首页 > 最新文献

World Journal of Engineering and Technology最新文献

英文 中文
Temperature Research of Permanent Magnet Brushless DC Motor for Electric Balanced Vehicle 电动平衡车用永磁无刷直流电机温度研究
Pub Date : 2019-11-13 DOI: 10.4236/wjet.2019.74b001
Baoguo Wang, Jiangui Li, Dong Ai
A power system structure composed of a brushless DC motor and a cycloidal reducer for electric balanced vehicle has been proposed, and the temperature of important components in this structure would be discussed. The loss generated by the cycloid reducer is negligible, it’s only need to analyze the thermal field of motor. Since the temperature change will affect the material properties of the target motor, the electromagnetic and temperature fields, involved in the motor, are selected for coupling calculation to determine whether the final temperature distribution can meet the requirements of vehicle for use.
提出了一种由无刷直流电动机和摆线针轮减速器组成的电动平衡车动力系统结构,并对该结构中重要部件的温度进行了讨论。摆线针轮减速器产生的损耗可以忽略不计,只需要分析电机的热场即可。由于温度变化会影响目标电机的材料性能,因此选择电机所涉及的电磁场和温度场进行耦合计算,以确定最终的温度分布是否能满足车辆的使用要求。
{"title":"Temperature Research of Permanent Magnet Brushless DC Motor for Electric Balanced Vehicle","authors":"Baoguo Wang, Jiangui Li, Dong Ai","doi":"10.4236/wjet.2019.74b001","DOIUrl":"https://doi.org/10.4236/wjet.2019.74b001","url":null,"abstract":"A power system structure composed of a brushless DC motor and a cycloidal reducer for electric balanced vehicle has been proposed, and the temperature of important components in this structure would be discussed. The loss generated by the cycloid reducer is negligible, it’s only need to analyze the thermal field of motor. Since the temperature change will affect the material properties of the target motor, the electromagnetic and temperature fields, involved in the motor, are selected for coupling calculation to determine whether the final temperature distribution can meet the requirements of vehicle for use.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125031230","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
Research of Three-Phase Unbalanced Treatment in Low-Voltage Distribution Network Based on New Commutation Switch 基于新型换相开关的低压配电网三相不平衡处理研究
Pub Date : 2019-11-13 DOI: 10.4236/wjet.2019.74b002
Xuejie Liu, Junji Jia, Jian Wang
Low-voltage distribution systems in our country are mostly used in agricultural loads and household loads. The value and using time of these kinds of loads are uncontrollable, which lead to the three-phase imbalance in low-voltage distribution system, and seriously affect the quality of power supply. A new type of the commutation system and an improved quantum genetic algorithm (IQGA) are proposed in the paper. At last, the rationality and the efficiency of the method are verified by a practical example.
我国低压配电系统主要用于农业负荷和家庭负荷。这类负荷的取值和使用时间是不可控的,导致低压配电系统三相不平衡,严重影响供电质量。提出了一种新型的换相系统和改进的量子遗传算法。最后通过实例验证了该方法的合理性和有效性。
{"title":"Research of Three-Phase Unbalanced Treatment in Low-Voltage Distribution Network Based on New Commutation Switch","authors":"Xuejie Liu, Junji Jia, Jian Wang","doi":"10.4236/wjet.2019.74b002","DOIUrl":"https://doi.org/10.4236/wjet.2019.74b002","url":null,"abstract":"Low-voltage distribution systems in our country are mostly used in agricultural loads and household loads. The value and using time of these kinds of loads are uncontrollable, which lead to the three-phase imbalance in low-voltage distribution system, and seriously affect the quality of power supply. A new type of the commutation system and an improved quantum genetic algorithm (IQGA) are proposed in the paper. At last, the rationality and the efficiency of the method are verified by a practical example.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115201944","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: 5
Application Research of Gravel and Machine-Made Sand along the KKH-2 Project in Pakistan on Asphalt Pavement 巴基斯坦KKH-2工程碎石及机砂在沥青路面上的应用研究
Pub Date : 2019-11-07 DOI: 10.4236/wjet.2019.74045
Jun Hu, Xia Tian, Gang Wang, Zhiqiang Wang
According to the characteristics of stone along the KKH-2 project in Pakistan, the applicability of gravel and machine-made sand for road engineering was studied. Through investigation, the types of stone along the project were relatively simple, and the stone materials used for road construction were mainly limestone, sandstone and pebbles, and the reserves were abundant. The experiment research and analyses comparisons of the parameters and road performance characteristics of natural gravel materials were carried out, and the design parameters and road performance indicators of natural grit in the current code were supplemented and adjusted to make it more suitable for Pakistan to use natural gravel materials for road construction. Thesis combines the project, proposing that mechanism sand and natural sand mixed concrete is not inferior tonatural sand mixed concrete in terms of technical performance, and the overall cost is lower than that of natural sand mixed concrete. The research results are of great significance for saving engineering construction costs, ensuring road performance and prolonging service life.
