• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2009년도 추계학술발표대회
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• pp.547-548
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• 2009

The development of USN(Ubiquitous Sensor Network) technology is creating numerous application areas. Although a network configuration with fixed sensors was the norm in the past, the coexistence of mobile and fixed sensor nodes is a new trend. Fixed sensor networks focused on the energy efficiency of nodes, but the latest studies consider guaranteeing the mobility of nodes and maintaining their connectivity, while remaining energy efficient at the same time. This paper proposes a routing protocol for a mobile ad-hoc sensor network that improves the mobility, connectivity and energy efficiency of nodes while allowing for the management and maintenance of a large number of nodes even in a complex communication environment where mobile and fixed nodes coexist. An algorithm for multi-hop multi-paths, a technique for topology reconfiguration by node movement prediction and vibration sensors, path setting for a large number of nodes, and efficient data transfer technology have been introduced to implement the modified LEAHC-AOMDV protocol. Furthermore, the excellence of this protocol was verified through a comparative experiment with the conventional LEACH protocol.

• 한국항행학회논문지
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• 제25권6호
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• pp.543-549
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• 2021

본 논문에서는 불확실성의 크기가 유한한 파라미터를 갖는 스트랩다운 관성항법시스템에 대한 강인한 전달정렬 기법을 제안하였다. 크레인 공간을 이용하면 에너지가 유한한 불확실성을 갖는 강인한 필터는 일반적인 칼만필터와 동일한 구조를 갖게 된다. 단지 측정 행렬과 측정 잡음의 공분산값을 수정하면 된다. 본 논문에서 제안한 강인한 전달정렬 기법의 성능을 분석하기 위해서 항체가 고기동 운항을 하면서 측정치에 시간 지연이 발생하는 경우를 가정하여 시뮬레이션을 수행하였고 제안한 기법의 강인성을 검증하였다.

• 동의생리병리학회지
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• 제27권3호
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• pp.318-326
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• 2013

This study was performed to investigate relationship between each pattern identification and heart rate variability(HRV) indices. We analyzed 201 subjects who participated in stroke check up. We classified the subjects into four groups of pattern identifications; Fire-Heat pattern(FH), Yin Deficiency pattern(YD), Qi Deficiency pattern(QD) and Dampness-Phlegm pattern(DP) that based on Korean Standard Pattern Identifications for Stroke-III. We investigated significance of HRV indices between each pattern identification and heart rate variability indices. The total number of the subject group was 201, whereas the groups were divided into four groups; Fire-Heat pattern group(n=47), Yin Deficiency pattern(n=65), Qi Deficiency pattern(n=33), and Dampness-Phlegm pattern(n=56). SDNN, TP, Ln(TP), VLF, Ln(VLF), LF, Ln(LF) and HF were significantly higher in the Fire-Heat pattern(FH) group than other groups of pattern identifications, but there was no differences among the Yin Deficiency group, the Qi Deficiency group and the Dampness-Phlegm group. Ln(HF), LF(NORM), HF(NORM) and LF/HF ratio were significantly higher in the Fire-Heat group than in the Qi Deficiency group. However, there was no significant differences among the Dampness-Phlegm group, the Yin Deficiency group, Fire-Heat group and the Qi Deficiency group. Through this study, we found out some significant relationships between each pattern identification group and HRV indices. The result of this study demonstrates that sympathetic nerve was more active in the Fire-Heat group than other groups.

• 정신신체의학
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• 제6권2호
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• pp.155-175
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• 1998

