• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.584-589
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• 2007

Polyvinylidene fluoride (PVDF) is a type of electroactive polymer which shows significant shape change when exposed to electric field. PVDF is generally used as a film sensor in non-destructive evaluation (NDE) of materials. In this study, however, its properties relevant to film actuator are considered. Since most of the electromechanical applications that use PVDF and its copolymers as actuators use their piezoelectric properties, only the piezoelectric properties of PVDF are discussed here. These properties depend mainly on the degree of crystallinity of PVDF. Available data from recent research publications are used to simulate the response of a PVDF bimorph beam on the application of electric field, by a commercial finite element analysis package ANSYS. Finally, the factors that affect mechanical behavior of PVDF bimorph beam are discussed.

• Clinical and Experimental Pediatrics
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• 제52권3호
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• pp.283-288
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• 2009

Pneumonia remains the leading cause of mortality in children. Diagnosis depends on a combination of factors, including clinical assessment, radiological and laboratory findings. Although Streptococcus pneumoniae remains the most important cause of childhood bacterial pneumonia, the great majority of cases of community-acquired pneumonia (CAP) are of viral etiology. A new, rapid, and inexpensive test that differentiates viral from bacterial pneumonia is needed to decide empiric antibiotic treatment. Antibiotics effective against the expected bacterial pathogens should be instituted where necessary. The role of emerging pathogens and the effect of pneumococcal resistance and heptavalent conjugate pneumococcal vaccines are to be considered in practice. There are reports supporting the valid and highly efficacious use of penicillin as a first-line drug for treating CAP. This review raises the issue of the overuse of unnecessary antibiotics in viral CAPs and the use of second or third-line antibiotics for non-complicated pneumonias in most clinical settings.

• 대한예방한의학회지
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• 제19권1호
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• pp.95-107
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• 2015

Objective : To use and its affecting factors of patients' outpatient treatment that have single and multiple chronic illnesses Method : We used the 2011 study by the Ministry of Health and Welfare, "Report on Usage and Consumption of Korean Medicine." This report was conducted on outpatients and inpatients that visited Korean traditional medicine, from August 25th, 2011, to September 30th, 2011. Our research was based on 1729 patients with chronic diseases aged 30 and over who received outpatient treatment during the last three months. Results : There were 1365 patients with non-complex chronic diseases, while there were 364 patients with complex chronis diseases. Patients had 1 - 8 chronic diseases, and the average number (standard deviation) was 1.26 (0.59). There were statistically significant differences by sex(P<0.0001), age(p=0.0045), marriage (p=0.0060), education level(p<0.0001), income level(P=0.0063), and types of health insurance(p=0.0023). The diseases most common among patients with non-complex chronic diseases were: low back pain, arthritis, gastrointestinal disorder, frozen shoulder, side effects from motor accidents, high blood pressure, fracture, stroke, diabetes, cancer, atopic dermatitis, and asthma. The diseases most common among patients with non-complex chronic diseases were: arthritis+low back pain, low back pain+gastrointestinal disorder, low back pain+side effects from motor accidents, low back pain+frozen shoulder, arthritis+gastrointestinal disease, gastrointestinal disease+frozen shoulder, arthritis+low back pain+gastrointestinal disease, high blood pressure+arthritis, arthritis+low back pain+frozen shoulder, arthritis+fracture, and arthritis+side effects from motor accidents. There were statistically significant differences among the usage of medical clinics by: frequently used clinic (p<0.0001), number of treatment (p<0.0001), the cost of outpatient treatment (p=0.0073), the satisfaction rate (p=0.0171), whether the clinic is the preferred clinic (p=0.0040). In model 1, men than women, people who had local benefits instead of type 1 medical aid, and patients with complex chronic diseases were more likely to use Korean medical clinics. In model 2, men than women, people who had local benefits than people with types 1 and 2 medical aids, people who went to pharmacies and Korean medicine pharmacies than people who went to hospitals, people who went to get treatment 1-10 times than people who visited 11-20 times and more than 41 times, and people who spent less than ten thousand Korean won than people who spent 1 to 2 million Korean won, and people without complex chronic diseases were more likely to use Korean medical treatment. Conclusion : There were differences in sociodemographic characteristics and the usage of medical clinics between patients with non-complex chronic diseases and patients with complex chronic diseases. Among patients with complex chronic diseases, women, patients with types 1 and 2 medical aid, patients who used Korean medical clinics, patients who were treated 11-20 times and more than 41 times, and patients who spent 1 million to 2 million Korean won on outpatient treatment used less treatment than patients with non-complex chronic diseases. However, patients with complex chronic diseases used pharmacies and Korean medicine pharmacies more.

