This study focuses on the modelling and simulation of an existing active forced circulation solar water heating system in the College of Science and Technology under the Royal University of Bhutan. The installed prototype solar system consists of five flat-panel collectors connected in parallel, with a gross surface area of 10 m2, and a 500-litre water storage tank with a built-in heat exchanger to preheat the water in the student mess. The TRNSYS (Transient System Simulation Software) program is used to model and simulate an identical replica of the installed system. The simulation model is validated by comparing the simulation results with actual measurements. The effects of hot tank temperature and stagnation are simulated. When the temperature of the hot tank reaches a preset value of 60 °C, the circulation pump is turned off, causing the temperature of the solar collector to increase exponentially to stagnation. However, by increasing the hot tank set temperature to 80 ˚C, the stagnation time could be extended by two hours, during which the system can generate 25.425 kWh of thermal energy, while 60 ˚C provides only 18.45 kWh. The overall efficiency of the system increased from 27.13% to 37.88%.
{"title":"THE EFFECT OF PRESET STORAGE TANK TEMPERATURE ON THE STAGNATION OF A FORCED CIRCULATION TYPE SOLAR WATER HEATING SYSTEM","authors":"K. Wangchuk, C. Dorji, Dr. Tshewang Lhendup","doi":"10.54417/jaetm.v2i1.60","DOIUrl":"https://doi.org/10.54417/jaetm.v2i1.60","url":null,"abstract":"This study focuses on the modelling and simulation of an existing active forced circulation solar water heating system in the College of Science and Technology under the Royal University of Bhutan. The installed prototype solar system consists of five flat-panel collectors connected in parallel, with a gross surface area of 10 m2, and a 500-litre water storage tank with a built-in heat exchanger to preheat the water in the student mess. The TRNSYS (Transient System Simulation Software) program is used to model and simulate an identical replica of the installed system. The simulation model is validated by comparing the simulation results with actual measurements. The effects of hot tank temperature and stagnation are simulated. When the temperature of the hot tank reaches a preset value of 60 °C, the circulation pump is turned off, causing the temperature of the solar collector to increase exponentially to stagnation. However, by increasing the hot tank set temperature to 80 ˚C, the stagnation time could be extended by two hours, during which the system can generate 25.425 kWh of thermal energy, while 60 ˚C provides only 18.45 kWh. The overall efficiency of the system increased from 27.13% to 37.88%.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89237335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Y. Tenzin, Sonam Tenzin, Pema Choden, Kencho Gyem, K. Phuntsho, S. Chophel, T. Dorji, Chimmi
Abstract: Porous concrete for low-impact development has long been studied for the improvement of urban stormwater management. However, the porous concrete made using Recycled Concrete Aggregate (RCA) is still lacking, particularly concerning its strength and infiltration rates. Therefore, this paper aimed to design porous concrete using RCA with optimum infiltration rate without compromising the strength. To fulfill this aim, a laboratory study evaluating the strength and infiltration characteristics of a porous concrete mix is presented. From the mixed design 1: 0.4: 3.6 (Portland Pozzolana Cement (PPC): natural sand: natural coarse aggregate), Natural Coarse Aggregate (NCA) is partially replaced by RCA in the interval of 0%, 15%, 30%, and 45% to find the optimum infiltration without compromising the strength. The 10 mm aggregate is used as it was recorded for the highest compressive strength after curing for 28 days. With the increase in the addition of RCA, the compressive strength decreases whereas the infiltration rate increases. From the comparative study of infiltration rate and compressive strength, 30% replacement of NCA with RCA in the ratio of 1:0.4:1.08:2.52 (cement: fine aggregate: RCA: NCA) is found to give the most satisfactory result with infiltration rate and compressive strength of 9737 mm/hr and 8.67 MPa respectively. The water quality test is conducted to evaluate whether the porous concrete detention system can reduce the pollutants from the surface run-off. The pH and acidity parameters are considered to check the quality of stormwater. Stormwater after infiltrating through the prototype becomes basic in nature.
