检索结果-南通市图书馆

High efficiency CZTSSe solar cells enabled by dual Ag-passivation approach via aqueous solution process

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2023年第2期77卷 239-246,I0007页

作者： Temujin Enkhbat Enkhjargal Enkhbayar Namuundari Otgontamir Md Hamim Sharif Md Salahuddin Mina Seong Yeon kim junho kim Department of Physics Incheon National UniversityIncheon 22012Republic of Korea Research Center for Thin Film Solar Cells Daegu-Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Global Energy Research Center for Carbon Neutrality Incheon National UniversityIncheon 22012Republic of Korea

Ag substitution in Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)is a promising way to mitigate Cu/Zn related defects,electrostatic fluctuations and Shockley-Read-Hall(SRH)recombination ***,high performance ACZTSSe solar cells are generally demonstrated with more Ag amounts and strenuous fabrication processes,which are not ideal when using cheap constituent materials *** reduce the Ag amount(2%-3%),local Ag substitutions into CZTSSe at front(F),back(B)and dual front/back(FB)were *** results revealed that F-passivation effectively reduced the Cu/Zn related defects and further limits the interface/bulk recombination whereas B-passivation improved the grain growth at the back interface and further allows enhanced transport of charge *** employing the dual Agpassivation approach,the final ACZTSSe device parameters were significantly improved and remarkable power conversion efficiency(PCE)of 12.43%was achieved with eco-friendly aqueous solution process.

关键词： Ag-doped CZTSSe Dual surface passivation Defect passivation Aqueous spray deposition

Topology evolutions of silhouettes

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

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1671-1680页

作者： DAI Jun-fei kim junho ZENG Hua-yi GU Xian-feng YAU Shing-tung Center of Mathematical Sciences Zhejiang University Hangzhou 310027 China Visualization Laboratory State University of New York Stony Brook NY 11794 USA Department of Mathematics Harvard University Boston MA02138 USA

We give the topology changing of the silhouette in 3D space while others study the projections in an image. Silhou- ettes play a crucial role in visualization, graphics and vision. This work focuses on the global behaviors of silhouettes, especially their topological evolutions, such as splitting, merging, appearing and disappearing. The dynamics of silhouettes are governed by the topology, the curvature of the surface, and the view point. In this paper, we work on a more theoretical level to give enu- merative properties of the silhouette including: the integration of signed geodesic curvature along a silhouette is equal to the view cone angle; in elliptic regions, no silhouette can be contained in another one; in hyperbolic regions, if a silhouette is homotopic to a point, then it has at least 4 cusps; finally, critical events can only happen when the view point is on the aspect surfaces (ruled surface of the asymptotic lines of parabolic points with surface itself). We also introduce a method to visualize the evolution of silhouettes, especially all the critical events where the topologies of the silhouettes change. The results have broad applications in computer vision for recognition, graphics for rendering and visualization.

关键词： Topological change Silhouette Geodesic curvature Cusp

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

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

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

Understanding of the Relationship between the Properties of Cu(In,Ga)Se_(2) Solar Cells and the Structure of Ag Network Electrodes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第6期7卷 246-253页

作者： Hyesun Yoo Hoang Van Quy Inpyo Lee Seung Taek Jo Tae Ei Hong junho kim Dae-Hwang Yoo Jinwook Shin Walter Commerell Dae-Hwan kim Jong Wook Roh Regional Leading Research Center(RLRC)of Smart Energy System Kyungpook National UniversityGyeongsangbuk-do 37224Korea Division of Energy Technology DaeguGyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Korea Department of Hydrogen and Renewable Energy Kyungpook National UniversityDaegu 47922Korea Nano Photoelectronic Device Lab Department of PhysicsIncheon National UniversityIncheon 22012Korea Institute for Energy and Drive Technology Technische Hochschule Ulm(THU)Ulm 89081Germany Department of Nano&Advanced Materials Science and Engineering Kyungpook National UniversityGyeongsangbuk-do 37224Korea

