• 한국광물학회지
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• 제29권3호
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• pp.89-101
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• 2016

본 연구는 폐금속광산인 복수광산 주변토양을 대상으로 X선형광분석법, X선회절분석법 및 휴대용 분광계를 이용하여 토양 내 광물조성을 확인하고 비소, 납, 아연, 구리, 카드뮴 등의 중금속오염 정도에 따른 분광특성을 고찰하였다. 그 결과 대조군 시료를 제외한 모든 시료에서 토양오염대책기준을 초과하였다. X선회절분석 결과 모든 토양시료에서 석영, 고령토 그리고 스멕타이트 군의 광물이 검출되었고 중금속은 점토광물에 흡착하여 존재함을 확인하였다. 분광분석을 통해 대조군시료와 중금속 오염시료의 분광곡선을 분석한 결과 토양 내 중금속 함량이 증가함에 따라 근적외선대역과 단파적외선의 단파장 영역에서 반사도가 감소함을 확인하였다. 또한 흡광깊이에 따른 오염도와의 상관성을 고려하여 본 결과 점토광물의 흡광특성인 2312 nm와 2380 nm에서 점토광물에 의한 중금속흡착에 따라 오염도가 높을수록 흡광깊이가 감소하는 특징을 보인다. 이는 분광학적 특성이 중금속의 오염도와 상당한 상관성이 있음을 지시한다.

• 한국유통학회지:유통연구
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• 제15권5호
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• pp.127-153
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• 2010

본 연구는 지난 10년간 급격하게 변화하여 온 온라인 쇼핑산업에 대해 성장의 동력을 이론적으로 확인하고, 이들에 의한 이론적 설명을 시도한 탐색적 연구이다. 이러한 과정에서 이론적으로 선점이론에 대한 검토를 통해 이 이론이 유통구조에서 온라인 유통산업에서 발생하고 있는 재중간상화와 배치됨을 확인하였고, 이에 따라서 동적 역량이론을 활용한 온라인 산업에 대한 이론적 적용모델인 NEBIC에 대한 검토를 통해 동적성장이론인 이중나선구조 모형을 제안하였다. 또한 이론의 현실적합성을 확인하기 위해 2000년에서 2008년 한국 온라인 쇼핑산업의 발전과정을 재구성하고 각 기업의 매출자료 및 총매출액을 검토하여 현재 진행 중인 온라인 유통업의 동적 성장과정에서 각 기업의 역량이 시장에 적용되어지는 과정을 확인하고 새로운 진화방향을 제시하고자 하였다. 이러한 과정을 통해 보았을 때, 오픈마켓의 주도를 통한 시장 발전은 한계에 봉착한 것으로 보인다. 따라서 향후 온라인 쇼핑몰은 자기 기반 역량 위에서 유통경로 구조 전반에 걸친 유통기능의 개발과 상품개발을 통해 경로구조를 통합하는 방향으로 발전할 것으로 잠정적 결론을 내릴 수 있을 것이다. 이러한 결론에 기반하여 오픈마켓에서 육성된 대형 판매자들의 전문몰화, 상장기업화를 유도하는 한편, 상품취급범위를 제한하는 다양한 정책 및 규제를 통합운영하고 조정하는 컨트롤 타워의 구축, 그리고 오픈마켓의 중소 상인육성기능을 강화하기 위한 인센티브의 구성과 같은 정책적 제안이 제시되었다.

• 유통과학연구
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• 제13권6호
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• pp.97-104
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• 2015

