检索结果-南通市图书馆

Improving resource-constrained IoT device lifetimes by mitigating redundant transmissions across heterogeneous wireless multimedia of things

引用

Digital Communications and Networks 2022年第5期8卷 778-790页

作者： Muhammad Salah ud din Muhammad Atif Ur Rehman Rehmat Ullah Chan-Won Park dae ho kim Byung-seo kim Department of Electronics&Computer Engineering Hongik UniversitySejong City30016South Korea Department of Computing&Mathematics Manchester Metropolitan University United Kingdom Cardiff School of Technologies Cardiff Metropolitan UniversityCardiffCF52YBUnited Kingdom Electronics and Telecommunications Research Institute Daejeon34129South Korea Department of Software and Communications Engineering Hongik UniversitySejong City30016South Korea

In Wireless Multimedia Sensor Networks(WMSNs),nodes capable of retrieving video,audio,images,and small scale sensor data,tend to generate immense traffic of various *** energy-efficient transmission of such a vast amount of heterogeneous multimedia content while simultaneously ensuring the quality of service and optimal energy consumption is ***,we propose a Power-Efficient Wireless Multimedia of Things(PE-WMoT),a robust and energy-efficient cluster-based mechanism to improve the overall lifetime of *** a PE-WMoT,nodes declare themselves Cluster Heads(CHs)based on available *** cluster formation and CH declaration processes are completed,the Sub-Cluster(SC)formation process triggers,in which application base nodes within close vicinity of each other organize themselves under the administration of a Sub-Cluster Head(SCH).The SCH gathers data from member nodes,removes redundancies,and forwards miniaturized data to its respective ***-WMoT adopts a fuzzy-based technique named the analytical hierarchical process,which enables CHs to select an optimal SCH among available SCs.A PE-WMoT also devises a robust scheduling mechanism between CH,SCH,and child nodes to enable collision-free data *** results revealed that a PE-WMoT significantly reduces the number of redundant packet transmissions,improves energy consumption of the network,and effectively increases network throughput.

关键词： Clustering WMSN WSN IoTs Resource-constrained Fuzzy AHP Sub clustering MAC Energy efficiency Network lifetime

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Study on Broadband Multi-hole Directional Coupler

A Study on Broadband Multi-Hole Directional Coupler

引用

2002 3rd International Conference on Microwave and Millimeter Wave Technology

作者： dae-ho kim Chan-Wook Baik Seok-Gi Jeon Gun-Sik Park School of Physics Seoul National University 151-742SeoulKorea

ISBN: (纸本)078037486X

＜正＞The conventional theories of waveguide directional coupler including Bethe’s theory,correction theory and multi-hole array theory,can be a good start for designing very tight multi-hole coupler with square coupling *** with the conventional theory and HFSS,modified Cohn’s empirical factor of thickness attenuation was obtained.A OdB-waveguide multi-hole coupler（X-band） is fabricated and the calculated coupling and directivity are compared with HFSS simulation and measured value showing a good agreement.

关键词： directional couplers circuit simulation circuit CAD waveguide theory broadband multi-hole directional waveguide coupler study Bethe theory waveguide correction theory multi-hole array theory square coupling apertures HFSS simulation high frequency structure simulator Cohn empirical thickness attenuation factor X-band multi-hole coupler directivity/coupling

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Apolipoprotein A-I binding protein-mediated neuroprotection in glaucomatous neuroinflammation and neurodegeneration

引用

Neural Regeneration Research 2025年第5期20卷 1414-1415页

作者： Sinwoo Hwang Seunghwan Choi Soo-ho Choi Keun-Young kim Yury I.Miller Won-Kyu Ju Hamilton Glaucoma Center and Shiley Eye Institute The Viterbi Family Department of OphthalmologyUniversity of California San DiegoLa JollaCAUSA Department of Medicine University of California San DiegoLa JollaCAUSA National Center for Microscopy and Imaging Research Department of NeurosciencesUniversity of California San DiegoLa JollaCAUSA

Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs *** to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more *** primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.

