• 제어로봇시스템학회논문지
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• 제20권12호
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• pp.1225-1230
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• 2014

This paper investigates the group average-consensus and group formation-consensus problems for first-order multi-agent systems. The control protocol for group consensus is designed by considering the positive adjacency elements. Since each intra-group Laplacian matrix cannot be satisfied with the in-degree balance because of the positive adjacency elements between groups, we decompose the Laplacian matrix into an intra-group Laplacian matrix and an inter-group Laplacian matrix. Moreover, average matrices are used in the control protocol to analyze the stability of multi-agent systems with a fixed and undirected communication topology. Using the graph theory and the Lyapunov functional, stability analysis is performed for group average-consensus and group formation-consensus, respectively. Finally, some simulation results are presented to validate the effectiveness of the proposed control protocol for group consensus.

• Asia pacific journal of information systems
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• 제9권1호
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• pp.143-163
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• 1999

This study investigates the effect of group size on group performance, here the quality of group decision, Four effects are proposed and tested in a field experimental setting : (1) the relationship between the group size and the distribution of individual's problem-solving ability ; (2) the change of the group decision quality as group size increases ; (3) the relationship between the group decision quality and the quality of the best/worst member as group size increases ; (4) the relationship between the group decision quality and the average quality of individuals in the group as group size increases. Data showed that contrary to the exiting results, group decision quality was not improved with the group size. Rather, it showed a little tendency that group decision quality was worsened with the group size. Data also showed that consensus-oriented group decision making process produced the compromised output. Thus, group decision quality was not better than the average group members'. The opinion of the best member was not accepted. The implications of the findings are discussed for the development of a Korean GSS.

• 대한간호학회지
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• 제17권1호
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• pp.9-23
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• 1987

Nursing service, as the largest user of labor resources, has become concerned about appropriate allocation of staffing resources. Therefore, this project was designed to measure quantitatively the direct nursing care provided to patients and to develop a new patient classification system based on the direct nursing care activities. The initial step in the development of the classification instrument was to identify the content of direct nursing activities. The frequency with which these activities were carried out, the total time spent in carrying them out and the average time for one performance of each of the nursing activities was calculated. The next step was to select the items for the classification instrument taking into account these direct nursing activities. A list of 40 items was prepared. These items were then classified into 8 major categories: personal hygiene, moving ＆ exercise, nutrition & elimination, observation, medication, treatment, collecting specimens and other care activities for severity ill patients. Each item was assigned a value unit based on the average time required by the nursing staff to complete the specific item. The third step was to determine the practicality of the items and value units, so an attempt was made to establish content validity for these items and units by obtaing a consensus from 8 head nurses, representing eight different departments. The 4th step was to conducted a pilot study to establish the score range for the classification boundaries. For this purpose an instrument was designed using the list of items and value units and a prepared classification criteria as a guideline to validate the patient classification. A judgment group consisting of 52 supervisory nurses and head nurses were asked to select the proper patient to fit each classification criteria and to fill out the instrument for each patient. The total value unit and the frequency for each classification group was calculated. According to the frequency distribution, the score range for the classification group was determined as follows : 0~15 for groupI, 16~30 for group II, 31~50 for group III, and above 51 for group IV. Finally a patient classification form was developed.

• Journal of Chest Surgery
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• 제49권5호
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• pp.361-365
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• 2016

