• Structural Engineering and Mechanics
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• 제82권6호
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• pp.785-799
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• 2022

The effect of earthquakes in earthquake resistant structure design stages is influenced by the highest ground acceleration value, which is generally a strength-based approach in seismic codes. In this context, an energy-oriented approach can be suggested as an alternative to evaluate structure demands. Contrary to the strength-based approach, the strength and displacement demands of the structure cannot be evaluated separately, but can be evaluated together. In addition, in the energy-oriented approach, not only the maximum effects of earthquakes are taken into account, but also the duration of the earthquake. In this respect, it can be said that the use of energy-oriented earthquake parameters is a more rational approach besides being an alternative. In this study, strength and energy-oriented approaches of earthquake parameters of 11 different periods of single degree of freedom systems were evaluated over 28 different earthquake situations. The energy spectra intended to be an alternative to the traditional acceleration spectra were created using the acceleration parameter equivalent to the input energy. Two new energy parameters, which take into account the effective duration of the earthquake, are proposed, and the relationship between the strength-oriented spectral acceleration parameters and the energy parameters used in the literature is examined by correlation study. According to the results obtained, it has been seen that energy oriented earthquake parameters, which give close values in similar period situations, will be a good alternative to strength oriented earthquake parameters. It was observed that the energy parameters were affected by the effective duration of the earthquake, unlike the strength-based parameters. It has been revealed that the newly proposed energy parameters considering the effective duration give good correlations. Finally, it was concluded that the energy parameters can be used in the design, and the newly proposed effective energy parameters can shorten the analysis durations.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7509-7515
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• 2013

To assess the risk of cancers associated with sleep duration using meta-analysis of published cohort studies, we performed a comprehensive search using PubMed, Embase and Web of Science through October 2013. We combined hazard ratios (HRs) from individual studies using meta-analysis approaches. A random effect dose-response analysis was used to evaluate the relationship between sleep duration and cancer risk. Subgroup analyses and sensitivity analyses were also performed. Publication bias was evaluated using Funnel plots and Begg's test. A total of 13 cohorts from 12 studies were included in this meta-analysis, which included 723, 337 participants with 15, 156 reported cancer outcomes during a follow-up period ranging from 7.5 to 22 years. The pooled adjusted HRs were 1.06 (95% CI: 0.92, 1.23; P for heterogeneity =0.003) for short sleep duration, 0.91 (95% CI: 0.78, 1.07; P for heterogeneity <0.0001) for long sleep duration. In subgroup analyses stratified by cancer type, long duration of sleep showed an inverse relation with hormone-related cancer (HR=0.79; 95% CI: 0.65, 0.97; P for heterogeneity =0.009) and a greater risk of colorectal cancer (HR=1.29; 95% CI: 1.09, 1.52; P for heterogeneity =0.346). Further meta-analysis on dose-response relationships showed that the relative risks of cancer were 1.00 (95% CI: 0.99, 1.01; P for linear trend=0.9151) for one hour of sleep increment per day, and 1.00 (95% CI: 0.98, 1.01; P for linear trend=0.7749) for one hour of sleep increment per night. No significant dose-response relationship between sleep duration and cancer was found on non-linearity testing (P=0.5053). Our meta-analysis suggests a positive association between long sleep duration and colorectal cancer, and an inverse association with incidence of hormone related cancers like those in the breast. Studies with larger sample size, longer follow-up times, more cancer types and detailed measure of sleep duration are warranted to confirm these results.

• 수면정신생리
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• 제16권2호
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• pp.85-90
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• 2009

