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Logistics Management in the Ghanaian Construction Industry 加纳建筑业的物流管理
Pub Date : 2021-07-15 DOI: 10.4236/wjet.2021.93029
Boateng Leslie Appiah
In the field of the construction industry, logistics management has become an issue of concern which needs to be focused on in order to ensure effective, successful and timely execution of projects in the construction industry. Logistics management in construction is a multidisciplinary process which makes sure things are done at the right time, cost and quality as well as material supply and handling, schedule control, site infrastructure and equipment location, site physical flow management, traffic arrangements on and around the construction site, and information management related to all physical and services flow. This paper seeks to identify and evaluate the possible factors that affect logistics management in the construction industry and also to ascertain the current practices of inventory management and the effect on logistics management envisage by construction personnel’s and stake holders. A descriptive survey research was conducted with both structured and unstructured questionnaire and administered both via e-mail and by sending questionnaire link onto a WhatsApp platform groups of the respondents, and out of the 187 respondents that took part in the survey, 22 respondents feedback were incomplete so 165 member respondents results were analyzed representing 88.2% response rate. The survey results were analyzed, displayed and interpreted in the form of tables, bar charts, column chart and pie chart with the use of SPSS software. The research survey respondents were comprised of Project Managers, Project Coordinators, Foremen, Site Managers/ Officers, Logistics Managers, Inventory Managers and Laborers. The survey results revealed that majority of the total respondents are in the capacity or position as Logistics Managers and also have from 5 to 10 years working experience, and as well majority of the respondents have also attained Master’s degree qualification. It was also revealed that logistics management is greatly affected by the inability or the failure to embrace, adopt and integrate new and emerging technology and its approach into the logistics management system. Majority of the respondents also indicated that in general the adequacy of inventory management system was dissatisfied representing 63.8% of the total respondents. The construction industry not only needed to improve its inventory management systems but also to ensure appropriate inventory management techniques for enhancing high degree of accuracy, reduced cycle times and replenishment of stock. This usually accounts for the poor delivery and quality of work, accompanied with delays and other associated losses in project construction. For effective Logistics management to be achieved in the construction industry, the introduction of modern technology to carry out logistics functions in the construction industry should be paramount to the industry players.
在建筑行业领域,为了保证建筑行业项目的有效、成功和及时的执行,物流管理已经成为一个需要关注和关注的问题。施工中的物流管理是一个多学科的过程,它确保在正确的时间、成本和质量、材料供应和处理、进度控制、现场基础设施和设备位置、现场物理流程管理、施工现场及其周围的交通安排以及与所有物理和服务流程相关的信息管理。本文旨在识别和评估影响建筑行业物流管理的可能因素,并确定当前库存管理的做法以及建筑人员和利益相关者对物流管理的影响。通过结构化和非结构化问卷进行描述性调查研究,并通过电子邮件和将问卷链接发送到受访者的WhatsApp平台组进行管理,在187名受访者中,有22名受访者的反馈不完整,因此分析了165名成员受访者的结果,占88.2%的回复率。运用SPSS软件,以表格、条形图、柱状图、饼状图等形式对调查结果进行分析、显示和解释。调查对象包括项目经理、项目协调员、工头、现场经理/官员、物流经理、库存经理和工人。调查结果显示,大多数受访者的能力或职位是物流经理,也有5到10年的工作经验,而且大多数受访者也获得了硕士学位资格。报告还显示,物流管理受到无法或未能接受、采用和整合新兴技术及其方法到物流管理系统中的很大影响。大多数受访者亦表示,整体而言,对存货管理系统的充分性不满意,占总受访者的63.8%。建筑业不仅需要改进其库存管理系统,而且还需要确保适当的库存管理技术,以提高高度的准确性,缩短周期时间和补充库存。这通常导致工作的交付和质量差,并伴随着项目建设中的延误和其他相关损失。为了在建造业中实现有效的物流管理,引入现代技术来执行建造业的物流功能对行业参与者来说是至关重要的。
