in the storage material will keep the cooker warm up to the time when food is consumed. Charging and discharging time analysis is performed in with an aim to understand the effect of storage on solar cooker. Heating and cooling characteristic time are being evaluated and analysed with storage. Thermal performance of box type solar cooker is measured in terms of figures of merit according to BIS standards. The effect of storage has also been analysed in terms of charging and discharging time and first figure of merit of box type solar cooker.it has been observed that during discharging the heat is stored for more duration as compared to the charging time as discharge time is approx. 4-5 hours while charging time for the same amount of insolation is around 3-4 hours.

In this study, the permeable-reactive-barrier (PRB) assisted electrokinetic (EK) was used to remediate As/Cr Co-contaminated soil, aiming to explore the optimal remediation conditions and the migration of As/Cr. The effects of PRB active substance, PRB location, voltage gradient and running time on the migration and transformation of Cr and As in simulated As/Cr contaminated kaolin were studied. The optimal parameters were as follows: PRB position was located near the anode (PRB A, the medium of PRB was hydrocalumite (CaAl-LDH)), initial voltage gradient was 1 V/cm, running time was 96 h. Under the optimal conditions, the removal efficiency of total arsenic (TAs) and total chromium (TCr) were 40.1% and 81.0%, respectively. This indicated that EK can effectively migrate As and Cr, and PRB can effectively adsorb As and Cr. The migration of As tends to both anode and cathode, while Cr tends to migrate towards the anode. The XRD patterns and FTIR spectra confirmed that the As immobilized by CaAl-LDH was mainly adsorbed on the surface, while Cr existed in CaAl-LDH by surface adsorption and intercalation.

This study quantitively estimates the energy and environmental impacts of China’s promotion of battery electric vehicles (BEVs) in the context of banning the sale of gasoline vehicles (GVs). Combining the population ecological growth model and the life cycle assessment method, the potential of BEVs promotion in reducing fossil energy (FE) consumption and greenhouse gas (GHG) emissions under different timings of banning GV sales was dynamically simulated and analyzed. The results show that the current life cycle FE consumption and GHG emissions of BEVs are approximately 40.1% and 26.6% lower than those of GVs, respectively. Based on the development of automobile technology and the national energy plan, replacing GVs with BEVs can reduce GHG emissions and FE consumption by up to 43.61–55.81% and 46.33–55.45%, respectively. Compared with the scenario without BEV promotion, if sales of GVs in China are banned between 2040 and 2060, the point at which the carbon peak of the automobile market will be reached will be advanced by approximately two years, and the corresponding carbon peak value will be reduced by approximately 13.58–28.79 million tons of CO2-eq (MtCO2e). In addition, the annual FE savings and GHG emission reductions will reach approximately 2.99–6.35 million TJ and 276.54–488.77 MtCO2e by 2050. This research work will not only help authorities, managers, and the public to better understand the environmental and energy impacts of promoting new energy vehicles, but also provide a forward-looking reference for formulating comprehensive, systematic, and reasonable industrial planning to better promote a green and sustainable transformation of the automotive sector and solve the relevant energy and environmental problems.

The spread of invasive alien plant species (IAPS) is a leading reason for worldwide environmental change due to their effects on biodiversity and humans. Some valued goods from IAPS have been produced, e.g. paper that consists of cellulose fibres from Japanese knotweed. Therefore, the aim of this study was to establish the usability of this paper grade as a printing substrate, since it does not have ideal optical properties as it is expected from commercial office paper. Because it is widely used, inkjet printing technology was employed. Print permanence is essential, especially when printing documents. However, typographic characteristics must be considered to make a text more legible. Two widely used typefaces (Arial and Times) were tested in three commonly used type sizes (8 pt, 10 pt, and 12 pt). The results showed that the paper made from Japanese knotweed could have valuable properties and suitable legibility, especially when using typefaces with a moderate counter size, high x-height, and minimal differences in the letter stroke width to obtain an appropriate typographic tonal density with an adequate type size. Even after exposure to light, the texts printed in a proper type size and stroke width remained visible.

A total of 262 water-related samples were analysed for the presence of Cryptosporidium spp. oocysts, of which 39.3% were positive, over a twelve month period. Similar data were obtained for their occurrence in samples of both raw and treated water from Scotland, with 40.5% of raw water and 40.1% of treated water being positive. Fewer oocysts were detected in the summer than in the autumn, winter or spring. In a 12 month survey of water used for abstraction, oocysts were detected at various times throughout the year in both raw and treated water. A series of conventional and fluorogenic dyes was used, in conjunction with a fluorescent labelled monoclonal antibody, in an attempt to assess their potential fox imprpving the identification of oocysts in water-related samples. In addition, preliminary data regarding the possible use of fluorogenic vital dyes as indicators of in vitro excystation and viability are presented.

