• Steel and Composite Structures
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• v.38 no.4
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• pp.365-380
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• 2021

Although traditional steel-concrete composite beams have excellent structural characteristics, it cannot meet the requirement of quick assembly and repair in the engineering. This paper presents a study on static behavior of bolt connected steel-concrete composite beam without post-cast zone. A three-dimensional finite element model was developed with its accuracy and reliability validated by available experimental results. The analysis results show that in the normal service stage, the bolt is basically in the state of unidirectional stress with the loss of pretightening can be ignored. Parametric studies are presented to quantify the effects of the post-cast zone, size and position of splicing gap on the behavior of the beam. Based on the studies, suggested size of gap and installation order were proposed. It is also confirmed that optimized concrete slab in mid-span can reduce the requirement of construction accuracy.

• Journal of the Korea Safety Management & Science
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• v.25 no.1
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• pp.15-21
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• 2023

In modern society, the delivery service market has grown explosively due to rapid changes in social structure and the recent COVID-19 pandemic. Therefore, various problems such as injury to workers and an increase in human accidents are occurring due to the loading and unloading of parcels. In order to solve this problem, domestic company n is developing a "robot-based cargo loading and unloading system". In developing a new technology system, quantitative reliability targets should be set for efficient operation and development. In this paper, reliability analysis was conducted through field data for the pneumatic gripper of the "robot-based cargo loading system". The reliability of the failure data was analyzed to estimate the distribution parameters and MTTF. Random data was derived for the probability of occurrence of a failure with the estimated value. By repeating the simulation to predict the number and year of failures according to the estimated parameters of the probability distribution, it was proposed as a method that reflects realistic probabilities rather than calculating with simple arithmetic using the average MTTF previously used in the field.

• Journal of the Korean Society for Library and Information Science
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• v.38 no.4
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• pp.67-83
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• 2004

The purpose of this study is to analyze the information service and the design of the information system of LG Science Land and NSDL which was designed as Integrated Information System in Science Digital Library for youth. After that, the requirement and inclination of the system user was analyzed through on-line questionnaire and finally the Subjective-Oriented Directory System was modified in detail as improvement issue of the system. This study has a significance in designing a user-friendly information environment that the youth can access information in science more conveniently and Proving the efficiency of it.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.4
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• pp.229-235
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• 2017

Until now, a study on a ubiquitous sensor network has been mainly concentrated in the areas of sensor nodes, and as a results, technologies related with sensor node were greatly developed. Despite of many achievements on research and development for a sensor node, a ubiquitous sensor network may failed to establish the actual service environment because variety of restrictions. In order to provide a actual service using a ubiquitous sensor networks applied to many results on research and development for a sensor nodes, a study on a wired/wireless composite router must be carried out. However a study on a wired/wireless composite router is relatively very slow compared with the sensor node. In this study, developed a high-performance router platform supporting IPv6 that can provide high-speed wired/wireless interface and QoS, and it can provide the multimedia service Interlocking the wireless sensor network and the Internet network. To analysis a given network environment and to develop the appropriate hardware and software in accordance with this requirement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.584-589
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• 2010

In this paper we suggest multimedia synchronization model that is based on the Petri-net and services desirable quality of service requirement. Proposed model applies variable buffer which can be allowed, and then it presents high quality of service and real time characteristics. In this paper we expend Petri-net and propose new multimedia synchronization specification model in PBMSM and apply two analysis method of Petri-net to prove our model suggested. We compared with other models and showed high QoS.

• Proceedings of the Korea Contents Association Conference
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• 2006.05a
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• pp.99-102
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• 2006

We recognize call centers as a interface frequently interacting with clients, and as the first portal of enterprises promoting customer satisfaction and increasing the rate of customer maintenance. The importance of service quality in call centers is gradually enlarged, as criteria for competitive power of enterprises, and the first-line interface of communications with customers in operating method and business management. Also, Enhancing service quality is the first task of both the management and telemarketers in order to adapt to the customer's requirement level. The curriculum for telemarketer education is not established or standardized within the country yet. We must therefore study on it as soon as possible, though it has a short history and insufficient theoretics. In this paper, we descirbe the development of a formal telemarketer education program in call centers included the result that analyze existing educational programs, and the opinion of call centers.

• The KIPS Transactions:PartA
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• v.16A no.3
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• pp.181-188
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• 2009

Transcoding is one of core techniques that implement VoD services according to QoS. But it consumes a lot of CPU resource. A transcoding proxy transcodes multimedia objects to meet requirements of various mobile devices and caches them to reuse later. In this paper, we propose a service policy that reduces the load of transcoding multimedia objects by degrading QoS in a transcoding proxy. Due to the tradeoff between QoS and the load of a proxy system, a transcoding proxy provides lower QoS than a client's requirement so that it can accomodate more clients.

• Proceedings of the Korea Information Assurance Society Conference
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• 2004.05a
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• pp.119-124
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• 2004

The service oriented architecture (SOA) is gaining more momentum with the advent of Web services on internet. A programmable and machine accessible Web is the vision of many, and might represent a step towards the semantic Web. However, security is a crucial requirement for the serious usage and adoption of the Web services technology. This paper proposes design goals for an distributed access control model for CPC(Collaborative Product Commerce). It then design a processor model for CPC components, along with web services standard and concept that can be used as a basis to design an access control processor independent of a particular CPC service implementation.

• Toxicological Research
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• v.22 no.1
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• pp.15-22
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• 2006

Many of endocrine disrupting chemicals induce effects via interaction with hormone receptors and responsive elements in target cells. We investigated endocrine disrupting effects of some food additives and contaminants including BHA, BHT, ethoxyquin, propionic acid, sorbic acid, benzoic acid, CPM, aflatoxin B1, cadmium chloride, genistein, TCDD and PCBs in yeast transformants expressing human steroid hormone receptors along with steroid responsive elements. The response limit of genetically recombinant yeast to $17{\beta}$-estradiol, testosterone and progesterone was $1{\times}10^{-16},\;1{\times}10^{-12}\;and\;1{\times}10^{-13}M$, respectively. BHT induced weak transcriptional activity in estrogen sensitive yeast, while BHA and sorbic acid interacted weakly with androgen receptor/responsive element. CPM induced transcriptional activities in all types of yeasts sensitive to steroid hormones. Zearalenone and genistein induced high transcriptional activation in estrogen sensitive yeast with relative potencies almost $10^8$ folds lower than $17{\beta}$-estradiol. TCDD induced transcriptional activation weakly in estrogen- and progesterone- sensitive yeasts. This study elucidated that recombinant yeast is a sensitive and high-throughput system and can be used for the direct assessment on chemical interactions with steroid receptors and responsive elements. Also, the present study raises the requirement of evaluation on the endocrine disrupting effects of BHT, BHA, sorbic acid, CPM and TCDD for their transcription activity in yeast screening system though weak in intensity.

• KIPS Transactions on Software and Data Engineering
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• v.6 no.3
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• pp.125-134
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• 2017

The SOA (Service Oriented Architecture) based softwares are escalated because of quickly coping with business requirement. SOA can not apply to existing test method because of loosely coupled service and massage exchange architecture. In this paper, we suggest a method of test case generation using BPMN (Business Process Model and Notation). First we model processes, then make Business Flow Graph (BFG). After searching the euler path through symmetrized BFG about input and output degrees, we generate test cases. A method of test case generation using BPMN can apply at SOA-based system, and reduce the number of test cases.