{"title":"EVALUATION OF STRENGTH AND INFILTRATION CHARACTERISTICS OF POROUS CONCRETE MADE USING RECYCLED CONCRETE AGGREGATE","authors":"R. Y. Tenzin, Sonam Tenzin, Pema Choden, Kencho Gyem, K. Phuntsho, S. Chophel, T. Dorji, Chimmi","doi":"10.54417/jaetm.v2i1.57","DOIUrl":"https://doi.org/10.54417/jaetm.v2i1.57","url":null,"abstract":"Abstract: Porous concrete for low-impact development has long been studied for the improvement of urban stormwater management. However, the porous concrete made using Recycled Concrete Aggregate (RCA) is still lacking, particularly concerning its strength and infiltration rates. Therefore, this paper aimed to design porous concrete using RCA with optimum infiltration rate without compromising the strength. To fulfill this aim, a laboratory study evaluating the strength and infiltration characteristics of a porous concrete mix is presented. From the mixed design 1: 0.4: 3.6 (Portland Pozzolana Cement (PPC): natural sand: natural coarse aggregate), Natural Coarse Aggregate (NCA) is partially replaced by RCA in the interval of 0%, 15%, 30%, and 45% to find the optimum infiltration without compromising the strength. The 10 mm aggregate is used as it was recorded for the highest compressive strength after curing for 28 days. With the increase in the addition of RCA, the compressive strength decreases whereas the infiltration rate increases. From the comparative study of infiltration rate and compressive strength, 30% replacement of NCA with RCA in the ratio of 1:0.4:1.08:2.52 (cement: fine aggregate: RCA: NCA) is found to give the most satisfactory result with infiltration rate and compressive strength of 9737 mm/hr and 8.67 MPa respectively. The water quality test is conducted to evaluate whether the porous concrete detention system can reduce the pollutants from the surface run-off. The pH and acidity parameters are considered to check the quality of stormwater. Stormwater after infiltrating through the prototype becomes basic in nature.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"104 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77122275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Drakpa Wangdi, C. Dorji, Gom Dorji, Dr. Ugyen Dorji
Renewable energy is seen as a potential option to offset the rate at which natural resources are being depleted. As a result, investment and development of renewable energy sources such as wind, solar and biogas have grown substantially. While wind and solar are being used more efficiently as technology advances rapidly, and the research and application of biogas production are also being explored. Biogas is a green energy source produced from the decomposition of organic materials such as food waste and animal manure. In this study, the potential for bench-scale biogas production was investigated using boiled rice wastewater as the primary feedstock. Considering parameters such as ambient temperature, control temperature, and pH of the feedstock, three experimental setups were carried out. The findings suggest the potential of biogas from boiled rice wastewater as the primary raw material. Temperature, pH, and HRT are all important factors in biogas production. This study observed that boiled rice wastewater feed could generate 2.97 liters of biogas per litre of raw material.
{"title":"A BENCH-SCALE STUDY ON POTENTIAL BIOGAS PRODUCTION FROM BOILED RICE WASTEWATER","authors":"Drakpa Wangdi, C. Dorji, Gom Dorji, Dr. Ugyen Dorji","doi":"10.54417/jaetm.v2i1.54","DOIUrl":"https://doi.org/10.54417/jaetm.v2i1.54","url":null,"abstract":"Renewable energy is seen as a potential option to offset the rate at which natural resources are being depleted. As a result, investment and development of renewable energy sources such as wind, solar and biogas have grown substantially. While wind and solar are being used more efficiently as technology advances rapidly, and the research and application of biogas production are also being explored. Biogas is a green energy source produced from the decomposition of organic materials such as food waste and animal manure. In this study, the potential for bench-scale biogas production was investigated using boiled rice wastewater as the primary feedstock. Considering parameters such as ambient temperature, control temperature, and pH of the feedstock, three experimental setups were carried out. The findings suggest the potential of biogas from boiled rice wastewater as the primary raw material. Temperature, pH, and HRT are all important factors in biogas production. This study observed that boiled rice wastewater feed could generate 2.97 liters of biogas per litre of raw material.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79169167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Choden, Sonam, Sherub Tenzin, Karchung, Yeshi Seldon
The power system should ensure safe and consistent power to the customer. For secure operation, the voltage should be within the desired limits, or else it will result in voltage collapse and power losses. The power system will be more competent, economic, reliable, and reduce power losses if the voltage stability is enhanced. Since the voltage stability is determined by the reactive power of the network, a reactive power source should be provided to safeguard the stability of the power system. This paper presents the enhancement of voltage stability in the power system using a Genetic Algorithm (GA). The GA approach is used to find the optimal value of control variables such as generator bus voltage, shunt capacitance, and transformer tap setting which are the source of reactive power. The GA was executed via MATLAB programming with MATPOWER. The propounded method was tested on the western grid of Bhutan to minimize the real power losses. The results demonstrate improved voltage stability in the power system and a significant reduction in power losses. The results will help Power System Operators to make a better decision while encountering voltage issues in their power lines. Moreover, this research will guide future research in dealing with similar research especially in calculating the optimal location of FACT devices for reactive power compensation.