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引用次数: 0
Comparative Analysis of Hybrid Controllers of Done Systems (UPFC) and Interphase Power Regulators Type RPI 30p15 on Contingency Management in Electrical Networks 完成系统混合控制器(UPFC)与RPI 30p15型间相功率调节器在电网应急管理中的比较分析
Pub Date : 2021-07-15 DOI: 10.4236/wjet.2021.93048
Koko Koko Joseph, N. N. Léandre, N. Salomé, Batassou Guilzia Jeannot
The aim of this work is to demonstrate that interphase power regulators (IPR) bring new and interesting ultra-solutions that complement those already taken into account by the FACTS (Flexible Alternative Transmission System) in the resolution of the problems related to the power flow in the AC transmission networks. In order to facilitate the understanding of this work, a comparative study of the performances of the two technologies between the UPFC (Unified Power Flow Controller) and RPI was carried out and at the end of which we were able to highlight the preponderance of RPI compared to the UPFC in the bypassing of the short-circuit fault insofar as the latter allows, in particular, an increase in the transformation capacity without an increase in the level of the short-circuit. The decoupled watt-var method has been used to control the UPFC while the RPI is controlled by phase shift. The simulation results are obtained in the Matlab Simulink environment and show the flexibility of the RPI compared to the UPFC in limiting strong contingencies.
这项工作的目的是证明间相功率调节器(IPR)带来了新的和有趣的超解决方案,补充了在解决交流输电网络中与潮流相关的问题时已经考虑到的FACTS(灵活替代传输系统)。为了促进这项工作的理解,表现的比较研究这两种技术之间的UPFC(统一潮流控制器)和零售物价指数进行了最后的我们能够突出零售物价指数的优势相比,UPFC的绕过短路故障只要后者允许,特别是增加转换能力没有短路的水平的增加。采用解耦的瓦无法控制UPFC,采用相移控制RPI。仿真结果在Matlab Simulink环境下得到,显示了RPI与UPFC相比在限制强偶然性方面的灵活性。
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引用次数: 1
The Effect of Stem Diameter on the Brassica napus (Type: Canola) (Cultivar: HYHEAR 3) Fiber Quality 茎粗对甘蓝型油菜(品种:HYHEAR 3)纤维品质的影响
Pub Date : 2021-04-27 DOI: 10.4236/wjet.2021.93031
A. Parvin, Mashiur Rahman, D. Cattani
A matured canola plant has different types of stems based on the diameter, such as narrow (immature), medium (mature), and wide (over mature). Therefore, this study was focused on investigating the properties of the extracted canola (HYREAR 3) fibers from 3 different diameter of stems (narrow, medium and wide). The physical (average length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of fibers were measured. ANOVA showed that stem diameter had effects on all fiber properties except for average length and elongation at break. Fiber diameter also had significant effects on load at break, elongation at break, aspect ratio, tensile stress, and young’s modulus. In corrgram, it was found that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were positively associated. Mean values showed that stem diameter had effects on all fiber properties except for average length. The mean values of fiber diameter, load at break, elongation at break, tenacity, and contact angle were highest and the lowest mean values were observed for tensile stress, young’s modulus and aspect ratio in fibers of 7 - 10 mm stems (medium matured), hence found to be less stiff. Moisture regain ability showed that canola fibers isolated from ≥8 mm stem diameter were more hydrophobic whereas contact angle measurement showed relatively more hydrophobic nature of 7 - 10 mm stem fibers. Therefore, this study provided an insightful understanding of the quality of the canola fibers of different stems which will ultimately help to choose the best stem to extract different qualities of fibers for commercial uses.