根据巴基斯坦KKH-2工程沿线石料的特点,研究了碎石和机砂在道路工程中的适用性。经调查,工程沿线石材种类较为单一,筑路所用石材以石灰岩、砂岩、鹅卵石为主,储量丰富。对天然碎石材料的参数和路用性能特性进行了试验研究和分析比较,并对现行规范中天然碎石的设计参数和路用性能指标进行了补充和调整,使其更适合巴基斯坦使用天然碎石材料进行道路建设。论文结合工程,提出机制砂与天然砂混合混凝土在技术性能上不逊于天然砂混合混凝土,且综合造价低于天然砂混合混凝土。研究成果对节约工程建设成本、保证道路使用性能、延长使用寿命具有重要意义。
{"title":"Application Research of Gravel and Machine-Made Sand along the KKH-2 Project in Pakistan on Asphalt Pavement","authors":"Jun Hu, Xia Tian, Gang Wang, Zhiqiang Wang","doi":"10.4236/wjet.2019.74045","DOIUrl":"https://doi.org/10.4236/wjet.2019.74045","url":null,"abstract":"According to the characteristics of stone along the KKH-2 project in Pakistan, the applicability of gravel and machine-made sand for road engineering was studied. Through investigation, the types of stone along the project were relatively simple, and the stone materials used for road construction were mainly limestone, sandstone and pebbles, and the reserves were abundant. The experiment research and analyses comparisons of the parameters and road performance characteristics of natural gravel materials were carried out, and the design parameters and road performance indicators of natural grit in the current code were supplemented and adjusted to make it more suitable for Pakistan to use natural gravel materials for road construction. Thesis combines the project, proposing that mechanism sand and natural sand mixed concrete is not inferior tonatural sand mixed concrete in terms of technical performance, and the overall cost is lower than that of natural sand mixed concrete. The research results are of great significance for saving engineering construction costs, ensuring road performance and prolonging service life.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129227671","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
Composite Consolidation Coefficient Analysis of Soft Soil with Drainage Water 排水条件下软土复合固结系数分析
Pub Date : 2019-09-24 DOI: 10.4236/wjet.2019.74041
Ji-hui Ding, Kaikai You, Zhongmin Feng, Dongxu Sun
The consolidation coefficient is the most basic parameter to calculate the consolidation rate of soil layer, and the horizontal consolidation coefficient controls the radial water flow into the drainage well. Based on the background of the soft soil in Shantou, Guangdong Province, a series of experimental studies on the consolidation characteristics were carried out by using the modified consolidation instrument. And the concept of the composite consolidation coefficient of the drained water body was put forward. The composite consolidation coefficient reflects the consolidation characteristics of soft soil with drainage water, The test results showed that: 1) The consolidation test with drainage plate is basically consistent with the load compression curve, but its consolidation rate is fast, which is reflected by the composite consolidation coefficient. 2) In the consolidation test of water bodies with drainage, the vertical consolidation coefficient and radial consolidation coefficient are calculated by “three-point method”, and then the composite consolidation coefficient is obtained. The composite consolidation coefficient decreases with the increase of drain spacing ratio, effective drainage diameter and drainage height, which is basically consistent with the theoretical formula. 3) The vertical consolidation coefficient and radial consolidation coefficient decrease with the increase of the diameter of the sample, and the difference is obvious when the load is large. The large-size model with a diameter of 100 mm and a height of 100 mm is about 1.35 times of the vertical consolidation coefficient of the conventional consolidation test.