Perawat harus memahami dan menentukan spiritualitas mereka sendiri sebelumnya, agar dapat memberikan perawatan yang tepat. Belum ada penelitian terkait kondisi spiritual perawat di salah satu rumah sakit X di Kota Pontianak. Penelitian ini bertujuan untuk mendeskripsikan spiritual well-being perawat rawat inap di rumah sakit X di Kota Pontianak. Penelitian ini menggunakan desain deskriptif survei dengan pendekatan potong lintang (cross-sectional). Perawat pelaksana di ruang rawat inap sebesar 167 responden dipilih dengan teknik proportional random sampling. Instrumen yang digunakan berupa data demografi atau karakteristik responden dan 20 pertanyaan instrumen Spiritual Health and Life-Orientation Measure (SHALOM) versi Indonesia dari Fisher. Hasil analisis dari skoring penjumlahan didapatkan nilai spiritual well-being tinggi pada 40,1% responden. Spiritual well-being berdasarkan domain menunjukkan responden yang memiliki tingkat personal swb tinggi sebanyak 33,5%, tingkat communal swb tinggi sebanyak 36,5%, tingkat transcendental swb tinggi sebanyak 38,3%, dan tingkat environmental swb tinggi sebanyak 34,7%. Item dengan mean tertinggi berdasarkan kelasnya ditemukan ‘mendekatkan diri kepada Tuhan’ (Mean=4,73, SD=0,596) pada kelas ideal, ‘beribadah kepada Sang Pencipta’ (Mean=4,34, SD=0,683) pada kelas kenyataan, dan ‘beribadah kepada Sang Pencipta’ (Mean=4,01, SD=0,905) pada kelas bantuan untuk pasien. Kesimpulan: tingkat Spiritual Well-Being perawat di ruang rawat inap secara umum maupun per domain masih lebih banyak termasuk kategori rendah. Dengan kondisi tersebut rumah sakit dapat memfasilitasi perawat mendapatkan modul/pelatihan spiritual serta memfasilitasi perawat dengan sarana dan prasarana ibadah.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1996.
Includes bibliographical references (leaves 62-67).
by Crist Simon Khachikian.
M.Eng.

Future energy supply infrastructure schemes for the built environment are set to consist of a diverse mix of distributed generation technologies, increasingly stringent local emissions reduction targets, and potentially complex ownership structures. This thesis presents a new modelling method that integrates technical design, green house gas emissions analysis and financial analysis models for new build multi energy vector systems. The model was used to compare and characterise several alternative heating technology options for the carbon constrained design of a generic UK market town residential development. Of the options examined, natural gas combined heat and power based district heating was shown to provide the least cost solution for projects built before 2020. Beyond 2025, electric heat pumps provided the cheapest option in response to the decarbonisation of the grid supplied electricity. The integrated model was used as the basis of an optimised infrastructure design tool. This was applied to determine the least cost energy supply technology mix for a new build community redevelopment scheme at Ebbw Vale, South Wales. It was shown that both the optimal design and corresponding optimal cost is dependent upon the year of build completion for the project and the

Light-weight aggregate has been used successfully for structural and non-structural applications, and its most common use has been in light-weight concrete. Limited research has been done on light-weight grout though and there are no standards in place. The research performed in this study is intended to increase the knowledge of light-weight grout specifically made with expanded shale aggregate. The research presented herein is a pilot study and consists of preliminary aggregate and grout testing that resulted in the mix design of six grout types: three fine grout designs and three coarse grout designs. Conventional normal-weight aggregate was employed in the first grout mix. A light-weight aggregate batch was made with the same material proportions, as well as the same target water-cement (w/c) ratio and cement content. The weight of the cement was increased by 30 percent in the third grout type of each set to determine the effect on strength. The slump, component temperature, unit weight, air content, segregation, cement content, w/c ratio, and compressive strength for each grout type was gathered throughout testing. Correlations between grout testing results are examined and discussed. In addition, the effectiveness of expanded shale grout, other light-weight grouts, and normal-weight grout with respect to compressive strength to cement content ratio are determined. Results of the testing show that all six grout types studied in this research reached the minimum 28-day strength of 13.8 MPa (2000 psi) ASTM standard. In addition, the results indicate that the cement content in expanded shale light-weight grout would need to be increased to reach comparable compressive strengths to that of the normal-weight grout. The comparison between the compressive strength to cement content ratio of the different grouts indicate that normal-weight grout is more efficient. In addition, light-weight grout made with blast furnace slag grout is slightly more efficient than that made with expanded shale; however, this observation was only possible after several crucial assumptions were made about an existing blast furnace slag study. These strength-cement ratios do not account, however, for the benefits of reduced dead loads, improved thermal insulation, and improved sound insulation that could potentially influence the choice of the material used in and the life-cycle cost of the construction. Additional research should be done to verify the results of the ratios and the assumptions made herein. Furthermore, a life-cycle analysis needs to be conducted before a definite conclusion is made about which type grout is more efficient.

