• 한국통신학회논문지
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• 제30권10A호
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• pp.965-970
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• 2005

본 연구에서는 IEEE 802.11a 표준 무선랜 단말기에 활용 가능한 SPDT Tx/Rx 스위치 MMICs를 설계 및 제작하였다. 이를 위하여 먼저 핵심이 되는 pHEMT 스위치 소자의 에피구조를 설계하였으며, 한국전자통신연구원(ETRI의 $0.5{\mu}m$ pHEMT 스위치 공정을 이용하였다. 제작된 SPDT형 Tx/Rx 스위치 MMIC는 주파수 5.8 GHz, 동작전압 0/-3V에서 삽입손실 0.68 dB, 격리도 35.64 dB, 그리고 반사손실 13.4dB의 특성을 보였으며, 전력전송능력인 P1dB는 약 25dBm, 그리고 선헝성의 척도인 IIP3는 42 dBm 이상으로 평가되었다. 제작된 스위치 회로의 성능은 상용제품과 비교 분석한 결과 반사손실은 약간 부족하였으나 삽입손실은 비슷한 수준이며, 특히 격리도는 동작전압 ${\pm}$ 3V/0Vv, 주파수 5.8GHz에서 약 8 dB 이상 우수하였다. 이와 같은 여러 가지의 스위치 회로의 성능은 본연구에서 개발된 pHEMT SPDT 스위치는 IEEE802.11a 표준 5GHz 대역 무선랜에 충분히 할용할수 있을 것으로 생각된다.

• 대한전자공학회논문지TC
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• 제47권2호
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• pp.47-55
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• 2010

전력선 통신은 전력선 채널의 특성이 전력선에 연결된 부하에 의해 변화하는 문제점을 가지고 있다. 이러한 문제점을 극복하기 위한 한 가지 방법으로 대역확산(Spread Spectrum) 방식이 사용되어 왔으며, 그 중 DS/SS (Direct Sequence/Spread Spectrum)은 별다른 Hardware의 추가 없이 구현할 수 있다는 장점을 가지고 있다. DS/SS 시스템에서는 의사잡음(PN code)의 Chip수가 길어질 수 록 에러율이 감소하게 되지만, 저속 전력선 모뎀의 경우 긴 Chip수를 사용할 경우 원하는 데이터 전송 속도를 얻어내기 힘들다. Dual-processing Gain을 가지는 Spread Spectrum 시스템은 전력선 잡음의 주기적 특성을 반영하고자 하였다. 그러나 제안되었던 시스템은 잡음의 형태가 전원전압의 1/4주기를 기준으로 대칭적이라는 가정 하에서 적용되어 실제 여러 형태의 전력선 잡음을 반영하지 못하였다. 따라서 본 논문에서는 여러 잡음의 형태에 따라 PN code의 Chip수가 주기적으로 변경되도록 알고리즘을 구현하여 시스템을 구성 후 시뮬레이션 하였다. 시뮬레이션 시 부하의 잡음을 측정 및 모델링하여 시뮬레이션 하였으며, 구성된 시스템은 여러 전력선 채널의 잡음상황 하에서 실제 데이터 전송 속도를 적게 감소시키면서 에러율은 효과적으로 감소시키는 것을 확인하였다.

• 대한소아치과학회지
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• 제35권1호
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• pp.151-158
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• 2008

상 하악 견치는 기능적 관점에서 뿐 아니라 심미적 관점에서도 매우 중요한 치아이다. 그러나 불행히도 견치의 매복은 종종 관찰되며 여러 임상적인 문제점을 유발한다. 상악 견치의 매복이 하악 견치보다 빈번하며, 주로 구개측에 매복되는 것으로 보고되고 있다. 하악의 경우 견치의 매복이 상악보다 드물게 나타나며, 특히 정중선을 지나 전위 매복되는 경우는 매우 드물다. 대부분의 환자에서 증상이 없어 방사선 사진으로 발견되는 경우가 많은데 그 원인은 불분명하고 다양하다. 매복 견치의 치료는 장애물의 존재 여부와 매복 위치와 방향, 맹출 가능한 공간의 유무, 치근의 형성 단계에 따라 맹출 장애 요인을 제거한 후의 주기적인 관찰 및 외과적 노출과 교정적 견인, 치아이식, 외과적 발치 등의 방법으로 이루어진다. 상악 우측 견치의 매복을 주소로 내원한 환아에서는 외과적 노출과 교정적 견인을 시행하였고, 하악 양측 견치의 매복을 주소로 내원한 환아의 경우 견치가 정중선을 지나 전위 매복되어 있어 교정적 견인이 어렵다고 판단되어 자가이식을 시행하였다.

