• Smart Structures and Systems
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• v.11 no.5
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• pp.533-553
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• 2013

In this paper, system identification of a cable-stayed bridge in Korea, the Hwamyung Bridge, is performed using vibration responses measured by a wireless sensor system. First, an acceleration based-wireless sensor system is employed for the structural health monitoring of the bridge, and wireless sensor nodes are deployed on a deck, a pylon and several selected cables. Second, modal parameters of the bridge are obtained both from measured vibration responses and finite element (FE) analysis. Frequency domain decomposition and stochastic subspace identification methods are used to obtain the modal parameters from the measured vibration responses. The FE model of the bridge is established using commercial FE software package. Third, structural properties of the bridge are updated using a modal sensitivity-based method. The updating work improves the accuracy of the FE model so that structural behaviors of the bridge can be represented better using the updated FE model. Finally, cable forces of the selected cables are also identified and compared with both design and lift-off test values.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.506-516
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• 2005

This paper deals with an investment scheduling problem of maximizing net present value of dividend with reinvestment allowed, where each investment has certain capital requirement and generates deterministic profit. Such deterministic profit is calculated at completion of each investment and then allocated into two parts, including dividend and reinvestment, at each predetermined reinvestment time point. The objective is to make optimal scheduling of investments over a fixed planning horizon which maximizes total sum of the net present values of dividends subject to investment precedence relations and capital limit but with reinvestment allowed. In the analysis, the scheduling problem is transformed to a kind of parallel machine scheduling problem and formulated as an integer programming which is proven to be NP-complete. Thereupon, a depth-first branch-and-bound algorithm is derived. To test the effectiveness and efficiency of the derived algorithm, computational experiments are performed with some numerical instances. The experimental results show that the algorithm solves the problem relatively faster than the commercial software package (CPLEX 8.1), and optimally solves the instances with up to 30 investments within a reasonable time limit.

• The Korean Journal of Health Service Management
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• v.9 no.2
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• pp.13-22
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• 2015

This study confirmed that the organizational health of nurses have an effect on customer orientation. This survey was conducted March 1 to 31, 2014 and a total of 210 questionnaires were used in the analysis. Descriptive statistics, t-test, ANOVA, factor analysis, and regression analysis were used to analyze the collected data in the SPSS software package. The findings are summarized as follows: First, the business environment and community-oriented organizations on health factors had an influence on customer orientation(p<.05, p<.001). Among the demographic factors, graduating from college as relevant to customer orientation. Seniority and rank in the lower tier showed that customer orientation is vulnerable. Second, when leadership was added to a conventional model, it had no significant effect on the dependent variables. The influence of community-oriented business environment factors on customer orientation was statistically significant(p<.01). In the result, we should apply proper organizational health factors to hospitals by investigating leadership, because there was difference in customer orientation according to type of leadership.

• Transactions of Materials Processing
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• v.17 no.4
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• pp.249-256
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• 2008

Combined phase transformation and heat transfer was considered on the simulation of hot press forming process, using material properties modeler, $JMatPro^{(R)}$ and a finite element package, $DEFORM^{TM}$-HT. In order to obtain high temperature mechanical properties and flow curves for different phases, a material properties modeler, $JMatPro^{(R)}$ was used, avoiding expensive and extensive high temperature materials tests. The results successfully show that the strength of hot press forming parts may exhibit different strength in the same parts, depending on the contact of blank with tooling. It was also shown effectively that the strength of the parts can be controlled by designing appropriate cooling paths and coolants. This was shown in terms of different heat convection coefficient in the calculation. Overall, current combination of software was shown to be an effective tool for the tool and process design of hot forming process, although the material modeler needs to be additionally verified by an appropriate set of high temperature materials test.

• The Journal of Korean Physical Therapy
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• v.23 no.2
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• pp.23-29
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• 2011

Purpose: The purpose of this study was to determine whether there is a relationship between strength balance and joint position sense related to the ankle joint in healthy women. Methods: Twenty-six healthy women were recruited. Isokinetic strength and joint position sense (JPS) were measured using a Biodex System 4 pro Dynamometer and a Biodex Advantage Software Package. Prior to measuring the JPS and isokinetic strength, the dominant foot was determined according to the Waterloo Footedness Questionnaire. After the JPS test, isokinetic strength was evaluated in velocity $60^{\circ}s$, including practice trial ($90^{\circ}s$). Using the measured isokinetic strength, a Strength Balance Index (SBI) was calculated. Results: Relative to the SBI, the degree of imbalance was varied; but there were imbalances. For each starting position, JPS error showed no significant differences (p>0.05). The relationship between SBI and JPS was found during the inversion to eversion process, eversion to inversion, and dorsi flexion to plantar flexion. Conclusion: There are moderate to mild relationships between JPS and SBI during ankle movement. It is suggested that to prevent ankle injuries, strength balance should be considered along with the other potential factors including anatomical alignment, proprioception, and soft tissues problems.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10b
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• pp.1129-1132
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• 2000

최근 인터넷 수요의 증가로 통신망에서 음성, 영상 및 데이터(data)를 복합적으로 지원할 수 있는 멀티서비스(multiservice)의 교환 기술이 필수적이다. 또한 망 사업자들이 여러 벤더(vendor)들로부터 최적의 장비를 선택하여 망을 구축할 수 있도록 통신 장비들의 상호 운용성을 지원하는 개방형 구조의 망 및 스위치 시스템(switch system)을 정의하는 작업이 필요하다. 페트리 넷(Petri Nets)은 시스템(system)을 분석하기 위한 도구로서, 시스템은 페트리 넷 이론에 의해 시스템의 수학적 표현인 페트리 넷으로 설계될 수 있다. CPN(Colored Petri Nets)은 페트리넷의 확장형으로서, 토근(token)에 칼라를 부여하여 다양한 특성을 지닌 시스템을 표현하기에 적합하다. Design/CPN은 CPN의 사용을 지원하는 소프트웨어 패키지(software package)이다. 본 논문에서는 개방형 멀티서비스 교환 시스템의 핵심으로 스위치와 제어기(Controller) 사이의 표준 프로토콜인 GSMP(General Switch Management Protocol) 프로토콜을 Design/CPN 으로 변환하고, 이로부터 시험열을 생성한다.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2751-2755
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• 2016