The objectives of this research were to 1) measure the extent to which water vapor movement results in water accumulation in freezing base materials; 2) evaluate the effect of soil stabilization on water vapor movement in freezing base materials; 3) determine if the corresponding changes in water content are sufficient to cause frost heave during winter; 4) determine if the corresponding changes in water content are sufficient to cause reductions in stiffness during spring; 5) evaluate relationships between selected material properties, freezing conditions, and the occurrence and impact of water vapor movement; and 6) numerically simulate heat and water movement in selected pavement design scenarios. The research involved extensive laboratory and field testing, statistical analyses, and numerical modeling. The results of the laboratory testing, which included gradations, Atterberg limits, soil classifications, specific gravity and absorption values, electrical conductivity values, moisture-density relationships, soil-water characteristic curves, moisture-stiffness curves, hydraulic conductivity values, and frost susceptibility assessments, were used to characterize each material and enable subsequent statistical analyses. Testing of both treated and untreated materials enabled investigation of a wide variety of material properties. The results of the field testing, which included temperature, moisture content, water potential, elevation, and stiffness data over time, provided the basis for comparing pavement sections with and without capillary barriers and established the framework for numerical modeling. In a pavement section with a capillary barrier underlying the base layer, water vapor movement from the subgrade through the capillary barrier may be expected to increase the water content of the base layer by 1 to 3 percent during a typical winter season in northern Utah for base materials similar to those studied in this research. During winter, cold temperatures create an ideal environment for water vapor to travel upward from the warm subgrade soil below the frost line, through the capillary barrier, and into the base material. Soil stabilization can lead to increased or decreased amounts of water vapor movement in freezing base materials depending on the properties of the stabilized soil, which may be affected by gradation, mineralogy, and stabilizer type and concentration. Accumulation of water from long-term water vapor movement into frost-susceptible base materials underlain by a capillary barrier can lead to frost heave of the base layer as it approaches saturation, as water available in the layer can be redistributed upwards to create ice lenses upon freezing. However, the incremental increase in total water content that may occur exclusively from water vapor movement during a single winter season in northern Utah would not be expected to cause measurable increases in thaw weakening of the base layer during spring. Because water in a base layer overlying a capillary barrier cannot drain until nearly reaching positive pore pressures, the base layer will remain indefinitely saturated or nearly saturated as demonstrated in this research. For materials similar to those studied in this research, potentially important material properties related to the occurrence of water vapor movement during freezing include dry density, percent of material finer than the No. 200 sieve, percent of material finer than 0.02 mm, apparent specific gravity, absorption, initial water content, porosity, degree of saturation, hydraulic conductivity, and electrical conductivity. The rate at which water vapor movement occurs is also dependent on the thermal gradient within the given material, where higher thermal gradients are associated with higher amounts of water vapor movement. The numerical modeling supported the field observations that the capillary barrier effectively trapped moisture in the overlying base material, causing it to remain saturated or nearly saturated throughout the monitoring period. Only non-frost-susceptible aggregate base materials should be specified for use in cold climates in conjunction with capillary barriers, and the base material in this case should be assumed to remain in a saturated or nearly saturated condition during the entire service life of the pavement. Further study is recommended on water vapor movement in freezing aggregate base materials.

In Turkey with increasing energy demand by industrialization and urbanization, hydropower seemed to be the most environmental friendly and sustainable solution for the problem. However, hydropower has also environmental effects especially when hydropower projects are numerous on a single river, and they use almost entire water in the river. Environmental flow as a new term became popular in media with increased density of small hydropower projects in Turkey. It is the required flow in the part of diversion for Run-off River type of hydropower plant in order to protect health of the river
in other words, to balance components of the river, including physico-chemical quality standards, surface and groundwater, geomorphological dynamics, social, economic, cultural and landscape values. In this study, an analysis utilizing hydrological (desktop) environmental flow assessment methods is prepared for Turkey, focusing on the Pazarsuyu Basin as a case study, and the results are compared with the applications done by the Governmental Institutions. Moreover, insufficient applications with regard to environmental flow assessment are given and reasons for public concerns are pointed out due to small hydropower development in Turkey.

In this thesis the impact of the Atatü
rk Dam on social and environmental aspects of the Southeastern Anatolia Project has been discussed in terms of planning and policy making, institutional arrangements, infrastuctural development and human resources development. In order to analyse the impacts of Atatü
rk Dam data related to several components are collected. These components can be listed as resettlement, land acquisition and land consolidation, education, health, gender issues. The results show that the Atatü
rk Resettlement has been done involuntarily. The people mostly have their compensation. However the management abilities of the resettlers for the compensations were poor. Generally the Southeastern Anatolia Project as a large scale multi sectoral projects have positive impacts on the literacy ratio and health standards. Actually the social and environmental aspects of this kind of large scale projects are difficult to predict and measure. Therefore reasonable studies on prediciting the problems related to the environemental and social issues and producing sufficient solutions become more and more important day by day. The Southeastern Anatolia Project becomes an important example for similar projects by considering its both positive and negative impacts