关键词： irreversible pass primarily

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimization of post-warranty sequential inspection for second-hand products

引用

Journal of Systems Engineering and Electronics 2017年第4期28卷 793-800页

作者： dae-Kyung kim Jae-Hak Lim Dong ho Park Department of Statistics Chonbuk National University Department of Management & Accounting Hanbat National University Industry Academic Cooperation Foundation Hallym University

This paper considers an optimal sequential inspection schedule for a second-hand product after that the free nonrenewable warranty is expired. The length of warranty is prespecified and during the warranty period, the product is minimally repaired by the dealer when it fails. Following the expiration of the non-renewing warranty, the product is inspected and upgraded sequentially a fixed number of times at the expenses of the *** each inspection, the failure rate of the product is reduced proportionally so that the product is upgraded. The product is assumed to deteriorate as it ages and the replacement of the product occurs when a fixed number of inspections are rendered. In addition,the intervals between two successive inspections are assumed to decrease monotonically. The main objective of this paper is to determine the optimal improvement level to upgrade the product at each inspection so that the expected maintenance cost during the life cycle of the product is minimized from the perspective of the customer. Under the given cost structures, we derive an explicit formula to obtain the expected maintenance cost incurred during the life cycle of the product and discuss the method to find the optimal level of the improvement analytically in case the failure times follow the Weibull distribution. Numerical results are analyzed to observe the impact of relevant parameters on the optimal solution.

关键词： second-hand product sequential inspection upgrade action life cycle of the product expected maintenance cost free non-renewable warranty

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ag-GST/HfO_(x)-based unidirectional threshold switching selector with low leakage current and threshold voltage distribution for high-density cross-point arrays

引用

Rare Metals 2024年第1期43卷 280-288页

作者： Kyoung-Joung Yoo dae-Yun Kang Nahyun kim ho-Jin Lee Ta-Hyeong kim Taeho kim Tae Geun kim School of Electrical Engineering Korea UniversitySeoul 02841Republic of Korea

The use of electrochemical-metallization-based volatile threshold switching selectors in cross-point arrays has been widely explored owing to their high on-off ratios and simple ***,these devices are unsuitable for cross-point architectures because of the difficulty in controlling the random filament formation that results in large fluctuations in the threshold voltage during *** this study,we investigated the unidirectional threshold transition characteristics associated with an Ag/GST/HfO_(x)/Pt-based bilayer selector and demonstrated the occurrence of a low leakage current(hold voltage(Δ0.11 V).The bilayer structure could control the filament formation in the intermediate state through the insertion of an HfO_(x) tunneling *** stacking a bilayer selector with NiO_(x)based resistive random-access memory,the leakage and programming currents of the device could be significantly *** the crossbar array configuration,we performed equivalent circuit analysis of a one-selector oneresistor(1S1R) devices and estimated the optimal array size to demonstrate the applicability of the proposed *** maximum acceptable crossbar array size of the 1S1R device with the Ag/GST/HfO_(x)/Pt/Ti/NiO_(x)/Pt structure was 5.29×10^(14)(N^(2),N=2.3×10^(7)).

关键词： Selector device Tunneling barrier Threshold switching Sputtering 1S1R Cross-point array

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dual in-situ observation of tribochemical and morphological evolution of single-layer WS_(2)and multi-layer WS_(2)/C coatings

引用

Friction 2024年第7期12卷 1580-1598页

作者： Yuzhen LIU Jae-ho HAN Shusheng XU Young Chan JUNG dae-Eun kim State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Department of Mechanical Engineering Yonsei UniversitySeoul03722Republic of Korea Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 264000China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Yantai 264000China