The purpose of this study was to test a reliability and validity of the Korean version of Eating Attitudes Test-26(KEAT-26). Using multi-stage sampling, we finally got 3,496 subjects(1422 males and 2074 females) who were available for analysis from target 4,400 Korean adults over 18 in the nationwide areas of9 kus, 10 middle or small cities, and 17 kuns. We tried to make T score norm of the KEAT-26 as a cutoff score and STEN score norm as a index of severity for disordered eating behaviors. For the male group, Cronhach's internal consistency was .83 and Spearman-Brown split half correlation coefficiency was .75. For the female group, each of them was .81 and .75, and .81, .75 for the grand total group respectively. Validity test was performed by construct validation analysis. By a iterated principal axis factoring, 4 factors were extracted. There were some differences in the factors of the KEAT-26 by sex. In the male group, factor I was 'self-control of eating and bulimic symptom', factor II was 'food preoccupation and dieting', factor III was 'preoccupation with being thinner', factor N was 'avoidance of sweet foods'. In contrast with the male group, factor I was 'self-control of eating and bulimic symptom', factor II was 'preoccupation with being thinner', factor III was 'food preoccupation' and factor N was 'dieting' in the female group. We used T score 65 as a cutoff score. T score 65 corresponded to raw score 19 in the male group, 22 in the female group and 21 in the grand total group. Severity of disordered eating behaviors was measured by a STEN score. In the male group, each of the score range of 0-10, 11-14, 15-18, 19-22 and over 23 represented the degree of none, subclinical, manifest, moderate and severe severity respectively. Each of the score range of 0-13, 14-17, 18-21, 22-26 and over 27 in the female group, and the score range of 0-12, 13-16, 17-20, 21-25 and over 26 in the grand total group also represented the same degree of severity as like in the male group. These results support that KEAT-26 is a reliable and valid scale for evaluating disordered eating behaviors and eating problems.

• 한국인구학
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• 제33권1호
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• pp.75-101
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• 2010

우리나라는 출산율 저하의 심각한 문제에 직면해 있고, 그 원인 중의 하나는 결혼 적령기 연령층의 결혼이 지연되는 현상과 연관된다. 최근의 미혼 비율 증가 경향과 관련하여, 이 연구의 기본목적은 교육수준, 취업 여부, 직업 같은 경제적 자원이 결혼 가능성 혹은 결혼 연기에 미친 영향이 성별로 어떻게 다른지를 분석하는 것이다. 또한 1995년, 2000년, 2005년 세 시점의 자료를 분석하여 외환위기 전후 경제적 자원의 영향력 변화를 비교하면서 결혼적령기 연령규범 영향력의 변화도 함께 살펴보고자 한다. 이 연구는 1995년, 2000년, 2005년 인구주택총조사(Census) 2% 원 자료에서 추출한 만20세에서 만44세까지의 남녀를 분석대상으로 하였으며 총 표본수는 약 110만명이다. 연도별, 성별로 경제적 자원이 결혼여부에 미치는 영향을 분석하기 위해 이항 로지스틱(logistic) 회귀분석을 사용하였다. 본 연구는 결혼 가능성에 대한 경제적 자원의 영향을 분석하면서 그 영향이 성별에 따라 다르다는 전통적 가설을 재확인할 수 있었고 경제위기 이후 남성에게서 경제적 자원의 질적인 측면이 중요해지고 있다는 점과 여성에게서 경제적 자원이 결혼가능성에 미치는 부정적인 영향이 다소 완화되는 추세를 보인다는 점을 발견한 학술적 기여를 하였다. 결혼적령기 연령규범은 적어도 여성들의 경우에는 최근으로 올수록 약화되는 조짐을 보이고 있다고 해석할 수 있다. 연구의 전반적인 발견은 우리사회에서 경제위기 이후의 경제적 양극화 경향이 결혼시장에서도 양극화 추세로 나타나는 조짐이 있다는 것을 시사하는 것이라고 볼 수 있다.

• 대한한방내과학회지
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• 제33권3호
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• pp.284-297
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• 2012

