• ETRI Journal
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• 제29권5호
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• pp.655-666
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• 2007

There are nodes and edges in a topological map. Node data has been used as a main source of information for the localization of mobile robots. In contrast, edge data is regarded as a minor source of information, and it has been used in an intuitive and heuristic way. However, edge data also can be used as a good source of information and provide a way to use edge data efficiently. For that purpose, we define a data format which describes the shape of an edge. This format is called local generalized Voronoi graph's angle (LGA). However, the LGA is constituted of too many samples; therefore, real time localization cannot be performed. To reduce the number of samples, we propose a compression method which utilizes wavelet transformation. This method abstracts the LGA by key factors using far fewer samples than the LGA. Experiments show that the LGA accurately describes the shape of the edges and that the key factors preserve most information of the LGA while reducing the number of samples.

• Journal of Gastric Cancer
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• 제22권3호
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• pp.184-196
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• 2022

Purpose: Total or proximal gastrectomy of the upper-third early gastric cancer (u-EGC) often causes severe post-gastrectomy syndrome, suggesting that these procedures are extremely invasive for patients without pathologically positive lymph node (LN) metastasis. This study aimed to evaluate the clinical applicability of a stomach function-preserving surgery, local resection (LR), with prophylactic left gastric artery (LGA)-basin dissection (LGA-BD). Materials and Methods: The data of patients with u-EGC (pathologically diagnosed as T1) were retrospectively analyzed. Total gastrectomy was performed in 30 patients, proximal gastrectomy in 45, and subtotal gastrectomy in 6; the LN status was evaluated assuming that the patients had already underwent LR + LGA-BD. This procedure was considered feasible in patients without LN metastases or in patients with cancer in the LGA basin. The reproducibility of the results was also evaluated using an external validation dataset. Results: Of the 82 eligible patients, 79 (96.3%) were cured after undergoing LR + LGA-BD, 74 (90.2%) were pathologically negative for LN metastases, and 5 (6.1%) had LN metastases, but these findings were only observed in the LGA basin. Similarly, of the 406 eligible tumors in the validation dataset, 396 (97.5%) were potentially curative. Tumors in the lesser curvature, post-endoscopic resection status, and small tumors (<20 mm) were considered to be stronger indicators of LR + LGA-BD as all subpopulation cases met our feasibility criteria. Conclusions: More than 95% of the patients with u-EGC might be eligible for LR + LGA-BD. This function-preserving procedure may contribute to the development of u-EGC without pathological LN metastases, especially for tumors located at the lesser curvature.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.2017-2022
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• 2004

Data association is a process that matches a recent observation with known data set, which is used for the localization of mobile robots. Edges in topological maps have rich information which can be used for the data association. However, no systematic approach on using the edge data for data association has been reported. This paper proposes a systematic way of utilizing the edge data for data association. First, we explain a Local Generalized Voronoi Angle(LGA) to represent the edge data in 1-dimension. Second, we suggest a key factor extraction procedure from the LGA to reduce the number by $2^7-2^8$ times, for computational efficiency using the wavelet transformation. Finally we propose a way of data association using the key factors of the LGA. Simulations show that the proposed data association algorithm yields higher probability for similar edges in computationally efficient manner.

• 한국시스템다이내믹스연구
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• 제14권4호
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• pp.143-163
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• 2013

This study is firstly aiming at diagnosing the present problems of evaluating the performance, especially in the field of disaster and safety management, of LGA (Local Government Authorities) in Korea. The study also deals with developing alternatives to solve a series of barrier factors revealed during the evaluation process using System Dynamics. This paper therefore presents literature review including the official documents published by the government and the performance evaluation studies of LGA. Moreover the authors analyze the current practice of the CELG (Combined Evaluation of Local Governments) as performance management, address and map a series of barrier factors in the CELG process to elaborate the CLDs (Causal-Loop Diagrams) and find solutions using system thinking with the CLDs. According to the analysis results, the core barrier factors to overcome is lack of proactive indicators/indices in the current practice of the CLEG. The authors therefore recommend to develop more proactive indicators that leads to avoid difficulties in measuring the LGA output, as well as to lessen the burden in competition for rankings and goal of the displaced.

• Journal of Gastric Cancer
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• 제16권2호
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• pp.72-77
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• 2016

Purpose: During laparoscopic gastrectomy, an aberrant left hepatic artery (ALHA) arising from the left gastric artery (LGA) is occasionally encountered. The aim of this study was to define when an ALHA should be preserved during laparoscopic gastrectomy. Materials and Methods: From August 2009 to December 2014, 1,340 patients with early gastric cancer underwent laparoscopic distal gastrectomy. One hundred fifty patients presented with an ALHA; of the ALHA was ligated in 116 patients and preserved in 34 patients. Patient characteristics, postoperative outcomes and perioperative liver function tests were reviewed retrospectively. Correlations between the diameter of the LGA measured on preoperative abdominal computed tomography and postoperative liver enzyme levels were analyzed. Results: Pearson's correlation analysis showed a positive correlation between the diameter of the LGA and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels on postoperative day 1 in the ALHA-ligated group (P=0.039, P=0.026, respectively). Linear regression analysis estimated the diameter of the LGA to be 5.1 mm and 4.9 mm when AST and ALT levels were twice the normal limit on postoperative day 1. Conclusions: We suggest preserving the ALHA arising from a large LGA, having diameter greater than 5 mm, during laparoscopic gastrectomy to prevent immediate postoperative hepatic dysfunction.

