• 한국통신학회논문지
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• 제30권8A호
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• pp.656-663
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• 2005

본 논문에서는 IEEE 802.15.3 High-Rate WPAN (Wireless Personal Area Network) 환경에서 다중 채널을 사용하여 향상된 성능의 MAC 프로토콜을 제안한다. IEEE 802.15.3 High-Rate WPAN은 10m 내외의 거리에서 실시간 비디오 및 대용량 파일 전송을 목적으로 설계된 MAC과 PHY의 표준을 말한다. 현재 표준의 MAC 프로토콜은 하나의 무선 채널을 piconet 내의 모든 DEV가 공유하여 사용한다. 이 중 PNC(Piconet Coordinator)는 TDMA(Time Division Multiple Access)방식으로 DEV들에게 채널타임을 할당한다. 이런 경우 piconet내의 통신하는 DEV의 수가 많아지게 되면 superframe의 길이가 길어져 전송되는 데이터의 aggregate throughput이 떨어지고 QoS(Quality of Service)를 보장하지 못한다. 본 논문에서 하나의 piconet이 여러 개의 채널을 동시에 사용하여 aggregate throughput을 향상시키고 QoS를 보장하는 다중채널 MAC 프로토콜을 제안하고 시뮬레이션을 통해 향상된 성능을 증명한다.

• Journal of Communications and Networks
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• 제11권1호
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• pp.26-35
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• 2009

In this paper, we investigate how to do resource allocation to guarantee a minimum user data rate at low signaling overhead in multi-cell orthogonal frequency division multiple access (OFDMA) wireless systems. We devise dynamic resource allocation (DRA) algorithms that can minimize the QoS violation ratio (i.e., the ratio of the number of users who fail to get the requested data rate to the total number of users in the overall network). We assume an OFDMA system that allows dynamic control of frequency reuse factor (FRF) of each sub-carrier. The proposed DRA algorithms determine the FRFs of the sub-carriers and allocate them to the users adaptively based on inter-cell interference and load distribution. In order to reduce the signaling overhead, we adopt a hierarchical resource allocation architecture which divides the resource allocation decision into the inter-cell coordinator (ICC) and the base station (BS) levels. We limit the information available at the ICC only to the load of each cell, that is, the total number of sub-carriers required for supporting the data rate requirement of all the users. We then present the DRA with limited coordination (DRA-LC) algorithm where the ICC performs load-adaptive inter-cell resource allocation with the limited information while the BS performs intra-cell resource allocation with full information about its own cell. For performance comparison, we design a centralized algorithm called DRA with full coordination (DRA-FC). Simulation results reveal that the DRA-LC algorithm can perform close to the DRA-FC algorithm at very low signaling overhead. In addition, it turns out to improve the QoS performance of the cell-boundary users, and achieve a better fairness among neighboring cells under non-uniform load distribution.

• 임상간호연구
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• 제14권3호
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• pp.99-115
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• 2008

Purpose: The purpose for this study was to identify the present state of Clinical Nurses with Expanded Role (CNERs) and provide basic data to refine the roles of CNERs. In this study, CNREs refers to nurses who perform techniques traditionally done by doctors and use titles such as clinical nursing specialist, educator with consultation, research assistant, coordinator, physician assistant and special examiner. Method: This study was conducted from September 1 to November 12, 2007. Data from 684 nurses from 38 hospitals who responded to the questionnaire were analyzed with descriptive statistics using the SPSS 14.0 program. Results: The mean percentage of time spent was, for direct practice, 41.1%, for education and counseling, 22.8%, for consultation and coordination, 10.4%, for research, 6.8%, for administration, 8.9% and for other activities, 10.0%. The most frequently implemented CNERs, activities included consultation and education for patients and their families, counseling by telephone, history taking, physical examination, reading examination results, psychosocial assessment, managing treatment, input of prescriptions, and writing up patient records, Although not frequently performed, nurses in some fields carried out invasive procedures and prescribed medication and laboratory tests. Conclusion: Although the number of hospital CNERs are rapidly increasing, there is still confusion about the title and framework as well as standards. Furthermore, because some nurses are prescribing medication and laboratory tests as well as performing techniques not traditionally done by nurses, there is an absolute need for a legalized system and systematic education system for the safety of patients who are being cared by all CNERs.