成熟的油菜籽植物根据直径有不同类型的茎,如窄(未成熟),中(成熟)和宽(过成熟)。因此,本研究重点研究了从3种不同茎径(窄、中、宽)中提取的油菜籽(HYREAR 3)纤维的性能。测量了纤维的物理性能(平均长度、纵横比、接触角和回潮率)和机械性能(断裂载荷、断裂伸长率、拉伸应力、杨氏模量和韧性)。方差分析表明,茎直径对除平均长度和断裂伸长率外的所有纤维性能都有影响。纤维直径对断裂载荷、断裂伸长率、长径比、拉伸应力和杨氏模量也有显著影响。在相关图中,拉伸应力、杨氏模量和长径比与纤维直径呈负相关,而断裂载荷和韧性呈正相关。平均值表明,茎直径对除平均长度外的所有纤维性能都有影响。纤维直径、断裂载荷、断裂伸长率、韧性和接触角的平均值最高,拉伸应力、杨氏模量和长径比的平均值最低,因此发现7 - 10 mm茎(中等成熟)的纤维硬度较低。吸湿能力表明,≥8mm茎粗分离的油菜籽纤维疏水性较好,而接触角测定结果表明,7 ~ 10mm茎粗分离的油菜籽纤维疏水性较好。因此,本研究提供了对不同茎段油菜籽纤维品质的深入了解,最终有助于选择最佳茎段提取不同品质的油菜籽纤维用于商业用途。
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引用次数: 0
Trend Analysis of Large-Scale Twitter Data Based on Witnesses during a Hazardous Event: A Case Study on California Wildfire Evacuation 危险事件中基于目击者的大规模Twitter数据趋势分析——以加州野火疏散为例
Pub Date : 2021-04-06 DOI: 10.4236/WJET.2021.92016
S. Morshed, Khandakar Mamun Ahmed, Kamar Amine, K. A. Moinuddin
Social media data created a paradigm shift in assessing situational awareness during a natural disaster or emergencies such as wildfire, hurricane, tropical storm etc. Twitter as an emerging data source is an effective and innovative digital platform to observe trend from social media users’ perspective who are direct or indirect witnesses of the calamitous event. This paper aims to collect and analyze twitter data related to the recent wildfire in California to perform a trend analysis by classifying firsthand and credible information from Twitter users. This work investigates tweets on the recent wildfire in California and classifies them based on witnesses into two types: 1) direct witnesses and 2) indirect witnesses. The collected and analyzed information can be useful for law enforcement agencies and humanitarian organizations for communication and verification of the situational awareness during wildfire hazards. Trend analysis is an aggregated approach that includes sentimental analysis and topic modeling performed through domain-expert manual annotation and machine learning. Trend analysis ultimately builds a fine-grained analysis to assess evacuation routes and provide valuable information to the firsthand emergency responders.
社交媒体数据在评估自然灾害或紧急情况(如野火、飓风、热带风暴等)期间的态势感知方面创造了一种范式转变。Twitter作为一种新兴的数据来源,是一个有效的创新的数字平台,可以从作为灾难事件直接或间接目击者的社交媒体用户的角度来观察趋势。本文旨在通过对twitter用户提供的第一手可信信息进行分类,收集和分析与近期加州野火相关的twitter数据,进行趋势分析。这项工作调查了最近加州野火的推文,并根据证人将其分为两类:1)直接证人和2)间接证人。收集和分析的信息可用于执法机构和人道主义组织在野火灾害期间的沟通和核实态势感知。趋势分析是一种聚合方法,包括情感分析和通过领域专家手动注释和机器学习执行的主题建模。趋势分析最终构建了细粒度分析,以评估疏散路线,并为第一手应急响应人员提供有价值的信息。
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引用次数: 2
Evaluating Contractors’ Safety Record and Its Influence on Performance of Road Infrastructural Projects 公路基础设施工程承包商安全记录评价及其对工程绩效的影响
Pub Date : 2021-03-31 DOI: 10.4236/WJET.2021.92015
James Mushori, C. Rambo, C. Wafula, Johnson Matu