목 적: 수면문제와 자살위험의 증가의 연관성에 대한 관심이 증가하고 있다. 자살사고를 보이는 환자에서 수면문제의 호소는 매우 흔한 일이다. 비록 수면문제가 정신과적 질환에 매우 흔한 증상 중 하나이지만, 불면증, 수면과다증, 악몽등과 같은 수면문제는 특히 자살위험이 높은 환자에서 흔함이 보고되었다. 본 연구에서는 수면시간과 자살사고의 연관성에 대해 조사해 보고자 하였다. 방 법: 인천지역에 거주하는 주민 1,000명(남자:여자=500:500명, 평균연령=39.6${\pm}$11.6세, 연령범위=20~77세)을 대상으로 하였다. 전체 대상군의 사회인구학적 정보를 조사하였고, 지난 한달 동안의 수면시간 및 수면습관, Beck 자살사고 척도(Beck Suicide Intent scale;이하 BSI), 우울증 척도(Center for Epidemiologic Study-Depression;이하 CES-D), 분노감 척도(Spielberger State-Trait Anger Expression Inventory;이하 STAXI), 충동성 척도(Barratt Impulsiveness Scale;이하 BIS), 아침형-저녁형척도(Morningness-Eveningness Scale;이하 MES)로 구성된 설문지를 완성하도록 하였다. 결 과: 전체 대상군에서의 상관관계분석에서 나이와 성별을 보정한 후, BSI점수는 CES-D, STAXI, BIS와 유의한양의 상관관계를 보였으며(각각 $r_P$=0.251; p<0.001, $r_P$=0.352: p<0.001, $r_P$=0.175; p<0.001), MES와는 유의한 음의 상관관계를 보였다($r_P$=-0.066; p=0.037). 수면시간은 BSI점수와는 유의한 상관관계를 보이지 않았다($r_P$=-0.054; p=0.091). 전체 대상군에서 BSI를 종속변수로 하고, 나이, 성별, 가족내 소득, 정신질환의 가족력, 교육, 결혼상태, 종교의 사회인구학적 변수와 CES-D 점수, STAXI 점수, BIS 점수, MES 점수, 6시간 이하나 10시간 이상의 수면시간을 갖는 군을 독립변수로 선형회귀분석을 시행하였다. 정신질환의 가족력, CES-D 점수, STAXI 점수, 6시간 이하나 10시간 이상의 수면시간이 유의하게 자살사고 점수를 예측하였다(F=17.837, adjusted $R^2$=0.166, 각각 p=0.003, p<0.001, p<0.001, p=0.003). 경도 이상의 우울증상이 있는 군으로 한정하였을 때에도, 같은 변인들이 자살사고를 유의하게 예측하였는데, 이 모형이 가지는 설명력은 우울한 집단에서 더 높았다(F=9.920, adjusted $R^2$=0.298). 결 론: 본 연구결과는 주관적 보고에 기초한 6시간 이하의 짧은 수면시간뿐 아니라 10시간 이상의 긴 수면시간도 자살사고와 유의한 연관성이 있음을 제시한다.

• 한국실내디자인학회논문집
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• 제24권4호
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• pp.51-60
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• 2015

This study aims to establish the foundation for a simultaneity research, draw the potential through Bergson's simultaneity, and explore a space with the possibility of a continued change, focusing on the simultaneous process, in which physical mobility and consciousness of space last together. First, this study was focused on understanding Bergson's simultaneity, on the basis of the perspective that space needs to have more active, dynamic mobility. For understanding Bergson's simultaneity, the understanding of Bergson's duration conception, memory and perception was preceded. After that, the characteristics of simultaneity were extracted from the concepts of duration, change, memory and perception and its characteristics, which are connected to space, were analyzed. As a result, the study on simultaneity that was intensively analyzed, based on diverse cases, re-awakened the basis of value or thought, which we must aim at, in space design of the present time. This shows the possibility of another creative form that can be found in spaces of the present time and serves as the foundation to discover an essential and potential value of space in space design. Moreover, the combination of space with science, humanities, art and digital media technology demonstrated once again that there is a good possibility of approaching non-representational space that is pursued today and it is anticipated that using Bergson's simultaneity as a medium for spatial combination in their relationship would help in drawing deeper internal meaning and potential of space.

• Journal of Nutrition and Health
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• 제29권9호
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• pp.1003-1012
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• 1996

We examined the relationship among riboflavin intake, work activity, erythrocyte glutathione reductase activity coefficient(EGR AC)and urinary riboflavin excretion. We also attempted to determine factors affecting seasonal riboflavin status of rural women. All information about nutrient intake, work activity and riboflavin biochemical status was repeatly collected in three seasons ; farming season(June), harvest season(October), nonfarming season(February). EGR AC was negatively correlated with riboflavin intake(P<0.005) and positively correlated with the duration(min) of farming activity(P<0.005) and the percentage of lean body mass(LBM) (%) representing long term physical activity(P<0.05) in harvestseason. Urinary riboflavin excretion was positively correlated with the ratio of riboflavin intake to 1,000kcal of energy expenditure (P<0.05) in farming season and negatively correlated with the duration(min) of farming activity (P<0.05) and crude nitrogen balance(P<0.005) in harvest season. It appeared that EGR AC seems to increase and urinary riboflavin excretion seems to decrease as work activity increase. Therefore work activity would be expected to deteriorate riboflavin status. Multiple regression analysis of variables showed that in general EGR AC was affected by riboflavin and energy intakes, energy expenditure, energy balance, the duration(min) of farming activity, LBM (%). Urinary riboflavin excretion was affected by riboflavin and protein intakes, LBM(kg) and crude nitrogen balance. Crude nitrogen balance affected urinary riboflavin excretion in all seasons. The result indicated that work activity as well as nutrient intake seemed to affect riboflavin status, especially EGR AC was affected preferentially be work activity in all seasons.