The relation between the structure of the silver network electrodes and the properties of Cu(In,Ga)Se_(2)(CIGS)solar cells is systemically *** Ag network electrode is deposited onto an Al:ZnO(AZO)thin film,employing a self-forming cracked *** control over the cracked template's structure is achieved through careful adjustment of temperature and *** Ag network electrodes with different coverage areas and network densities are systemically applied to the CIGS solar *** is revealed that predominant fill factor(FF)is influenced by the figure of merit of transparent conducting electrodes,rather than sheet resistance,particularly when the coverage area falls within the range of 1.3–5%.Furthermore,a higher network density corresponds to an enhanced FF when the coverage areas of the Ag networks are *** utilizing a thinner AZO film,CIGS solar cells with a surface area of 1.0609 cm^(2)exhibit a notable performance improvement,with efficiency increasing from 10.48%to 11.63%.This enhancement is primarily attributed to the increase in FF from 45%to 65%.These findings underscore the considerable potential for reducing the thickness of the transparent conductive oxide(TCO)in CIGS modules with implications for practical applications in photovoltaic technology.

关键词： CIGS large-area solar cell metal mesh metallic network transparent electrode

Vertical plane depth-resolved surface potential and carrier separation characteristics in flexible CZTSSe solar cells with over 12% efficiency

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Carbon Energy 2024年第3期6卷 36-52页

作者： Dae-Ho Son Ha Kyung Park Dae-Hwan kim Jin-Kyu Kang Shi-Joon Sung Dae-Kue Hwang Jaebaek Lee Dong-Hwan Jeon Yunae Cho William Jo Taeseon Lee junho kim Sang-Hoon Nam Kee-Jeong Yang Division of Energy Technology DGISTDaeguRepublic of Korea Research Center for Thin Film Solar Cells DGISTDaeguRepublic of Korea Department of Physics Ewha Womans UniversitySeoulRepublic of Korea Department of Physics Incheon National UniversityIncheonRepublic of Korea Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMassachusettsUSA

Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic *** main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and *** overcome this,it is important to understand their electron-hole behavior *** determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber *** elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)*** the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was *** the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was *** improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable.

关键词： carrier separation CZTSSe flexible solar cell local current surface potential

Systematic Security Guideline Framework through Intelligently Automated Vulnerability Analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第3期78卷 3867-3889页

作者： Dahyeon kim Namgi kim junho Ahn Computer Information Technology Korea National University of TransportationChungju27469Korea Department of AI Computer Science and Engineering Kyonggi UniversitySuwon16227Korea

This research aims to propose a practical framework designed for the automatic analysis of a product’s comprehensive functionality and security vulnerabilities,generating applicable guidelines based on real-world *** existing analysis of software security vulnerabilities often focuses on specific features or *** partial and arbitrary analysis of the security vulnerabilities makes it challenging to comprehend the overall security vulnerabilities of the *** key novelty lies in overcoming the constraints of partial *** proposed framework utilizes data from various sources to create a comprehensive functionality profile,facilitating the derivation of real-world security *** guidelines are dynamically generated by associating functional security vulnerabilities with the latest Common Vulnerabilities and Exposure(CVE)and Common Vulnerability Scoring System(CVSS)scores,resulting in automated guidelines tailored to each *** guidelines are not only practical but also applicable in real-world software,allowing for prioritized security *** proposed framework is applied to virtual private network(VPN)software,wherein a validated Level 2 data flow diagram is generated using the Spoofing,Tampering,Repudiation,Information Disclosure,Denial of Service,and Elevation of privilege(STRIDE)technique with references to various papers and examples from related *** analysis resulted in the identification of a total of 121 *** successful implementation and validation demonstrate the framework’s efficacy in generating customized guidelines for entire systems,subsystems,and selected modules.

关键词： Framework automation vulnerability analysis security guidelines

Intelligent SLAM Algorithm Fusing Low-Cost Sensors at Risk of Building Collapses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2023年第1期74卷 1657-1671页

作者： Dahyeon kim junho Ahn Computer Information Technology Korea National University of TransportationChungju27469Korea