• 대한한방내과학회지
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• 제37권1호
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• pp.77-89
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• 2016

Objectives: The aim of this study was to develop a standard instrument of pattern identification and evaluation for chemotherapy-induced peripheral neuropathy (CIPN).Methods: The advisory committee for this study was organized by 12 professors of traditional Korean medicine from the Korean Association of Traditional Oncology. The items and structure of the instrument were designed based on a review of previous publications. We revised the instrument in consultation with the advisory committee and received additional advice via email.Results: We divided the symptoms and signs of CIPN into four pattern identifications: wind arthralgia (風痺), cold arthralgia (寒痺), dampness arthralgia (濕痺), and arthralgia of the deficiency type (虛痺). We obtained the mean weights to reflect the standard deviations from each symptom of the four pattern identifications, which were scored on a 5-point scale by the advisor committee. After we obtained the answers to discrimination between variable symptoms (變症) and ordinary symptoms (素症) from the 12 experts, we gained the final weight from the combination of the ratio of pattern identification to the number of total answers of the advisory committee and the mean weight.Conclusions: The Instrument on Pattern Identification and Evaluation for CIPN was developed through a discussion between 12 experts. There was a limitation that the validity and reliability of this instrument have not been proven. However, the significance of this study was that it is the first Instrument on Pattern Identification and Evaluation aimed at assessing CIPN in traditional Korean medicine.

• 대한예방한의학회지
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• 제4권1호
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• pp.32-50
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• 2000

On the process of research in the plan on oriental medical participation in the industrial health sponsored by BK21 project, we carried out the oriental medical health examination program for workers during former half-year We reached the conclusion as follows, 1. The oriental medical health examination program is contents and formalities that should be determined by present industrial health system, based on the oriental medical system and scholastic character, and included probability of the western and oriental medical cooperation. 2. The oriental medical health examination program can promote capability of individual health management and productive power of workers, and it is capable to manage on the self-conscious symptoms and macroschophically approach to their environment 3. The oriental medical health examination program that we have developed, is flow as questionare, understanding of working environment, information of result and later management. It is composed of three fields as follow , first, use of pulse diagnostic apparatus, understanding of the health promotion life style, and diagnosis of the oriental medical doctor, second, analysis of constitution, third, photographing for understanding of the musculoskeletal disorders, questionare for musculoskeletal self-conscious symptoms, and diagnosis of oriental medical doctor. 4. The oriental medical health examination program that we have developed, progressive from the view point of health, makes the oriental medical doctor's roll more important. It is the first trial at the western and oriental medical cooperation and characterized by excellence about musouloskeletal disorders. But it need to be improved in aspects of time and specialist on the health examination, diagnostic apparatus, control of examinant and later management. So we think that it needs research on the employment of health examination specialist, establishment of later management system, development of significantly diagnosable standard and assessable form on the health examination, and contents of health examination on the western and oriental medical cooperation.

• Journal of Periodontal and Implant Science
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• 제30권2호
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• pp.419-429
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• 2000