Microalgae can be used to polish secondary treated wastewater by removing nutrients and carbon without the addition of oxygen making it a reduced energy treatment compared to traditional extended aeration systems. The recovered microalgae in turn can be used for biofuels applications such as biogas production via anaerobic digestion and biodiesel production via lipid transesterification. Anaerobic digestion is a more feasible option due to its low energy requirement and on-site power generation ability for water utilities. Nevertheless, anaerobic digestion of microalgae has several challenges with the most difficult being the recalcitrant nature of the cell wall of most microalgae resisting microbial attack during digestion. This has resulted in low methane yields after long retention times during anaerobic digestion. Also, the rigidity of the cell walls has led to low lipids release from microalgae cells due to difficulty in extracting the intracellular cell components, affecting other biofuels production processes. Due to this, several authors have suggested a pretreatment process as a means to disrupt the cell wall structure and improve degradation of microalgae. To determine the efficiency of microalgae pretreatment, a proper quantitative technique is useful to analyse cell disruption rate. This research began by comparing different pretreatment technologies using a light microscope. The light microscope was fitted with a Neubauer haemocytometer cell counter, in addition to the use of image-J cell counting software for visual analysis to quantify cell wall disruption using Chlorella vulgaris (C.vulgaris) as the model alga. C.vulgaris was selected as the microalgae species in this project as it has been widely established as a suitable species for biofuel production and anaerobic digestion due its dominance, being a local species in Australia, higher growth rates and higher lipids content when compared to other species. Pretreatment techniques compared included thermal processes using a water bath and autoclave, mechanical processing using a high-speed homogeniser, combinations of water bath and high-speed homogeniser as well as enzymatic pretreatment using lysozyme. The results of the experiments conducted showed over 80% cell disruption using high speed homogeniser and lysozyme enzyme. Thermal pretreatment using Autoclave produced the lowest cell disruption results at 42%. The results of the combination of water bath at roiling boil for 5 minutes and 5 minutes high speed homogeniser treatment at 4,000rpm showed a 50% cell disruption rate. For the water bath thermal pretreatment alone, 20 minutes was found to be most effective producing a 65% disruption rate. However, using microscopic analysis, although effective, is time-consuming for larger cell counts, making industrial pretreatment efficiency determination a challenge. Besides, the degree of pretreatment necessary to disrupt the cell is affected by the mechanical strength of the cell wall. Currently, there is little or no test for cell wall strength measurement that is shown to impact cell wall disruption and using anaerobic digestion to quantify cell strength can be slow due to long retention times. Understanding microalgae mechanical strength would enable better selection of microalgae pretreatment methods and improve energy production from microalgae, making it a more efficient process resulting in improvements in subsequent anaerobic digestion rates. From the study, a reproducible technique using high-speed homogeniser (at speeds between 4,000rpm to 33,000rpm) to evaluate the relative cell wall strength of C.vulgaris was developed and cell disruption was determined from lipid concentration following extraction. During the technique development, several solvents including diethyl ether, hexane and dichloromethane were investigated and compared for their use in extracting broken-only algae cells from solution. Dichloromethane proved to be the most suitable solvent for wet algae lipids extraction. From the results, it was determined that significant lipids extraction was from 8,500 rpm, which was identified -1 as the critical speed with shear rate of 18,227s . The maximum shear rate at 33,000rpm was found to -1 be 70,765s . Total lipids available in the cell was calculated using a modified Bligh and dyer method of dichloromethane to methanol of 2:1. It was found that the percentage of lipids from broken only cells compared to the total lipids in the cells was about a quarter at maximum cell disruption speed of 33,000rpm. Experimental verification was conducted using chlorophyll analysis and lysozyme addition which displayed a similar trend as the lipid extraction results show that the critical speed was also observed at 8,500rpm. Lysozyme enzymatic pretreatment was investigated for cell wall disruption and its impact in anaerobic hydrolysis as previous research had shown its ability to degrade C.vulgaris cells for biofuel processes. Lysozyme was later deduced in this project to initiate cell disruption, making further cell degradation by other hydrolytic enzymes easier, leading to improved lipids extraction and better anaerobic hydrolysis. The novel technique developed will assist biofuel technologies to determine the efficiency of microalgae pretreatment and has also provided knowledge on the critical shear rate when disruption occurs. Furthermore, microalgae cells showed resistance to microbial hydrolysis during previous anaerobic digestion studies using recovered microalgae from wastewater systems. Commercial anaerobic digestion using microalgae from wastewater utilises bacteria inoculum already present in the wastewater system. The effectiveness of this, however, has been low generating low yields of methane. Researching and identifying key micro-organisms in microalgae anaerobic digestion will promote the technology and improve bio-methane yields. To achieve this, bacteria such as Escherichia coli (E.coli), Streptococcus thermophilus (S.thermophilus), Lactobacillus plantarum (L.plantarum), Acetobacter aceti (A.aceti), as well as hydrolytic enzymes such as lysozyme, amylase, cellulase, pectinase, and Aspergillus oryzae (A.oryzae) fungus were utilised in separate and combined experiments’ to show the effectiveness of microbial selection and enzymes as inoculum for degrading C.vulgaris cell wall during anaerobic hydrolysis to produce volatile fatty acids (VFA) as intermediates. The amount of VFAs produced was used as a means of experimental process efficiency and to predict potential bio-methane production. Two separate experiment batches were conducted with batch 1 having retention times of 30, 45 and 60 days. Batch 2 had a retention time of 15 days as the results from batch 1 showed optimum VFA production at 30 days retention time. From the results, optimum total VFA concentration was obtained after 15 days retention using inoculum containing mixed enzymes (lysozyme, cellulase, pectinase and amylase) at 195 mg/l. This is followed by mixed bacteria containing E.coli, S.thermophilus and L.plantarum at total VFA concentration of 161 mg/l. Literature review on the selected bacteria shows the capability of these bacteria being able to produce the selected hydrolytic enzymes. Hence, the efficiency of the bacteria in producing total VFA results close to the values obtained from the mixed enzymes. Lowest VFA production was observed in test containing A.oryzae alone at 23mg/l. The low digestion efficiency observed from the fungus has been suggested to be as a result of the possibility of no cellulose wall detected in C.vulgaris cell. Another possibility is the aerobic property of the fungus limiting its growth efficiency during digestion. To investigate this further, C.vulgaris was flocculated with A.oryzae for 24 hours as well as 72 hours and used to harvest the microalgae. The harvested C.vulgaris cells were then subjected to high-speed homogeniser treatment using the technique developed earlier before undergoing anaerobic digestion using a retention time of 13 days with sampling every two days in a separate experiment. The initial tests involving harvesting of the microalgae by flocculation shows 72 hours to produce greater flocculation efficiency with almost 100% of the cells observed to flocculate and clump together under visual observation using a motic light microscope at 400X magnification. For the cell strength tests, 72-hours flocculated algae also displayed better performance with lipids extraction efficiency of 27% more than the control containing C.vulgaris alone. The 24-hour flocculated microalgae also showed good results with 20% more lipids production compared to the control containing C.vulgaris alone. However, when the flocculated microalgae at 72-hours was investigated for anaerobic hydrolysis, the results were again low providing only 14.7mg/l of total VFA at peak observed at day 5. The results confirm the earlier findings of the possibility of the absence of cellulose in the cell wall of C.vulgaris. Hence, the use of fungus A.oryzae maybe useful only in microalgae harvesting technology and not anaerobic digestion. In addition, the project provides a detailed energy calculation of the different pretreatment strategies employed and discussed the amount of energy consumed. Thermal pretreatment was found to have a lower energy consumption at 86kJ/L feed with energy recovery for both autoclave and waterbath compared. Also, without energy recovery, thermal pretreatment was still quite low at 497 kJ/feed for autoclave and 393 kJ/L feed for waterbath. Contrarily, high speed homogeniser was found to be energy intensive at maximum speed of 33000rpm with energy consumption of 1,080 kJ/L. However, at the critical speed of 8,500 rpm, energy consumption of the high speed homogeniser was low and close to thermal pretreatment with energy recovery utilising only 88.7 kJ/L feed. Moreover, potential biomethane to be produced from the optimum anaerobic hydrolysis experiment conducted at 15-days was evaluated. An energy balance and cost analysis were documented from the various biological and enzymatic pretreatments employed. A positive energy balance was observed across the various inoculum employed. Optimum net energy production was recorded by inoculum containing mixed enzymes (lysozyme, pectinase, cellulase and amylase) at 3362 J/L feed. This is followed by mixed bacteria (E.coli, S.thermophilus and L.plantarum) inoculum with net energy production at 2769.5 J/L feed. Investigating and proposing an effective method of microalgae digestion will enable microalgae disposal from wastewater and promote energy recovery making microalgal treatment of wastewater more likely in water and waste treatment facilities.

