• 해양환경안전학회지
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• 제17권2호
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• pp.161-166
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• 2011

본 연구에서는 태양전지로 구동되는 전기추진 소형선박을 제안하여 선체의 설계 및 모형선 시험을 행하였다. 선체 모양은 배의 안정성 및 태양과의 수광면적을 고려하여 차타마란형으로 제작하였다. 계산에 의하면 설계 선박의 선속을 5 knots로 할 때 1.1마력으로 충분한 추력이 산출되었으나 실제의 선속은 태양에너지 등 기후조건에 의해 산출된 값보다 약간 낮았다.

• The International Journal of Costume Culture
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• 제2권1호
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• pp.62-76
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• 1999

The objectives of this study are to investigate consumer experiences with premiums, consumer preferences in premiums offered for clothing and the effect of premiums on clothing purchasing behaviors. A self-administered questionnaire survey was conducted to 610 men and women from ages 15 to 59 living in the Seoul metropolitan area from February 25 to March 9, 1999 ; 548 were used for the data analysis. Data was analyzed by descriptive statistics, t-test, ANOVA, chi-square analysis and Duncan's multiple range tests. Significant differences were found among selected demographic groups in information sources used for premium offers, experiences of receiving premiums, purchasing experiences due to premium offers, preferences between discount and premiums, additional purchase intentions because of premiums, and the premiums'influences. The groups with purchase experiences or brand and stores selecting experiences due to premium, showed significant differences in premiums'influences and the satisfaction levels with premiums. Regarding preferences between discount and premiums, significant differences were found in and the satisfaction levels with premiums.

• 상하수도학회지
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• 제30권5호
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• pp.533-543
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• 2016

Supplying clean and safe water to people is facing both quantitative and qualitative challenges. Due to climate change, access to freshwater becomes increasingly difficult, while pollution from various sources decreases the public trust in water quality. Managed aquifer recharge (MAR) which stores and uses surface water in aquifer is receiving attention as a new technology to secure freshwater. Recently, there is a global expansion in the attempt to combine general purification plants and hazard analysis and critical control point (HACCP) which manages all the process from raw material to consumer for food safety. This research is about an attempt to apply HACCP to the drinking water supply process using MAR to secure both quantity and quality of drinking water. The study site is a MAR plant being constructed in the downstream area of the Nakdong River Basin, South Korea. The incorporation of HACCP with MAR-based water supply system is expected to enhance the safety and reliability of drinking water.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.33-34
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• 2006

Computer Forensics is a research area which finds the malicious users by collecting and analyzing the intrusion or infringement evidence of the computer crime. Many research about Computer Forensics has been done. But those research have focussed on how to collect the evidence after receiving the damage reports from computer users or network administrators. This paper describes about collecting the evidence of good quality at the time of infringement occurrence by the malicious user. By calculating Infringement severity of observable and protective hosts and referring to this value, we collect the evidence at the time of infringement occurrence to minimize the information modification of the evidence. We can reduce also the amount of logs that we use to analyze the infringement and can minimize the loss of the evidence.

• 한국전자파학회논문지
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• 제10권3호
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• pp.430-439
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• 1999

본 논문에서는 인천국제공항을 프랏터 (flutter) 장애 예측 대상지역으로 선정하여 프랏터 장애를 예측.분석하였으며, 이에 대한 대책 방안을 제시하였다. 프랏터 장애.예측 함수로서 직접파 전계강도, 안테나 높이, 송신점 ERP, 반사계수 등을 고려하여 프랏터 장애에 대해 컴퓨터 시뮬레이션을 수행하였다. 결과로부터, 항공기 운항에 따른 프랏터 장애는 매우 심각한 것으로 나타났고 항공기와 전파공신점과의 거리, 전파 송신점과 수신점간의 지형 및 항공기의 반사계수에 따라 프랏터의 장애 정도가 달라짐을 알 수 있었다.

