• Journal of the Institute of Electronics Engineers of Korea SC
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• v.41 no.1
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• pp.41-54
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• 2004

In this paper, we propose a new digital hearing aid circuit that compensates the impaired threshold level changing nonlinearly using a multi-band compensation technique. In the algorithm the hearing frequency range 8kHz is divided into 64 bands which is 125Hz resolution. Each band is controlled finely to compensate the hearing impaired proportional to personal ROM table. The multi-band is introduced using a FFT/IFFT Processor which makes to control in frequency domain. As a result, the proposed circuit is more efficient $15\%$ than a conventional ones such as FIR filter architecture in terms of the compensation gun and accuracy. The hardware size was reduced $65\%$ than a general FFT by pre-handling of the input data.

• Journal of the Korean Geosynthetics Society
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• v.14 no.3
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• pp.13-20
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• 2015

Inappropriate backfill material and poor compaction cause the damage to sewer and ground settlement. To deal with such problem, flowable backfill material has attracted attention recently. A basic study was conducted in a bid to obtain optimum mixing ratio of backfill material with the characteristics of rapid hardening, pseudo-plasticity, flowability and anti washout ability and enhance the cost efficiency of backfill material. Through the test of optimal mixing ratio of rapid hardening, evaluation of optimal mixing ratio of backfill material was conducted. As a result, required performance as well as cost efficiency could be achieved by adjusting plasticizer even in case of increasing W/M of the paste of rapid hardening to 100%.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.1
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• pp.161-171
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• 1993

The aim of this study is to provide the stress-strain behavior of hardening geological materials such as rock or concrete on three dimensional spaces by using Desai model based on plastic theory. To validate proposed model, truly triaxial tests with high pressure under variety of stress paths in which three principal stresses were controlled independently using concrete materials were performed. The main results are summerized as follows: 1. Various stress paths for hardening materials used are satisfactorily explained by performing the truly triaxial test with high pressure. This is very important to investigate constitutive equations for materials like rock or concrete. 2. Since the proposed yield function is continuous, it avoids the singularity point at the intersection of two function in the previous models, thus, reducing the difficulties for computer implementation. 3. Analytic predictions for yielding behavior on $J_1-{\sqrt{J_{2D}}}$ octahedral and triaxial plane, as well as volumetric strain and stress-strain behavior agree well with experimental results.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.72-72
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• 2012

본 연구에서는 친환경 리싸이클 섬유산업의 활성화를 위해 대학생들의 리싸이클 폴리에스터 섬유에 대한 인식도를 분석해 보고자 하였다. 측정 문항은 섬유전문가 3인의 검토를 거쳐 타당성을 확보하였으며, 조사는 질문지법으로 2011년 9월 1일부터 9월 10일까지 대전 거주 대학생을 대상으로 진행하였으며, 회수된 설문지 196부를 자료 분석에 이용하였고, SPSS 19 통계 패키지를 이용하여 자료를 통계분석하였다. 연구 결과는 다음과 같다. 1. 친환경적 의생활 실태 조사를 실시한 결과, 리싸이클 PET섬유에 대해 들어본 적이 있는 사람은 조사대상자의 27.6%로 나타났고, 그 정보원으로는 인터넷을 가장 많이 이용하는 것으로 나타났다. 2. 섬유소재별 친환경성에 대한 인식도를 조사한 결과, 대학생들은 리싸이클 PET섬유가 천연섬유보다 덜 친환경적이나, 인조섬유보다는 더 친환경적이라고 인식하는 것으로 나타났다. 3. 리싸이클 PET섬유에 대한 인식도를 요인분석한 결과, <친환경성 요인>, <촉감 요인>, <내구성 요인>, <기능성 요인>, <공정 요인>, <글로벌 경쟁력 요인>및 <부가가치성 요인> 등 7개의 요인이 도출되었는데 이는 대학생들은 리싸이클 PET섬유에 대해 친환경성, 촉감, 내구성, 기능성, 공정, 글로벌경쟁력, 부가가치성순으로 중요하게 인식하는 것으로 해석된다.

