European Journal of Engineering Research and Science最新文献

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Next Steps Might Be Considered by Joe Biden for the Development of International Trade Law 乔·拜登可能考虑下一步发展国际贸易法
European Journal of Engineering Research and Science Pub Date : 2020-11-25 DOI: 10.24018/ejers.2020.5.11.2234
Md. Habib Alam
{"title":"Next Steps Might Be Considered by Joe Biden for the Development of International Trade Law","authors":"Md. Habib Alam","doi":"10.24018/ejers.2020.5.11.2234","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2234","url":null,"abstract":"The United States of America is a part of the globalization of international trade law. The USA is known as a leading global trader among all nations. The President of the USA plays a vital role in the development of international trade law. On 8 November 2016, Donald Trump was elected as president of the United States of America. Donald Trump engaged in different trade deals and policies with different countries and international institutions. The trade deals and policies are withdrawal from TPP, reshaping NAFTA, reforming WTO, and imposing tariffs on foreign goods. On 8 November 2020, CNN commented, Joe Biden will be the next president of the USA. Many scholars expressed different thoughts relating to the reforming international trade law by Joe Biden. The main aim of Joe Biden will be to remove trade barriers and end artificial trade wars with different foreign nations. My research will suggest how Joe Biden may overcome these issues for the betterment of the international trade law around the world.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90375844","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}
引用次数: 0
Maximally Flat IIR Fullband Differentiators with Flat Group Delay Responses 具有平坦群延迟响应的最大平坦IIR全带微分器
European Journal of Engineering Research and Science Pub Date : 2020-11-25 DOI: 10.24018/ejers.2020.5.11.2238
S. Ilić, A. M. Salih, Majid Hamid Abdullah, Dragiša Milić
{"title":"Maximally Flat IIR Fullband Differentiators with Flat Group Delay Responses","authors":"S. Ilić, A. M. Salih, Majid Hamid Abdullah, Dragiša Milić","doi":"10.24018/ejers.2020.5.11.2238","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2238","url":null,"abstract":"A new design method for maximally flat IIR fullband differentiators with flat group delay responses is derived in this paper. The design method starts from the flatness conditions of magnitude response and group delay response at the origin. After mathematical manipulations it shows that presented design method reduces to solving the system of linear equations. By increasing the orders of polynomials in numerator and denominator, degrees of flatness are increased, that is improvement in magnitude responses and group delay responses in terms of flatness is obtained.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"85 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81194553","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}
引用次数: 1
Preliminary Re-design of an Axial Turbine in an Existing Engine to Meet the Increased Load Demand 在现有发动机上对轴向涡轮进行初步重新设计以满足增加的负荷需求
European Journal of Engineering Research and Science Pub Date : 2020-11-24 DOI: 10.24018/ejers.2020.5.11.2141
R. Agbadede, Dennis Uwakwe, I. Allison
{"title":"Preliminary Re-design of an Axial Turbine in an Existing Engine to Meet the Increased Load Demand","authors":"R. Agbadede, Dennis Uwakwe, I. Allison","doi":"10.24018/ejers.2020.5.11.2141","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2141","url":null,"abstract":"This work presents a preliminary design of an axial turbine section in an industrial gas turbine. The design was necessitated following the need to provide a gas turbine of a power output in the range of 48 to 60MW for a mini-city harbouring an oil rig, which was not possible with the old engine. The turbine section is designed to produce a power capable of driving the compressor as well as produce a useful power for electricity. Using proprietary gas turbine performance simulation software called TURBOMATCH and a computer program written in Microsoft Excel, a redesign of the axial turbine component was achieved. Consequent upon redesigning the axial turbine, a preliminary analysis was carried out to ascertain the new turbine stages introduced. The analysis revealed that when one or two turbine stage(s) was used for new engine, it proved unsatisfactory as the blade loading coefficient and the flow efficiency were both beyond the limit acceptable for an optimum performance. A three stage turbine was finally employed having provided a loading coefficient of 2.1, 1.9 and 1.7 for the first, second and the last stages respectively.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91370646","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}
引用次数: 0
Effect of Water Injection into Aero-derivative Gas Turbine Combustors on NOx Reduction 航空衍生燃气轮机燃烧室注水对NOx还原的影响