• 한국대기환경학회지
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• 제33권2호
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• pp.77-86
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• 2017

Globally, use of affordable fuels such as briquettes, woods and wood pellets has increased. Organic pollutants emitted from non-point sources using solid fuels may have contributed to air pollution in urban environment. In this study, we utilized simulated incinerator proposed by U.S. EPA and investigated concentrations of PM, $PM_{10}$, $PM_{2.5}$, OC/EC, CO, $SO_x$, $NO_x$, VOCs and PAHs emitted while cooking meat and fish using briquettes, woods and wood pellets, and developed emission factors. As a result, wood combustion produced more air pollutants than the others. Particulate matter emission factors for woods and wood pellets were 13.54 g/kg and 9.15 g/kg, respectively. Total VOCs emission factors for briquettes, woods and wood pellets were 36.12mg/kg, 46.13mg/kg and 18.26mg/kg, respectively. Additionally, total PAHs emission factors for briquette, woods and wood pellets were 0.44 mg/kg, 18.84mg/kg and 101.62mg/kg, respectively.

• 수면정신생리
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• 제7권1호
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• pp.5-9
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• 2000

Several nonpharmacological treatment methods of insomnia and their effects were reviewed. A long-term use of most hypnotics may produce tolerance, dependence, cognitive and psychomotor impairments at daytime, shallow sleep, and rebound insomnia on drug withdrawal. To reduce hypnotic abuse, nonpharmacological strategies have been developed to correct disordered behavioral and cognitive factors. These treatments aim at modifying maladaptive sleep habits, lowering physiological and cognitive arousal levels, and correcting dysfuctional beliefs and attitudes about sleep. These non-pharmacological or cognitive behavior treatments include stimulus control, sleep restriction, relaxation training, sleep hygiene education, cognitive therapy, and light therapy. Among them the stimulus control therapy has been demonstrated most effective as a single treatment or in combination with other treatments. Through nonpharmacological treatments, sleep latency was most significantly reduced and wake time after sleep onset was also reduced. About 50% of insomniacs reported clinical improvements in terms of nearly normalized sleep latency, awakening time, sleep efficiency, and reduction of hypnotic use. Compared to the hypnotic therapy, nonpharmacological treatments are more cost-effective and more readily accepted by patients, and their effects last longer.

• 대한가정학회지
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• 제39권10호
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• pp.29-37
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• 2001

The purpose of this study is to investigate the preference and the use of the bedclothes. The data were obtained from market research of 12 department stores which were located in Seoul, Daegu and Busan, and from questionnaires completed by 356 women in Daegu area whose age was 20 years and older. The SPSS package was used for data analysis which includes frequency, percentage, $X^2$test, ANOVA, and Scheffe test. Cotton was the most popular fiber for coverings and fillings. Color preference was in the order of pastel, non-chromatic, vivid, and white color and pattern preference was in order of floral, check, and stripe pattern. Practicality, color and fabric were the most important factors and price was the most unsatisfied factor when bedclothes were purchased. Also, information for bedclothes was obtained mainly through internet shopping, home shopping or catalog shopping.

• 대한토목학회논문집
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• 제43권3호
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• pp.353-362
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• 2023