Background: Sternal fractures are relatively rare, and caused mainly by blunt anterior chest wall trauma. In most cases, sternal fractures are treated conservatively. However, if the patient exhibits problematic symptoms such as intractable chest wall pain or bony crepitus due to sternal instability, surgical correction is indicated. But no consensus exists regarding the most appropriate surgical method. We analyzed the results of surgical fixation in cases of sternal fracture in order to identify which surgical method led to the best outcomes. Methods: We retrospectively reviewed the medical records of patients with sternal fractures from December 2008 to December 2011, and found 19 patients who underwent open reduction and internal fixation of the sternum with a longitudinal plate (L-group) or a T-shaped plate (T-group). We investigated patients' characteristics, clinical details regarding each case of chest trauma, the presence of other associated injuries, the type of open reduction and fixation, whether a combined operation was performed, and postoperative complications. Results: Of the 19 patients, 10 patients (52.6%) were male, and their average age was 56.8 years (range, 32 to 82 years). Seven patients (36.8%) had isolated sternal fractures, while 12 (63.2%) had other associated injuries. Seven patients (36.8%) were in the L-group and 12 patients (63.2%) were in the T-group. Three patients in the L-group (42.9%) showed a loosening of the fixation. In all patients in the T-group, the fracture exhibited stable alignment. Conclusion: Open reduction and internal fixation with a T-shaped plate in sternal fractures is a safer and more efficient treatment method than treatment with a longitudinal plate, especially in patients with a severely displaced sternum or anterior flail chest, than a longitudinal plate.

• Journal of Periodontal and Implant Science
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• 제42권3호
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• pp.88-94
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• 2012

Purpose: The use of appropriate instruments to clean surfaces with minimal change, is critical for the successful maintenance of a dental implant. However, there is no consensus about the type and methodology for such instruments. The aim of this study was to characterize changes in the roughness of titanium surfaces treated by various scaling instruments. Methods: Thirty-seven identical disks (5 mm in diameter) were investigated in this study. The specimens were divided into eight groups according to the types of instrumentation and the angle of application. Ultrasonic scaling systems were applied on a titanium disk to simulate standard clinical conditions. The equipment included a piezoelectric ultrasonic scaler with a newly developed metallic tip (NS group), a piezoelectric ultrasonic scaler with a conventional tip (CS group), a piezoelectric root planer ultrasonic scaler with a conventional tip (PR group), and a plastic hand curette (PH group). In addition, the sites treated using piezoelectric ultrasonic scaler systems were divided two sub-groups: 15 and 45 degrees. The treated titanium surfaces were observed by scanning electron microscopy (SEM), and the average surface roughness (Ra) and mean roughness profile depth (Rz) were measured with a profilometer. Results: SEM no significant changes in the titanium surfaces in the NS group, regardless of the angle of application. The PH group also showed no marked changes to the titanium surface, although some smoothening was observed. All CS and PR sites lost their original texture and showed irregular surfaces in SEM analysis. The profilometer analysis demonstrated that the roughness values (Ra and Rz) of the titanium surfaces increased in all, except the PH and NS groups, which showed roughness decreases relative to the untreated control group. The Ra value differed significantly between the NS and PR groups (P<0.05). Conclusions: The results of this study indicated that changes in or damage to titanium surfaces might be more affected by the hardness of the scaler tip than by the application method. Within the limitations of this study, the newly developed metallic scaler tip might be especially suitable for peri-implant surface decontamination, due to its limited effects on the titanium surface.

• 전자공학회논문지SC
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• 제43권3호
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• pp.78-84
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• 2006

구순열 비변형 환자의 상태, 수술결과 등을 객관적으로 평가할 수 있는 방법의 개발은 구순열의 수술의 술기 등의 평가 및 발전에 많은 도움을 줄 수 있을 것으로 생각되나 아직은 미진하다. 이에 본 논문은 구순열 환자의 사진을 이용해 다음과 같은 요인들을 분석하여 구순열 비변형 정도를 정량적으로 평가하고자 하였다. (1) 비공의 각도 (2) 비공의 중심점 및 중심점사이의 거리 (3) 중첩된 비공의 면적 (4) 비공의 중첩된 면적의 비 등을 각각 비교하였다. 먼저, 8개의 분석요인을 이용하여 임상의 평가점수에 대한 회귀분석을 통하여 회귀식을 획득하였다. 구순열 환자의 수술 경험이 많은 성형외과 의사 세 사람이 상기 대상 환자의 수술 후의 결과를 100 점 만점과 10점 간격으로 판정하였다. 세 명의 성형외과 의사와 개발된 프로그램을 이용한 세 명의 일반인으로부터 얻어진 평가점수의 재현성은 각각 $10.8{\pm}4.6%,\;7.4{\pm}1.8%$로 개발된 프로그램을 이용한 분석이 더 높은 재현성을 보였다. 일치도를 나타내는 kappa 통계량은 세 명의 성형외과 의사에서는 0.43, 세 명의 일반인에서는 0.83으로 프로그램을 이용한 일반인의 일치도가 훨씬 더 높게 나타났다. 회귀분석을 통한 평가와 임상의의 평가점수에서의 상관관계는 0.642이었으며, 신경회로망을 통한 평가와 임상의의 평가점수에서의 상관관계는 0.798로 신경회로망을 통한 분석이 임상의의 평가점수와 상관관계가 더 높은 것으로 나타났다. 결론적으로, 개발된 신경회로망 모델은 의사의 주관적인 평가보다 더 높은 재현성, 일치도, 상관관계를 보여주며 이는 임상의에서 구순열 비변형의 정도를 객관적이고 손쉽게 적용할 수 있을 것이라 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.331-339
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• 2008