Prevotella intermedia has been implicated as a potent pathogen in many kinds of periodontal, pulpal and periapical diseases. However, it has been isolated from periodontally healthy adults and from edentulous children as well. The intraspecies heterogeneity of Prevotella intermedia has been demonstrated in early studies and finally Shah & Gharbia confirmed the existence of 2 DNA homology groups and proposed dividing Prevotella intermedia into 2 species, Prevotella intermedia and Prevotella nigrescens. This study was designed to examine the frequency of Prevotella intermedia and Prevotella nigrescens in diseased periodontal pockets and healthy gingival sulcus of Korean people by PCR based on 16s ribosomal DNA sequence. One hundred adults who had adult periodontitis but not taken any periodontal treatment or antibiotics during previous 6 months and 50 adults who had healthy periodontal tissue were selected for this study. The sulcular fluid was collected into VMGA by sterilized paper point and diluted to 1,000 times in anaerobic chamber. $100{\mu}{\ell}$ of sample was cultured in $37^{\circ}C$ for 10 days. Among the bacterial colonies, BPB were selected and cultured in BHI broth and then Prevotella intermedia was identified through Gram staining and biochemical test. Identified Prevotella intermedia was cultured again and centrifuged. DNA was extracted from the pellet using several reagents. PCR was performed by previously designed primer. The results were followed. 1. BPB were isolated from 39 of 100 samples of diseased periodontal pockets(39%). 2. Prevotella intermedia was identified from 24 of 39 BPB samples. 3. Among 24 Prevotella intermedia, 21 were confirmed as Prevotella inter - media(87.5) and 2 were confirmed as Prevotella nigrescens(8.33%). 4. BPB were isolated from 9 of 50 samples of periodontally healthy patients. Among them only two were identified as Prevotella intermedia, that is, one was confirmed as Prevotella intermedia and the other was Prevotella nigrescens.

• 에너지공학
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• 제6권1호
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• pp.104-113
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• 1997

본 연구에서는 상용공정모사기인 ASPEN PLUS를 이용하여 건식탄공급, 산소사용 분류층 가스화기인 Shell가스화공정, 저온가스정제공정, GE MS7001FA가스터빈, 삼압.자연순환식 폐열회수보일러, 재열복수식 증기터빈 및 극저온 산소분리공정을 채용한 IGCC시스템에 대하여 성능해석 모델을 개발하고 시스템 성능해석을 위한 민감도분석을 수행하였다. 본 모델의 적정성은 설계조건에서 대상탄을 이용한 정상상태 성능해석 결과를 타 시뮬레이션 결과와 비교함으로서 검증하였다.$^{1)}$ . Illinois#6탄을 대상으로 수행한 시뮬레이션 결과는 투입되는 탄에 함유된 수분의 양이 증가함에 따라 가스화기의 온도가 감소하며, 회분 및 황이 많은 경우에 현열손실이 증가하여 시스템 효율이 감소하였다. 개발된 모델을 이용하여 가스화기의 운전압력, 증기/석탄비율 및 산소/석탄비율에 따르는 시스템의 민감도분석을 수행한 결과 운전압력 증가에 따라 가스화기 노내온도가 상승하며, 가연성가스(CO＋H2) 생성율이 감소하였다. 증기/석탄비율 변화분석에서는 공급증기의 양을 변화시키면 가연성가스의 최고생성점이 보다 낮은 산소/석탄비율에서 나타남을 알 수 있었다. 또한 산소/석탄비율 변화분석에서는 증기/석탄 공급비율 0.2에서 산소/석탄 공급비율이 0.77인 경우에 가장 최적의 운전조건임을 알 수 있었다.

• 가정간호학회지
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• 제7권1호
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• pp.5-14
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• 2000

This study was conducted during the time period of September 1997 to February 1999. in order to provide data concerning important facets of horne care nursing and the degree to which practicing hospital and public health nurses believe themselves to be competent in each area. The study subjects consisted of 610 hospital nurses, 158 public health nurses and 21 other nurses from Seoul and the province of Kyunggi. Korea. Data was collected through self-reporting questionnaires which was used by Kim et al.(1999) to evaluate the status of home health nursing and the varying ideas of self-competence that practicing nurses have. The results of the study were as follows: 1) The mean scores of perceived important components and competencies on home health nursing measured on the Likert 4 point scale were $3.15{\pm}0.36$ for importance. and $2.56{\pm}0.36$ for competency. Of the four categories regarding nursing services, the 'Nursing skill' factor had the highest importance and competency. 2) There were significantly higher scores for hospital nurses' importance components and competencies of home care nursing as compared to those scores for public health nurses. 3) The significant factors of the importance component of home care nursing listed in order of priority were 'general infection control', 'bed sore care skill', 'rehabilitation care', 'keeping maintenance of the client's confidentiality', 'malpractice', 'diabetes patient care', 'ability for problem solving' respectively. In contrast, of low priority in the importance components of home care nursing were 'referring nursing as a job to others'. 'record keeping', 'family dynamics', 'medical equipment', 'economic problems', 'environmental assessment', 'suture removal', 'multidisciplinary coordination' respectively. 4) The high priority of the degree to which practicing nurses believe themselves to be competent in home health nursing were the 'blood sugar test', 'enema skill', 'injection skill', 'skin care', 'bed sore care skill', etc. In contrast, lower competence for home care nursing as perceived by nurses were 'AIDS care', 'family violence care', 'substance abuse care', 'mental health care' respectively.