固结系数是计算土层固结速率的最基本参数,水平固结系数控制着向排水井的径向水流。以广东汕头软土为背景,利用改进的固结仪对其固结特性进行了一系列试验研究。提出了排水水体复合固结系数的概念。复合固结系数反映了排水软土的固结特性,试验结果表明:1)排水板固结试验与荷载压缩曲线基本一致,但其固结速率较快,由复合固结系数反映。2)在有排水的水体固结试验中,采用“三点法”计算竖向固结系数和径向固结系数,得到复合固结系数。复合固结系数随排水间距比、有效排水直径和排水高度的增大而减小,与理论公式基本一致。3)竖向固结系数和径向固结系数随试件直径的增大而减小,且在荷载较大时差异明显。直径为100 mm、高度为100 mm的大尺寸模型竖向固结系数约为常规固结试验的1.35倍。
{"title":"Composite Consolidation Coefficient Analysis of Soft Soil with Drainage Water","authors":"Ji-hui Ding, Kaikai You, Zhongmin Feng, Dongxu Sun","doi":"10.4236/wjet.2019.74041","DOIUrl":"https://doi.org/10.4236/wjet.2019.74041","url":null,"abstract":"The consolidation coefficient is the most basic parameter to calculate the \u0000consolidation rate of soil layer, and the horizontal consolidation coefficient controls \u0000the radial water flow into the drainage well. Based on the background of the soft soil in Shantou, \u0000Guangdong Province, a series of experimental studies on the consolidation characteristics \u0000were carried out by using the modified consolidation instrument. And the concept \u0000of the composite consolidation coefficient of the drained water body was put forward. \u0000The composite consolidation coefficient reflects the consolidation characteristics \u0000of soft soil with drainage water, The test results showed that: 1) The consolidation test \u0000with drainage plate is basically consistent with the load compression curve, but \u0000its consolidation rate is fast, which is reflected by the composite consolidation \u0000coefficient. 2) In the consolidation test of water bodies with drainage, the vertical \u0000consolidation coefficient and radial consolidation coefficient are calculated by “three-point method”, and then the composite consolidation coefficient is obtained. The composite \u0000consolidation coefficient decreases with the increase of drain spacing ratio, effective \u0000drainage diameter and drainage height, which is basically consistent with the theoretical \u0000formula. 3) The vertical consolidation coefficient and radial consolidation coefficient \u0000decrease with the increase of the diameter of the sample, and the difference is \u0000obvious when the load is large. The large-size model with a diameter of 100 mm and a height of 100 mm is about 1.35 times \u0000of the vertical consolidation coefficient of the conventional consolidation test.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115199289","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
Development of Path Planning Algorithm Using Probabilistic Roadmap Based on Modified Ant Colony Optimization 基于改进蚁群优化的概率路线图路径规划算法的发展
Pub Date : 2019-09-24 DOI: 10.4236/wjet.2019.74042
Firas A. Raheem, Mohammed I. Abdulkareem
In this paper, a unique combination among probabilistic roadmap, modified ant colony optimization, and third order B-spline curve has been proposed to solve path planning problems in complex and very complex environments. This proposed approach can be divided into three stages. First stage involves constructing a random roadmap depending on the environment complexity using probabilistic roadmap algorithm. Roadmap can be constructed by distributing N nodes randomly in complex and very complex static environments then pairing these nodes together according to some criteria or conditions. The constructed roadmap contains a huge number of possible random paths that may lead to connecting the start and the goal points together. Second stage includes finding path within the pre-constructed roadmap. Modified ant colony optimization has been proposed to find or to search the best path between start and goal points, where in addition to the proposed combination, ACO has been modified to increase its ability to find shorter path. Finally, the third stage uses B-spline curve to smooth and reduce the total length of the found path in the previous stage. The results of the proposed approach ensure the feasible path between start and goal points in complex and very complex environments. Also, the path is guaranteed to be short, smooth, continuous and safe.