The outstanding tribological performance of transition metal dichalcogenides(TMDs)is attributed to their unique sandwich microstructure and low interlayer shear *** advantageous structure allows TMDs to demonstrate exceptional friction reduction ***,the incorporation of TMDs and amorphous carbon(a-C)in multi-layer structures shows excellent potential for further enhancing tribological and anti-oxidation *** carbon,known for its high ductility,chemical inertness,and excellent wear resistance,significantly contributes to the overall performance of these multi-layer *** gain an in-depth understanding of the tribological mechanism and evolution of TMDs’multi-layer coatings,a dual in-situ analysis was carried out using a tribometer equipped with a 3D laser microscope and a Raman *** innovative approach allowed for a comprehensive evolution of the tribological,topographical,and tribochemical characteristics of both single-layer WS_(2)and multi-layer WS_(2)/C coatings in real *** findings from the dual in-situ tribotest revealed distinct failure characteristics between the single-layer WS_(2)coating and the multi-layer WS_(2)/C *** single-layer WS_(2)coating predominantly experienced failure due to mechanical removal,whereas a combination of mechanical removal and tribochemistry primarily influenced the failure of the multi-layer WS_(2)/C *** tribological evolution process of these two coatings can be classified into four stages on the basis of their tribological behavior:the running-in stage,stable friction stage,re-deposition stage,and lubrication failure *** stage represents a distinct phase in the tribological behavior of the coatings and contributes to our understanding of their behavior during sliding.

关键词： In-situ analysis multi-layer coating tribology tribochemistry

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A novel strategy for gas mitigation during swine manure odour treatment using seaweed and a microbial consortium

引用

Frontiers of Environmental Science & Engineering 2020年第3期14卷 203-214页

作者： Madhavaraj Lavanya ho-Dong Lim Kong-Min kim dae-Hyuk kim Balasubramani Ravindran Gui Hwan Han Center for Industrialization of Agricultural and Livestock Microorganisms(CIALM) Jeongeup-si 56212Republic of Korea Department of Molecular Biology Institute for Molecular Biology and GeneticsJeonbuk National UniversityJeonju 561-756Republic of Korea Department of Environmental Energy&Engineering Kyonggi UniversitySuwon-si 16227Republic of Korea

Gas emissions from swine farms have an impact on air quality in the Republic of *** manure stored in deep pits for a long time is a major source of harmful gas ***,we evaluated the mitigation of emissions of ammonia(N H 3),hydrogen sulfide(H2S)and amine gases from swine manure with biological products such as seaweed(Sargassum homeri)and a microbial consortium(Bacillus subtilis(1.2×10^9 CFU/mL),Thiobacillus sp.(1.0×10^10 CFU/mL)and Saccharomyces cerevisiae(2.0×10^9 CFU/mL))used as additives due to their promising benefits for nutrient ***,seaweed powder masking over two days provided notable control of over 98%-100%of the gas ***,significant control of gas emissions was especially pronounced when seaweed powder masking along with a microbial consortium was applied,resulting in a gas reduction rate of 100%for NH 3,amines and H2S over 10 days of *** results also suggested that seaweed powder masking and a microbial consortium used in combination to reduce the gas emissions from swine manure reduced odour compared with that observed when the two additives were used *** the consortium,seaweed decreased total volatile fatty acid(VFA)*** proposed novel method of masking with a microbial consortium is promising for mitigating hazardous gases,simple,and environmentally *** research is warranted to determine the mechanisms underlying the seaweed and substrate interactions.

关键词： Seaweed Consortium Mitigation Ammonia H2S Volatile fatty acids(VFAs)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comparison Between Full-Scale and Model Experiments of Oil Fences

引用

China Ocean Engineering 2009年第4期23卷 657-668页

作者： Tae ho kim Duck Jong JANG Kyong Uk YANG Sun Chol NA dae An kim School of Marine Technology Chonnam National UniversityYeosu Department of Maritime Police Science Chonnam National UniversityYeosu Korea Marine Environment Management Corporation