{"title":"ENHANCEMENT OF VOLTAGE STABILITY IN THE POWER SYSTEM USING GENETIC ALGORITHM","authors":"K. Choden, Sonam, Sherub Tenzin, Karchung, Yeshi Seldon","doi":"10.54417/jaetm.v2i1.59","DOIUrl":"https://doi.org/10.54417/jaetm.v2i1.59","url":null,"abstract":"The power system should ensure safe and consistent power to the customer. For secure operation, the voltage should be within the desired limits, or else it will result in voltage collapse and power losses. The power system will be more competent, economic, reliable, and reduce power losses if the voltage stability is enhanced. Since the voltage stability is determined by the reactive power of the network, a reactive power source should be provided to safeguard the stability of the power system. This paper presents the enhancement of voltage stability in the power system using a Genetic Algorithm (GA). The GA approach is used to find the optimal value of control variables such as generator bus voltage, shunt capacitance, and transformer tap setting which are the source of reactive power. The GA was executed via MATLAB programming with MATPOWER. The propounded method was tested on the western grid of Bhutan to minimize the real power losses. The results demonstrate improved voltage stability in the power system and a significant reduction in power losses. The results will help Power System Operators to make a better decision while encountering voltage issues in their power lines. Moreover, this research will guide future research in dealing with similar research especially in calculating the optimal location of FACT devices for reactive power compensation.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79349005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Net Present Value (NPV), Internal Rate of Return (IRR), and Depreciation Methods are employed in most engineering projects to visualize the true potential of Return on Investment (ROI) in today’s capital investment world. Most previous studies have appreciated and indicated the usefulness of each method in determining economically feasible projects. However, some previous studies have applied all methods without a proper distinction between budgeting and accounting concepts and lacked insights into various situations under which each method has differed. This paper aims to explore the circumstances in which all methods differ to determine the most economically and optimal project alternatives. It describes a thematic literature review of the past 17 articles like the peer-reviewed conference and journal articles published from 1969 through 2021. The articles with citations have been randomly selected to analyze the data. The results indicate that the three methods are commonly used in all engineering projects under certain conditions. It concludes that NPV and IRR are capital budgeting methods based on discounted cash flow methods while depreciation is the accounting method based on non-cash discounted methods. The results also demonstrate that different depreciation methods are also employed throughout the project evaluation process to determine the best project alternatives. For an engineer to produce the results and make effective investment decisions, estimating the cost, predicting the savings, and acclimatizing to the budgeting and accounting concepts are crucial under each method.
{"title":"APPLICATION OF DEPRECIATION NET PRESENT VALUE AND INTERNAL RATE OF RETURN IN ENGINEERING PROJECTS A BRIEF LITERATURE REVIEW","authors":"Pema Wangchuk","doi":"10.54417/jaetm.v2i1.55","DOIUrl":"https://doi.org/10.54417/jaetm.v2i1.55","url":null,"abstract":"The Net Present Value (NPV), Internal Rate of Return (IRR), and Depreciation Methods are employed in most engineering projects to visualize the true potential of Return on Investment (ROI) in today’s capital investment world. Most previous studies have appreciated and indicated the usefulness of each method in determining economically feasible projects. However, some previous studies have applied all methods without a proper distinction between budgeting and accounting concepts and lacked insights into various situations under which each method has differed. This paper aims to explore the circumstances in which all methods differ to determine the most economically and optimal project alternatives. It describes a thematic literature review of the past 17 articles like the peer-reviewed conference and journal articles published from 1969 through 2021. The articles with citations have been randomly selected to analyze the data. The results indicate that the three methods are commonly used in all engineering projects under certain conditions. It concludes that NPV and IRR are capital budgeting methods based on discounted cash flow methods while depreciation is the accounting method based on non-cash discounted methods. The results also demonstrate that different depreciation methods are also employed throughout the project evaluation process to determine the best project alternatives. For an engineer to produce the results and make effective investment decisions, estimating the cost, predicting the savings, and acclimatizing to the budgeting and accounting concepts are crucial under each method.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74989116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The water balance of a watershed is critical for the estimation of the water budget to meet the present and future domestic and economic demand and supply of water. Water balance parameters like precipitation, temperature, evapotranspiration soil moisture content deficit and surplus determine the water budget of a watershed which is further influenced by factors like land use, soil types, seasonal variation and other environmental factors. This paper intends to estimate the water balance of the Barsachhu watershed using Thornthwaite and Mather (TM) model. The use of Remote Sensing data and GIS as a tool were used in deriving the required data in executing the model. The study indicates that the monthly soil moisture content (deficit or surplus) is substantially influenced by the change in monthly rainfall, temperature and land use land cover pattern. April to October remain water surplus months while November to March remains a period of deficit. The soil moisture content has a different response to different land use in the Barsachhu watershed. The maximum annual moisture deficit and surplus of the basin are 126.27 mm and 2430.79 mm respectively and is observed in built-up areas. The runoff coefficient of the Barsachhu watershed computed from the runoff simulation of the TM model is 0.63.