Objectives : This study was performed to investigate characteristic indice of heart rate variability (HRV) according to presence of metabolic syndrome (MS), pattern identification. Methods : We analyzed 167 subjects who participated in a stroke check-up. We classified the subjects into two groups as MS (n=48) and non-MS (n=119) based on NCEP ATP III. First, we investigated pattern identification of all subjects based on Korean Standard Pattern Identifications for Stroke-III. Second, we surveyed significance of HRV indices between MS and non-MS groups. Third, we investigated significance of HRV indices between classified DP of MS and classified DP of non-MS. Fourth, we investigated significance of HRV indices between classified DP of MS and non-MS. Fifth, we investigated significance between components of MS and HRV indices. Results : 1. SDNN, RMS-SD, HF, Ln(HF), and HF (NORM) were significantly lower in the MS than non-MS group. LN (TP), LF/HF were significantly higher in the MS than non-MS. 2. Ln (HF), Ln (TP), and LF/HF were statistically significant in the classified DP of MS group. 3. RMS-SD, and Ln (HF) were significantly lower in the abdominal obesity group than in the non-abdominal obesity group. SDNN, RMS-SD, TP, Ln (TP), VLF, Ln (VLF), and Ln (LF) were significantly lower in the hypertension group than in the non-hypertension group. RMS-SD was significantly lower in the diabetes group than in the non-diabetes group. Mean HRT,LF/HF were significantly higher in the hypertriglyceridemia than non-hypertriglyceridemia group, but Ln (HF), RMS-SD, and HF (NORM) were significantly lower in the hypertriglyceridemia than non-hypertriglyceridemia group. Conclusions : We found a few significant relationships between classified DP of MS and HRV indices. The resluts demonstrate that MS has potentially negative effects on the cardiovascular system, and these effects could be detected by HRV.

• 디지털융복합연구
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• 제14권4호
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• pp.363-370
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• 2016

소음은 원하지 않는 소리로서 소음의 노출은 스트레스와 난청의 원인이 된다. 본 연구에서는 치기공과 학생의 치과기공 소음 노출에 의하여 스트레스와 순음청력에 미치는 영향을 파악하기 위하여 심박변이도와, 공기전도검사와 골전도검사를 실시하였다. 치기공과 학생의 나이, 키와 체중은 대조군과 유사한 결과를 나타냈다. 스트레스의 저항도를 나타내는 심박 표준편차와 부교감신경의 활성과 관련 있는 norm HF는 유의적으로 감소하였으며, 심박수, 교감신경의 지표인 norm LF, 교감신경과 부교감신경의 비율은 유의적으로 증가하였다. 공기전도검사 결과 치기공과 학생의 오른쪽 귀의 125, 250, 500, 1000, 2000, 3000, 4000, 6000 Hz와 왼쪽 귀의 125, 250, 500, 1000, 2000 Hz에서 역치와 골전도검사 결과 오른쪽과 왼쪽 모두 250, 500, 1000, 2000, 4000 Hz에서 역치가 유의적으로 증가하였다. 또한, 순음청력검사 결과를 4분법을 이용하여 어음영역의 평균을 비교한 결과 치기공학과 학생에서의 역치가 모두 유의적인 증가를 보였다. 이와 같은 결과를 종합해 보면, 치기공학과 학생들에게 노출된 치과기공 소음에 의해서도 스트레스의 증가와 청력소실이 유발될 수 있으므로 적절한 예방책을 찾아야 할 것이다.

• 대한지역사회영양학회지
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• 제24권5호
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• pp.374-383
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• 2019

Objectives: This study analyzed Japanese consumers on their sauce consumption, and assessed the relationship between consumer innovativeness and consumption behavior for new sauce products. Methods: The survey was completed by local consumers visiting Korean restaurants in Osaka, Japan, in September 2018. The demographic characteristics, consumption of sauce, consumer innovativeness, and factors of theory of planned behavior were evaluated. Totally, 150 collected data were analyzed using the IBM SPSS Statistics 25.0 Program (IBM SPSS INC, Armonk, NY, USA). Results: Results of the survey indicate that Japanese consumers purchase a sauce by considering the taste and food utilization. Sauce purchases were maximum at mega markets and supermarkets. The consumer innovativeness for Japanese consumers was based on 3 factors: 'Purchasing adventurous products (3.51 ± 0.96)', 'Active information seeking (4.36 ± 1.11)', and 'Interactive information seeking (4.33 ± 1.02)', where the tendency of 'Active information seeking' was the highest innovativeness factor. Furthermore, higher values of perceived behavior control (4.68 ± 1.21), attitude (4.66 ± 1.41) and subjective norm (4.39 ± 1.28) were revealed, when assessing for theory of planned behavior factors. Correlating the variables of consumer innovation and factors of planning behavior theory, 'Active information seeking' is a positive attribute for attitude (p<0.016), subjective norm (p<0.001), and perceived behavior control (p<0.002). These 3 factors also had significantly positive effects on purchase intention for new sauce product (p<0.000, p<0.000, and p<0.002, respectively). Attitude was determined to be another very influential variable for purchase intention of a new sauce product (B=0.484, t=6.881). Conclusions: The results of this study determine the consumption patterns of sauce for the Japanese consumer, and the relationship between consumer innovativeness and consumption behavior for Korean traditional sauces. We believe the data generated from this study will help determine a marketing strategy to enter the Japanese market.

