• Journal of the military operations research society of Korea
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• v.4 no.1
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• pp.113-123
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• 1978

Consider a series system of two units, named 1 and 2, respectively. Two units are observed at the beginning of discrete time periods t=0,1,2, $cdots$ and classified as being in one of a countable number of states. Let (i, r) be a state of the system at time t, when the state of unit 1 is i and state of unit 2 is r at time t, Under some conditions, the opportunistic replacement policy that minimizes the expected total discounted cost or the average cost of maintenance is shown to be characterized by the control limits $i^{*}(r)$ (a function of r) and $r^{*}(i)$ (a function of i) : (a) in observed state (i, r), the optimal policy for unit 1 is to replace if $i{\ge}i^{*}(r)$ and no action otherwise; (b) in observed state (i, r), the optimal policy for unit 2 is to replace if $r{\ge}r^{*}(i)$ and no action otherwise. In addition, this paper also develops optimal policy in the finite time horizon case, where time horizon is fixed or a finite integer valued r.v. with known pmf.

• Journal of Convergence Society for SMB
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• v.6 no.4
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• pp.123-129
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• 2016

This study was conducted to understand influential factors in determining the advance directive attitudes of elderly patients. Structured survey questionnaires were distributed using a convenience sampling method to the residents of long-term-care facilities. As a result, the attitudes toward advance directives were accounted having 2.84 points, the functions of a family with 2.73 points, and the level of self-efficacy with 3.45 points. Participants who have higher family functions were found to have negative attitudes toward self-efficacy, as the relationship between two variables were in the negative correlation (r =-.324, p<.01). However, participants who have higher self-efficacy showed positive attitudes toward advanced directives as the two variables were in the positive correlation (r =.340, p<.01). This study will contribute to the settlement of the AD in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.452-456
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• 2004

Artemisia Herb is the dry aboveground part of Artemisia asiatica (Compositae). This is listed officially in the Korean Herbal Pharmacopoeia and used mainly in stopping all kinds of bleeding, regulating menses and curing menstrual disorders as well as in alleviating pain. Eupatilin and jaceosidin were isolated from Sazabalsuk and Sajuarisuk. and identified by means of spectral methods $(UV,\;^1H\;and\;^{13}C-NMR,\;MS) $ and quantitative analysis using HPLC. Regression equations for two flavonoid component standards obtained from Artemisia asiatica were $y=76069_x\;+\;107329\;(r=0.9999^{**})$ for eupatilin, $y=76651_x\;+\;77399\;(r=0.9996^{**})$ for jaceosidin. The eupatilin content of Sazabalsuk was 240mg, jaceosidin was 10mg in 100 g dry leaves. The Sajuarisuk were 330mg, 123mg in 100g dry leaves, respectively.

• Journal of Convergence for Information Technology
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• v.12 no.2
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• pp.107-115
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• 2022

The purpose of this study was to investigate the level of infection control knowledge and standard precaution practice and to identify effecting factors on standard precaution practice among nurses in small and midium-sized hospitals. A cross-sectional study was conducted with a sample of 258 nurses from 7 hospitals between July and August 2021. The mean score of infection control knowledge and standard precaution practice was 7.25 and 3.61, respectively. There were significant differences in standard precaution practice according to clinical experience (r=.123, p=.047) and position (F=5.356, p=.005). Infection control knowledge and standard precaution practice were closely correlated (r=.421, p<.001). Position (β=-.187, p=.025) and infection control knowledge (β=.408, p<.001) had an effect on standard precaution practice. It could be possible to enhance the standard precaution practice through convergence education program related to infection control among staff nurses.

• Journal of Korean Biological Nursing Science
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• v.19 no.3
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• pp.123-130
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• 2017

Purpose: This study aimed to identify factors influencing intra-operative core body temperature (CBT), and to develop a predictive model for intra-operative CBT in laparoscopic abdominal surgery. Methods: The prospective observational study involved 161 subjects, whose age, weight, and height were collected. The basal pre-operative CBT, pre-operative blood pressure, and heartbeat were measured. CBT was measured 1 hour and 2 hours after pneumoperitoneum. Results: Explanatory factors of intra-operative hypothermia (< $36^{\circ}C$) were weight (${\beta}=.361$, p< .001) and pre-operative CBT (${\beta}=.280$, p= .001) 1 hour after pneumoperitoneum (Adjusted $R^2=.198$, F= 7.56, p< .001). Weight was (${\beta}=.423$, p< .001) and pre-operative CBT was (${\beta}=.206$, p= .011) 2 hours after pneumoperitoneum (Adjusted $R^2=.177$, F= 5.93, p< .001). The researchers developed a predictive model for intra-operative CBT ($^{\circ}C$) by observing intra-operative CBT, body weight, and pre-operative CBT. The predictive model revealed that intra-operative CBT was positively correlated with body weight and pre-operative CBT. Conclusion: Influence of weight on intra-operative hypothermia increased over time from 1 hour to 2 hours after pneumoperitoneum, whereas influence of pre-operative CBT on intraoperative hypothermia decreased over time from 1 hour to 2 hours after pneumoperitoneum. The research recommends pre-warming for laparoscopic surgical patients to guard against intra-operative hypothermia.

