• Earthquakes and Structures
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• 제15권5호
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• pp.541-553
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• 2018

In this paper a limit analysis based procedure for the rapid evaluation of the in-plane seismic capacity of masonry arch bridges is carried out. Attention has been paid to the effect of the backfill on the collapse load. A parametric investigation has been performed by varying the rise/span ratio and the results have been compared with those obtained by finite element modelling. The comparison highlights the conservative feature of the proposed model in terms of ultimate loads and a good agreement in terms of collapse mechanisms.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.273-276
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• 2008

As the rapid and various changing of social aspects, the structures are getting bigger, higher and more complex. The importance of evacuation is on the rise as increased using frequency of multiplex sale facility and it's high population density. According to the result of a survey with 4 domestic wholesales mart's population density, the average and maximum was 0.41(人/$m^2$) and 0.46(人/$m^2$). considering evacuation dangerousness, the maximum value will be suitable for computation of evacuation capacity and this will be submitted as a basic data for computation of evacuation capacity.

• Steel and Composite Structures
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• 제19권6호
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• pp.1355-1367
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• 2015

Steel conical shells have long been used in various parts of different structures. Sensitivity to the initial geometrical imperfection has been one of the most significant issues on the stability of these structures, which has made them highly vulnerable to the buckling. Most attention has been devoted to structures under normal fabrication related imperfections. Notwithstanding, the challenges of large local imperfections - presented herein as dent-shaped imperfections - have not been a focus yet for these structures. This study aims to provide experimental data on the effect of such imperfections on the buckling capacity of these shells under axial compression. The results show changes in the buckling mode and the capacity for such damaged thin specimens as is outlined in this paper, with an average overall capacity reduction of 11%.

• Journal of Electrochemical Science and Technology
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• 제13권3호
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• pp.339-346
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• 2022

Silicon (Si) has attracted considerable attention due to its high theoretical capacity compared to conventional graphite anode materials. However, Si-based anode materials suffer from rapid capacity loss due to mechanical failure caused by large volume change during cycling. To alleviate this phenomenon, crosslinked polymeric binders with strong interactions are highly desirable to ensure the electrode integrity. In this study, thermally crosslinked polyimide binders were used for Si-alloy anodes in Li-ion batteries. The crosslinked polyimide binder was found to have high adhesion strength, resulting in enhanced electrode integrity during cycling. Therefore, the Si-alloy anodes with crosslinked polyimide binder provide enhanced electrochemical performance, such as Coulombic efficiency, capacity retention, and cycle stability.

• Asian Journal for Public Opinion Research
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• 제3권1호
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• pp.1-21
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• 2015

A recent public opinion survey found that the anti-corporate sentiment of South Korean citizens is primarily due to the misbehavior of Korean corporations. South Korean citizens' skepticism of corporations may hinder the democratic and economic development of the country. As a driving force for community development, social capital is considered to enable citizens to collaborate with one another to resolve a shared problem. Specifically, this study pays attention to the relationship among social capital, corporate capacity, and trust, which may perhaps contribute to developing a democratic environment in Korean society. The study aims to explore whether Korean citizens' perceived corporate bonding and bridging social capital affect corporate capacity for collaborative action and trust in corporations. A Web survey of 385 South Koreans was conducted. The findings show that perceived bonding social capital among employees is positively related to corporate capacity for collaboration action. Moreover, perceived bonding among employees and bridging social capital between employees and local residents are positively related to corporate capacity for collaboration action and trust in corporations. These findings suggest that researchers and practitioners for organizational development and community-building need to enhance corporate social capital.

• Structural Engineering and Mechanics
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• 제65권5호
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• pp.601-609
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• 2018

Steel bolts are used in the construction industry for a large variety of applications that range from fixing permanent installations to temporary fixtures. In the past much research has been focused on developing destructive testing techniques to estimate their pull-out load carrying capacity with very little attention to develop non-destructive techniques. In this regards the presented research work details the combined use of ultrasonic pulse velocity and Schmidt hammer tests to identify anchor bolts with faculty installation and to estimate their pull-out strength by relating it to the Schmidt hammer rebound value. From experimentation, it was observed that the load capacity of bolt depends on its embedment length, diameter, bond quality/concrete strength and alignment. Ultrasonic pulse velocity test is used to judge the quality of bond of embedded anchor bolt by relating the increase in ultrasonic pulse transit time to the presence of internal pours and cracks in the vicinity of steel bolt and the surrounding concrete. This information combined with the Schmidt hammer rebound number, R, can be used to accurately identify defective bolts which resulted in lower pull-out strength. 12 mm diameter bolts with embedment length of 70 mm and 50 mm were investigated using constant strength concrete. Pull-out load capacity versus the Schmidt hammer rebound number for each embedment length is presented.