流域的水平衡对于估计满足当前和未来国内和经济用水需求和供应的水预算至关重要。降水、温度、蒸散等水分平衡参数决定了流域的水分收支，而流域的水分收支又受到土地利用、土壤类型、季节变化等环境因素的影响。本文拟采用Thornthwaite and Mather (TM)模型对Barsachhu流域的水平衡进行估算。利用遥感数据和地理信息系统作为工具，导出执行模型所需的数据。研究表明，月土壤水分含量(亏余)受月降雨量、月温度和土地利用、土地覆盖格局变化的显著影响。4月至10月仍然是水资源过剩的月份，而11月至3月仍然是水资源短缺的时期。Barsachhu流域土壤含水量对不同土地利用方式的响应不同。流域年最大水分亏缺和盈余分别为126.27 mm和2430.79 mm，主要分布在建成区。TM模型径流模拟计算的Barsachhu流域径流系数为0.63。
{"title":"ESTIMATION OF WATER BALANCE OF BARSACHHU WATERSHED IN CHUKHA BHUTAN USING REMOTE SENSING AND GIS","authors":"Gautam Thapa, Kaushila Timshina, Krishna Kumar Subedi","doi":"10.54417/jaetm.v2i1.53","DOIUrl":"https://doi.org/10.54417/jaetm.v2i1.53","url":null,"abstract":"The water balance of a watershed is critical for the estimation of the water budget to meet the present and future domestic and economic demand and supply of water. Water balance parameters like precipitation, temperature, evapotranspiration soil moisture content deficit and surplus determine the water budget of a watershed which is further influenced by factors like land use, soil types, seasonal variation and other environmental factors. This paper intends to estimate the water balance of the Barsachhu watershed using Thornthwaite and Mather (TM) model. The use of Remote Sensing data and GIS as a tool were used in deriving the required data in executing the model. The study indicates that the monthly soil moisture content (deficit or surplus) is substantially influenced by the change in monthly rainfall, temperature and land use land cover pattern. April to October remain water surplus months while November to March remains a period of deficit. The soil moisture content has a different response to different land use in the Barsachhu watershed. The maximum annual moisture deficit and surplus of the basin are 126.27 mm and 2430.79 mm respectively and is observed in built-up areas. The runoff coefficient of the Barsachhu watershed computed from the runoff simulation of the TM model is 0.63.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78648713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hydropower has been the primary source of electricity in Bhutan, and to achieve power security and sustainability, alternative renewable energy sources (RES) such as solar and wind are being explored. However, the literature reviews present that bus voltage is the most affected parameter during integration. Therefore, this paper presents the impact on the bus voltage due integration of RES into the power network of Bhutan. The measured weather and power grid parameters were used as inputs to the solar and wind farm models developed in MATLAB/Simulink. The output from Simulink was then used as input to the solar and wind model in DIgSILENT Power Factory. The existing Bhutan power grid from 33kV and above has been developed in DIgSILENT to study power flow and results were validated against relevant standards. The voltage profile at the individual bus was maintained at 0.95 to 1.05 p.u. The varying hourly load for 24 hours at the different substations was considered. A quasi-dynamic simulation was performed to study the impact on voltage stability of buses at different penetration levels with every 5% increment. It was observed that at a 25% penetration level, the voltage falls below the accepted limit of 0.95 p.u. The Levelised Cost of Energy for the wind was calculated to be Nu. 13.37/ kWh and Nu. 6.02/ kWh and Nu. 6.51/ kWh from Shingkhar and Yongtru solar, respectively.