• 방사선산업학회지
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• 제10권4호
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• pp.173-179
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• 2016

Coals and coal ashes, raw materials and by-products, in coal-fired power plants contain naturally occurring radioactive materials (NORM). They may give rise to internal exposure to workers due to inhalation of airborne particulates containing radioactive materials. It is necessary to characterize radioactivity concentrations of the materials for assessment of radiation dose to the workers. The objective of the present study was to analyze radioactivity concentrations of coals and by-products at four coal-fired plants in Korea. High purity germanium detector was employed for analysis of uranium series, thorium series, and potassium 40 in the materials. Radioactivity concentrations of $^{226}Ra$, $^{228}Ra$, and $^{40}K$ were $2{\sim}53Bq\;kg^{-1}$, $3{\sim}64Bq\;kg^{-1}$, and $14{\sim}431Bq\;kg^{-1}$ respectively in coal samples. For coal ashes, the radioactivity concentrations were $77{\sim}133Bq\;kg^{-1}$, $77{\sim}105Bq\;kg^{-1}$, and $252{\sim}372Bq\;kg^{-1}$ in fly ash samples and $54{\sim}91Bq\;kg^{-1}$, $46{\sim}83Bq\;kg^{-1}$, and $205{\sim}462Bq\;kg^{-1}$ in bottom ash samples. For flue gas desulfurization (FGD) gypsum, the radioactivity concentrations were $3{\sim}5Bq\;kg^{-1}$, $2{\sim}3Bq\;kg^{-1}$, and $22{\sim}47Bq\;kg^{-1}$. Radioactivity was enhanced in coal ash compared with coal due to combustion of organic matters in the coal. Radioactivity enhancement factors for $^{226}Ra$, $^{228}Ra$, and $^{40}K$ were 2.1~11.3, 2.0~13.1, and 1.4~7.4 for fly ash and 2.0~9.2, 2.0~10.0, 1.9~7.7 for bottom ash. The database established in this study can be used as basic data for internal dose assessment of workers at coal-fired power plants. In addition, the findings can be used as a basic data for development of safety standard and guide of Natural Radiation Safety Management Act.

• 한국전산구조공학회논문집
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• 제35권6호
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• pp.367-374
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• 2022

본 논문에서는 역전파 방법 기반 자동미분법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용하였다. 응력제한조건이 있는 위상최적화문제는 특이점(singularity)과 응력의 국부성(local nature of stress constraint)문제, 그리고 설계 변수에 대한 비선형성의 문제를 포함하고 최적해를 얻기가 매우 힘들다. 특이점 문제를 해결하기 위해서 응력 완화(stress relaxation) 기법을 사용하였고, 응력의 국부성을 해결하기 위해 p-norm을 이용한 전역 응력치를 제한조건에 사용하였다. 설계 변수에 대한 비선 형성을 극복하기 위해 해석적인 방법으로 정확한 설계민감도를 구하는 것이 중요하다. 위상최적설계에서 기존에는 보조변수방법 (adjoint variable method)을 사용하여 빠르고 정확한 설계민감도를 구했지만, 설계민감도를 해석적으로 구해야 하고, 보조평형방정식을 추가로 풀어야 하는 어려움이 있다. 이를 해결하기 위해서 인공신경망에서 최적 가중치(weights)와 편차(biases)를 구할 때 쓰이는 역전파 기법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용하였다. 역전파 기법은 자동미분에 쓰이는 기법으로 목적함수나 제한조건에 대한 설계민감도를 별도의 수식유도 없이 간단하게 구할 수 있는 장점이 있다. 또한, 미분값을 구하는 역전파의 과정이 보조평형방정식을 푸는 것보다 계산시간이 빠르고 해석적 방법으로 구한 설계민감도와 같은 정확도를 보여준다.