A number of studies conducted in Kenya and internationally indicated that most of the construction firms and contractors do not seem to strictly observe safety administration in construction industry, hence compromised performance at implementation stage of projects and even later in the post implementation or post-delivery stage. The study aimed to examine the influence of contractors’ safety record on road performance. This is to create better understanding of how the safety record of contractors could either positively or negatively influence performance of roads during post-delivery stage. The study used both descriptive survey research design and correlation design based on a pragmatic mixed method approach. Through stratified sampling and proportionate sampling, a sample of 210 was drawn from a population of 460 comprising of registered contractors and Public Service Vehicles (PSV) drivers within Nairobi County in Kenya. Questionnaires were distributed using simple random sampling. The questionnaires returned were 153 in total representing 72.8% of all questionnaires distributed to the respondents. Data was descriptively analyzed using percentages, frequencies, means and standard deviations for measuring central tendency and variability. Inferential analysis was done by use of correlation and regression. The descriptive analysis revealed that safety policy management system, insurance policy, and adequacy of standards in addressing safety outcome are to some extent practiced and adhered to. However, compliance behavior to safety procedures is still weak and requires improvement. The null hypothesis was tested and the results obtained from a simple linear regression indicated that, R = 0.657, R2 = 0.431, B = 0.359, t = 10.703, F (1,151) = 114.558, p = 0.000 < 0.05. This means that contractors’ safety record has a strong positive and significant relationship with road performance and that 43.1% of variation in performance is explained by safety record. This study recommends that contractors’ safety record should be part, and parcel of the evaluation criteria used in selection of a suitable road contractor to ensure road performance is achieved even after construction is completed. The study is significant in that it contributes to the body of knowledge by providing empirical data on the need for safety procedures in urban road construction and beyond.
在肯尼亚和国际上进行的一些研究表明,大多数建筑公司和承包商似乎没有严格遵守建筑业的安全管理,因此在项目的执行阶段,甚至在执行后或交付后阶段的业绩受到损害。本研究旨在检验承包商的安全记录对道路性能的影响。这是为了更好地了解承包商的安全记录如何在交付后阶段对道路的性能产生积极或消极的影响。本研究采用描述性调查研究设计和基于语用混合方法的相关设计。通过分层抽样和比例抽样,从肯尼亚内罗毕县460名登记承包商和公共服务车辆司机中抽取了210名样本。问卷采用简单随机抽样的方式发放。回收的问卷共153份,占已派发问卷总数的72.8%。使用百分比、频率、平均值和标准偏差对数据进行描述性分析,以测量集中趋势和变异性。采用相关性和回归分析方法进行推理分析。描述性分析表明,安全政策、管理体系、保险政策和处理安全结果的标准的充分性在一定程度上得到了实践和遵守。然而,对安全程序的遵守行为仍然薄弱,需要改进。对原假设进行检验,简单线性回归结果显示,R = 0.657, R2 = 0.431, B = 0.359, t = 10.703, F (1,151) = 114.558, p = 0.000 < 0.05。这意味着承包商的安全记录与道路性能有很强的正相关关系,并且43.1%的性能变化可以用安全记录来解释。本研究建议,在选择合适的道路承包商时,承包商的安全记录应作为评估标准的一部分,以确保即使在施工完成后也能达到道路性能。该研究的重要之处在于,它通过提供有关城市道路建设及其他领域安全程序需求的经验数据,为知识体系做出了贡献。
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引用次数: 1
Novel Cascade Refrigeration Cycle for Cold Supply Chain of COVID-19 Vaccines at Ultra-Low Temperature -80°C Using Ethane (R170) Based Hydrocarbon Pair 基于乙烷(R170)碳氢化合物对的新型冠状病毒疫苗超低温-80℃冷供应链级联制冷循环
Pub Date : 2021-03-30 DOI: 10.4236/WJET.2021.92022
T. A. Mouneer, Abdelrahman M. Elshaer, M. H. Aly
Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80°C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per Montreal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard.