European Journal of Engineering Research and Science Pub Date : 2020-11-21 DOI: 10.24018/ejers.2020.5.11.2180
R. Agbadede, B. Kainga
{"title":"Effect of Water Injection into Aero-derivative Gas Turbine Combustors on NOx Reduction","authors":"R. Agbadede, B. Kainga","doi":"10.24018/ejers.2020.5.11.2180","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2180","url":null,"abstract":"Oxides of Nitrogen (NOx) generated from gas turbines causes enormous harm to human health and the environment. As a result, different methods have been employed to reduce NOx produced from gas turbine combustion process. One of such technique is the injection of water or steam into the combustion chamber to reduce the flame temperature. A twin shaft aero-derivative gas turbine was modelled and simulated using GASTURB simulation software. The engine was modelled after the GE LM2500 class of gas turbine engines. Water injection into the gas turbine combustor was simulated by implanting water-to-fuel ratios of 0 to 0.8, in an increasing order of 0.2. The results show that when water-to-fuel ratio was increased, the Nox severity index reduced. While heat rate and fuel flow increased with water-to-fuel ratio (injection flow rate).","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78948081","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}
引用次数: 0
Multi-Modal Natural Frequency Response of Utility Transmission Tapered Wood Poles Under Various Soil Foundation Conditions 不同地基条件下公用传动锥度木杆的多模态固有频率响应
European Journal of Engineering Research and Science Pub Date : 2020-11-19 DOI: 10.24018/ejers.2020.5.11.2054
Ramani Ayakannu, Zia Razzaq
{"title":"Multi-Modal Natural Frequency Response of Utility Transmission Tapered Wood Poles Under Various Soil Foundation Conditions","authors":"Ramani Ayakannu, Zia Razzaq","doi":"10.24018/ejers.2020.5.11.2054","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2054","url":null,"abstract":"Studied herein is the multi-modal natural frequency response of utility transmission tapered wood poles under various soil foundation conditions. Strong winds and hurricanes in various parts of the world have resulted in collapse of such utility poles and have resulted in the disruption of electrical distribution systems in addition to creating hazardous conditions for the public. To avoid the development of resonance under such dynamic loading, the multi-modal natural vibration of the utility poles first needs to be understood in the presence of practical soil foundation conditions. To capture the soil-structure interaction effects on the multi-modal frequencies, a SAP2000 dynamic finite element model is created in which the foundation soil stiffness is characterized by means of a series of ‘soil springs’ below the ground level. The properties of the soil springs vary with types of foundation soils and depths. Three types of foundation soils are considered, namely sandy, clayey soils and Granite (Rock). The results are compared to a standard fixed base model. It is found that the fundamental natural frequencies decreased by 52%, 37%, and 3% for sandy, clayey soils and granite, respectively, when compared to fixed base model. It was observed that there was an increase in the frequencies of the embedded utility poles in clay and granite, when compared to those with the fixed based after the 1st mode whereas, poles embedded in sandy soils showed increase in modal frequencies after the 3rd mode. The 10th mode appears to be a starting point of modal frequency convergence, while an apparent convergence occurs after the 20th mode. The convergent modal frequency was about 740 Hz for the Class H1 utility pole. However, there was a significant increase in the higher modal frequencies such as nearly 55% at the 20th mode, in all soil types when compared to the fixed base model.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77705052","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}
引用次数: 0
Modelling Flow Behavior of Gas Leakage from Buried Pipelineu 埋地管道泄漏气体流动特性模拟
European Journal of Engineering Research and Science Pub Date : 2020-11-16 DOI: 10.24018/ejers.2020.5.11.2117
P. Ndalila, Yuxing Li, Cuiwei Liu
{"title":"Modelling Flow Behavior of Gas Leakage from Buried Pipelineu","authors":"P. Ndalila, Yuxing Li, Cuiwei Liu","doi":"10.24018/ejers.2020.5.11.2117","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2117","url":null,"abstract":"Risks in gas transportation are usually comprised of losses of the valuable gas, fire, explosion, and destruction to the environment. The safety of this infrastructure especially flammable gas pipelines is of great importance due to potential associated risks when leakage happens. An accurate understanding of the dispersion characteristics of the leaked gas from the underground pipe is of great importance. A gas leaking model from the buried pipeline was established based on computational fluid dynamics (CFD) technique, to simulate the situation. At the incidence of leakage, gas will propagate out and cause changes in flow behavior, which will prompt the detectors. The leakage position influences significantly much on the strength of leak signals to be detected at the ground surface. Under the simulation process, the double leakage pipeline model was involved. The variation of flow parameters inside the pipeline, outside pipeline, and the effect of leakage position were depicted and analyzed.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80056678","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}