{"title":"IMPACTS OF INTEGRATING SOLAR AND WIND PLANTS INTO THE POWER NETWORK OF BHUTAN","authors":"Amir Subba, Dr. Tshewang Lhendup, R. Chhetri","doi":"10.54417/jaetm.v2i1.58","DOIUrl":"https://doi.org/10.54417/jaetm.v2i1.58","url":null,"abstract":"Hydropower has been the primary source of electricity in Bhutan, and to achieve power security and sustainability, alternative renewable energy sources (RES) such as solar and wind are being explored. However, the literature reviews present that bus voltage is the most affected parameter during integration. Therefore, this paper presents the impact on the bus voltage due integration of RES into the power network of Bhutan. The measured weather and power grid parameters were used as inputs to the solar and wind farm models developed in MATLAB/Simulink. The output from Simulink was then used as input to the solar and wind model in DIgSILENT Power Factory. The existing Bhutan power grid from 33kV and above has been developed in DIgSILENT to study power flow and results were validated against relevant standards. The voltage profile at the individual bus was maintained at 0.95 to 1.05 p.u. The varying hourly load for 24 hours at the different substations was considered. A quasi-dynamic simulation was performed to study the impact on voltage stability of buses at different penetration levels with every 5% increment. It was observed that at a 25% penetration level, the voltage falls below the accepted limit of 0.95 p.u. The Levelised Cost of Energy for the wind was calculated to be Nu. 13.37/ kWh and Nu. 6.02/ kWh and Nu. 6.51/ kWh from Shingkhar and Yongtru solar, respectively.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86995233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Power demand is expanding day by day. The greatest test is to give continuous and top-notch power to clients in factor conditions particularly when we interconnect the two areas utilizing power tie-line. To achieve this, the two boundaries should consistently be checked for each condition, these boundaries are Load Distribution and Load Frequency Control (LFC).The primary work of the load frequency control is to regulate the power output of the generator within a specified area with respect to change in system frequency and tie-line power, such as to maintain the scheduled system frequency and power interchange with other areas in a prescribed limit [1][2]. In this paper, the study of LFC system for two areas consisting of Hydropower Plant and Wind Power Plant are carried out. The fuzzy gain scheduled proportional-integral (FGSPI) and fuzzy gain scheduled proportional integral derivative (FGSPID) controllers are designed for load frequency control (LFC) of a two-area interconnected power system. The proposed FGSPI and FGSPID controllers are compared against conventional proportional-integral (PI) controllers and Proportional integral derivation (PID) controllers concerning settling times and peak overshoots of the tie-line power and frequency deviations as performance indices. Comparative analysis indicates that the proposed intelligent controller gives better performance than conventional controllers. Simulations have been performed using Simulink toolbox in MATLAB.
{"title":"LOAD FREQUENCY CONTROL OF INTERCONNECTED POWER SYSTEM GRID INVOLVING WIND AND HYDROPOWER PLANT AND COMPARATIVE ANALYSIS","authors":"P. Rai, Bikram Chhetri, Chimi Dem, Khalishore Chhetri, Phuntshog Tashi, Sanjita Lepcha","doi":"10.54417/jaetm.v1i1.23","DOIUrl":"https://doi.org/10.54417/jaetm.v1i1.23","url":null,"abstract":"Power demand is expanding day by day. The greatest test is to give continuous and top-notch power to clients in factor conditions particularly when we interconnect the two areas utilizing power tie-line. To achieve this, the two boundaries should consistently be checked for each condition, these boundaries are Load Distribution and Load Frequency Control (LFC).The primary work of the load frequency control is to regulate the power output of the generator within a specified area with respect to change in system frequency and tie-line power, such as to maintain the scheduled system frequency and power interchange with other areas in a prescribed limit [1][2]. In this paper, the study of LFC system for two areas consisting of Hydropower Plant and Wind Power Plant are carried out. The fuzzy gain scheduled proportional-integral (FGSPI) and fuzzy gain scheduled proportional integral derivative (FGSPID) controllers are designed for load frequency control (LFC) of a two-area interconnected power system. The proposed FGSPI and FGSPID controllers are compared against conventional proportional-integral (PI) controllers and Proportional integral derivation (PID) controllers concerning settling times and peak overshoots of the tie-line power and frequency deviations as performance indices. Comparative analysis indicates that the proposed intelligent controller gives better performance than conventional controllers. Simulations have been performed using Simulink toolbox in MATLAB.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74177470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Millions of users worldwide use VPN clients to either circumvent censorship or to access geo-blocked content, and specifically for privacy and security purposes. In the pretext of secured communication and privacy, numerous free android-based VPNs are being pushed up in the Google Play store. However, the users aren’t sure or aware of whether the VPN is truly secure or just leaking their data. So, the forensic and behavior analysis of selected free android VPNs was carried out to study the usability of free android-based VPNs in terms of providing security and privacy; specifically, the presence of dangerous permissions, malware presence, traffic encryption, the DNS leaks, and the possibility of leaving forensic artifacts on the device after the VPN use. The study revealed considerable portion of the sample free VPNs were flagged malicious and had dangerous levels of permissions in use. While some failed the DNS leak test and some VPNs even did not encrypt the traffic. Given the availability of a huge number of Free VPNs in the Google Play store, it was found important that the users must be aware of the inherent risks put by the use of these Free VPNs.