• Journal of Communications and Networks
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• 제13권2호
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• pp.160-166
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• 2011

In u-healthcare services based on wireless body sensor networks, reliable connection is very important as many types of information, including vital signals, are transmitted through the networks. The transmit power requirements are very stringent in the case of in-body networks for implant communication. Furthermore, the wireless link in an in-body environment has a high degree of path loss (e.g., the path loss exponent is around 6.2 for deep tissue). Because of such inherently bad settings of the communication nodes, a multi-hop network topology is preferred in order to meet the transmit power requirements and to increase the battery lifetime of sensor nodes. This will ensure that the live body of a patient receiving the healthcare service has a reduced level of specific absorption ratio (SAR) when exposed to long-lasting radiation. We propose an efficientmethod for delivering delay-intolerant data packets over multiple hops. We consider forward error correction (FEC) in an erasure correction mode and develop a mathematical formulation for packet-level scheduling of delay-intolerant FEC packets over multiple hops. The proposed method can be used as a simple guideline for applications to setting up a topology for a medical body sensor network of each individual patient, which is connected to a remote server for u-healthcare service applications.

• ETRI Journal
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• 제40권1호
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• pp.26-38
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• 2018

To overcome considerable path loss in millimeter-wave propagation, high-gain directional beamforming is considered to be a key enabling technology for outdoor 5G mobile networks. Associated with beamforming, this paper investigates propagation power loss characteristics in two aspects. The first is beamwidth effects. Owing to the multipath receiving nature of mobile environments, it is expected that a narrower beamwidth antenna will capture fewer multipath signals, while increasing directivity gain. If we normalize the directivity gain, this narrow-beamwidth reception incurs an additional power loss compared to omnidirectional-antenna power reception. With measurement data collected in an urban area at 28 GHz and 38 GHz, we illustrate the amount of these additional propagation losses as a function of the half-power beamwidth. Secondly, we investigate power losses due to steering beam misalignment, as well as the measurement data. The results show that a small angle misalignment can cause a large power loss. Considering that most standard documents provide omnidirectional antenna path loss characteristics, these results are expected to contribute to mmWave mobile system designs.

• 한국빅데이터학회지
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• 제1권1호
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• pp.1-7
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• 2016

인터넷의 확산으로 트위터와 같은 SNS가 확산되었고, 컴퓨터 처리 능력의 발달로 빅 데이터 처리가 가능해졌다. 본 연구에서는 현재 주목 받고 있는 기술인 스마트 워치에 대해 다루고 있으며 최근 출시되었던 삼성 갤럭시 기어 S2를 대상으로 연구를 진행하고 있다. 스마트 워치의 출시 전, 후에 게시되었던 트위터 데이터를 수집하여 실제 SNS 사용자들이 신제품 출시에 어떻게 반응하고 있으며 어떠한 다른 양상을 보이는지 분석한다. 분석을 통해 기업 실무자들에게 출시 전, 출시 후 각각에 마케팅에 대응하는 방법에 관한 가이드라인을 제공하며 본 연구에서 사용된 분석 프레임워크는 다른 분야 및 제품에서도 사용 가능한 연구 가이드라인이 된다.

• 기본간호학회지
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• 제16권1호
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• pp.92-102
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• 2009

Purpose: Relocation stress is a common phenomenon in patients discharged from an intensive care unit(ICU) to a ward. Therefore, nurses need to be aware of the problems that can arise during the transfer process. The aim of this study was to identify nurses' experiences in transferring critically ill patients from the ICU to a ward. Method: Focus group interviews were done with 13 nurses from wards and ICU, which participated in receiving and sending of ICU patients. The debriefing notes and field notes were analyzed using the consistent comparative data analysis method. Result: Seven major categories were identified in the analysis of the data. These were 'mixed feeling about transfer', 'lack of transfer readiness', 'increase in family burden', 'uncertainty with unfamiliar environment', 'difficulty in decision making', 'difference of perception of the relationships between patients and health care providers', 'need for continuity of nursing care'. Conclusion: Transferring out of the critical care area should be presented to the patient and family as a positive step in the recovery process. However, a more universal method of passing information from nurse to nurse is needed to assist in a smooth transition.

• 대한안전경영과학회지
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• 제9권4호
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• pp.99-112
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• 2007

In most recent years, the business competition has spreads over all fields of corporations and their management area regardless of time and place, which makes the survival environment of each enterprise fiercer. In order to secure a high position in the competitive market, the various firms has implemented many methods related to price, quality, and service efficiency. However, the implementation with only low price or high quality might be helpless to hold a high position in modem market. Moreover more attention should be paid to the internal business processes of an organization. Therefore, a new and different method should be searched or developed in order to win the competitive power among other enterprises. This research will focus on the improvement of the business processes within the non-manufacturing industry by applying Lean Six Sigma methodology. DMAIC method will be applied to improve the inbound and outbound logistics processes, manage the inbound and outbound vehicles, and control the receiving and shipping activities.