• Clinical and Experimental Pediatrics
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• 제46권5호
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• pp.447-453
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• 2003

목 적 : 당뇨병 산모의 빈도가 증가함에 따라 이들에서 태어난 신생아에서 거대아, 대사성 합병증, 선천성 기형 및 분만 손상 등의 주산기 유병률이 높아 문제가 되고 있다. 본 연구는 당뇨병 산모아에서 출생 체중에 따른 주산기 합병증 및 주산기 인자에 차이가 있는지 알아보고자 하였다. 방 법: 1996년 1월부터 2002년 3월까지 전남대학교병원에서 입원하였던 단태 임신의 당뇨병 산모와 그 신생아 중, 부당 경량아와 재태 연령 30주 미만의 환아를 제외한 301례를 대상으로 하여 산모에서는 체중과 신장, 분만력, 당화 혈색소치, 당뇨병의 분류 및 치료를, 그리고 신생아에서는 대사성 합병증, 분만 손상 및 심기형을 포함한 선천성 기형에 대해 의무 기록지를 통하여 후향적으로 분석하였으며, 대상아를 부당 중량아군(1군, 162명)과 적정 체중아군(2군, 139명)으로 나누어 합병증 및 주산기 인자의 차이를 조사하였다. 결 과: 대사성 합병증은 저마그네슘혈증(37.5%), 황달(21.3%), 저혈당증(11.0%) 및 저칼슘혈증(7.0%) 순이었으며, 분만 손상은 59명(19.6%), 동반된 선천성 기형은 동맥관 개존을 포함하여 75명(24.9%)이었고 심기형이 가장 많았다. 부당 중량아군(1군)과 적정 체중아군(2군) 두 군간의 주산기 합병증을 비교해 본 결과, 1군에서 2군에 비해 황달의 빈도(27.7% vs. 16.7%, P<0.05)와 저혈당증 빈도(15.6% vs. 7.4%, P=0.02), 빈호흡의 빈도(10.6% vs. 3.6%, P<0.05) 및 분만 손상의 빈도(24.1% vs. 14.5%. P<0.05)가 의의 있게 높았으며, 심실 중격이 두터웠다($5.5{\pm}3.1mm$ vs. $4.7{\pm}1.1mm$, P<0.05). 당뇨병 산모아의 출생 체중에 영향을 줄 수 있는 주산기 인자를 비교해 본 결과, 1군에서 산모의 키와 임신 전 체중 및 임신 기간 중 체중 증가가 의의 있게 컸고(모두 P<0.01), 산모가 임신 기간 동안 임신성 당뇨를 인지하지 못했던 경우가 더 많았다(21.7% vs. 6.6%, P<0.01). 결 론 : 당뇨병 산모아에서 출생 체중군에 따른 주산기 합병증은 부당 중량아군에서 적정 체중아군에 비해 황달, 저혈당증 및 분만 손상의 빈도가 의의 있게 높았고 심실 중격 두께가 두터웠으며, 산모의 키가 더 크고 임신 전 체중 및 임신 기간 동안 체중 증가가 컸으므로, 부당 중량아를 분만할 수 있는 고위험 임산부에 대한 주의 깊은 검사와 관리가 필요하리라 사료된다.

• Clinical and Experimental Pediatrics
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• 제51권7호
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• pp.722-728
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• 2008