{"title":"FORENSIC AND BEHAVIOR ANALYSIS OF FREE ANDROID VPNS","authors":"T. Wangchuk, Digvijaysingh Rathod","doi":"10.54417/jaetm.v1i1.27","DOIUrl":"https://doi.org/10.54417/jaetm.v1i1.27","url":null,"abstract":"Millions of users worldwide use VPN clients to either circumvent censorship or to access geo-blocked content, and specifically for privacy and security purposes. In the pretext of secured communication and privacy, numerous free android-based VPNs are being pushed up in the Google Play store. However, the users aren’t sure or aware of whether the VPN is truly secure or just leaking their data. So, the forensic and behavior analysis of selected free android VPNs was carried out to study the usability of free android-based VPNs in terms of providing security and privacy; specifically, the presence of dangerous permissions, malware presence, traffic encryption, the DNS leaks, and the possibility of leaving forensic artifacts on the device after the VPN use. The study revealed considerable portion of the sample free VPNs were flagged malicious and had dangerous levels of permissions in use. While some failed the DNS leak test and some VPNs even did not encrypt the traffic. Given the availability of a huge number of Free VPNs in the Google Play store, it was found important that the users must be aware of the inherent risks put by the use of these Free VPNs.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84967286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study focuses on efficient lighting design in Jigme Namgyel Engineering College (JNEC), under the Royal University of Bhutan (RUB). To carry out the detailed study and review of the existing lighting scheme, Relux simulation software was used and it is one of the high-performance software to simulate electric and daylight for illumination design and study. The study was based on the existing lighting scheme and a comparative study employing different luminaires (fluorescent lamp and LED) was performed succeeded by designing an efficient illumination lighting scheme. Further to increase energy saving during the daytime, daylight has been integrated with all the lighting schemes studied. The simulation result exhibits that the average illuminance for the existing lighting scheme is 161lx which does not meet the standard lx level for given infrastructures. Two new lighting schemes using fluorescent lamps and LED lamps were suggested following the standard lx level recommended at the workplace. The comparative life cycle cost analysis of the proposed lighting scheme resulted in 59.9% energy saving potential and accounted for a payback period of 2years when employing LED lamps instead of existing illumination fixtures.
{"title":"ENERGY EFFICIENT LIGHTING DESIGN - A CASE STUDY OF JIGME NAMGYEL ENGINEERING COLLEGE","authors":"Karma Yangzom, Hemlal Bhattarai, Sonam Choki, Pema Choden, Sonam Yangden","doi":"10.54417/jaetm.v1i1.20","DOIUrl":"https://doi.org/10.54417/jaetm.v1i1.20","url":null,"abstract":"This study focuses on efficient lighting design in Jigme Namgyel Engineering College (JNEC), under the Royal University of Bhutan (RUB). To carry out the detailed study and review of the existing lighting scheme, Relux simulation software was used and it is one of the high-performance software to simulate electric and daylight for illumination design and study. \u0000The study was based on the existing lighting scheme and a comparative study employing different luminaires (fluorescent lamp and LED) was performed succeeded by designing an efficient illumination lighting scheme. Further to increase energy saving during the daytime, daylight has been integrated with all the lighting schemes studied. The simulation result exhibits that the average illuminance for the existing lighting scheme is 161lx which does not meet the standard lx level for given infrastructures. Two new lighting schemes using fluorescent lamps and LED lamps were suggested following the standard lx level recommended at the workplace. The comparative life cycle cost analysis of the proposed lighting scheme resulted in 59.9% energy saving potential and accounted for a payback period of 2years when employing LED lamps instead of existing illumination fixtures.","PeriodicalId":38544,"journal":{"name":"Journal of Technology, Management, and Applied Engineering","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82371697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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