• 한국전자파학회논문지
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• 제21권11호
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• pp.1240-1247
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• 2010

본 논문은 한반도 지역에 개인 휴대 단말을 사용한 보편적 통신 방송 서비스를 제공하기 위한 S-대역 위성 탑재용 다중 빔 대형 안테나의 전기적 설계 방법에 대해 연구한 것이다. 배열 소자로 급전되는 반사판 형태인 하이브리드 안테나로 다중 빔을 구현하고, 각 빔은 급전 배열의 일부를 사용하여 형성된다. 원하는 빔을 얻기 위해서는 각 배열 소자 신호의 크기와 위상을 최적화해야 하고, 이는 GO(Geometrical Optics) 및 PO(Physical Optics) 해석을 통해 이루어졌다. 또한, EIRP(Effective Isotropically Radiated Power) 요구 사항을 만족하도록 배열 소자의 개수를 최적하였다. 위성에 탑재 가능하도록 제한된 크기의 반사판을 사용하고, 배열 소자의 개수를 최소화하면서도 요구 사항을 만족시킬 수 있는 설계 방법과 그 성능 결과를 본 논문에서 확인할 수 있을 것이다.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.471-473
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• 2002

Public concerns associated with the electromagnetic field (EMF) exposures from mobile phones on human body are increased. Although studies on the effects of the EMF exposures on human have been carried out for a long time, it is not proved yet whether the EMF effect is harmful or not. Based on the scientific results by experts, EMF exposure limits have been regulated as a precautionary approach on the assumption that the EMF effect may be harmful. It is well known that absorbed EMF can be transformed into heat within biological tissues and that thermal effects are related with the specific absorption rate (SAR) distribution. However, the relative magnitude and distribution of the energies are not well defined. Although there is comprehensive information of the thermal effects, most of them come from animal and in vitro studies. Considerable efforts have been made to analyze the EMF absorption model while the actual temperature in the human body has been rarely measured. Temperature changes on the face of a healthy male volunteer were studied. A digital mobile phone of 1.8GHz was used. A digital infrared imaging system (IRIS-5000, Medicore, Seoul, Korea) was applied to take infrared pictures of the face every minute while the volunteer talked over the mobile phone for 20 minutes. The specification of the imaging system was as follows: Temperature resolution = 0.1$^{\circ}C$; Range of temperature measurement = 17～40$^{\circ}C$; Pixel size = 0.9mm ${\times}$ 0.9mm; Frame time = 2.6s; Active temperature of detector = 77$^{\circ}$K. The result showed that temperature of the ear region was increased during the phone call and the region of the temperature increase on the face was expanded as the phone call time increased. Further study is necessary to investigate the temperature rise analytically and quantitatively.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1337-1340
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• 2016

Background: There is a noticeable change in the approach with which women nowadays seek help for diseases like breast cancer, primarily due to awareness campaigns, but what happens after surgical procedures is of great significance too. This study focused on the several psychological connotations attached to mastectomy and how the patients cope. Objective: To understand the pattern of anxiety and level of depression among Pakistani patients undergoing mastectomy. Materials and Methods: The sample size consisted of 88 patients who had undergone mastectomy at the different surgical units of the Civil Hospital, Karachi, from January 2012-December 2014; The questionnaire was administered before they were discharged i.e. within 3 days of surgical procedures. The patients were asked if they were willing to participate in this study, those who agreed signed the consent form and then we preceded by asking questions with a standardized tool. A self made questionnaire was constructed keeping in mind the nature and specification of the disease, which consisted of 20 questions related to anxiety and depression, focusing on a mixture of psychological and physiological symptoms. Results: There were a total of 88 patients out of which 36 (41%) were aged 51 to 60 years, 24 (27.2%) of the patients were in the age category of 41 to 50 years, 17 aged 61 and above (19.3%) and only 11 (12.5%) 30-40 years of age, the youngest of all the age categories. The pattern of depression and anxiety was found to be similar among all age categories, severe depression and anxiety predominating over moderate level of such symptoms, with only relatively few patients sufering mild or no depression symptoms. Conclusions: It was concluded that going through mastectomy leads to moderate to severe levels of depression and anxiety, primarily because the females feel incomplete and insecure after losing a part of themselves.