引用次数: 1
Dynamic Analysis of Encastre Beams by Modification of the System’s Stiffness Distribution 通过修改系统刚度分布来分析encastra梁的动力
European Journal of Engineering Research and Science Pub Date : 2020-11-14 DOI: 10.24018/ejers.2020.5.11.2220
V. Okonkwo, C. Aginam, C. Nwaiwu
{"title":"Dynamic Analysis of Encastre Beams by Modification of the System’s Stiffness Distribution","authors":"V. Okonkwo, C. Aginam, C. Nwaiwu","doi":"10.24018/ejers.2020.5.11.2220","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2220","url":null,"abstract":"Numerical and energy methods are used to dynamically analyze beams and complex structures. Hamilton’s principle gives exact results but cannot be easily applied in frames and complex structures. Lagrange’s equations can easily be applied in complex structures by lumping the continuous masses at selected nodes. However, this would alter the mass distribution of the system, thus introducing errors in the results of the dynamic analysis. This error can be corrected by making a corresponding modification in the systems’ stiffness matrix. This was achieved by simulating a beam with uniformly distributed mass with the force equilibrium equations. The lumped mass structures were simulated with the equations of motion. The continuous systems were analyzed using the Hamilton’s principle and the vector of nodal forces {P} causing vibration obtained. The nodal forces and displacements were then substituted into the equations of motion to obtain the modified stiffness values as functions of a set of stiffness modification factors. When the stiffness distribution of the system was modified by means of these stiffness modification factors, it was possible to predict accurately the natural fundamental frequencies of the lumped mass encastre beam irrespective of the position or number of lumped masses.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76050470","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}
引用次数: 0
Characterization of Multi-Drug Resistant Gram-Negative Bacteria Present in Fresh Leafy & Salad Vegetables in Dhaka, Bangladesh 孟加拉国达卡新鲜叶菜和沙拉蔬菜中多重耐药革兰氏阴性菌的鉴定
European Journal of Engineering Research and Science Pub Date : 2020-11-13 DOI: 10.24018/ejers.2020.5.11.2212
Shahrin Akter Aurin, Sohana Parvin Chowdhury, M. Abony, J. Rifá, A. Banik, A. Fatema, Oshin Ghurnee, Z. Ahmed
{"title":"Characterization of Multi-Drug Resistant Gram-Negative Bacteria Present in Fresh Leafy & Salad Vegetables in Dhaka, Bangladesh","authors":"Shahrin Akter Aurin, Sohana Parvin Chowdhury, M. Abony, J. Rifá, A. Banik, A. Fatema, Oshin Ghurnee, Z. Ahmed","doi":"10.24018/ejers.2020.5.11.2212","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2212","url":null,"abstract":"This study was conducted to determine the microbiological quality of fresh raw and unwashed leafy and salad vegetables in Dhaka, Bangladesh. Six different types of samples (red amaranth, spinach, carrot, radish, tomato, and cucumber) were collected in pre-sterilized zip-lock bags from various local markets in Dhaka. All samples were transported to the Centre of Excellence for Global Health Research Laboratory of Primeasia University at earliest convenience. Samples were enriched in Nutrient Broth media and were then cultured on selective media for isolation purpose. Serial dilution was performed for the total viable count. Biochemical and carbohydrate profiling was conducted for the presumptive identification of the isolates. Commercial antibiotic discs were used for antibiogram by Kirby-Bauer disc diffusion method on Mueller-Hinton agar medium. The total microbial load ranged from 8x107 to 1.70x108. Total 36 isolates were identified, having 7 differentorganisms. The most predominant organism was Vibrio sp. (23%) followed by Klebsiella sp.(20%), Acinetobacter sp. (19%), Pseudomonas sp. (19%), Salmonella sp. (8%), Moraxella sp.(8%) and Escherichia coli (3%). 11% of the Vibrio sp. isolates were V. cholerae, found from 4 samples. No presence of V. cholerae was observed in the tomatosamples. E. coli was observed only in Carrot sample. Antibiotics from 7 different groups were tested against the organisms among which Imipenem showed the highest sensitivity (86%). Following Ceftriaxone (100%), Nitrofurantoin (94%), Erythromycin (89%) and Amoxicillin (83%) had the highest resistance against the isolated organisms. Moreover, most of the isolates showed a multi-drug resistance pattern where they were resistant to at least four drugs. Prevalence of pathogenic bacteria in raw unwashed vegetables can cause potential adverse health effects and therefore the consumers need to be conscious about the matter.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81916901","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}