本文提出了一种将概率路线图、改进蚁群优化和三阶b样条曲线相结合的独特方法来解决复杂和极复杂环境下的路径规划问题。该方法可分为三个阶段。第一阶段采用概率路线图算法,根据环境复杂度构建随机路线图。路线图可以通过在复杂和非常复杂的静态环境中随机分布N个节点,然后根据一些标准或条件将这些节点配对在一起来构建。构建的路线图包含大量可能的随机路径,这些路径可能将起点和目标点连接在一起。第二阶段包括在预先构建的路线图中寻找路径。提出了一种改进的蚁群优化算法来寻找或搜索起始点和目标点之间的最佳路径,其中除了提出的组合外,还对蚁群算法进行了改进,以提高其寻找更短路径的能力。最后,第三阶段使用b样条曲线对前一阶段找到的路径进行平滑和减少总长度。该方法的结果保证了在复杂和非常复杂的环境中起始点和目标点之间的可行路径。同时保证了路径的短、顺、连续和安全。
{"title":"Development of Path Planning Algorithm Using Probabilistic Roadmap Based on Modified Ant Colony Optimization","authors":"Firas A. Raheem, Mohammed I. Abdulkareem","doi":"10.4236/wjet.2019.74042","DOIUrl":"https://doi.org/10.4236/wjet.2019.74042","url":null,"abstract":"In this paper, a unique combination among probabilistic roadmap, modified ant colony optimization, and third order B-spline curve has been proposed to solve path planning problems in complex and very complex environments. This proposed approach can be divided into three stages. First stage involves constructing a random roadmap depending on the environment complexity using probabilistic roadmap algorithm. Roadmap can be constructed by distributing N nodes randomly in complex and very complex static environments then pairing these nodes together according to some criteria or conditions. The constructed roadmap contains a huge number of possible random paths that may lead to connecting the start and the goal points together. Second stage includes finding path within the pre-constructed roadmap. Modified ant colony optimization has been proposed to find or to search the best path between start and goal points, where in addition to the proposed combination, ACO has been modified to increase its ability to find shorter path. Finally, the third stage uses B-spline curve to smooth and reduce the total length of the found path in the previous stage. The results of the proposed approach ensure the feasible path between start and goal points in complex and very complex environments. Also, the path is guaranteed to be short, smooth, continuous and safe.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121295629","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: 3
Spatio-Temporal Polar-Inclined Space Mission Architecture for a Refined Retrieve of the Earth’s Gravity Field 面向地球重力场精细反演的时空极倾斜空间任务架构
Pub Date : 2019-09-24 DOI: 10.4236/wjet.2019.74047
B. Elsaka
Future satellite gravity missions (FGMs) have been intensively studied during the last recent years for the era beyond the successful previous GRACE and current GRACE Follow-on satellite missions. Previous studies have investigated the gravity field recovery derived from combined two satellite-pairs (referred here as PI-FGM, a single polar satellite-pair like the GRACE mission combined with another inclined satellite-pair) with different orbital heights of few kilometers and different repeat orbital periods. In this contribution, new innovative idea is introduced by designing the inclined satellite-pair of the FGM at the same orbital height of the polar-type with shifted spatio-temporal (ST-FGM) orbital parameters to avoid any possible collision risk between the two satellite-pairs, polar and inclined, of the FGM architecture. The repeat orbits issue will be taken into consideration through the manuscript and will be set as identical as possible for a fair comparison. The findings through a full-scale simulation analysis show that the new design of shifted spatio-temporal polar-inclined (ST-FGM) mission architecture basically outperforms the two satellite-pairs having different orbital heights (i.e. the PI-FGM mission configuration). Regarding the gravity field recovery, the ST-FGM architecture retrieves the geoid heights with standard deviations of about 17.0 mm providing more isotropic error distribution. An overall improvement by a factor of about 80 and 60 is provided by the ST-FGM and PI-FGM mission architectures, respectively, with respect to the GRACE-like formation and a factor of about 2.4 and 1.8, respectively, with respect to the smoothed gravity solution using the Gaussian filter at radius 400 km. Therefore, the shifted spatio-temporal polar-inclined (ST-FGM) is worthy recommended as stable mission architecture and would be considered as one of the future gravity missions.