Purpose - The distribution of agricultural products is changing due to recent shifts in environmental free trade. Specifically, the competitiveness of domestic agricultural products has weakened as a result of the Korea-China Financial Trade Agreement. Agricultural producers are faced with increasing difficulties and organized production centers are growing in importance daily. To overcome this crisis, agricultural producer organizations are vying for environment-friendly agricultural certifications, Good Agriculture Practices (GAP) and Hazard Analysis and Critical Control Point (HACCP). In particular, as consumer demand for higher safety grows, farmers are increasing their certification rates. Therefore, this certification system is expected to help strengthen the competitiveness of agricultural producer organizations. Research design/data/methodology - Organized production centers are classified by certification. A survey was conducted with 91 organizations using factor analysis and logistic regression analysis for the examination. The factor analysis results are as follows. Raw material procurement, education·specialization, marketing, joint business, organizing ability, business management, effectiveness, certification, and larger organizations were classified as the nine types of factors. These factors affect the organized production centers and are used in the logistic regression analysis. The purpose of such research and analysis is to suggest a direction for future production center policies. Results - The basic statistical results are as follows: analysis of the producer organizations of 91 sites, average number of members per site of 1,624, and average sales of 25,961 million won. Additionally, the average income per farmer is 175 million won, and the pooling system rate is 53.5%. The factor analysis results are as follows. Factor 1 consists of contract cultivation, ongoing shipment, selection subdivision, traceability, and major retailer management. Factor 2 consists of manual cultivation, specialty selection, education program, and R&D. Factor 3 consists of advertising, various dealers, various sales strategies, and a unified sales counter. Factor 4 consists of agricultural materials co-purchase, policy support, co-shipment, and incentives. Factor 5 consists of the co-selection and pooling system. Factor 6 consists of co-branding and operating by the organization's article. Factor 7 consists of the buy-sell ratio and rate of operation of the agriculture promotion center. Factor 8 consists of bargaining power in volume and participation rate of farmer certification. Factor 9 consists of increasing new subscribers. The logistic regression analysis results are as follows. Considering the results by type of certification, the environment-friendly agricultural certification type and the GAP certification type have a (+) influence. GAP and HACCP certification types affecting the education·specialization factor have a (+) influence. Considering the results for each type of certification, the environment-friendly agricultural certification types on the effectiveness factor have (-) influence; the HACCP certification types on the organizing ability and effectiveness factor have a (-) influence. Conclusions - Agricultural producer organizations should develop plans as follows: The organizations need to secure education for agricultural production; increase the pooling system ratio for sustainable organizational development; and, finally, expand the number of agricultural producer organizations.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 춘계 학술대회
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• pp.101-109
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• 2005

본 논문에서는 불필요한 용액의 발생이 없이 전해 반응계로 주입되는 용액을 오직 pH 만을 조절시켜 배출시키기 위한 연속식 이온 교환막 전해 시스템을 개발하였다. 여기서는 전해 반응기 앞에 한 pH-조정조를 두고 대상 용액을 pH-조정조로 주입하면서 pH-조정조의 용액의 일부를 이온 교환막에 따라 음극방 또는 양극방으로 거처 다시 pH-조정조로 순환하게 하고. 또한 pH-조정조의 용액의 일부는 상대극방을 통과시킴으로써 pH가 산성 또는 알카리로 조절되어 배출되게 하였다. 이러한 전해반응기에서 pH 조절 과정은 음극과 양극 사이에 전압 차가 형성될 시, 이온 교환막을 통한 용액에 존재하는 이온의 전기이동 현상에 의해 유발되는 음극방과 양극방에서 용액의 전하 비 평형 현상과 이에 따른 물의 전해 분해 과정에 의해 설명되었다.

• 보건교육건강증진학회지
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• 제23권1호
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• pp.63-75
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• 2006

Objective: This study was performed to identify the related factors of change affecting the stage of change, on the assumption that there are various stages of change in the exercise behavior of workers. Method: The subjects of the study consisted of 138 workers of 10 workplaces located in Daejeon City, and data collected by using questionnaires were analyzed with SPSS/WIN 11.5 program. Results: The subjects were distributed in the stage of exercise behavior change as follows: precontemplation stage(10.9%), contemplation stage(22.5%), preparation stage(41.3%), action stage(8.7%), and maintenance stage(16.7%). Of the process of change depending on the stage of exercise behavior change, the consciousness raising(F=11.50, p=.00), dramatic relief(F=2.82, p=.02) showed significant difference in the cognitive process, and the counter conditioning(F=4.56, p=.00), reinforcement management(F=4.64, p=.00), self-liberation(F=9.46, p=.00), and stimulus control(F=13.28, p=.00) showed significant difference in the behavioral process. For decision-making depending on the stage of exercise behavior change, both the pros of decision-making(F=9.23, p=.00) and the cons of decision-making(F=2.45, p=.04) showed significant difference. Self-efficacy depending on the stage of exercise behavior change showed significant difference as F=11.50, p=.00. The related factors of change affecting the stage of exercise behavior change were the pros of decision-making, the cons of decision-making, and self-efficacy including 34.1% R-square. Conclusion: In order to change the exercise behavior of workers positively, they need to be stimulated to use the cognitive and behavioral process in the process of change properly, and to be induced to make a decision positively. And also exercise programs suitable to various characteristics of each worker as well as those of workplaces to enhance self-efficacy need to be applied after being devised. Through the further longitudinal research, it is necessary to analyze the various aspects, such as groups to select, to maintain, to stop or give up the exercise, and to avoid the change, and to study how the related factors of change affect diversity like the above.