Automated short furrow irrigation (ASFI) is a prototype irrigation system that has the potential to be robust and relatively low-cost, with highly effective and efficient water use. ASFI has low energy requirements because the pressure at the field edge is relatively low, typically 70 kPa (or 7 m) as compared with approximately 150 kPa for drip and 400 kPa for dragline systems. However, at project onset, the only type of ASFI system tested was Microfurrow which was, among other problems, not robust. The aim of this project was, therefore, to develop, implement and evaluate a suitable ASFI system and to compare the system to a reference sub-surface drip (SSD) irrigation system with sugarcane as the test crop. This process resulted in the development of a boot and piston valve, which was used to automatically control the flow between specific plots. The valve was then implemented, as per design, in the ASFI system at a trial at the University of KwaZulu-Natal’s Ukulinga research farm. Irrigation events were scheduled according to SAsched with the aim of applying equivalent amounts of water to both the ASF and SSD treatments. The testing and evaluation included irrigation uniformity tests and the crop yields. Evaluation of selected furrows in the ASFI treatment showed a low quarter distribution uniformity (DUlq) range between 72 % and 80 %. This is considerably better than approximately 60 % for conventional furrow irrigation. However, the DU for ASFI could be improved to above 90 % if the slope was reduced from 1:40 to approximately 1:250. Both the harvested tons per hectare and sucrose content results were evaluated using a one-way statistical analysis with differences between the results deemed to be insignificant. Therefore, the ASFI performance in terms of harvest data for the Ukulinga trial could be described as “similar to” SSD irrigation. A 10 ha sample ASFI system was designed and compared in economic terms with a respective SSD system. Although further piping options can be explored in order to reduce the capital costs of the ASFI system even further, ASFI was considerably more cost-effective than the SSD system in terms of operating and fixed costs per hectare. The ASFI irrigation system, although having some initial maintenance requirements in insuring all furrows performed properly, required no other maintenance throughout the year in the Ukulinga trial. The drip system, however, required laterals to be flushed and leaks to be repaired. It is therefore believed that the ASFI system meets the required objectives of the project in that it is robust, low-cost (both operating and fixed) and able to supply water efficiently and effectively.
Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010.