在过去的几年里,未来的卫星重力任务(fgm)已经被深入研究,以超越之前成功的GRACE和目前的GRACE后续卫星任务。以往的研究已经对不同轨道高度为几公里、不同重复轨道周期的两对卫星组合(这里称为PI-FGM,即像GRACE任务一样的单极卫星对与另一倾斜卫星对的组合)重力场恢复进行了研究。本文提出了一种新颖的设计思路,即采用平移的ST-FGM轨道参数,设计具有相同极型轨道高度的FGM倾斜卫星对,以避免FGM结构中两颗倾斜卫星对之间可能发生的碰撞风险。重复轨道问题将通过手稿加以考虑,并将设置为尽可能相同,以进行公平比较。全尺寸仿真分析结果表明,新设计的位移时空极斜(ST-FGM)任务结构基本优于两对不同轨道高度卫星(即PI-FGM任务结构)。在重力场恢复方面,ST-FGM架构反演的大地水准面高度标准差约为17.0 mm,具有更好的各向同性误差分布。ST-FGM和PI-FGM任务架构在grace -类地层方面分别提供了约80和60倍的总体改进,在半径400公里处使用高斯滤波器的平滑重力解方面分别提供了约2.4和1.8倍的改进。因此,位移时空极倾角(ST-FGM)作为稳定的任务架构值得推荐,并可作为未来的重力任务之一考虑。
{"title":"Spatio-Temporal Polar-Inclined Space Mission Architecture for a Refined Retrieve of the Earth’s Gravity Field","authors":"B. Elsaka","doi":"10.4236/wjet.2019.74047","DOIUrl":"https://doi.org/10.4236/wjet.2019.74047","url":null,"abstract":"Future satellite gravity missions (FGMs) have been intensively studied during the last recent years for the era beyond the successful previous GRACE and current GRACE Follow-on satellite missions. Previous studies have investigated the gravity field recovery derived from combined two satellite-pairs (referred here as PI-FGM, a single polar satellite-pair like the GRACE mission combined with another inclined satellite-pair) with different orbital heights of few kilometers and different repeat orbital periods. In this contribution, new innovative idea is introduced by designing the inclined satellite-pair of the FGM at the same orbital height of the polar-type with shifted spatio-temporal (ST-FGM) orbital parameters to avoid any possible collision risk between the two satellite-pairs, polar and inclined, of the FGM architecture. The repeat orbits issue will be taken into consideration through the manuscript and will be set as identical as possible for a fair comparison. The findings through a full-scale simulation analysis show that the new design of shifted spatio-temporal polar-inclined (ST-FGM) mission architecture basically outperforms the two satellite-pairs having different orbital heights (i.e. the PI-FGM mission configuration). Regarding the gravity field recovery, the ST-FGM architecture retrieves the geoid heights with standard deviations of about 17.0 mm providing more isotropic error distribution. An overall improvement by a factor of about 80 and 60 is provided by the ST-FGM and PI-FGM mission architectures, respectively, with respect to the GRACE-like formation and a factor of about 2.4 and 1.8, respectively, with respect to the smoothed gravity solution using the Gaussian filter at radius 400 km. Therefore, the shifted spatio-temporal polar-inclined (ST-FGM) is worthy recommended as stable mission architecture and would be considered as one of the future gravity missions.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121218728","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
Damage Evaluation of Two Equatorial Hardwoods under Uniaxial Compression: Case of Entandrophragma cylindricum (Sapelli) and Chlorophora exelcia (Iroko) 两种赤道阔叶树在单轴压缩下的损伤评价——以白蜡内参和绿萝为例
Pub Date : 2019-09-24 DOI: 10.4236/wjet.2019.74039
Thierry Fothe, Ulrich Gael Azeufack, B. Kenmeugne, P. K. Talla, M. Fogué
This work aims at characterizing the evolution of the damage of two tropical hardwoods. Two species from Cameroon, the Entandrophragma Cylindricum and the Chlorora Exelcia were used for the purpose. Repeated compressive loading has been made on specimens strictly selected along with longitudinal and radial directions of each species. Each cycle was made of one phase of monotonic loading and a phase of elastic release. From data obtained, we determined the variation of Young modulus and plastic deformation during each cycle of loading, and we had deduced the damage of the material. Results show that the damage appears only after a certain threshold of the plastic deformation; that damage then grows exponentially to reach a threshold after which the failure of the material occurs. As well, we noticed that the growth of damage is accompanied by the progressive decrease of the Young modulus; this confirms the deteriorating effect of the damage on the mechanical properties. Elsewhere, the damage failure threshold is less than the theoretical value, and differs from one direction to another. Finally, we noticed that the damage failure threshold of sapelli is greater than that of iroko that allows concluding that iroko gets damaged and fails more rapidly than sapelli.