• Korean Journal of Applied Biomechanics
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• v.25 no.1
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• pp.123-130
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• 2015

Purpose : The purpose of this study was to investigate the reliability of 3D-inertia measurement unit (IMU) based shoes in gait analysis. This was done with respect to the results of the optical motion capturing system and to collect reference gait data of healthy subjects with this device. Methods : The Smart Balance$^{(R)}$ system of 3D-IMU based shoes and Osprey$^{(R)}$ motion capturing cameras were used to collect motion data simultaneously. Forty four healthy subjects consisting of individuals in 20s (N=20), 40s (N=13), and 60s (N=11) participated in this study voluntarily. They performed natural walking on a treadmill for one minute at 4 different target speeds (3, 4, 5, 6 km/h), respectively. Results : Cadence (ICC=.998), step length (ICC=.970), stance phase (ICC=.845), and double-support phase (ICC=.684) from 3D-IMU based shoes were in agreement with results of optical motion system. Gait data of healthy subjects according to different treadmill speeds and ages were matched to previous literature showing increased cadence and reduced step length for elderly subjects. Conclusion : Conclusively, 3D-IMU based shoes in gait analysis were a satisfactory alternative option in measuring linear gait parameters.

• Transactions of Materials Processing
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• v.22 no.3
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• pp.123-132
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• 2013

Hot stamping, which is the hot pressing of special steel sheet using a cold die, can combine ease of shaping with high strength mechanical properties due to the hardening effect of rapid quenching. In this paper, a thermo-mechanical analysis of hot stamping using the finite element method in conjunction with phase transformations was performed in order to investigate the plastic deformation behavior, temperature history, and mechanical properties of the stamped car part. We also conducted a fully coupled thermo-mechanical analysis during the stamping and rapid quenching process to obtain the mechanical properties with the consideration of the effects of plastic deformation and phase transformation on the temperature histories at each point in the part. The finite element analysis could provide key information concerning the temperature histories and the sheet mechanical properties when the phase transformation is properly considered. Such an analysis can also be used to determine the effect of cyclic cooling on the tooling.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.1
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• pp.123-127
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• 2012

An experiment was carried out to boost the production of tasar crops through application of secondary nutrients. Different combinations of secondary nutrients were prepared and its effect was studied on the yield and quality of leaves of tasar food plant Terminalia tomentosa W & A with 2.4 m ${\times}$ 2.4 m spacing and cocoon characters of tasar silkworm Antheraea mylitta Drury reared on them. Among different combinations of secondary nutrients, foliar application of magnesium sulphate (2%, w/v) and basal application of 3 quintal/ha of calcium carbonate (secondary nutrient combination SM5) was found to be the best in crop improvement. It improves the quantity and quality of leaves as well as the commercial characters of cocoons. As a result, silk production improves. Under this combination, leaf yield increased by 26.55% in comparison to control. Average increase in moisture, total mineral, crude protein and total carbohydrate was 3.26%, 20.84%, 15.39% and 17.85% respectively as compared with control. Further, bio assay studies revealed that average larval weight, E.R.R., cocoon weight, shell weight and silk ratio percent increased by 11.25%, 25.71%, 20.05%, 35.14% and 12.17% respectively over control which indicates that secondary nutrient combination $SM_5$ has significant role in improving the production of tasar crops.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.3
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• pp.123-129
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• 2010

R&D innovation is based on the premises of gaining competitive advantage. Innovation is achieved not only through the development of technology for producing newer and better products, but also gaining and sharing information about consumer demands, changes in the market, and competitors actions. Investment in R&D can not adequately be fulfilled solely through market functions because of R&D activities imply high-risk, uncertainty, and because R&D has a public-good characteristic. Most past researches have concentrated on managerial methodologies through research of performance, thus the results are related to studies of innovation performance. This research looks into the effect given on R&D innovation by IT factors and provides a model, and further analysis on how IT factors are applied through this model. By developing a model through the process of re-structuring the model with variables based on the convergent and discriminant validity, and in turn confirming and concentrating on major IT factors through analysis, it will be possible to double the R&D Innovation Performance.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.1
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• pp.106-123
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• 2019

Demand for performance analysis is increasing for efficient use of limited budgets such as improving investment efficiency and strategic budget allocation in accordance with the continuous increase demand of R&D budget for developing advanced weapon systems in the future battlefields. In accordance with the Act on the Performance Evaluation and Performance Management of the National R&D Projects established in March 2006, the performance analysis has been conducted for the systematic management and utilization of the R&D project performance. It was recognized as a project to achieve self-defense through strengthening the weapons system development capability, however, efficiency evaluation of Defense R&D projects was not much emphasized. Research on the efficiency analysis of defense R&D projects has been conducted in recent years, but most studies focused on corporate efficiency and productivity of defense companies. In this study, we analyzed the three-stage performance of defence R&D projects based on the logical model using the data envelope analysis(DEA) model. We also analyzed performance analysis from various perspectives through R&D type, technology classification and performance model. This study is expected to help defense department improve defense R&D projects and make decision.