• Journal of Korea Water Resources Association
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• v.42 no.12
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• pp.1029-1038
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• 2009

Recently, it is expected that small hydropower (SHP) could potentially provide sufficient amounts of alternative energy in Korea where there is an abundance of potential sites and where social efforts are being made to reduce the emissions of green house gases. In the past, the resources survey for SHP development has been carried out using onsite surveys and paper maps, which incurred a great deal of time and cost. Furthermore, the tools for decision making such as determining development priorities or evaluating feasibility have been considered only economic aspect and focused on the performance characteristics of power generation. However, as the concept of sustainable development has been being advanced in recent years, especially focused on human-social, environmental and ecological in addition to economical sector; the consideration of these multiple criteria has become essential for sustainable SHP development. This study aims to propose the spatial multi-criteria decision making (MCDM) methodology for determining priorities among a number of locations on the planning stage of SHP development using AHP and GIS. The proposed methodology is applied for determining development priorities among the SHP locations in Cho River basin and this study presents the detailed spatial information data and the results of development priorities. As a fundamental work, this study will be beneficial to the future activation of SHP development and will help the decision making in evaluating the feasibility of SHP development.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.1
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• pp.45-51
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• 1995

The incidence of metastatic bony lesion has been increased recently, with the advanced therapeutic modalities of malignant tumors. The purpose of this study was to evaluate the effectiveness of surgical treatment in impending or established pathologic fractures due to metastasis in extremity. From 1981 to 1992, thirty two patients who had established or impending pathologic fractures in extremity had been treated surgically. The locations of metastasis, were lower extremity in 24 cases(femsral head and neck;5, intertrochanteric;7, subtrochanteric;8, femoral shaft;4) and upper extremity in 8 cases(proximal humerus;2, humoral shaft;6). The method of surgery was excision of tumor mass and rigid internal fixation to allow immediate mobilization, except 2 cases of amputation. The results were analysed by two criteria. The first was the grade of performance status that was made by modification of Functional Classification of New York Heart Association. The second was the degree of pain relief. The performance status was improved at least one grade in all patients and the mean improvement was 1.7 grades. The satisfactory pain relief was achieved in 81% of patients. Postoperatively, most of the patients had only slight to moderate limitation of physical activities and they became comfortable at rest and ordinary activities. The solitary metastatic lesions showed better pain relief(92%) than multiple metastasis(75%). The curative surgery was done in 3 cases, and they showed more than 24 months of disease-free survival.

• Journal of Yeungnam Medical Science
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• v.34 no.1
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• pp.62-68
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• 2017

Background: This study was conducted to examine the academic achievements of first year medical students in one medical school based on their characteristics and student selection factors of admission. Methods: The admission scores of student selection factors (Medical Education Eligibility Test [MEET], grade point average [GPA], English test score and interview) and demographic information were obtained from 61 students who had interviewed (multiple mini interview [MMI]) for admission (38 graduate medical school students in 2014, 23 medical college-transfer students in 2015). T-tests and ANOVA were used to examine the differences in academic achievement according to the student characteristics. Correlations between admission criteria scores and academic achievements were examined. Results: MEET score was higher among graduate medical students than medical college transfer students among student selection factors for admission. There were no significant differences in academic achievement of first grade medical school between age, gender, region of high school, years after graduation and school system. The lowest interview score group showed significantly lower achievement in problem-based learning (PBL) (p=0.034). Undergraduate GPA score was positively correlated with first grade total score (r=0.446, p=0.001) among admission scores of student selection factors. Conclusion: Students with higher GPA scores tend to do better academically in their first year of medical school. In case of interview, academic achievement did not lead to differences except for PBL.

• Journal of Information Technology Services
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• v.10 no.2
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• pp.177-188
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• 2011

This paper proposes a DEA model for the performance evaluation of each brand of coking coals in an integrated steel mill. The performance is defined as the efficiency which is the ratio of two linear combinations of the output factors to the input factors. There is only one input factor considered in the model : unit price of each brand based on CIF. Five output factors are chosen in consideration of their impact to the quality of cokes such as Ash, VM, LMF, TD, and Rm. Some of the output factors are treated as undesirable in DEA model because the quality criteria are given by the range. The CCR and BCC efficiencies are derived by the DEA model, and the scale efficiency is calculated, too. Each brand of coking coal is classified into four categories according to the CCR and BCC efficiencies, and the most inferior brands are identified as a result. The impact of the input and output factors to the efficiency is analyzed using a multiple regression, then the unit price is revealed as the most critical among them. Also, ANOVA results show that there exist efficiency differences among the coal types and the countries imported, respectively. Finally, the quantitative projection for the inefficient brands is performed if they are to be efficient. The result could be utilized in selecting the good or bad brands of coking coal based on the efficiency in an integrated steel mill. Also, this model will be used to assess the relative efficiency of a new brand of coking coal if it is a candidate to be imported.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.6B
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• pp.338-348
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• 2005

Currently, IEEE 802.11 Wireless LAN (WLAN) is rising as the most popular means for the broadband wireless access network. In this thesis, we propose a QoS(Quality of Service)-Oriented mechanism using handshaking method of scanning phase in IEEE 802.11 handoff. In conventional process for handoff, the major criterion to select the best AP(Access Point) among candidates is normally based on the RSS(Received Signal Strength), which does not always make the selected network guarantee the maximum achievable performance. Even though the link quality with a neighboring AP is excellent, the AP may not be a good candidate to handoff to simply because MAC(Medium Access Control) protocol of IEEE 802.11 standard is contention-based such as CSMA/CA. Therefore, if we apply network level information to AP selection criteria, we can achieve better handoff efficiency rather than before. The analysis and simulation results applied to our new mechanism show clearly better performance than AP selection based on traditional handoff method.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.13-22
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• 2007