• 마이크로전자및패키징학회지
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• 제10권3호
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• pp.43-55
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• 2003

최근 IT산업의 발달과 그에 따른 전자부품기술의 발전이 가속화됨에 따라, 전자부품의 경박 단소화 및 고성능에 대한 요구는 전자패키지 (electronic package) 및 반도체기판(PKG substrate) 업체들로 하여금 고밀도의 입출력(I/O)과 우수한 열적, 전기적 특성을 보유하면서 높은 양산수율로 제품이 가격경쟁력을 갖도록 유도하고 있다. 이러한 경향에 따라 세계적인 반도체 회사(chip-maker)들은 더욱 혹독한 조건의 신뢰성 표준을 마련하여 제반 산업에 전반적인 적용을 요구하고 있으며, 환경친화 및 고주파, 고성능의 특성을 지닌 새로운 소재를 개발하도록 촉구하고 있는 실정이다. 반도체기판은 구성소재에 따라 구현되는 특성의 범위가 매우 크므로 우수한 특성의 소재를 반도체기판에 적용할 때 고객의 요구조건에 충분히 만족시킬 수 있을 것으로 기대된다. 따라서, 기판업계에서는 우수한 특성을 나타내는 원자재의 개발 및 수급이 절실하게 되었으며 급변하는 원자재의 기술 동향에 대한 분석은 향후 전자패키지 및 기판제품의 경쟁력을 향상시킬 수 있을 것이므로 본 연구에서는 최신 반도체기판 원자재의 기술 동향과 원자재의 특성을 분석하고자 하였다.

• 대한인간공학회지
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• 제23권4호
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• pp.35-43
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• 2004

The purpose of this study is to redesign a letter sorting station and to present the optimal work-space through the ergonomic analysis of the sorting station for reducing the 'Work-Related MusculoSkeletal Disorders(WMSDs)'. We surveyed the work environment in terms of the reason causing WMSDs. According to the survey results, Deltoid on the arm, Trapezius on the shoulder and Erector Spinae on the waist are most frequent attacking parts. Accordingly, We classified sorting stations by the horizontal work-space(Level 1, Level 2, Level 3) and the vertical work space(Level 1, Level 2) based on the criteria of ergonomic optimal work-space. In addition we improved the sorting station through investigation and analysis of the work-load regard the each defined work-space. In order to analyze the effect of the horizontal and vertical work-space, subjects carried out simulated sorting tasks. Each level(Level 1, Level 2, Level3) of the horizontal work-space is significant regarding each muscles(the shoulder, arm and waist), and each level(Level 1, Level 2) of the vertical work-space is significant regarding the arm and waist, but not shoulder. Finally, we founded the difference of work-load according to the work-spaces. Then, it is necessary to improve the work-space causing the high work-load(Level 3 of the horizontal work-space). Then, this study presented the specification of a sorting station which is suitable to the korean body size, and constructed the 3D shaped model of the stations by the ergonomic analysis.

• 한국환경보건학회지
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• 제28권2호
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• pp.161-171
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• 2002

The number of food establishments selling raw and convenience foods are increasing in Korea, and people enjoy purchasing and eating foods at these shops. However, there are only a few reports on the temperature control of the refrigerators and freezers at retail food shops. This study was performed to investigate the temperature control of refrigerators and freezers in retail food shops in Daegu. The survey was carried out from July 20 to August 30 in 2001. The trained surveyors visited the twenty retail food shops (four department stores, eight marts/supermarkets and eight convenience stores) in the 8 major areas of Daegu and inspected the temperature control of 48 refrigerators for dairy products, fruits & vegetables, and rolled rice & sandwiches, and 52 freezers for ice cream & sherbet, frozen food, and frozen fish. The percentage of the refrigerators, and freezers with unsafe temperatures higher than the recommended safe temperature (10℃ for refrigerators, and -18℃ for freezers) was 42%; 45.8% in refrigerators; 38.5% in freezers. On an average, the bigger the size of the shop, the better than the other freezers. On the other hand, the temperature control of refrigerator for fruits & vegetables was the worst because they were usually open. Actual temperatures in the refrigerators and freezers were found to be significantly higher than the reading on the thermometers attached to the refrigerators and freezers(p<0.05). These results indicate that temperature control of refrigerators and freezers at retail food shops should be monitored several times each day, and should have strict inspection. There should be more detailed legal standard and specification for temperature control of refrigerators and freezers at retail food shops to prevent foodborne illness from unsafely stored food.