• 한국경영정보학회:학술대회논문집
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• 한국경영정보학회 2008년도 춘계학술대회
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• pp.525-540
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• 2008

With the competitive pressure and the development of information and communication technology, many organizations have introduced various kinds of enterprise-wide systems like enterprise resource planning (ERP) systems as strategic tools for the purpose of improving organizational performance. Despite their promised strategic benefits, however, their implementation has suffered from a high failure rate and difficulty in realizing the anticipated benefits. Previous studies have indicated that one of the most critical failure reasons is the lack of knowledge sharing and utilization across organizations. As a consequence, many information systems (IS) researchers have paid attention to examining the effect of absorptive capacity closely associated with knowledge sharing and transferring on IS usage performance. ERP systems implementation involves changes not only in systems but also in processes and other social dimensions, which can be related to organizational citizenship behavior (OCB) requiring appropriate communications and interactions among organizational members. A lack of communications and interactions due to a lack of OCB might lead to weak absorptive capacity and thus negatively influence knowledge sharing across organizations, because OCB facilitates a successful collaboration among functional units and positively impacts individual's attitude toward radical organizational change. With this motivation, this study has two research objectives. First, it introduces and tests a theoretical model accounting for the relationships among performance of ERP system usage, absorptive capacity, and OCB. Second, it examines a mediating role of absorptive capacity between OCB and performance of EPR system usage. Theoretical and practical implications of the study ware discussed, along with its limitations.

• 융복합기술연구소 논문집
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• 제4권1호
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• pp.5-8
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• 2014

Recently ionic liquids received much attention as novel materials capable of replacing traditional solvents. The applicability of the ionic liquids should be determined based on their physico-chemical properties. Heat capacity is one of the most important properties to be considered when a process is developed using the ionic liquids and currently DSC has been proved as an effective technique to measure the heat capacity. Micro DSCII can measure heat capacities of various liquids by both an isothermal step method and a scanning method. DSC Q100 and MDSC are able to measure heat capacities of several ionic liquids. For each ionic liquid linear regression of the heat capacity as a function of temperature has been performed to increase accuracy. To investigate the feasibility of ionic liquids as PCMs, their heat capacities have been measured by using Pysis I DSC. This paper briefly summarizes the present techniques of measuring heat capacities of ionic liquids by DSC.

• 한국분말재료학회지
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• 제25권6호
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• pp.466-474
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• 2018

The high theoretical energy density ($2600Wh\;kg^{-1}$) of Lithium-sulfur batteries and the high theoretical capacity of elemental sulfur ($1672mAh\;g^{-1}$) attract significant research attention. However, the poor electrical conductivity of sulfur and the polysulfide shuttle effect are chronic problems resulting in low sulfur utilization and poor cycling stability. In this study, we address these problems by coating a polyethylene separator with a layer of activated carbon powder. A lithium-sulfur cell containing the activated carbon powder-coated separator exhibits an initial specific discharge capacity of $1400mAh\;g^{-1}$ at 0.1 C, and retains 63% of the initial capacity after 100 cycles at 0.2 C, whereas the equivalent cell with a bare separator exhibits a $1200mAh\;g^{-1}$ initial specific discharge capacity, and 50% capacity retention under the same conditions. The activated carbon powder-coated separator also enhances the rate capability. These results indicate that the microstructure of the activated carbon powder layer provides space for the sulfur redox reaction and facilitates fast electron transport. Concurrently, the activated carbon powder layer traps and reutilizes any polysulfides dissolved in the electrolyte. The approach presented here provides insights for overcoming the problems associated with lithium-sulfur batteries and promoting their practical use.

• 감성과학
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• 제18권2호
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• pp.3-18
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• 2015

인간의 수량지각은 선천적인 능력으로 생각되지만 그 민감도에 있어서는 개인차가 존재할 가능성이 크다. 본 연구는 시각작업기억과 시각탐색 효율성 그리고 수량민감도 능력 간의 상관 여부를 조사하였다. 이를 위해 변화탐지 수행 능력에 기초해 개인의 작업기억 저장용량을 정량화시킨 K-값, 시각탐색 효율성의 지표인 탐색함수의 기울기 그리고 두 점 배열내의 점 개수 간 수량 차이에 대한 민감도를 각각 측정하였다. 이들에 대한 상관 관계분석 결과 시각작업기억 고용량 개인의 경우 점 배열 간 위치 정보가 보전되었을 때 수량 차이에 상대적으로 저용량 개인에 비해 민감했던 반면, 시각탐색 고효율 개인의 경우 점 배열 간 위치 정보가 보전되지 않았을 때 수량 차이에 상대적으로 민감했다. 이러한 결과는 작업기억 고용량 개인들의 경우 점배열을 소수의 점 패턴 형태로 군집화하는 책략을 사용했을 가능성과 함께, 고효율 시각탐색이 가능한 개인들은 배열 내의 개별 점들에 대해 초점 주의를 상대적으로 신속하게 이용하는 책략을 사용했을 가능성을 시사한다. 종합해 볼 때, 개인들의 수량 민감도는 개인의 작업기억 용량 및 초점주의 이동의 효율성에 의존할 가능성이 있는 것으로 판단된다.