Creativity is an ability with psychological and developmental benefits. Creative levels are dynamic and oscillate throughout life, with a first major decline occurring at the age of 7 years old. However, creativity is an ability that can be nurtured if trained, with evidence suggesting an increase in this ability with the use of validated creativity training. Yet, creativity training for young children (aged between 6-9 years old) appears as scarce. Additionally, existing training interventions resemble test-like formats and lack of playful dynamics that could engage children in creative practices over time. This PhD project aimed at contributing to creativity stimulation in children by proposing to use social robots as intervention tools, thus adding playful and interactive dynamics to the training. Towards this goal, we conducted three studies in schools, summer camps, and museums for children, that contributed to the design, fabrication, and experimental testing of a robot whose purpose was to re-balance creative levels. Study 1 (n = 140) aimed at testing the effect of existing activities with robots in creativity and provided initial evidence of the positive potential of robots for creativity training. Study 2 (n = 134) aimed at including children as co-designers of the robot, ensuring the robot’s design meets children’s needs and requirements. Study 3 (n = 130) investigated the effectiveness of this robot as a tool for creativity training, showing the potential of robots as creativity intervention tools. In sum, this PhD showed that robots can have a positive effect on boosting the creativity of children. This places social robots as promising tools for psychological interventions.
Criatividade é uma habilidade com benefícios no desenvolvimento saudável. Os níveis de criatividade são dinâmicos e oscilam durante a vida, sendo que o primeiro maior declínio acontece aos 7 anos de idade. No entanto, a criatividade é uma habilidade que pode ser nutrida se treinada e evidências sugerem um aumento desta habilidade com o uso de programas validados de criatividade. Ainda assim, os programas de criatividade para crianças pequenas (entre os 6-9 anos de idade) são escassos. Adicionalmente, estes programas adquirem o formato parecido ao de testes, faltando-lhes dinâmicas de brincadeira e interatividade que poderão motivar as crianças a envolverem-se em práticas criativas ao longo do tempo. O presente projeto de doutoramento procurou contribuir para a estimulação da criatividade em crianças propondo usar robôs sociais como ferramenta de intervenção, adicionando dinâmicas de brincadeira e interação ao treino. Assim, conduzimos três estudos em escolas, campos de férias, e museus para crianças que contribuíram para o desenho, fabricação, e teste experimental de um robô cujo objetivo é ser uma ferramenta que contribui para aumentar os níveis de criatividade. O Estudo 1 (n = 140) procurou testar o efeito de atividade já existentes com robôs na criatividade e mostrou o potencial positivo do uso de robôs para o treino criativo. O Estudo 2 (n = 134) incluiu crianças como co-designers do robô, assegurando que o desenho do robô correspondeu às necessidades das crianças. O Estudo 2 (n = 130) investigou a eficácia deste robô como ferramenta para a criatividade, demonstrando o seu potencial para o treino da criatividade. Em suma, o presente doutoramento mostrou que os robôs poderão ter um potencial criativo em atividades com crianças. Desta forma, os robôs sociais poderão ser ferramentas promissoras em intervenções na psicologia.

The small-scale wind energy generation system is one of the solutions to empower the isolated loads and provides a promising solution to decrease the greenhouse effect. This chapter describes the simulation analysis for wind energy conversion system incorporated with maximum power point tracking feature. The MPPT algorithms like variable current perturb and observe algorithm and variable step perturb and observe algorithm are incorporated with WECS. The comparative analysis is done in the closed-loop model in continuous time-varying wind speed. The closed-loop simulation is performed using a conventional fixed gain controller. To address the limitations of the fixed gain controller, the analysis is done using the gain scheduling proportional integral controller and the good gain method to tune the proportional integral controller. The comparative analysis between the fixed gain controller, the gain scheduling proportional integral controller, and the good gain method to tune proportional integral controller for above-stated MPPT methods is shown.

In this chapter, the authors primarily discuss how blockchain is being utilized in smarter grids across the globe and how some use cases can be a good fit as a technology. They ensure the reliability and uninterrupted power supply to end users by using smart metering in micro and macro grids, which is possible with novel technology that is transparent and without any cyberattacks/hackers: blockchain technology (BCT). In this chapter, BCT is implemented significantly at micro/macro smart grid network. Such a network would give efficient improvement and be interesting.

Dairying has become a major secondary source of income for several rural families. The easily perishable nature of milk increases the spoilage of the product and reduces the dairy farms' productivity in rural areas due to power supply shortage issues. In order to overcome the inaccessibility of proper preservation strategies, this chapter proposed a hybrid DC-DC converter for a solar battery-powered milk vending machine. This proposed system can work continuously and provides an uninterrupted power supply to maintain the milk quality at an optimum level. Moreover, the proposed system utilized a novel converter to reduce the number of power conversion stages and compact the system. Besides, the proposed converter can achieve a higher gain ratio with fewer components. Furthermore, a proper algorithmic-based control scheme has been implemented to maintain effective power flow management. Finally, to verify the feasibility and performance of the system, detailed results are obtained at different dynamic conditions, and various case studies are presented in this chapter.

The matrix converter (MC) has recently attracted significant attention among researchers because of its applications in wind energy conversion, military power supplies, induction motor drives, etc. Recently, different MC topologies have been proposed and developed which have their own advantages and disadvantages. Matrix converter can be classified as a direct and indirect structure. This chapter aims to give a general description of the basic features of a three phase to three phase matrix converters in terms of performance and of technological issues. Matrix converter is a direct AC-AC converter topology that is able to directly convert energy from an AC source to an AC load without the need of a bulky and limited lifetime energy storage element. AC-AC topologies receive extensive research attention for being an alternative to replace traditional AC-DC-AC converters in the variable voltage and variable frequency AC drive applications.

Until the middle of 20th century, there was a strong conviction that the next century would be the age of renewable and nuclear energy resources. However, at present, the whole world is dependent on fossil fuels to satisfy their energy need. Environmental pollution and global warming are the main issues associated with the use of fossil fuels for electricity generation. As per the report of US Energy Information IE Outlook 2016, coal, natural gas, and petroleum share nearly 67.2% of global electricity generation whereas renewable energy shares only 21.9%. This share is only one-fifth of the global electricity demand. According to the IEA 2016 Medium Term Renewable Energy Market Report, worldwide power production capacity of marine was only 539 MW in 2014, and to reach at a level of 640 MW, it will take 2021. The oceans cover about 70% of the Earth and acts as the largest thermal energy collector. A recent study reveals that global development capability of ocean energy is approximated to be 337 GW, and more than 885 TWH of electricity can be produced from this potential.

Application of multi-criteria decision analysis (MCDA) methods to various aspects of energy systems is of significant interest. This chapter first proposes a simple yet user-friendly MS-Excel tool with four popular MCDA methods. The tool can be effectively used to apply MCDA techniques and to determine the rankings for the alternatives. This MS-Excel tool is made available on Mendeley data repository. The chapter explains the overall MCDA computational processes, algorithms, and provides details on using the tool itself with the help of two case studies to demonstrate its effectiveness and applicability.