• Asian Pacific Journal of Cancer Prevention
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• 제15권24호
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• pp.10637-10642
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• 2015

Background: Section 5 of India's tobacco control legislation "Cigarettes and Other Tobacco Products Act (COTPA), 2003"comprehensively prohibits all kinds of tobacco advertisement, promotion and sponsorship (TAPS), but permits advertisments at the point-of-sale (POS) under certain conditions. This provision has been exploited by the tobacco companies to promote their products. Objective: To measure compliance with the provisions of Section 5 of Indian tobacco control legislation (COTPA, 2003) at point of sale. Materials and Methods: A cross-sectional survey using an observation checklist was conducted in 1860 POS across three jurisdictions (Chennai city, District Vadodara and District Mohali) in India. Results: The most common mode of advertisement of tobacco products was product showcasing (51.1%), followed by dangles (49.6%), stickers (33.8%) and boards (27.1%). More than one fourth of POS were found violating legal provisions for displaying advertisement boards in one or other forms (oversized, extended to full body lenth of POS, displayed brandname/packshot and promotional messages). Advertisement boards (16.3%) without health warnings were also found and wherever found, more than 90% health warning were not as per the specification in respect to size, font and background color. Conclusions: Point of sale advertising is aggressively used by the tobacco industry to promote their products. There is an urgent need of effective implementation of a comprehensive ban on tobacco product advertisement, promotion and sponsorship at point of sale.

• 한국정보통신학회논문지
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• 제10권5호
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• pp.812-820
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• 2006

최근 대부분의 전송기술(LAN 뿐만 아니라 MAN과 WAN까지)이 이더넷으로 통일되는 경향에 힘입어, 예전에 비하여 이더넷은 대단한 주목을 받게 되었다. 하드웨어 설계를 위해 10Gbps 이더넷 Data Link 계층의 MAC 코어를 C언어를 이용하여 성능평가를 실시하여 내부 FIFO의 크기를 도출하였다. 본 논문에서는 VHDL 언어와 Xilinx ISE 6.2i 툴을 이용하여 상위 계층 인터페이스, 전송엔진, 플로우 컨트롤 블록, 수신엔진, 정합 부계층(Reconciliation Sublayer), 초기설정 블록, 상태전송 블록, XGMII 인터페이스 블록으로 구성되는 10Gbps 이더넷용 MAC(Media Access Control)코어를 설계하여 Model_SIM 5.7G 시뮬레이터를 이용하여 검증하였다. 10Gbps 이더넷의 권고안에서는 10Gbps를 지원하기 위해 64비트 데이터 패스를 갖는 MAC 코어는 156.25MHz를 지원해야 하는데, 설계된 MAC 코어는 64비트의 데이터를 처리하고 168.549MHz를 지원하여 최대 10.78Gbps의 데이터 처리를 지원한다. 이는 100bps 이상의 고속의 데이터 처리가 요구되는 응용분야에 적합하다.

• 정보처리학회논문지D
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• 제18D권6호
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• pp.433-442
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• 2011

소프트웨어의 규모가 커지고 다양해짐에 따라 고객이 원하는 요구사항을 정확하게 이해하여 표현하는 것의 중요성이 강조되고 있다. 특히 개발 초기에 요구사항은 추상적이고 개념적이기 때문에 핵심적인 시스템의 요구사항을 도출해서 명세하는 작업은 쉬운 일이 아니다. 기술적인 측면에서 이론적으로 다양한 분석과 검증기법이 소개되고 있지만 실무적으로는 요구사항을 명확하게 도출하기 힘들다. 본 논문에서는 고객이 원하는 요구사항을 명확하게 도출하기 위해, 텍스트언어학(textlinguistics)의 거시구조 개념을 이용한다. 먼저, 서술적으로 명세 된 요구사항을 텍스트언어학(textlinguistics)의 거시구조로 분석하였고 다음으로 거시규칙을 적용하여 거시명제를 도출하여 요구사항을 명확히 정의하도록 하였다. 마지막으로 도출된 거시명제를 이용하여 Use-case Model로 문서화하는 방법을 제시하도록 한다.

• 한국통신학회논문지
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• 제34권3C호
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• pp.297-303
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• 2009

집적 영상 기술은 잘 알려진 3D 영상 기록 및 디스플레이 기술이다. 집적 영상에서 사용되는 대용량 데이터는 3D 영상을 저장하고 전송하기 위한 압축 기법을 요구한다. 기존의 압축 방법에서는 동일한 기록 시스템을 사용한 다할 지라도 요소 영상의 데이터 크기가 3D 물체의 위치, 조명과 렌즈 배열 등의 다양한 기록 조건에 따라 크게 달라진다. 본 논문에서는 기록 조건에 따른 요소 영상 특성의 의존성을 줄이기 위하여 집적 영상에서 요소 영상의 분할 영역을 이용한 압축 기법이 제안된다. 제안된 기법은 각 3D 물체의 픽업 위치에 따른 요소 영상의 지역적 유사성을 고려하여 향상된 압축률을 보여준다. 제안된 기법의 효율성을 보이기 위하여, 다양한 요소 영상들이 픽업되었고 표준 MPEG-4를 이용하여 압축이 진행되었다. 실험을 통하여 제안된 압축 기법이 기존의 압축 방식에 비하여 9%의 압축률 향상을 보였다.