목 적 : 건강한 만삭아의 제대혈에서 아디포넥틴, 렙틴, 인슐린, IGF-I, IGFBP-3를 측정하여 출생체중, 신장, 지방량과의 관계를 알아보고자 하였다. 또한 적정 체중아 그룹에서 이 호르몬들의 출생후 1개월 동안 변화에 대해서 살펴보기로 하였다. 방 법 : 임신과 관련된 합병증이 없었던 산모에서 태어난 200명의 건강한 만삭아(남아 109명, 여아 91명)를 대상으로 하여 제대혈을 채취하여 혈장과 혈청을 분리하였고 출생체중, 출생신장, 머리둘레, 가슴둘레, 피부두께를 측정하였으며 폰더랄지수를 계산하였다. 대상 신생아들을 출생체중에 따라 AGA (n=132), SGA (n=29), LGA (n=39)의 세 그룹으로 나누었다. 적정체중아 중 15명에서 생후 3일, 7일, 30일에 신생아의 혈액을 채취하여 제대혈과 같은 방법으로 분리하였고 체중과 신장을 측정하였다. 결 과 : 아디포넥틴과 인슐린, IGF-I은 AGA, LGA군보다 SGA군에서 더 낮았다. 렙틴은 AGA, SGA군보다 LGA군에서 더 높았다. 아디포넥틴과 렙틴, 인슐린, IGF-I, IGFBP-3는 출생체중과 피부두께의 합과 양의 상관관계에 있었다. 출생 시 신장과 양의 상관관계를 보인 호르몬은 아디포넥틴, 렙틴, IGF-I이었다. 아디포넥틴은 렙틴과 양의 상관관계를 보였으나 인슐린, IGF-I, IGFBP-3와는 상관관계가 없었다. IGF-I은 남아보다 여아에서 더 높은 수치를 보였다. 출생 후 1개월 동안 렙틴은 생후 7일까지는 생리적 체중감소와 더불어 감소하다가 그 후 증가하였고 IGF-I 또한 생후 3일에 감소하다가 1개월 후 급격한 증가를 보였다. 결 론 : 아디포넥틴과 렙틴, 인슐린, IGF-I, IGFBP-3 모두 태아의 성장에 중요한 역할을 하며, 아디포넥틴은 인슐린, IGF-I 축과는 다른 기전으로 태아의 성장을 조절한다고 생각할 수 있었다. IGF-I은 남아에서보다 여아에서 더 높은 수치를 보여서 IGF-I의 성별간의 차이가 자궁 내에서도 존재하였다. 생후 1개월 동안의 성장에 다른 호르몬보다 IGF-I 이 더 중요한 역할을 한다는 사실을 알 수 있었다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제23권4호
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• pp.366-376
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• 2020

Purpose: To assess the association between birth weight and the development of functional gastrointestinal disorders (FGIDs) in the first year of life. Methods: This is a secondary analysis of a prospective cohort multicenter study including neonates, consecutively enrolled at birth, and followed up for one year. At birth all infants were classified by birth weight as extremely low (ELBW), very low, or low when <1,000, <1,500, and <2,500 g, respectively, and by birth weight for gestational age as appropriate (AGA, weight in the 10-90th percentile), small (SGA, weight <10th percentile), and large (LGA, weight >90th percentile) for gestational age. FGIDs were classified according to the Rome III criteria and assessed at 1, 3, 6, and 12 months of life. Results: Among 1,152 newborns enrolled, 934 (81.1%) completed the study: 302 (32.3%) were preterm, 35 (3.7%) were ELBW, 104 (11.1%) were SGA, 782 (83.7%) were AGA, and 48 (5.1%) were LGA infants. Overall, throughout the first year of life, 718 (76.9%) reported at least one FGID. The proportion of infants presenting with at least one FGID was significantly higher in ELBW (97%) compared to LBW (74%) (p=0.01) and in LGA (85.4%) and SGA (85.6%) compared to AGA (75.2%) (p=0.0001). On multivariate analysis, SGA was significantly associated with infantile colic. Conclusion: We observed an increased risk of FGIDs in ELBW, SGA, and LGA neonates. Our results suggest that prenatal factors determining birth weight may influence the development of FGIDs in infants. Understanding the role of all potential risk factors may provide new insights and targeted approaches for FGIDs.

• Design & Manufacturing
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• 제10권3호
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• pp.1-7
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• 2016

In the semiconductor industry the memory and chip were developed to high density memory and high performance chip, so circuit design was also high integrated and the test bed was needed to be thin and fine pitch socket. LGA(Land Grid Array) IC socket with thin wall thickness was designed to satisfy this requirement. The LGA IC socket plastic part was manufacture by injection molding process, it was needed accuracy, stiffness and suit resin with high flowability. After injection molding process the side gates were needed to remove for further assembly process. ln this study, the cold press cutting process was applied to remove the gates. For design of punch and die, the cold press cutting analysis was implemented by$DEFORM-2D^{TM}$ ln consideration of the simulation results, an adequate punch and die was designed and made for the cutting unit. In order to verify the performance of cutting process, the roughness of cutting section of the part was measured and was satisfied in requirement.

• Design & Manufacturing
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• 제10권2호
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• pp.50-54
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• 2016

In the semiconductor industry the final products were checked for several environments before sell the products. The burning test of memory and chip was implemented in reliability for all of parts. The memory and chip were developed to high density memory and high performance chip, so circuit design was also high integrated and the test bed was needed to be thin and fine pitch socket. LGA(Land Grid Array) IC socket with thin wall thickness was designed to satisfy this requirement. The LGA IC socket plastic part was manufacture by injection molding process, it was needed accuracy, stiffness and suit resin with high flowability. In this study, injection molding process analysis was executed for 2 and 4 cavities moldings with runner, gate and sprue. The warpage analysis was also implemented for further gate removal process. Through the analyses the total deformations of the moldings were predicted within maximum 0.05mm deformation. Finally in consideration of these results, 2 and 4 cavities molds were designed and made and tested in injection molding process.