• 방송공학회논문지
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• 제13권5호
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• pp.622-635
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• 2008

최근에 H.264/AVC 표준을 이용하는 HDTV, IPTV와 같은 고화질 멀티미디어 서비스가 증가하고 있다. 이러한 고화질의 멀티미디어 서비스를 편리하게 이용하기 위해 축소 영상을 이용한 기술이 요구 된다. 그러나 H.264/AVC는 인트라 예측을 사용하기 때문에 종래 표준에 적용되던 주파수 공간에서 축소 영상을 추출하는 방법을 적용할 수 없다. 따라서 H.264/AVC 인트라 프레임으로부터 축소 영상을 주파수 공간에서 추출할 수 있는 방법이 제안되었다. 그러나 인트라 예측의 반올림 오차와 정수연산과 부동소수점 연산 사이에서의 불일치 문제로 인하여 썸네일의 화질을 저하시키는 문제점이 있다. 본 논문에서는 H.264/AVC 비트스트림으로부터의 썸네일 추출법에 대한 보상 방법을 제안한다. 제안하는 방법에서는 썸네일 추출 시 발생하는 오차에 대하여 분석하고, 통계적 모델을 통해 보상값을 제시한다. 실험결과를 통해 D1급 또는 HD급 영상에서 썸네일 영상의 화질을 효과적으로 보상함을 확인할 수 있으며, 속도 저하는 무시할 수 있다.

• Journal of Periodontal and Implant Science
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• 제27권1호
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• pp.117-128
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• 1997

Using barrier membrane, guided bone regeneration(GBR) and guided tissue regeneration(GTR) of periodontal tissue are now widely studied and good results were reported. In bone regeneration, not all cases gained good results and in some cases using GTR, bone were less regenerated than that of control. The purpose of this study is to search for the method to improve the success rate of GBR and GTR by examination of the cause of the failure. For these study, rats and beagle dogs were used. In rat study, 5mm diameter round hole was made on parietal bone of the rat and 10mm diameter of bioresorbable membrane was placed on the bone defects and sutured. In 1 ,2, 4 weeks later, the rats were sacrificed and Masson-Trichrome staining was done and inspected under light microscope for guided bone regeneration. In dog study, $3{\times}4mm^2$ Grade III furcation defect was made at the 3rd and 1th premolar on mandible of 6 beagle dogs. The defects were covered by bioresorbable membrane extending 2-3mm from the defect margin. The membrane was sutured and buccal flap was covered the defect perfectly. In 2, 4. 8 weeks later. the animals were sacrificed and undecalcified specimens were made and stained by multiple staining method. In rats. there was much amount of new bone formation at 2 weeks. and in 4 weeks specimen, bony defect was perfectly dosed and plenty amount of new bone marrow was developed. In some cases, there were failures of guided bone regeneration. In beagle dogs, guided tissue regeneration was incomplete when the defect was collapsed by the membrane itself and when the rate of resorption was so rapid than expected. The cause of the failure in GBR and GTR procedure is that 1) the membrane was not tightly seal the bony defects. If the sealing was not perfect, fibrous connective tissue infiltrate into the defect and inhibit the new bone formation and regeneration. 2) the membrane was too tightly attached to the tissue and then there was no space to be regenerated. In conclusion, the requirements of the membrane for periodontal tissue and bone regeneration are the biocompatibility, degree of sealingness, malleability. space making and manipulation. In this animal study. space making for new bone and periodontal ligament, and sealing the space might be the most important point for successful accomplishment of GBR and GTR.