본 연구에서는 수원시에 도입되었던 dockless형 공유자전거인 모바이크의 이용자 빅데이터에 대한 이용현황 및 이용특성을 분석하고, 이에 대한 다중회귀분석을 수행하여 dockless형 공유자전거 이용수요 영향요인을 규명하였다. 분석을 위해 2019년 수원시의 dockless형 공유자전거 이용 데이터를 구득하였고, 이를 동별로 정리하였다. 동별로 선정된 영향요인의 특성을 분석한 결과, 자전거 이용수요가 많은 지역 또는 인접한 지역의 자전거도로 연장이 큰 것으로 나타났고, 10-30대 인구 수가 많은 것으로 나타났다. 또한, 자전거도로 정비율이 높고 택지지구 인근의 대규모 주거시설과 상업시설이 밀집된 지역과 인접 지역을 중심으로 공유자전거 이용이 많은 것으로 분석되었다. 다중회귀분석 모델 분석 결과, 자전거 겸용도로(비분리), 동별 10-30대 인구, 철도역 수, 상업시설 수, 산업시설 수, 초·중·고 학교 수가 dockless형 공유자전거 이용수요에 미치는 영향이 유효한 것으로 확인되었다. Dockless형 공유자전거 이용수요에 영향을 미치는 요인을 파악하여 시민이 dockless형 공유자전거를 이용하고 싶어 하는 환경을 조성할 수 있을 것으로 기대된다. 또한, 연구 결과는 향후 dockless형 공유자전거 이용 활성화를 위한 정책적 자료에 기여될 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권4호
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• pp.462-470
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• 2012

The availability and efficient use of the feed resources in India are the primary drivers to maximize productivity of Indian livestock. Feed security is vital to the livestock management, extent of use, conservation and productivity enhancement. Assessment and forecasting of livestock feed resources are most important for effective planning and policy making. In the present study, 40 years of data on crop production, land use pattern, rainfall, its deviation from normal, area under crop and yield of crop were collected and modeled to forecast the likely production of feed resources for the next 20 years. The higher order auto-regressive (AR) models were used to develop efficient forecasting models. Use of climatic variables (actual rainfall and its deviation from normal) in combination with non-climatic factors like area under each crop, yield of crop, lag period etc., increased the efficiency of forecasting models. From the best fitting models, the current total dry matter (DM) availability in India was estimated to be 510.6 million tonnes (mt) comprising of 47.2 mt from concentrates, 319.6 mt from crop residues and 143.8 mt from greens. The availability of DM from dry fodder, green fodder and concentrates is forecasted at 409.4, 135.6 and 61.2 mt, respectively, for 2030.

• 대한가정학회지
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• 제43권11호
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• pp.1-15
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• 2005

The purpose of this study was to investigate the attitude, knowledge and need for educational contents about credit cards according to credit card use, and to examine the status of credit card use and the factors affecting credit card management behaviors of college students. The data were collected from 481 college students in Busan and Kyungnam areas by a self-administered questionnaire. Frequencies, Cronbach's alpha, factor analysis, t-test, ${\chi}^2$ analysis, Pearson's correlation analysis and regression analyses were conducted by SPSS WINDOWS. The results from this study were as follows. First, there were no significant differences between the credit card user group and the non-user group in the means of their altitude and knowledge towards credit cards. The mean of each category of the need for educational contents was high in both groups. Second, respondents of the credit card user group answered that they used credit cards whenever necessary, using them to purchase mostly clothing, shoes, and books. Third, credit card management behaviors were influenced by the allowance amount, experience of consumer education related to credit cards, number of total credit cards, attitude towards credit cards, knowledge about credit cards, frequency of credit card use, terms of credit card use and father's occupation. These results suggest that consumer education should be conducted for the credit card management behaviors of college students.

• 가족자원경영과 정책
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• 제15권2호
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• pp.103-128
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• 2011

The purpose of this study is to analyze the family sharing time of housework and to examine the sharing time with family is influenced by socio-demographic variables. The Time Use Survey data collected by Korean National Statistical Office in 2009 is used. Among the total sample of 21,000 individuals, 9,179 samples who are married, aged from 20 to 59 years old and non-farmers are selected for analysis. The statistical methods are frequency, percentage, crosstabulation, t-test, and regression analysis. The following is a summary of the major findings. First, comparison of men and women shows women spend more time on housework than men do. But sharing housework time with family for men increase on Sunday. Performer average is almost same in men and women. Secondly, the family sharing time on housework is longer on Sunday. It is due to increase of men's family sharing time. It means that men's time substitute for women's housework. Thirdly, the influencing factors on family sharing housework are gender, age, education, presence of spouses, monthly income, dual earner status, weekly working hours, gender role atittude and presence of preschoolers. Family sharing housework is not only household labor but also family pleasure time. It means family policy should focus on making family time for workers fundamentally. And family policy needs to make a system of educational program for work-family balance.