In this chapter, the author presents the operation and power management of the hydrogen storage-based smart DC microgrid (DCMG). In this microgrid, several renewable distributed generations (DGs) such as wind turbine, solar photovoltaic system, solid oxide fuel cell (SOFC), and battery energy storage system are interconnected together and to the various DC and AC loads to form a ring-type low voltage distribution network. An additional storage as Hydrogen storage system has been connected to the dc microgrid for balancing the power at all times in the DCMG, under islanded mode operation, for all practical cases. An architecture of the hydrogen storage-based DC microgrid is suggested mainly for the remote rural area. For the regeneration of the electricity from the stored hydrogen, a SOFC DG system is also used in the proposed DCMG. A control technique is also developed for the operation of the hydrogen storage-based DCMG. The proposed DCMG system provides a reliable and high-quality power supply and will supply the power to all loads (both DC and AC) simultaneously.

A method of optimization is used to resolve issues smartly by selecting the better option from various existing possibilities. Many optimization problems are possessing characteristics, namely nonlinearity, complexity, multimodal approach, and incompatible objective functions. Sometimes even for individual simple and linear type objective functions, a solution that is optimal and does not exist, there is uncertainness of obtaining the best solution. The aim of finding methods that can resolve various issues in a defined manner potentially has found the concentration of different researchers responsible for performing the advancement of a new “intelligent” technique called meta-heuristics technique. In the last few years, there is an advancement of various meta-heuristics techniques in different areas or various fields. Meta-heuristics are a demanded thrust stream of research that showed important advancement in finding the answer to problems that are optimized. The chapter gives the guidance for enhancing research more meaningfully.

Energy supply trends as well as environmental regulations and climate change issues have made it necessary to closely scrutinize the way energy is utilized. Efficient energy utilization thus requires paying more attention to accurate and advanced thermodynamic analysis of thermal systems. Hence, methods aimed at evaluating the performances of energy systems take into account the Energy, Environment and Economics. Therefore, the first and second law of thermodynamics combined with economics and environmental impact represents a very powerful tool for the systematic study and optimization of energy systems. In this study, a thermodynamic analysis of eleven selected gas turbine power plants in Nigeria was carried out using the first and second laws of thermodynamics, economic and environmental impact concepts. Exergetic, exergo-economic and exergo-environmental analyses were conducted using operating data obtained from the power plants to determine the exergy destruction and exergy efficiency of each major component of the gas turbine in each power plant. The exergy analysis confirmed that the combustion chamber is the most exergy destructive component compared to other cycle components as expected. The percentage exergy destruction in combustion chamber varied between 86.05 and 94.6%. Increasing the gas turbine inlet temperature (GTIT), the exergy destruction of this component can be reduced. Exergo-economic analysis showed that the cost of exergy destruction is high in the combustion chamber and by increasing the GTIT effectively decreases this cost. The exergy costing analysis revealed that the unit cost of electricity produced in the plants ranged from cents 1.88/kWh (₦2.99/kWh) to cents 5.65/kWh (₦8.98/kWh). Exergo-environmental analysis showed that the CO2 emissions varied between 100.18 to 408.78 kgCO2/MWh while cost rate of environmental impact varied from 40.18 $/h (N6, 388.62/h) to 276.97 $/h (N44, 038.23/h). The results further showed that CO2 emissions and cost of environmental impact decrease with increasing GTIT.