这项工作的目的是描述两种热带硬木的损害演变。本研究选用喀麦隆的两个种,即白茅(Entandrophragma um)和白茅(Chlorora Exelcia)。严格按照各试件纵向和径向方向进行反复压缩加载。每个循环由一个单调加载阶段和一个弹性释放阶段组成。根据得到的数据,确定了各循环加载过程中杨氏模量和塑性变形的变化情况,并推导出了材料的损伤情况。结果表明:塑性变形达到一定阈值后才会出现损伤;然后,这种破坏呈指数增长,达到一个阈值,超过这个阈值,材料就会失效。同时,损伤的增长伴随着杨氏模量的逐渐减小;这证实了损伤对机械性能的恶化影响。其他地方的损伤破坏阈值均小于理论值,且各方向不同。最后,我们注意到sapelli的损伤失效阈值大于iroko,这可以得出结论,iroko比sapelli更快地受到损伤和失效。
{"title":"Damage Evaluation of Two Equatorial Hardwoods under Uniaxial Compression: Case of Entandrophragma cylindricum (Sapelli) and Chlorophora exelcia (Iroko)","authors":"Thierry Fothe, Ulrich Gael Azeufack, B. Kenmeugne, P. K. Talla, M. Fogué","doi":"10.4236/wjet.2019.74039","DOIUrl":"https://doi.org/10.4236/wjet.2019.74039","url":null,"abstract":"This work aims at characterizing the evolution of the damage of two tropical hardwoods. Two species from Cameroon, the Entandrophragma Cylindricum and the Chlorora Exelcia were used for the purpose. Repeated compressive loading has been made on specimens strictly selected along with longitudinal and radial directions of each species. Each cycle was made of one phase of monotonic loading and a phase of elastic release. From data obtained, we determined the variation of Young modulus and plastic deformation during each cycle of loading, and we had deduced the damage of the material. Results show that the damage appears only after a certain threshold of the plastic deformation; that damage then grows exponentially to reach a threshold after which the failure of the material occurs. As well, we noticed that the growth of damage is accompanied by the progressive decrease of the Young modulus; this confirms the deteriorating effect of the damage on the mechanical properties. Elsewhere, the damage failure threshold is less than the theoretical value, and differs from one direction to another. Finally, we noticed that the damage failure threshold of sapelli is greater than that of iroko that allows concluding that iroko gets damaged and fails more rapidly than sapelli.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115294424","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
Development of Drone Cargo Bay with Real-Time Temperature Control 实时温度控制无人机货舱的研制
Pub Date : 2019-09-24 DOI: 10.4236/wjet.2019.74044
Sedam Lee, Yongjin Kwon
In order to deliver medical products (medicines, vaccines, blood packs, etc.) in time for needed areas, a method of transporting goods using drones is being studied. However, temperature-sensitive medical products may decay due to outside temperature changes. The time required to transport over the distance may vary a lot as well. As a result, the likelihood of the goods deteriorating is very high. There is a need for a study on cargo bay to prevent this and to protect the medical goods. In this paper, in order to protect the temperature sensitive medical goods, the inside cargo bay is equipped with the cooling fan device and the electric heating elements. These elements can be monitored and controlled according to the user’s discretion. By using the web server built inside the cloud server, the temperature can be controlled in real-time from anywhere without the limitation of distance. We built the proposed device, and installed it on the drone cargo bay. The test results show that the cargo bay can be temperature-controlled, and the setting can be maintained over a great distance. The user can watch the temperature variations during the transport and ascertain the goodness of the medical supply with the data. It is expected that such development can greatly enhance the utility of the drone operations, especially for the medical supply transport applications.