Background: Melanoma, the most life-threatening type of skin cancer, is a malignant tumor initiating in melanocytes that rapidly metastasizes and causes death. Materials and Methods: In this retrospective study, samples were selected from patients' information files in our Cancer Institute in Tehran with a designed checklist. A total of 322 files were found from 2003 until 2012. Then the raw data were transferred to Statistical Package for Social Sciences (SPSS) software version 16 and additional analysis was performed by Students t-test. The important variables were considered according to the available information from history of pathology including age, gender, occupation, stage and location of tumor. Results: Our data showed that incidence of melanoma has been different in the studied 10-year period according to age. Also, incidence of melanoma was higher in men than women. It was more common in lower limbs. More commonly housewives among women and farmers among men were affected by melanoma. Conclusions: Taken together the descriptive data clarified general aspects of this disease for further screening and interventions.

• Steel and Composite Structures
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• v.50 no.2
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• pp.159-181
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• 2024

In the present study, the effect of geometrical parameters of two different types of aluminum thin-walled structures on energy absorption under three-bending impact loading has been investigated experimentally and numerically. To evaluate the effect of parameters on the specific energy absorption (SEA), initial peak crushing force (IPCF), and the maximum crushing distance (δ), a design of experiment technique (DOE) with response surface method (RSM) was applied. Four different thin-walled structures have been tested under the low-velocity impact, and then they have simulated by ABAQUS software. An acceptable consistency between the numerical and experimental results was obtained. In this study, statistical analysis has been performed on various parameters of three different types of tubes. In the first and the second statistical analysis, the dimensional parameters of the cross-section, the number of holes, and the dimensional parameter of holes were considered as the design variables. The diameter reduction rate and the number of sections with different diameters are related to the third statistical analysis. All design points of the statistical method have been simulated by the finite element package, ABAQUS/Explicit. The final result shows that the height and thickness of tubes were more effective than other geometrical parameters, and despite the fact that the deformations of the cylindrical tubes were around forty percent greater than the rectangular tubes, the top desirability was relevant to the cylindrical tubes with reduced cross-sections.

• Imaging Science in Dentistry
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• v.50 no.2
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• pp.161-168
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• 2020

Purpose: The aim of this study was to evaluate the influence of voxel size and different post-processing algorithms on the analysis of dental materials using micro-computed tomography (micro-CT). Materials and Methods: Root-end cavities were prepared in extracted maxillary premolars, filled with mineral trioxide aggregate (MTA), Biodentine, and Intermediate Restorative Material (IRM), and scanned using micro-CT. The volume and porosity of materials were evaluated and compared using voxel sizes of 5, 10, and 20 ㎛, as well as different software tools(post-processing algorithms). The CTAn or MeVisLab/Materialise 3-matic software package was used to perform volume and morphological analyses, and the CTAn or MeVisLab/Amira software was used to evaluate porosity. Data were analyzed using 1-way ANOVA and the Tukey test(P<0.05). Results: Using MeVisLab/Materialise 3-matic, a consistent tendency was observed for volume to increase at larger voxel sizes. CTAn showed higher volumes for MTA and IRM at 20 ㎛. Using CTAn, porosity values decreased as voxel size increased, with statistically significant differences for all materials. MeVisLab/Amira showed a difference for MTA and IRM at 5 ㎛, and for Biodentine at 20 ㎛. Significant differences in volume and porosity were observed in all software packages for Biodentine across all voxel sizes. Conclusion: Some differences in volume and porosity were found according to voxel size, image-processing software, and the radiopacity of the material. Consistent protocols are needed for research evaluating dental materials.

• Journal of the Korean Home Economics Association
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• v.37 no.11
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• pp.139-156
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• 1999

Food choice is influenced by many factors including physical, social, psychological and food technological developments. This research is based on the survey on Puchon housewives dietary culture according to season and special occasions and the current consumption pattern of traditional fermented foods. The objective is to find out the current consumption and to use this data as the principal element needed to explore changes in consumption patterns and to uphold and develop the consumption of traditional fermented food. Questionnaires were collected 282 housewives in Puchon city. Data were analysed with SAS software package for t-test, F-test and Duncan’s multiple range test. Results of relationship between dietary culture of Puchon housewives and consumption patterns of traditional fermented food items; 1. If we look at seasonal foods, Puchon housewives responded that they normally prepare traditional foods for such special occasions as Chusok(89%), New Year(84%) and January full moon Day(77%). For family celebrations, they cook on their in-laws birthdays(91%), their husbands birthday(84%), childrens birthdays(73%) and their own birthday(32%). They also responded that they eat out on their own birthday(41%), on Christmas Day(19%), on childrens birthdays(17%) and on their husbands birthday(11%). 2. If we look at the age of housewives and their dietary culture, more young housewives tend to eat out on their own, their husbands and their childrens birthdays. As for their educational background, less educated housewives tend to prepare flood at home on New Years Day, while more educated housewives would eat out on their own birthdays. As for the type of family, mere housewives in nucleus families eat out on Christmas Days compared to those in extended families. Also, those in extended families tend to make food at home rather than eating out on their own birthdays. In case of the husbands birthday, there was some difference according to family income (p<0.03).