The genetic structure and diversity of 15 Chinese indigenous chicken breeds was investigated using 29 microsatellite markers. The total number of birds examined was 542, on average 36 birds per breed. A total of 277 alleles (mean number 9.55 alleles per locus, ranging from 2 to 25) was observed. All populations showed high levels of heterozygosity with the lowest estimate of 0.440 for the Gushi chickens, and the highest one of 0.644 observed for Wannan Three-yellow chickens. The global heterozygote deficit across all populations (FIT) amounted to 0.180 (p<0.001). About 16% of the total genetic variability originated from differences between breeds, with all loci contributing significantly to this differentiation. An unrooted consensus tree was constructed using the Neighbour-Joining method and pair-wise distances based on marker estimated kinships. Two main groups were found. The heavy-body type populations grouped together in one cluster while the light-body type populations formed the second cluster. The STRUCTURE software was used to assess genetic clustering of these chicken breeds. Similar to the phylogenetic analysis, the heavy-body type and light-body type populations separated first. Clustering analysis provided an accurate representation of the current genetic relations among the breeds. Remarkably similar breed rankings were obtained with all methods.

• Archives of Plastic Surgery
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• 제33권2호
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• pp.193-197
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• 2006

Pulmonary thromboembolism is often clinically silent and difficult to diagnose, and can be fatal to patients with belated treatment. This complication is seen in patients who underwent TRAM breast reconstruction. Multiple factors are involved in this disease such as the presence of malignancy itself, major surgery and therapy-related interventions. TRAM surgery is a lengthy procedure involving mastectomy, flap surgery and abdominoplasty. The purpose of this study is to evaluate the incidence and the correlation between presurgical risk factors(BMI and age) of symptomatic pulmonary thromboembolism after TRAM surgery and the incidence. From July 2001 to March 2005 a total of 384 pedicled TRAM reconstruction of breast was performed in 382 patients at Asan Medical Center. The average of Body mass index was $21.9kg/m^2$ and mean age of the patients was 37.9 years old. We diagnosed symptomatic pulmonary thromboembolism using ventilation/perfusion lung scan and pulmonary embolism computed tomography. Incidence of in-hospital symptomatic pulmonary thromboembolism was 1.3%. BMI and age showed no significant statistical relationship to pulmonary thromboembolism. But the incidence of symptomatic pulmonary thromboembolism in obese patients (BMI > 25) was 3.75%. According to the guideline of the 7th American College of Chest Physicians Consensus Conference on Antithrombotic and Thrombolytic Therapy, the incidence of 3.75% was classified as high risk group. The prevention of pulmonary thromboembolism should be considered in cases of obese patients with low molecular weight heparin(BMI > 25).