多家媒体报道强调,制药公司需要-80°C的超低温来运输和储存新冠病毒疫苗。本文对R32/R170、R123/R170、R134a/R170、R404A/R170、R407c/R170、R410/R170以及烃类制冷剂(HC)丙烷/乙烷对R290/R170的复叠制冷系统(CRS)进行了热力学分析。此外,根据《蒙特利尔议定书》,R22/R170对已不再被推荐使用,本文将R22/R170对的结果作为基准案例,比较CRS中新型碳氢化合物对和制冷剂对的旧趋势。在低温循环(LTC)和高温循环(HTC)热连接的CRS换热器中,研究并比较了不同中间温度下这三种材料的热力学性质。应用热力学第一定律,给出并比较了性能系数(cop)和比功耗(SPC) (kW/TR)。此外,利用热力学第二定律估计了其火用效率。结果表明,使用HC对(R290/R170)是有希望的。记录R123/R170对的最小SPC (kW/TR)。另一方面,R123/R170、R290/R170和R134/R170的高能化效率分别为40%、38%和35%。本研究得出结论,HC对(R290/R170)强烈推荐用于CRS应用,无论是运输COVID-19还是在医院和诊所的冷库中储存。由于HC对(R290/R170)的可燃性,在设计和操作中应仔细采取所有预防措施。
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引用次数: 12
Generation of Ultrasound Based on the Frequency Response Characteristics of the “Koss Pro Headphone” with R. David Case Sound Wave Files’—A Case Study 基于“Koss Pro耳机”频率响应特性的超声产生与R. David Case声波文件的案例研究
Pub Date : 2021-03-30 DOI: 10.4236/WJET.2021.92026
R. D. Case, D. Chuckravanen
The research aim of this work is to analyse the characteristics of R. David Case Sound waves that are posited to have positive effects on people suffering from tinnitus. Moreover, the participants who listened to these sound wave files using specific headsets or headphones of the Koss models (ktx Pro, ksc-75) showed improved health condition such as alleviating tinnitus that they are suffering from. Therefore, these discoveries have encouraged R. David Case to pursue positively his journey into finding out what is special about those sounds when being listened specifically with Koss models. In this research, we focus mainly on the technical aspects of R. David Case sound signals which he has recorded. These specific sound waves were analysed using time domain, frequency domain as well as the effect of using the Koss Pro headphone frequency response characteristics applied to the sound. Results obtained from the analysis demonstrated that the generation of ultrasound can be the underlying reason for the treatment of the tinnitus.
这项工作的研究目的是分析被认为对耳鸣患者有积极影响的R. David Case声波的特征。此外,使用ktx Pro、ksc-75等特定耳机或耳机收听这些声波文件的参与者的耳鸣症状得到了缓解等健康状况的改善。因此,这些发现鼓励了R. David Case积极地追求他的旅程,去发现那些声音的特别之处,特别是当用Koss模型聆听时。在这项研究中,我们主要集中在R.大卫凯斯声音信号的技术方面,他已经记录。这些特定的声波被分析使用时域,频域以及效果使用科斯专业耳机的频率响应特性应用到声音。分析结果表明,超声的产生可能是耳鸣治疗的根本原因。
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引用次数: 0
Design of Digital Circuit Experiment Course Based on FPGA 基于FPGA的数字电路实验课程设计
Pub Date : 2021-03-30 DOI: 10.4236/WJET.2021.92024
Lei Zhao
With the development of integrated circuit, the content of digital circuit experiment course is constantly updated. In order to keep up with the development trend of the Times and make students’ professional knowledge meet the needs of the industry, the school adopts the FPGA experimental platform to carry out teaching reform from the two aspects of platform and experiment, and carry out reasonable experimental planning to enrich the experimental content. In this paper, the traditional knowledge points of logic algebra, trigger, timer, counter, decoder and digital tube are organically combined, and the digital clock system is designed and realized. The practice shows that the combination of modern design method and traditional digital circuit teaching method can play a good teaching effect. In this way, students can also fully learn, understand and skillfully use the new technology in the experiment, and in the process of building a comprehensive understanding of digital circuits.