引用次数: 2
Artificial Intelligence Techniques for Information Security in 5G IoT Environments 5G物联网环境下的信息安全人工智能技术
European Journal of Engineering Research and Science Pub Date : 2020-11-13 DOI: 10.24018/ejers.2020.5.11.2210
I. Petrov, T. Janevski
{"title":"Artificial Intelligence Techniques for Information Security in 5G IoT Environments","authors":"I. Petrov, T. Janevski","doi":"10.24018/ejers.2020.5.11.2210","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2210","url":null,"abstract":"The development of the telecommunication networks observed in present and future time is impressive. Today we witness rapid implementation of 5G networks. We can say that this actually is the moment when (artificial intelligence) AI enters at small door but in the beyond 5G world it is expected to have the prime role in smart operation, management and maintenance of non-software defined networking (SDN), network function virtualization (NFV) and especially at SDN and NFV aware networks. Number of standardization body’s and work groups are focused in a way to create a framework that will define the future use of AI and security standards necessary to exist in order to create health environment for the next generation telecommunication infrastructure. In the wireless world AI/Machine learning (ML) has great potential to shake the way we operate and to become foundation of the transformation that leads to the next industrial revolution. Network virtualization gives flexibility and freedom of the telco operators to choose the hardware and network topology they need for AI/ML platforms and big data sets. 5G and IoT create positive environment for AI and ML development and usage. As the network requirements are developed and the number of the users raises, gains are expected to grow with the number of variables and the interactions among them so it becomes impossible to relay on humans to control the network for increased number of variables and this is why AI with ML and automation become beneficial and necessity to run the future networks. AI generally is defined as capacity of mind or ability to acquire and apply knowledge and skills while ML is defined as learning that does not require explicit programming. Combined usage of AI and ML can optimize almost any component of the wireless network, this does not mean that it should be used everywhere mainly because at the end of the day the cost benefit analysis of its usage must be positive. Smart operation, management and infrastructure maintenance (SOMM) networks are defined as: Intelligent, data driven, integrated and agile. Today AI is introduced but in future it will represent the network engine. It is interesting to mention that network security must be upgraded because the network will provide services for massive number of IoT devices that will have variety of functions and requests. AI/ML can improve the security services and to be used in order to elevate them at advanced level. In this text we focus our attention at AI/ML and security scenarios defined for IoT in 5G environment.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83697855","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}
引用次数: 0
Lateral-Torsional Buckling Strength of Two-Span Glass Fiber Reinforced Polymer Beams 双跨玻璃纤维增强聚合物梁的侧向扭转屈曲强度
European Journal of Engineering Research and Science Pub Date : 2020-11-12 DOI: 10.24018/ejers.2020.5.11.2211
Mojtaba B. Sirjani, Zia Razzaq
{"title":"Lateral-Torsional Buckling Strength of Two-Span Glass Fiber Reinforced Polymer Beams","authors":"Mojtaba B. Sirjani, Zia Razzaq","doi":"10.24018/ejers.2020.5.11.2211","DOIUrl":"https://doi.org/10.24018/ejers.2020.5.11.2211","url":null,"abstract":"This paper presents the outcome of a study of two-span glass fiber reinforced polymer (GFRP) I-section beams susceptible to lateral-torsional buckling when subjected to gradually increasing concentrated vertical load(s) in the presence of two different types of lateral bracing schemes. It is found that loading one span results in a smaller buckling load as compared with the cases with loading in both spans regardless of the type of bracing scheme used. Also, the study shows that the addition of midspan braces for the GFRP beams results in up to 5.5 times increase in the buckling load capacity.","PeriodicalId":12029,"journal":{"name":"European Journal of Engineering Research and Science","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80943378","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}
引用次数: 0
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