• Journal of Periodontal and Implant Science
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• 제24권1호
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• pp.144-154
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• 1994

Final goal of periodontal treatment is to reconstruct the destructed periodontal tissue as well as to remove the necrotic pathologic elements. The purpose of this study is to investigate on the effect of Zizyphi extract to the inhibitory ability on collagenolytic activity of P gingivalis, biologic activity of gingival fibroblasts, and on the collagen and protein synthesis of gingival fibroblasts. Gingival fibroblast from giniva of first bicuspids from patient for orthodontic treatment were used and cultured. For the measurement of inhibitory ability of collagenolytic activity, crude enzyme was extracted and used on the basis of modified Ono's method. On the inhibition of collagenolytic enzyme from herbal extracts, collagenokit CLN-100 were used. The cellular activity of gingival fibroblast, were studied using MTT solution and measured optical density on 570mm by ELISA reader. To measure the effects on the ability of whole protein and collagen synthesis, cell membrane was destructed with ultrasonic grinder after culturing, centrifuged and counted by liquid scintilation counter. The inhibitory effects on producing of $IL-l{\beta}$ by monocyte, after promotion of producing $IL-l{\beta}$ by LPS, were compared with the mixture of herbal extracts and other drugs using thymocyte stimulation assay. About inhibitory effects of $PGF_2$. by gingival fibroblasts, herbal extract was compared with the addition of the other control groups using enzyme imunoassay. On the inhibition of collagenolytic activity by P. gingivalis, benzene extracts showed the most efficient inhibitory effects among the $19{\mu}g/ml$ of the compared extracts and 40.5% by Tetracycline. On the cellular activity promoting effects, compared extracts showed a bit of more effects than PDGF of $100{\mu}g/ml$ concentration and IGF of $20{\mu}g/ml$ concentration. All of the PDGF, IGF, Zizyphi Fructus extract should increase in collagen synthesis, but especially 70% ethylalcohol extracts of Zizyphi Fructus showed comparably high effects among the compared extracts. Effects on whole protein synthesis were slightly increased on every extract but especially 70% ethylalcohol extract showed significantly effective than any other estract. On the inhibitory effects of Zizyphi Fructus $IL-l{\beta}$ production by monocyte, compared extracts showed 70% of highly inhibitory effect than that of 60% inhibition effects on controlled group and each extracts showed no significant difference. In $PGF_2$ production inhibitroy effect of Zizyphi Fructus gingival fibroblasts, Herbal extracts showed 70% of inhibition comparing with tat of 90.2% of controlled group, but each extracts showed similar effects excluding the $H_2O$ extracts. These results suggested that Zizyphi Fructus might be useful medicine for inhibition of inflammatory mediator including $IL-l{\beta}$ and $PGF_2$.

• 한국통신학회논문지
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• 제28권11C호
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• pp.1077-1087
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• 2003

본 논문에서는 IPsec등의 네트워크 보안 프로토콜을 위해 다중모드를 가지는 블록암호시스템의 구조를 제안하고 ASIC 라이브러리를 이용해서 하드웨어로 구현하였다. 블록 암호시스템의 구성을 위해서 AES, SEED, 그리고 3DES 등의 국내외 표준 블록암호화 알고리즘을 사용하였고 네트워크를 비롯한 유/무선으로 입력되는 데이터를 최소의 대기시간(최소 64클럭, 최대 256클럭)만을 가지면서 실시간으로 데이터를 암호화 혹은 복호화시킬 수 있다. 본 설계는 ECB, CBC, OFB뿐 아니라 최근 많이 사용되는 CTR(Counter) 모드를 지원하고 다중 비트단위(64, 128, 192, 256 비트)의 암/복호화를 수행한다. IPsec등의 네트워크 보안 프로토콜로의 연계를 위해 알고리즘 확장성을 보유한 하드웨어로 구현되었고 여러 암호화 알고리즘의 동시적인 동작이 가능하다. 적절한 하드웨어 공유와 프로그래머블한 특성이 강한 내부데이터 패스를 통해 자체적인 블럭암호화 모드를 지원하기 때문에 다양한 방식의 암/복호화가 가능하다. 전체적인 동작은 직렬 통신에 의해서 프로그래밍되고 명령어의 디코딩을 통해 생성된 제어신호가 동작을 결정한다. VHDL을 이용해 설계된 하드웨어는 Hynix 0.25$\mu\textrm{m}$ CMOS 공정을 통해 합성되었고 약 10만 게이트의 자원을 사용하였으며, 100MHz 이상의 클럭 주파수에서 안정적으로 동작함을 NC-Verilog에서 확인하였다.