This study examines the performance of an air expansion oil fence system as deployed in two different configurations. Geometric and tension characteristics of the oil fence are investigated for （1） the system attached to two vessels and （2） the system attached to one vessel with spreading devices. Since full-scale testing can be time consuming and expensive, another component of the study was to examine how well models would perform. A scaling technique was developed and a set of experiments were conducted with a 1/20-th scale model of the oil fence in a towing tank facility. Performance resalts from the model tests were compared with those conducted at sea. The tension （N） in the full-scale results were represented by R = avb, where v is the current velocity in m/s and the values for a and b used for comparison purposes. Both sets of full-scale and model tests were conducted with an oil fence opening of 120 m and 160m. In the full-scale experiment with spreading devices attaahed to the forward ends of the oil fence, the horizontal distance of the spreading devices has a tendency to linearly increase as the current velocity increases when the warp length is as short as 50 m, but to linearly decrease as the current velocity increases when the warp length is extended to 100 m and 150 m. The spreading distance at uniform current velocitys in the model test increases as the warp length is extended. While there is no significant difference of spreading distance between the cases of 100 m and 150 m, the spreading distance becomes shorter when the warp length is 50 m.

关键词： oil fence spreading devices tension horizontal distance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

One-step method to enhance biotribological properties and biocompatibility of DLC coating by ion beam irradiation

引用

Friction 2022年第7期10卷 1114-1126页

作者： Yuzhen LIU Kelun ZHANG Jae-ho HAN Youn-hoo HWANG Shusheng XU dae-Eun kim Department of Mechanical Engineering Yonsei UniversitySeoul 03722Republic of Korea Department of Dermatology and Cutaneous Biology Research Institute Yonsei University College of MedicineSeoul 03722Republic of Korea State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

A one-step method was developed to create a highly biocompatible micropatterned surface on a diamond-like carbon(DLC)through irradiation with a nitrogen ion beam and thus enhance the biocompatibility of osseointegrated surfaces and biotribological performance of articular *** biocompatibility and biotribological mechanisms were analyzed in terms of the structure and morphology of *** was demonstrated that a layer enriched in sp^(3) C-N bonds was formed on the surface of the DLC after nitrogen ion beam ***,with an increase in the radiation dose,the content of sp^(3) C-N on the DLC surface increased significantly,and the biocompatibility was positively correlated with *** adhesion of the MC3T3 osteoblasts increased significantly from 32%to 86%under an irradiation dose of 8×10^(15) ions/cm^(2).In contrast,the micropattern had a significant negative effect on the adhesion of the osteoblasts as it physically hindered cell expansion and *** micropattern with a depth of 37 nm exhibited good friction properties,and the coefficient of friction was reduced by 21%at relatively high speeds.

关键词： ion beam irradiation biocompatibility diamond-like carbon(DLC) in-vivo micropattern biotribological performance

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Identifying the relationships between subsurface absorber defects and the characteristics of kesterite solar cells

引用

Carbon Energy 2023年第8期5卷 42-54页

作者： dae-ho Son Dong-Hwan Jeon dae-Hwan kim Jin-Kyu Kang Shi-Joon Sung Jaebaek Lee Taeseon Lee Enkhjargal Enkhbayar Junho kim Kee-Jeong Yang Division of Energy Technology DGISTDaeguRepublic of Korea Research Center for Thin Film Solar Cells DGISTDaeguRepublic of Korea Department of Physics Incheon National UniversityIncheonRepublic of Korea

Understanding the defect characteristics that occur near the space-charge regions(SCRs)of kesterite(CZTSSe)solar cells is important because the recombination loss at the CZTSSe/CdS interface is considered the main cause of their low *** surfaces with different elemental compositions were formed without polishing(C00)and with polishing for 20 s(C20)and 60 s(C60).For C60,a specific region near the SCR was excessively Cu-rich and Zn-poor compared to C00 and *** charged defects formed where the elemental variation was *** the main deep acceptor defect energy level(E_(a2))near the SCR increased,the efficiency,open-circuit voltage deficit,and current density degraded,and this phenomenon was especially rapid for large E_(a2) *** the E_(a2) near the SCR became deep,the carrier diffusion length decreased more for the CZTSSe solar cells with a low carrier mobility than for the CuInGaSe_(2)(CIGSe)solar *** large amplitude of the electrostatic potential fluctuation in the CZTSSe solar cells induced a high carrier recombination and a short carrier ***,the properties of the CZTSSe solar cells were more strongly degraded by defects with deep energy levels near the SCR than those of the CIGSe solar cells.

关键词： defect density defect energy level elemental variation kesterite space charge region

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：