随着集成电路的发展,数字电路实验课程的内容也在不断更新。为了跟上时代的发展趋势,使学生的专业知识适应行业的需要,学校采用FPGA实验平台,从平台和实验两个方面进行教学改革,并进行合理的实验规划,丰富实验内容。本文将传统的逻辑代数、触发器、定时器、计数器、解码器、数码管等知识点有机地结合起来,设计并实现了数字时钟系统。实践表明,现代设计方法与传统的数字电路教学方法相结合,能起到良好的教学效果。这样,学生也能在实验中充分地学习、理解和熟练地运用新技术,并在构建过程中对数字电路有一个全面的认识。
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引用次数: 0
Arm-Root Curve Fitting Based on Body Surface Feature Points for Young Male 基于体表特征点的青年男性臂根曲线拟合
Pub Date : 2021-03-30 DOI: 10.4236/WJET.2021.92017
Kaili Liu, Hongshu Jin
This paper is aiming to obtain an arm-root curve function performing the human arm-root size and shape realistically. A gypsum replica of upper arm for young male was made and scanned for extracting the 3D coordinates of 4 feature points of shoulder point, the anterior/posterior armpit point and the axillary point describing the real arm-root shape under the normalized definitions, and the 5 landmarks were confirmed additionally for improving the fitting precision. Then, the wholly and piecewise fitting of arm-root curve with 9 feature points and mark points in total were generated respectively based on least square polynomial fitting method. Comparing to the wholly fitting, the piecewise fitted function segmented by the line between anterior and posterior axillary points showed a high fitting degree of arm-root morphology with R-square of 1, the length difference between fitted curve and gypsum curve is 0.003 cm within error range. And it provided a basic curve model with standard feature points to simulate arm-root morphology realistically by curve fitting for accurate body measurement extraction.
本文的目的是得到一个真实地反映人体臂根尺寸和形状的臂根曲线函数。制作并扫描青年男性上臂石膏模型,提取归一化定义下描述真实臂根形状的肩点、腋窝前后点和腋窝点4个特征点的三维坐标,并对5个地标进行附加确认,提高拟合精度。然后,基于最小二乘多项式拟合方法,分别生成9个特征点和9个标记点的臂根曲线整体拟合和分段拟合;与整体拟合相比,以腋前后点连线分割的分段拟合函数对臂根形态拟合程度较高,r²为1,拟合曲线与石膏曲线的长度差在误差范围内为0.003 cm。并提供了具有标准特征点的基本曲线模型,通过曲线拟合逼真地模拟臂根形态,实现准确的体尺提取。
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引用次数: 1
Flexible Paper-Based Li-ion Batteries: A Review 柔性纸基锂离子电池研究进展
Pub Date : 2021-03-30 DOI: 10.4236/WJET.2021.92020
A. Ahmadian, Abbas Shafiee, Mohammadali Alidoost, A. Akbari
Lithium-ion (Li-ion) batteries have been fabricated in various ways to improve flexibility. Flexibility could be enhanced via active materials, separators, electrodes, and electrolytes, which could then be integrated to form flexible electronic devices with promising electrochemical properties compared to traditional non-flexible Li-ion batteries. Recent progress towards flexible Li- ion batteries fabrication, materials, and their electrochemical properties are investigated in this review. Additionally, recent developments in electronic devices utilizing flexible batteries and their future applications are explored. Portable and wearable electronics, as the primary beneficiaries of the flexible, rechargeable, and high-performance Li-ion batteries, are examined. In the end, various applications and challenges of flexible batteries in healthcare and various energy storage systems, considering practical implementation, are argued.
为了提高电池的灵活性,锂离子电池的制造方法多种多样。与传统的非柔性锂离子电池相比,可以通过活性材料、分离器、电极和电解质来增强柔性,然后将其集成成具有良好电化学性能的柔性电子设备。本文综述了近年来柔性锂离子电池的制备、材料及其电化学性能的研究进展。此外,还探讨了利用柔性电池的电子设备的最新发展及其未来的应用。便携式和可穿戴电子产品,作为柔性,可充电和高性能锂离子电池的主要受益者,进行了检查。最后,讨论了柔性电池在医疗保健和各种储能系统中的各种应用和挑战,考虑到实际实施。
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引用次数: 17
期刊
World Journal of Engineering and Technology
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