• 기본간호학회지
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• 제2권1호
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• pp.87-101
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• 1995

This study was conducted with the subject of showing the importance of early rehabilitation and exercise therapy in patients who have stroke, of confirming the adavntage of ward exercise conducted by nurse, which had been conducted mainly by physical therapist only in physical thrapy room and of developing the exercise program as the independent rehabilitation nursing intervention. A total of 62 patients were selected as object from April, 5th, to May, 17th, 1995, who had been hospitalized in K medical center, and the half of them were assigned to Experimental group in ramdom assignment using a coin. It was ADL check list tool developed by Kang and Ward Exercise Program developed by the researcher that were used as a treatment. Ward Exercise Program was conducted by the reseacher and the physical therapist measured ADL score before and after Ward Exercise Program. The data were analyzed using ANOVA, pearson correlation, Chi-Square test and the effect of Ward Exercise Program was analyzed by t-tast. The result of this study is as follows. 1. The experimental group showed eminent improvement of ADL compared with the counter group with statistical significance. In eating(t=6.10, df=60, p=.000), personal hygiene performing(t=4.86, df=60, p=.000), wearing(t=5.86, df=60, p=.000), elimination(t=7.89, df=60, p=.000), mobility on the bed(t=13.36, df=60, p=.000), moving(t=9.11, df=60, p=.000), walking(t=7.45, df=60, p=.000) 2. There was no qualitative difference between experimental group and control group with the significance of $p{\le}.05$. 3. There was no relation between the general condition and the difference of ADL, while there was significant relation between the starting point of exercise and the difference of pre-exercise and post exercise ADL. As a result, it should be emphasized that the early rehabilitation and exercise therapy are important in patients who have stroke, and that it is necessary to extend the exercise therapy to the ward. Therefore, this Ward Exercise Program could be recommended as a independent clinical exercise nursing intervention in rehabilitation nursing of patients who have stroke.

• 한국태양에너지학회 논문집
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• 제28권2호
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• pp.64-69
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• 2008

As the grid-connected photovoltaic power conditioning systems (PVPCS) are installed in many residential areas, these have raised potential problems of network protection on electrical power system. One of the numerous problems is an Islanding phenomenon. There has been an argument that it may be a non-issue in practice because the probability of islanding is extremely low. However, there are three counter-arguments: First, the low probability of islanding is based on the assumption of 100% power matching between the PVPCS and the islanded local loads. In fact, an islanding can be easily formed even without 100% power matching (the power mismatch could be up to 30% if only traditional protections are used, e.g. under/over voltage/frequency). The 30% power-mismatch condition will drastically increase the islanding probability. Second, even with a larger power mismatch, the time for voltage or frequency to deviate sufficiently to cause a trip, plus the time required to execute a trip (particularly if conventional switchgear is required to operate), can easily be greater than the typical re-close time on the distribution circuit. Third, the low-probability argument is based on the study of PVPCS. Especially, if the output power of PVPCS equals to power consumption of local loads, it is very difficult for the PVPCS to sustain the voltage and frequency in an islanding. Unintentional islanding of PVPCS may result in power-quality issues, interference to grid-protection devices, equipment damage, and even personnel safety hazards. Therefore the verification of anti-islanding performance is strongly needed. In this paper, improved RPV method is proposed through considering power quality and anti-islanding capacity of grid-connected single-phase PVPCS in IEEE Std 1547 ("Standard for Interconnecting Distributed Resources to Electric Power Systems"). And the simulation results are verified.

• 한국정보과학회논문지:정보통신
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• 제29권4호
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• pp.447-458
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• 2002

본 연구에서는 무선 인터넷 서비스를 위한 전송계층 프로토콜인 TCP, T/TCP와 WTP의 특징을 비교.분석한다. 우선 무선구간에 가장 적합한 WTP를 제한된 자원을 가진 무선 단말기상에 탑재하기 용이하도록 코루틴 모델을 기반으로 하나의 쓰레드로 구현하고 이를 Nokia, Kannel 그리고, WinWAP 의 기존 구현물과 상호 동작시켜 호환성을 검사한다. 그리고, 무선환경에서의 패킷손실을 잘 표현할 수 있는 길버트(Gilbert) 모델을 기반으로 구현물의 트랜잭션 성공률(throughput) 및 수행시간(system response time)을 측정하여 기존의 TCP, T/TCP와 비교한다. 그 결과, WTP는 트랜잭션 성공률과 수행 시간에 있어서 기존의 프로토콜에 비해 높은 성능을 보였다. 특히, 연속적인 에러가 발생하며 패킷손실률이 비교적 높을 때, WTP는 T/TCP와 TCP에 비해 매우 높은 트랜잭션 성공률을 나타냈으며, 10배 이상 빠른 수행 시간을 보였다. 이는 WTP가 다른 프로토콜에 비해 적은 개수의 패킷으로 하나의 트랜잭션을 수행하고 패킷 손실로 인한 타임아웃 발생 시, 타이머 값을 exponential backoff를 적용하지 않고 일정한 값을 유지하기 때문이다. 또한, 무선환경에 최적화된 WTP의 재전송 횟수를 결정하기 위한 실험을 통해, 가장 적절한 재전송 횟수가 5~6회임을 알 수 있었다.