When firefighters search inside a building that is at risk of collapse due to abandonment or disasters such as fire,they use old architectural drawings or a simple monitoring method involving a video device attached to a ***,using these methods,the disaster situation inside a building at risk of collapse is difficult to detect and ***,we investigate the generation of digital maps for a disaster site to accurately analyze internal *** this study,a robot combined with a low-cost camera and twodimensional light detection and ranging(2D-lidar)traverses across a floor to estimate the location of obstacles while drawing an internal map of the *** propose an algorithm that detects the floor and then determines the possibility of entry,tracks collapses,and detects obstacles by analyzing patterns on the *** robot’s location is estimated,and a digital map is created based on Hector simultaneous localization and mapping(SLAM).Subsequently,the positions of obstacles are estimated based on the range values detected by 2D-lidar,and the position of the obstacles are identified on the map using the map update method in semantic *** equipment are implemented using low-specification devices,and the experiments are conducted using a low-cost robot that affords near-real-time *** experiments are conducted in various actual internal environments of *** terms of obstacle detection performance,almost all obstacles are detected,and their positions identified on the map with a high accuracy of 89%.

关键词： Intelligence SLAM vision 2D-lidar low-cost algorithm

Vision-based Recognition Algorithm for Up-To-Date Indoor Digital Map Generations at Damaged Buildings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第8期72卷 2765-2781页

作者： Dahyeon kim Chulsu kim junho Ahn Computer Information Technology Korea National University of TransportationChungju27469Korea Department of Railway Vehicle System Engineering Korea National University of TransportationUiwang16106Korea

When firefighters are engaged in search and rescue missions inside a building at a risk of collapse,they have difficulty in field command and rescue because they can only simplymonitor the situation inside the building utilizing old building drawings or *** propose an efficient solution for fast search and rescue work of firefighters,this study investigates the generation of up-to-date digital maps for disaster sites by tracking the collapse situation,and identifying the information of obstacles which are risk factors,using an artificial intelligence algorithm based on low-cost *** research separates the floor by using the mask regional convolutional neural network(R-CNN)algorithm,and determines whether the passage is collapsed or ***,in the case of a passage that can be searched,the floor pattern of the obstacles that exist on the floor that has not collapsed is analyzed,and obstacles are searched utilizing an image processing ***,we can detect various unknown as well as known ***,the locations of obstacles can be estimated using the pixel values up to the bounding box of an existing detected *** conduct experiments using the public datasets collected by Carnegie Mellon university(CMU)and data collected by manipulating a low-cost robot equipped with a smartphone while roaming five buildings in a *** collected data have various floor patterns for objectivity and obstacles that are different from one *** on these data,the algorithm for detecting unknown obstacles of a verified study and estimating their sizes had an accuracy of 93%,and the algorithm for estimating the distance to obstacles had an error rate of *** this process,we tracked collapsed passages and composed up-to-date digital maps for disaster sites that include the information of obstacles that interfere with the search and rescue work.

关键词： Vision artificial intelligence robot map generation damaged building

Multiple-patterning colloidal lithography-implemented scalable manufacturing of heat-tolerant titanium nitride broadband absorbers in the visible to near-infrared

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2021年第2期7卷 51-58页

作者： Dasol Lee Myeongcheol Go Minkyung kim junho Jang Chungryong Choi Jin Kon kim Junsuk Rho Department of Mechanical Engineering Pohang University of Science and Technology(POSTECH)Pohang37673Republic of Korea Department of Chemical Engineering Pohang University of Science and Technology(POSTECH)Pohang37673Republic of Korea National Institute of Nanomaterials Technology(NINT) Pohang37673Republic of Korea

Broadband perfect absorbers have been intensively researched for decades because of their near-perfect absorption optical property that can be applied to diverse applications. Unfortunately, achieving large-scale and heat-tolerant absorbers has been remained challenging work because of costly and time-consuming lithography methods and thermolability of materials, respectively. Here, we demonstrate a thermally robust titanium nitride broadband absorber with >95% absorption efficiency in the visible and near-infrared region (400–900 nm). A relatively large-scale (2.5 cm × 2.5 cm) absorber device is fabricated by using a fabrication technique of multiple-patterning colloidal lithography. The optical properties of the absorber are still maintained even after heating at the temperatures >600 ∘C. Such a large-scale, heat-tolerant, and broadband near-perfect absorber will provide further useful applications in solar thermophotovoltaics, stealth, and absorption controlling in high-temperature conditions.

关键词： absorber titanium absorption