• Journal of Environmental Policy
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• v.6 no.4
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• pp.83-101
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• 2007

We try to analyze the relationship between environmental and financial performance in the Korean manufacturing sector. The lack of reliable information on company-level environmental performance in Korea has inhibited research on this subject. This paper utilizes an objective data set called 'Monthly Environmental Violations Report,' published by the Korean Ministry of Environment, among others, in measuring the environmental performance of the listed companies. The result shows that low polluters tend to perform better financially than high polluters. In addition, the correlation between positive environmental performance and financial performance turns out to be statistically more significant than negative environmental and financial performance.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.9
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• pp.684-690
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• 2006

This paper proposes a message transmission model for hard real-time communications of periodic messages on a switched Ethernet and also proposes an algorithm to schedule the messages to be transmitted within their deadlines. The proposed scheduling algorithm is a distributed one and is peformed by the source and the destination nodes without the modification of the operational features of the standard Ethernet switch. When a new periodic message needs to be transmitted, it is first checked whether it can be scheduled on both the transmission and the reception links without affecting the already-scheduled messages, and a feasible schedule is made for the new message if it is schedulable. The proposed scheduling algorithm guarantees the transmission of periodic messages within their deadline and allows flexible message transmission on a hard real-time switched Ethernet through the dynamic addition of new periodic messages during run-time.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.567-579
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• 2013

The purpose of this paper is illuminating positively the perception and compliance rate of local food principles in Korea. The results are as follows. First, in terms of the perception rate, social trust and local production/consumption are the most important components rather than eco-friendliness. This means the importance of both spatial and social aspects of local food concept. Second, in terms of the compliance rate, social trust and shortened food chain are well complied, rather than eco-friendliness and shortened food miles. Third, in terms of the difference between perception and compliance rate, the social aspects such as eco-friendliness, social trust, and shortened food chain has shown relatively smaller difference than the spatial aspects such as shortened food miles and local production/consumption.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.2
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• pp.135-141
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• 2013

In this study, to improve the early-age compressive strength of mortar, the compressive strength tests of mortar mixed smart BFS powder added powder of rapid setting additives milled by processing, using functional grinding aid, the power-typed rapid setting cement clinker developed by sintering industrial waste and by-products with much CaO-$SiO_2-Al_2O_3$ to cement were performed. From the tests, the followings are found that (1) for BFS early-age strength improvement test (Series I): early-age strength improvement of BFS mixed rapid setting additive milled after adding functional grinding aid, when the clinker is milled, is superior and (2) for OPC early-age strength improvement test (Series II): case of additive mixed rapid setting powder typed activator milled after adding functional grinding aid to Clinker-C showed the higher compressive strength.

• Journal of vocational education research
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• v.30 no.4
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• pp.143-159
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• 2011

The purpose of this study is to develop and validate Inventory of Peer Relation for middle and high school students. First of all, in Study 1, 113 preliminary test questions were developed after reviewing of precedent studies in order to develop the Inventory of Peer Relation for Middle and High School Students. In Study 2, for the factor analysis, the survey was conducted for 600 students in three middle schools and three high schools in Busan to develop a final test, and finally 42 questions of them were selected. In Study 3, correlation analysis with another two inventories of peer relation was conducted to validate the developed Inventory of Peer Relation. The Inventory of Peer Relation developed through this study can be said reliable and valid. We made some suggestions for future studies.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1263-1268
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• 2018

In this paper, a video analysis is proposed to implement video surveillance system with deep learning object detection and probabilistic data association filter for tracking multiple objects, and suggests its implementation using GPU. The proposed video analysis technique involves object detection and object tracking sequentially. The deep learning network architecture uses ResNet for object detection and applies probabilistic data association filter for multiple objects tracking. The proposed video analysis technique can be used to detect intruders illegally trespassing any restricted area or to count the number of people entering a specified area. As a results of simulations and experiments, 48 channels of videos can be analyzed at a speed of about 27 fps and real-time video analysis is possible through RTSP protocol.