• 지역사회간호학회지
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• 제29권1호
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• pp.76-86
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• 2018

Purpose: The purpose of study was to examine the relationship between obesity and its associated factors (psychiatric symptom, duration of illness, type of medication, physical activity, dietary habits, depressive symptom, and stress) in patients with chronic mental illness registered to community mental health welfare centers. Methods: This was a cross-sectional correlation study using a convenience sampling. A total of 392 participants were recruited from community mental health welfare centers. The obtained data were analyzed using binary and multinomial logistic regression. Results: Atypical antipsychotic medication, duration of illness, dietary habits (overeating, and drinking instant coffee) were significantly contributed variables into body mass index (BMI) obesity. Atypical antipsychotic medication and instant coffee were significantly related to abdominal obesity. Conclusion: These results emphasized the needs of tailored obesity-preventive management for the community-dwelling patients with chronic mental illness, topically focusing on the administration of atypical antipsychotic medication, duration of illness, and dietary habits.

• 대한의생명과학회지
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• 제10권4호
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• pp.453-457
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• 2004

The welders and car painters are frequently exposed to heavy metals such as lead, zinc, cadmium and chromium, and those are a major source of heavy metal poisoning. This study was carried out to investigate the relationship of the heavy metal level in blood by age, working duration, and smoking status among 105 industrial workers and 88 general people in Gyeongnam province from October 2003 to October 2004. The heavy metal level in blood was analyzed by atomic absorption spectrophotometer. Mean blood lead level in exposed group and control group was 8.40±4.67μl/dl, 1.82±1.35μl/dl, respectively. Mean blood zinc level in exposed group and control group was 9.43±5.38 ㎍/ml, 2.89±1.79㎍/ml, respectively. Mean blood cadmium level in Exposed group and control group was 1.53±1.05μl/dl, 0.60±0.49 μl/dl, respectively. Mean blood chromium level in exposed group and control group was 0.89±0.76μl/dl, 0.68±0.63μl/dl, respectively. Lead, zinc, cadmium and chromium level in blood of exposed group was significantly higher than that of control group. In the comparison of smoking status, lead, zinc and cadmium level of smoker's was significantly higher than that of non-smoker's. Comparison of heavy metal level by age, lead, zinc, cadmium level in 40's, 50's (exposed group) in blood significantly higher than that of 20's, 30's. In exposed group, working duration has no significant difference. In conclusion, smoking was the most hazardous factor to elevate in blood heavy metal levels.

• Journal of Preventive Medicine and Public Health
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• 제21권2호
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• pp.365-373
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• 1988

Information on work stress and mental health status of industrial workers was required for optimum staffing and health care management. This study dealt with the relationship between mental health status examined by PSI(psychiatric symptom index) and socio-demographic variables. Especially this study attempted to find relevant determinants of the stress and mental health through multiple stepwise regression analysis based on data obtained from 687 occupational workers. The findings of this study were as follows; Mean scores of symptom dimension were higher in youth, female, more educated, unmarried and divorced, and workers in the noisy condition and short duration in job. And it showed high scores in long duration in job for anxiety; college educated for anger; unmarried for cognitive disturbance. The factors affecting the mean scores of psychiatric symptom index were varied according to the types of symptom: age, sex and duration in job for anxiety; age, sex, living with parent, education and marital status for anger; sex and marital status for depression; noisy condition and sex for cognitive disorder.

• 디지털산업정보학회논문지
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• 제12권4호
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• pp.163-169
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• 2016

This study is to analyze factors affecting a growth of online community with perspectives of social network. Particularly this study tries to explore structural phenomenon built by interactions between users in a certain of free board belonging to the online community, in which focuses on one's writing a comments responding on those of others. With using SNA(Social Network Analysis), the social network data calculated from users' interaction shown as their comments were collected to draw out each individual's centrality value representing the structure of the online community and also we estimated duration time and the number of each comments as a proxy variable representing growth of the online community. And then cause-and-effect relationship between individual's centrality value and the duration time and the number of each comment were analyzed. As a result of the analysis, Core-Periphery, Centralization and Reciprocity have significant effects on the duration time and the number of each comment, therefore those significant values representing online structure will give an implication to manage, to promote the online community, to forecast its evolution path and to build critical policies.

• 한국물환경학회지
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• 제29권1호
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• pp.55-65
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• 2013

It is very difficult to apply stream flow data directly to the management of Total Maximum Daily Loads because there are some differences between the unit watershed and the stream flow monitoring network in their characteristics such as monitoring locations and its intervals. Flow duration curve can be developed by linking the daily flow data of stream monitoring network to 8 day interval flow data of the unit watershed. This study investigated the current operating conditions of the stream flow monitoring network and the flow relationships between the unit watershed and the stream flow monitoring network. Criteria such as missing and zero value data, and correlation coefficients were applied to select the stream flow reference sites. The reference sites were selected in 112 areas out of 142 unit watersheds in 4 river basins, where the stream flow observations were carried out in relatively normal operating conditions. These reference sites could be utilized in various ways such as flow variation analysis, flow duration curve development and so on for the management of Total Maximum Daily Loads.