• 식품과학과 산업
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• 제51권3호
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• pp.209-217
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• 2018

본 연구는 식품안전 분야 기술수준을 주요 5개국과 비교하여 현재의 기술수준에 대한 평가와 기술개발의 기초자료로 활용하기 위하여 수행하였다. 식품안전 분야 기술수준 평가 결과 미국이 모든 분야에서 최상의 기술을 보유한 것으로 나타났으며, 우리나라의 경우 최고기술 보유국인 미국과 비교할 때 4위를 차지하는 것으로 나타났다. 또한, 우리나라는 논문 점유율과 영향력은 주요 5개국 기준으로 최하위를 차지하였으며, 특허 기술력으로 볼 때, 특허 인용도는 3위, 특허 영향력은 1위로 나타나 점유율은 낮으나 질적으로 우수한 특허를 보유하고 있는 것으로 나타났다. 본 연구결과로 볼 때 식품안전 분야의 현재 수준의 기술을 향상시키기 위해서 전문인력 양성을 위한 정책적 접근이 필요할 것으로 사료되며, 해당 분야의 논문 저술활동이 저조하므로 연구결과 확산활동에 노력이 필요하다고 판단된다. 전문가들의 추가 제언 내용으로는 식품분야 관련 연구자 및 종사자의 역량강화를 위한 제도 마련과 지속적인 교육을 통해 안전기술에 대한 이해도 증진이 지속적으로 필요하다는 것과 향후 연구 기획시 실수요자의 의견을 반영할 수 있는 상향식 연구지원 방식도 고려하는 것이 필요하다는 의견이 제시되었다. 또한, 식품 안전기술은 정부 주도의 투자 뿐만 아니라 산업계 및 연구계가 함께 발전시켜 나가야하는 분야로 민간 투자 활성화를 유도할 수 있는 제도마련도 필요하다는 의견이 있었다. 본 연구를 통해 도출된 결과를 바탕으로 평가대상 기술의 속성이나 특성을 고려하여실효성 있는 기술개발 및 진흥 관련 계획수립이 이뤄져야 할 것으로 생각되며, 이번 연구에서는 식품안전 분야의 식품과 영양 안전관리 15개 기술로 제한하였으나, 향후 에는 식품안전 분야 신기술 및 세부기술에 대한 기술수준 평가도 개별적으로 수행하는 것을 고려하여야 할 것이다.

• 수면정신생리
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• 제26권2호
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• pp.86-103
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• 2019

목 적 : 본 연구는 대한수면의학회로부터 수면에 대한 전문가로 구성된 집단을 모집하여 델파이 기법을 통해 수면진정제의 안전사용지침을 개발하고자 한다. 방 법 : 대한수면의학회 소속 수면 전문가 15인을 모집하였으며, 전문가들을 대상으로 웹 기반의 3차 델파이 조사를 시행하였다. 첫 델파이 조사는 39개의 문항으로 구성되었으며 한국에서 수면진정제 사용의 문제점을 환기하고, 안전사용지침에 포함되어야 할 항목들에 대한 조사를 시행하였다. 두번째 델파이 조사는 21개의 문항으로 구성되었으며 수면진정제 처방에 있어서 임상적으로 중요한 문제들에 대한 구체적인 의견을 수집하였다. 세번째 델파이 조사는 Likert 척도를 이용하여 1, 2차 조사를 통해 도출한 수면진정제 안전사용지침에 대한 의견 동의율을 구하고 이를 바탕으로 수면진정제 안전사용지침을 개발하였다. 결 과 : 17개 항목에 대한 전문가들의 의견 동의율이 중앙값 4점 이상이었으며 평균 4.12, 표준편차 0.32를 보였다. 본 연구를 통해 개발된 수면진정제 안전사용지침은 수면진정제의 처방, 유지, 그리고 감량 및 중단에 대한 총 13개의 지침을 제안한다. 결 론 : 증가하는 불면증 환자와 수면진정제 처방에도 불구하고 한국 임상 현실에 맞는 안전사용지침이 부재하였는데, 본 연구를 통해 개발된 수면진정제 안전사용지침을 통해 한국 임상에서 수면 비전문가들이 수면진정제를 처방할 시에 안전하고 효과적인 처방을 위해 유용하게 사용될 수 있을 것이다.