This study was carried out to scrutinize possibility of manufacturing pitch pine (Pinus rigida) glued laminated timber in order to add values of pitch pine trees. Also, it was investigated to improve bending performance of pitch pine glulam. Pitch pine was imported as one of major plantation species in Korean peninsula. Machine stress rated grades of pitch pine lumber mostly ranged between E7 and E9. which grades were more or less inferior to producing high quality glulam. However, the adhesive properties between pitch pine and pitch pine, and between pitch pine and Japanese larch (Larix kaempferi Carr.), such as shear bond strength, wood failure rate and de-lamination rate of bonded layer submerged in cold and boiling water, were higher than Korean Standard criteria. These properties are essential for manufacturing glulam with single species or multiple species. The modulus of rupture (MOR) of pitch pine glulam exceeded the criterion of Korean Standard for glulam strength grade but modulus of elasticity (MOE) was lower than the criterion. On the other hand, the bending performances (MOR and MOE) were improved 20 percent by mixing with Japanese larch laminar. It is effective to arrange higher quality Japanese larch laminar at the outer layer of glulam for improving bending performances. In conclusion, it is possible to use low quality pitch pine as laminar of structural glulam for adding values of pitch pine.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.15-29
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• 2015

The purpose of this study is to identify the effect of job satisfaction on job performance and to examine the moderating effects of employment type of the employees in franchised Korean restaurants. The questionnaire was distributed to the employees in Korean restaurants having abroad branches of the 300 distributed questionnaire, and 271 copies were used in the analysis by exploring factor analysis, reliability analysis, correlation analysis, multiple regression and hierarchical moderated regression analysis through SPSS ver. 18.0. The results of the study were as followed; First, job satisfaction, the work and superior factor have positive influence on job performance, but wages and promotion factor have negative influence. Second, the employment type has the partially moderating effects between job satisfaction and job performance with interactive term(superior$^*$ employment type). On the basis of these results, it is suggested that the company has fair criteria for evaluating systems and reward program to the employees regardless of employment type. This study has the limitations of simple variable and employment type.

• KIPS Transactions on Software and Data Engineering
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• v.3 no.11
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• pp.471-478
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• 2014

Database replication is utilized to increase credibility, availability and prevent overload of distributed databases. Two models currently exist for replication - Master/Slave and Multi-Master. Since the Multi-Master model has problems of increasing complexity and costs to interface among multiple databases for updates and inserts, the Master/Slave model is more appropriate when frequent data inserts and updates are required. However, Master/Slave model also has a problem of not having exact criteria when systems choose to connect between Master and Slave for transactions. Therefore, this research suggests a routing algorithm based on AOP (Aspect Oriented Programming) in the Master/Slave database model. The algorithm classifies applications as cross-cutting concerns based on AOP, modularizes each concern, and routes transactions among Master and Slave databases. This paper evaluates stability and performance of the suggested algorithm through integration tests based on scenarios.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1389-1400
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• 2013

This study developed an operating rule curve (ORC) for multipurpose water supply (irrigation and environmental water) in heightened agricultural reservoir. Among the 20 reservoirs in improvement project of agricultural reservoir dam heightening, the 4 representative reservoirs (Ungyang, Gungchon, Yongam and Unam) were selected for the study according to the analysis of statistical characteristics. Available environmental water supply amounts during irrigation and non-irrigation periods, which is the range from release restricted water level to high water level were estimated by water balance analysis using reservoir operation model. Reliability, resiliency and vulnerability criteria for water system performance were used to assess the multiple water supply capacity. The ORC was presented as the percentile rank for the daily reservoir water level from the results of reservoir operation using the past couple of decades weather data. The water levels for each percentile were divided into 3 buffer sections representing drought (5~25%), normal (25~75%), and flood (75~95%) year to operate the heightened agricultural reservoir with ORC.

• Journal of Korean Physical Therapy Science
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• v.10 no.1
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• pp.109-121
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• 2003

The purpose of this study was to test the difference of sitting balance control between a normal group and a group of patients with low back pain when their eyes were opened or closed. The 30 subjects of the control group had been chosen from healthy individuals who fit into the pre-designed criteria, and the 30 subjects of the experimental group were composed of the patients with LBP who had their treatment from S hospital from september 1, 2002, to October 30, 2002, and the subjects were measured by static balance test by using a balance performance monitor(BPM). Static balance test was done twice for each subject with his or her eyes opened and closed. Collected data were statistically analyzed by SPSS/PC using unpaired T-Test, Pained T-Test and multiple regression. The results were as follows: 1. In static balance test, normal group did not show statistical significance in sway angle(Anterior, Posterior, left and Right), sway path, sway area and maximal sway velocity, but showed statistical significance in mean balance with eyes opened and eyes dosed(P<.05) 2. In static balance test, LBP group did not show statistical significance in sway angle(Anterior, Posterior, left and Right), mean balance, sway path, sway area and maximal sway velocity with eyes opened and eyes dosed 3. With eyes opened, the comparison between the normal group and the LBP group showed statistical significance in sway angle(Anterior, Posterior, left and Right), mean valance, sway path, sway area and maximal sway velocity(p<.05). With eyes closed, normal group and LBP group did not show statistical significance in sway angle(Anterior and Right), sway area, but showed statistical significance in sway angle(Posterior and Left), mean balance, sway path, sway area and maximal sway velocity(p<.05) In conclusion, there was a significant difference in static sitting balance between normal group and LBP patients group. For future studies, I strongly suggest that researches be done on the treatment with LBP by predicting changes of postures and manipulating them.