• 한국간호교육학회지
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• 제21권4호
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• pp.528-539
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• 2015

Purpose: The purpose of this study was to develop an integrated nursing practicum education matrix based on the learning outcomes of each stage. Methods: In this Delphi technique study, 10 experts, consisting of six professors and four nurses, participated in the development of the matrix. The first step was an in-depth review for the composition of the questionnaire and the second step was the Delphi technique. The Delphi survey was conducted two times in order to complete the components of the matrix. The survey data was analyzed for statistical averages and standard deviations to decide the order of priority. Results: According to each stage (i.e. fundamental stage, competent stage, and proficient stage), the matrix was composed of education contents, methods, evaluation methods, and curriculum outcomes. Conclusion: The integrated nursing practicum education matrix of Y University was completed. The developed matrix will result in a reduction in the gap between nursing education and clinical practice and an improvement in nursing competency.

• 한국통신학회논문지
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• 제30권11B호
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• pp.792-803
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• 2005

초광대역 무선통신 (UWB) 기술은 그 자체가 가지고 있는 고속, 저전력, 다중 경로 환경의 강인함 등의 특성으로 고속형 WPAN에 적합한 기술로 평가받고 있다. 본 논문에서는 UWB 기술을 사용하는 WPAN 환경에서 전력 소비를 효율적으로 분산시킬 수 있는 MAC 계층에서의 다중 홉 프레임 중계 방식을 새롭게 제안한다. 본 논문에서는 적절한 중계 단말을 선택하기 위해 PAPSF (Power Aware Path Status Factor)를 정의한다. PAPSF는 SINR과 각 단말에서의 송신 전력 정보로부터 결정 할 수 있다. 본 논문에서 제안하는 방법은 에드 혹 라우팅 프로토콜의 특성으로 인하여 쉽게 중계 단말로 사용될 가능성이 높은 PNC를 통한 프레임 중계 방식과 비교할 때 더 높은 데이터 처리량을 가지며, 전체 전력 소모를 감소시킬 수 있다. 또한 전력 소모를 PNC 뿐만 아니라 피코넷에 존재하는 다른 단말들로 쉽게 분산시킬 수 있어 PNC의 급격한 배터리 소모를 방지하고, 빈번한 PNC 변경을 막을 수 있다.

• 한국통신학회논문지
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• 제34권3B호
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• pp.264-273
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• 2009

본 논문에서는 IEEE 802.15.3 HR-WPAN(High Rate Wireless Personal Area Network)의 PNC(PincoNet Coordinator)에서 DEV(DEVice)의 링크 상태에 따라 동적으로 채널 시간을 할당하는 DABL(Dynamic Allocation of channel times Based on Link quality of the DEV) 알고리즘을 이용하여 시스템에서의 평균 트래픽 전송률을 향상시키고 지연시간을 감소시키는 방법을 제안한다. 좀 더 구체적으로, DABL 알고리즘은 DEV의 링크 상태에 따라 다중 변조 기법을 제공할 뿐만 아니라, 슈퍼프레임에서의 각 DEV를 위한 채널 타임도 동적으로 스케줄링하는 방법을 제공한다. 또한 트래픽의 QoS(Quality of Services)를 고려하여, 본 논문에서는 실시간 트래픽과 비실시간 트래픽으로 구분하여 DABL 알고리즘을 제안하였다. 마지막으로, 본 논문에서는 기존 균등 분할 방식과 DABL 방식의 성능 비교를 위해 시뮬레이션을 수행하였다.

• Ocean Systems Engineering
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• 제4권2호
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• pp.137-150
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• 2014

In the marine industry although there has been significant growth towards safety, security and risk assessments or risk-based strategies such as marine insurance and regulations to avoid the risks of damage to properties and the environment or the prospect of premature death caused by accidents etc, the moves toward managing the risks which are linked directly to the business functions and decision making processes have been very slow. Furthermore in the marine industry most perceptions, methodologies and frameworks of dealing with hazards, risks, safety and security issues are for their assessment rather than their management. This trend reveals the fact that in different marine industry sectors such as logistics and shipping there is a lack of coherent risk management framework or methodology from which to understand the risk-based decisions especially for the purpose of design, construction, operation, management and even decommissioning of the marine related applications. On the other hand risk management is not yet viewed holistically in the marine industry in order to, for example, assign a right person, i.e. risk manager, who can act as a coordinator and advisor with responsibilities that are only specific to risk management. As a result this paper, by examining the present physical borders and risk-based activities in the marine industry, aims to propose an appropriate risk management methodology in addition to the emergent role of risk managers which will enable the industry users initially to become familiar with the concept of risk management at its holistic level. In the later stages this eventually can lead to development of risk management capabilities at an exclusive level and its integration into the marine industry functions in future.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7575-7582
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• 2015