为了及时向需要的地区运送医疗产品(药品、疫苗、血包等),正在研究使用无人机运输货物的方法。然而,对温度敏感的医疗产品可能会因外界温度的变化而腐烂。长途运输所需的时间也可能相差很大。因此,货物变质的可能性非常高。有必要对货舱进行研究,以防止这种情况的发生,保护医疗物资。在本文中,为了保护对温度敏感的医疗物品,在内货舱设置了冷却风扇装置和电热元件。这些元素可以根据用户的判断进行监视和控制。通过使用内置在云服务器内的web服务器,可以在任何地方不受距离限制地实时控制温度。我们制作了这个装置,并把它安装在无人机的货舱上。试验结果表明,货舱可实现温度控制,且设置可远距离保持。用户可以观察运输过程中的温度变化,并根据数据确定医疗用品的质量。预计这种发展可以大大提高无人机作业的效用,特别是在医疗用品运输应用方面。
{"title":"Development of Drone Cargo Bay with Real-Time Temperature Control","authors":"Sedam Lee, Yongjin Kwon","doi":"10.4236/wjet.2019.74044","DOIUrl":"https://doi.org/10.4236/wjet.2019.74044","url":null,"abstract":"In order to deliver medical products (medicines, vaccines, blood packs, etc.) in time for needed areas, a method of transporting goods using drones is being studied. However, temperature-sensitive medical products may decay due to outside temperature changes. The time required to transport over the distance may vary a lot as well. As a result, the likelihood of the goods deteriorating is very high. There is a need for a study on cargo bay to prevent this and to protect the medical goods. In this paper, in order to protect the temperature sensitive medical goods, the inside cargo bay is equipped with the cooling fan device and the electric heating elements. These elements can be monitored and controlled according to the user’s discretion. By using the web server built inside the cloud server, the temperature can be controlled in real-time from anywhere without the limitation of distance. We built the proposed device, and installed it on the drone cargo bay. The test results show that the cargo bay can be temperature-controlled, and the setting can be maintained over a great distance. The user can watch the temperature variations during the transport and ascertain the goodness of the medical supply with the data. It is expected that such development can greatly enhance the utility of the drone operations, especially for the medical supply transport applications.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116123625","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
The Analysis of Thermomechanical Periodic Motions of a Drinking Bird 饮水鸟的热力周期运动分析
Pub Date : 2019-09-24 DOI: 10.4236/wjet.2019.74040
Schun T. Uechi, H. Uechi, A. Nishimura
A water drinking bird or simply drinking bird (DB) is discussed in terms of a thermomechanical model. A mathematical expression of motion derived from the thermomechanical model of a drinking bird and numerical solutions are explicitly shown, which is helpful in understanding physical meanings and fundamental difference between mechanical and thermomechanical periodic motion. The mathematical and physical differences between mechanical and thermomechanical motions are clearly examined, resulting in time-independent and time-dependent coupling constants of equations of motion and continuous transitions between bifurcation solutions. The thermodynamical and irreversible process of a drinking bird motion could be theoretically examined and practically applied to energy harvesting technologies by way of the current modeling. As an example of irreversible thermodynamics, the thermomechanical model of DB will help understand heat engines manifested from microscopic to macroscopic systems.
用热力学模型讨论了饮水鸟或简单饮水鸟。本文给出了饮水鸟热力学模型的运动数学表达式和数值解,有助于理解机械周期运动和热力学周期运动的物理意义和基本区别。机械运动和热机械运动之间的数学和物理差异被清楚地检查,导致运动方程的时间无关和时间相关的耦合常数和分岔解之间的连续转换。通过现有的模型,可以从理论上考察饮水鸟运动的热力学和不可逆过程,并将其实际应用于能量收集技术。作为不可逆热力学的一个例子,DB的热力模型将有助于理解从微观到宏观系统表现出来的热机。
{"title":"The Analysis of Thermomechanical Periodic Motions of a Drinking Bird","authors":"Schun T. Uechi, H. Uechi, A. Nishimura","doi":"10.4236/wjet.2019.74040","DOIUrl":"https://doi.org/10.4236/wjet.2019.74040","url":null,"abstract":"A water drinking bird or simply drinking bird (DB) is discussed in terms of a thermomechanical model. A mathematical expression of motion derived from the thermomechanical model of a drinking bird and numerical solutions are explicitly shown, which is helpful in understanding physical meanings and fundamental difference between mechanical and thermomechanical periodic motion. The mathematical and physical differences between mechanical and thermomechanical motions are clearly examined, resulting in time-independent and time-dependent coupling constants of equations of motion and continuous transitions between bifurcation solutions. The thermodynamical and irreversible process of a drinking bird motion could be theoretically examined and practically applied to energy harvesting technologies by way of the current modeling. As an example of irreversible thermodynamics, the thermomechanical model of DB will help understand heat engines manifested from microscopic to macroscopic systems.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116346328","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: 5
An Introduction to Architecture of Nasir Al-Mulk Mosque Nasir Al-Mulk清真寺建筑简介
Pub Date : 2019-09-24 DOI: 10.4236/wjet.2019.74048
A. Ehteshami, M. Soltaninejad
In analazying the form in architectural monuments or in a more comprehensive way, study of the monuments itself is one of the most fundamental and most important aspects of architecture that has several benefits and effects. One of the benefits of recognizing the shape of different building architecture is the categorization of architecture into different historical periods that can help us better understand the process of historical architectural developments in the past. Among the architectural monuments of Iran, Nasir al-Mulk Mosque in Shiraz which is a Qajar Mosque is one of the most important Mosques in Shiraz which is less focused in the previous studies. This article, which is mainly based on empirical research and field studies, was conducted for studying the architecture of the mosque and analyzing and explaining the most important architectural features of this monument. The main questions of this article are the following: 1) What are the most basic architectural features of Nasir al-Mulk Mosque and how different parts are organized and built next to each other? 2) What choices and opting out of the architectural design of the building have been carried out? To find the best answers to these questions, first we analyzed the structure and overall fitness of the Mosque and its characteristics had been enumerated. Then, we introduced and analyze the main sectors that make up the corpus such as the mosque entrance, courtyard, naves and porches, in which the form and structure of each of these sectors as well as their consort with each other in shaping the overall architecture of the mosque, are analyzed and discussed. The summary of the findings in the form of empirical statements is presented at the end of the article.