Aim/Purpose: [This Proceedings paper was revised and published in the 2018 issue of the journal Issues in Informing Science and Information Technology, Volume 15] This paper investigates the new technical skills that are needed for Data Engineering. Past research is compared to new research which creates a list of the 20 top tech-nical skills required by a Data Engineer. The growing availability of Data Engineering jobs is discussed. The research methodology describes the gathering of sample data and then the use of Pig and MapReduce on AWS (Amazon Web Services) to count occurrences of Data Engineering technical skills from 100 Indeed.com job advertisements in July, 2017. Background: A decade ago, Data Engineering relied heavily on the technology of Relational Database Management Sys-tems (RDBMS). For example, Grisham, P., Krasner, H., and Perry D. (2006) described an Empirical Soft-ware Engineering Lab (ESEL) that introduced Relational Database concepts to students with hands-on learning that they called “Data Engineering Education with Real-World Projects.” However, as seismic im-provements occurred for the processing of large distributed datasets, big data analytics has moved into the forefront of the IT industry. As a result, the definition for Data Engineering has broadened and evolved to include newer technology that supports the distributed processing of very large amounts of data (e.g. Hadoop Ecosystem and NoSQL Databases). This paper examines the technical skills that are needed to work as a Data Engineer in today’s rapidly changing technical environment. Research is presented that re-views 100 job postings for Data Engineers from Indeed (2017) during the month of July, 2017 and then ranks the technical skills in order of importance. The results are compared to earlier research by Stitch (2016) that ranked the top technical skills for Data Engineers in 2016 using LinkedIn to survey 6,500 peo-ple that identified themselves as Data Engineers. Methodology: A sample of 100 Data Engineering job postings were collected and analyzed from Indeed during July, 2017. The job postings were pasted into a text file and then related words were grouped together to make phrases. For example, the word “data” was put into context with other related words to form phrases such as “Big Data”, “Data Architecture” and “Data Engineering”. A text editor was used for this task and the find/replace functionality of the text editor proved to be very useful for this project. After making phrases, the large text file was uploaded to the Amazon cloud (AWS) and a Pig batch job using Map Reduce was leveraged to count the occurrence of phrases and words within the text file. The resulting phrases/words with occurrence counts was download to a Personal Computer (PC) and then was loaded into an Excel spreadsheet. Using a spreadsheet enabled the phrases/words to be sorted by oc-currence count and then facilitated the filtering out of irrelevant words. Another task to prepare the data involved the combination phrases or words that were synonymous. For example, the occurrence count for the acronym ELT and the occurrence count for the acronym ETL were added together to make an overall ELT/ETL occurrence count. ETL is a Data Warehousing acronym for Extracting, Transforming and Loading data. This task required knowledge of the subject area. Also, some words were counted in lower case and then the same word was also counted in mixed or upper case, thus producing two or three occur-rence counts for the same word. These different counts were added together to make an overall occur-rence count for the word (e.g. word occurrence counts for Python and python were added together). Fi-nally, the Indeed occurrence counts were sorted to allow for the identification of a list of the top 20 tech-nical skills needed by a Data Engineer. Contribution: Provides new information about the Technical Skills needed by Data Engineers. Findings: Twelve of the 20 Stitch (2016) report phrases/words that are highlighted in bold above matched the tech-nical skills mentioned in the Indeed research. I considered C, C++ and Java a match to the broader cate-gory of Programing in the Indeed data. Although the ranked order of the two lists did not match, the top five ranked technical skills for both lists are similar. The reader of this paper might consider the skills of SQL, Python, Hadoop/HDFS to be very important technical skills for a Data Engineer. Although the programming language R is very popular with Data Scientists, it did not make the top 20 skills for Data Engineering; it was in the overall list from Indeed. The R programming language is oriented towards ana-lytical processing (e.g. used by Data Scientists), whereas the Python language is a scripting and object-oriented language that facilitates the creation of Data Pipelines (e.g. used by Data Engineers). Because the data was collected one year apart and from very different data sources, the timing of the data collection and the different data sources could account for some of the differences in the ranked lists. It is worth noting that the Indeed research ranked list introduced the technical skills of Design Skills, Spark, AWS (Amazon Web Services), Data Modeling, Kafta, Scala, Cloud Computing, Data Pipelines, APIs and AWS Redshift Data Warehousing to the top 20 ranked technical skills list. The Stitch (2016) report that did not have matches to the Indeed (2017) sample data for Linux, Databases, MySQL, Business Intelligence, Oracle, Microsoft SQL Server, Data Analysis and Unix. Although many of these Stitch top 20 technical skills were on the Indeed list, they did not make the top 20 ranked technical skills. Recommendations for Practitioners: Some of the skills needed for Database Technologies are transferable to Data Engineering. Recommendation for Researchers: None Impact on Society: There is not much peer reviewed literature on the subject of Data Engineering, this paper will add new information to the subject area. Future Research: I'm developing a Specialization in Data Engineering for the MS in Data Science degree at our university.

The new generation State Test House Brix/Acid test system, is a bold integration of open platform, personal computer and process controller instrumentation and software sub-systems designed to maximize the efficiency and utilization of existing automatic fruit analyzer hardware. The new equipment provides cost-effective, state-of-the-art hardware connectivity and software programmability. The new generation of test house equipment is a recombination of basic industry approved automatic fruit analysis, test hardware and procedures. The scope of modernization and renovation included system rewiring, incorporation of a programmable controller, a new test computer, UNIX operating system, supervisory control and data acquisition (SCADA) software, a fourth generation relational data base, communications system, and a central office host computer. A new environmental systems enclosure, new weight controllers, sample scale, Super VGA color monitor, pH and temperature sensing instrumentation, multi-form printers, and 9600 baud modems were also furnished. The method of testing for Brix and acid remained intact. Paper published with permission.

Abstract A computer aided analysis of a heavy duty fabricated gear wheel is presented. The concept of CYCLIC SYMMETRY and the SKYLINE APPROACH are exploited to reduce the computer memory and time. Static and Eigen value analyses are conducted. This is followed by a Quasi Static analysis which gives an idea of the Dynamic behaviour of the gear wheel. The emphasis has been on the use of the PC for solving this industrial problem.

Increasing attention has recently been drawn to the energy consumption of the manufacturing process. Facing the challenges from reducing emission, rising raw material prices and energy costs, manufacturers are trying to balance the energy usage strategy among the total energy consumption, economy and environment, which can be self-conflicting at times. This paper focuses on the objective optimizations of a plant level energy supply system, and describes how a multi-objective optimization strategy can be effectively formulated for making the best use of energy delivered to the manufacturing process. An example from an automotive assembly manufacturer is described.

The Arnold Engineering Development Center (AEDC) is installing a freejet test capability into the Aero-propulsion Systems Test Facility (ASTF). The freejet will provide the capability for ground determination of turbine engine and aircraft inlet compatibility by utilizing full-scale inlets and engines as test articles in a simulated flight environment. The details of the design, installation, and projected testing capability are described for a 57 ft2 supersonic nozzle and a 77 ft2 subsonic nozzle. Support systems for mechanically pitching and yawing the freejet nozzles are also reported as well as the test cell hardware for capturing the freejet nozzle flow. The plans for demonstrating the freejet capability prior to its initial operational date are explained. The technology development efforts to validate and utilize the freejet test capabilities are also described.