Cyclin E, a key coordinator of the G1 to S transition in the cell cycle, may be deregulated in several malignancies, including breast cancer. The most significant aberration in cyclin E is its elastase mediated proteolytic cleavage into tumor specific low molecular weight isoforms (LMW-Es). LMW-Es are biochemically hyperactive and biologically drive tumorigenesis in transgenic mouse models. Additionally, expression of LMW-Es has been correlated with poor survival in breast cancer cases. Here we determine whether expression of LMW-Es in a breast cancer cell line that is naturally devoid of these deregulated forms would alter their progression through each phase of the cell cycle. The results revealed that LMW-Es expression resulted in an increased doubling time, concomitant with a predominant increase in the population in the S phase of the cell cycle. Moreover, downregulation of p53 in LMW-Es cells resulted in additional shortening of the doubling time and enrichment of cells in the S and G2/M phases of the cell cycle. Furthermore, expression of LMW-Es sensitized cells to ${\beta}$-estradiol (E2) mediated growth and changed expression patterns of estrogen receptor and Bcl-2. Intriguingly, expression of LMW-Es could surpass anti-apoptotic effects raised by p53 upregulation. Taken together these studies suggest that overexpression of LMW-Es in collaboration with p53 loss results in altered g rowth properties of MCF-7 cells, enhancing the oncogenic activity of these ER positive breast cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1791-1796
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• 2014

Background: Colorectal cancer (CRC) is a leading cause of cancer death among Vietnamese Americans, yet screening remains underutilized. We investigated the effectiveness of a culturally tailored DVD intervention in promoting CRC screening among unscreened Vietnamese Americans age 50 and over. Materials and Methods: Using a community-based participatory research approach, we conducted a trial comparing twenty-eight subjects who received a mailed DVD in Vietnamese, with twenty-eight subjects who received a mailed brochure in Vietnamese. Subjects completed telephone surveys at baseline, One-month, and one-year. The primary outcome was receipt of screening. Secondary measures were participants' knowledge, attitudes, and beliefs about CRC screening. Two focus groups explored the intervention's acceptability and effectiveness. Results: At one year, CRC screening rates of 57.1% and 42.9% were observed in experimental and control group respectively (p=0.42), Subjects in both groups showed increased knowledge about CRC after one month. Focus group findings revealed that the DVD was an effective method of communicating information and would help promote screening. Conclusions: The findings suggest that culturally tailored, linguistically appropriate content is more important than the type of media used. This relatively low intensity, low cost intervention utilizing a DVD can be another useful method for outreach to the often hard-to-reach unscreened population.

• 복식문화연구
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• 제18권6호
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• pp.1153-1164
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• 2010

The objective of this study is to analyze the coordination images seen in comprehensive fashion items and their features. This will be done from the viewpoint of both the creativity as well as functional characteristics of items and images. For the method of study, I explored the idea of "snood" style, analyzing its features of 42 pictures appearing from the 2006 S/S to 2010 F/W collection. It is important to note that "snood" style has the characteristics of both a muffler and turtleneck. With looping design connected at both ends, it can be placed around the neck or head, creating the image of wearing a hood. After having examined the selected data and pictures, one can largely divide the exclusive high-fashion image categories into three types: feminine, avant-garde, and finally, active & functional sportive image. First, the orthodox image is widely accepted by most as it has forever evolved within the original tradition of the practically functional muffler(scarf). Second, since the metamorphic image tends to lend itself to free ideas, you can wear a snood around the shoulders like a collar. Worn together with the same type of clothing, the snood can be seen as an effective suit. Third, the aim of image emphasis is to highlight certain points, or make some features more noticeable, as a means of possibly attracting more interest and attention. The image of snood arises out of the use of shapes, colors, and other accessory parts. As mentioned earlier, snood stands out as an independent item instead of just being an accessory to clothing. Its primary function as a style coordinator is emphasized in order to create more distinctive fashion images. Through this study, I thereby intend to provide fashion style data on the latest trends, and high-fashion codes of snood coordination.