在分析或更全面地分析建筑纪念物的形式时,对纪念物本身的研究是建筑学最基本、最重要的方面之一,它有几个好处和作用。认识不同建筑形式的好处之一是将建筑划分为不同的历史时期,这可以帮助我们更好地了解过去历史建筑发展的过程。在伊朗的建筑古迹中,设拉子的Nasir al-Mulk清真寺是一座卡扎尔清真寺,是设拉子最重要的清真寺之一,在以往的研究中较少受到关注。本文主要采用实证研究和实地调研相结合的方法,对该清真寺的建筑进行研究,分析和解释该纪念碑最重要的建筑特征。本文的主要问题是:1)Nasir al-Mulk清真寺最基本的建筑特征是什么,不同的部分是如何组织和相邻建造的?2)对建筑的建筑设计进行了哪些选择和退出?为了找到这些问题的最佳答案,我们首先分析了清真寺的结构和整体适应性,并列举了其特征。然后,我们介绍和分析了构成主体的主要部分,如清真寺入口、庭院、中殿和门廊,其中分析和讨论了每个部分的形式和结构,以及它们在塑造清真寺整体建筑中的相互配合。以实证陈述的形式总结了研究结果,并在文章的末尾提出。
{"title":"An Introduction to Architecture of Nasir Al-Mulk Mosque","authors":"A. Ehteshami, M. Soltaninejad","doi":"10.4236/wjet.2019.74048","DOIUrl":"https://doi.org/10.4236/wjet.2019.74048","url":null,"abstract":"In analazying \u0000the form in \u0000architectural monuments or in a more comprehensive way, study of the monuments itself is one of the most fundamental and \u0000most important aspects of architecture that has several benefits and effects. One \u0000of the benefits of recognizing the shape of different building architecture is \u0000the categorization of architecture into different historical periods that can help us better understand the process of historical architectural \u0000developments in the past. Among the architectural monuments of Iran, Nasir \u0000al-Mulk Mosque in Shiraz which is a Qajar Mosque is one of the most important \u0000Mosques in Shiraz which is less focused in the previous studies. This article, \u0000which is mainly based on empirical research and field studies, was conducted \u0000for studying the architecture of the mosque and analyzing and explaining the most important architectural features of this monument. The main \u0000questions of this article are the following: 1) What are the most basic \u0000architectural features of Nasir al-Mulk \u0000Mosque and how different parts are organized and built next to each other? 2) What \u0000choices and opting out of the architectural design of the building have been carried out? To find the best answers to \u0000these questions, first we analyzed the structure and overall fitness of the Mosque \u0000and its characteristics had been enumerated. Then, we introduced and analyze the main sectors that make up the corpus such as \u0000the mosque entrance, courtyard, naves and porches, in which the form and structure of each of these \u0000sectors as well as their consort with each other \u0000in shaping the overall architecture of the mosque, are analyzed and discussed. The summary of the findings in the form of \u0000empirical statements is presented at the end of the article.","PeriodicalId":344331,"journal":{"name":"World Journal of Engineering and Technology","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116072812","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: 5
期刊
World Journal of Engineering and Technology
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1