• Journal of Biomedical Engineering Research
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• v.31 no.3
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• pp.199-209
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• 2010

The locking compression plates-distal femur(LCP-DF) are being widely used for surgical management of the extra-articular complex fractures of the distal femur. They feature locking mechanism between the screws and the screw holes of the plate to provide stronger fixation force with less number of screws than conventional compression bone plate. However, their biomechanical efficacies are not fully understood, especially regarding the number of the screws inserted and their optimal configurations. In this study, we investigated effects of various screw configurations in the shaft and the condylar regions of the femur in relation to structural stability of LCP-DF system. For this purpose, a baseline 3-D finite element (FE) model of the femur was constructed from CT-scan images of a normal healthy male and was validated. The extra-articular complex fracture of the distal femur was made with a 4-cm defect. Surgical reduction with LCP-DF and bone screws were added laterally. To simulate various cases of post-op screw configurations, screws were inserted in the shaft (3~5 screws) and the condylar (4~6 screws) regions. Particular attention was paid at the shaft region where screws were inserted either in clustered or evenly-spaced fashion. Tied-contact conditions were assigned at the bone screws-plate whereas general contact condition was assumed at the interfaces between LCP-DF and bone screws. Axial compressive load of 1,610N(2.3 BW) was applied on the femoral head to reflect joint reaction force. An average of 5% increase in stiffness was found with increase in screw numbers (from 4 to 6) in the condylar region, as compared to negligible increase (less than 1%) at the shaft regardless of the number of screws inserted or its distribution, whether clustered or evenly-spaced. At the condylar region, screw insertion at the holes near the fracture interface and posterior locations contributed greater increase in stiffness (9~13%) than any other locations. Our results suggested that the screw insertion at the condylar region can be more effective than at the shaft during surgical treatment of fracture of the distal femur with LCP-DF. In addition, screw insertion at the holes close to the fracture interface should be accompanied to ensure better fracture healing.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.537-545
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• 2005

Traditionally Jeju island has a mild oceanic climate throughout the year and famous as worldwide resort area bemuse of its pure natural environment and dramatic coastal scenery. But unpredicted coastal erosion problem, mused by variation of environmental conditions from construction of coastal structure and renovation of the existing ports, has raised its head above the water, and is becoming serious these days just like other coastal area in Korea. The phenomena happen here along the seaside of southern part of the island show that severe changes in coastal line from erosion and even witnessed the coastal cliff failure. In advanced countries, coastal engineers and researchers have studied deeply about this kind of problem for a long time. However, as it is not sot active in Korea and lack of research data, there exists difficulties on building protection methods and thoughtless constructions might make it more complicated and fatal to the coastal environment. In this study, we investigated some case studies of other countries and intended to induce and propose some integral protection methods for coastline erosion, considering environmentally sound and water friendly way of development such as artificial reef, floating breakwater, and double cellblock breakwater. Finally, we made analysis on the proposed methods with numerical model test and evaluation on the feasibility of each method.

• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.577-582
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• 2008

In order to ascertain the effect of ship's speeds, in maneuver under the condition of strong cross current in the breakwater channel of Busan port, this paper is to deal with the analyses of vessel proximity measures, vessel controllability measures, and ship handlers' subjective evaluation measures of simulated maneuvers, which were carried out by 76 ship handlers who conned Panamax bulk carrier of 60,000 DWT, The set and drift of current are southwesterly and 2 knots. The speeds of the model ship are 5 knots & 10 knots respectively. The followings are concluded. ${(1)}$ In the approaches of the breakwater of Busan port, ship handlers psychologically tend not to give the drift angle of more than $10^{\circ}$ bemuse ship's head points out of the entrance. ${(2)}$ Ship handlers' subjective evaluation, vessel proximity and controllability measures are relatively larger under the speed of 5 knots than under that of 10 knots. due to direct pressure of strong current. ${(3)}$ A single index of controllability measures was suggested, by removing their units.

• Journal of Ginseng Research
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• v.44 no.6
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• pp.833-842
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• 2020

Background: Ulcerative colitis (UC) is a commonly encountered large intestine disease in the contemporary world that terminates into colorectal cancer; therefore, the timely treatment of UC is of major concern. Panax ginseng Meyer is an extensively consumed herbal commodity in South East Asian countries, especially Korea. It exhibits a wide range of biologically beneficial qualities for almost head-to-toe ailments in the body. Epimedium koreanum Nakai (EKN) is also a widely used traditional Korean herbal medicine used for treating infertility, rheumatism, and cardiovascular diseases. Materials and methods: Separately the anti-inflammatory activities of both red ginseng extracts (RGEs) and EKNs had been demonstrated in the past in various inflammatory models; however, we sought to unravel the anti-inflammatory activities of the combination of these two extracts in dextran sulfate sodium (DSS)-induced ulcerative colitis in mice model because the allopathic remedies for UC involve more side effects than benefits. Results: Our results have shown that the combination of RGE + EKN synergistically alleviated the macroscopic lesions in DSS-induced colitic mice such as colon shortening, hematochezia, and weight loss. Moreover, it restored the histopathological lesions in mice and decreased the levels of proinflammatory mediators and cytokines through the repression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP-3) expression. In vitro, this combination also reduced the magnitude of nitric acid (NO), proinflammatory mediators and cytokine through NF-κB and mitogen-activated protein kinase (MAPK) pathways in RAW 264.7 mouse macrophage cells. Conclusion: In the light of these findings, we can endorse this combination extract as a functional food for the prophylactic as well as therapeutic treatment of UC in humans together with allopathic remedies.

• Journal of Korea Water Resources Association
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• v.42 no.1
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• pp.21-31
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• 2009

The characteristics, intensity and direction of groundwater.surface water interactions are controlled by groundwater head gradients, hydraulic conductivity and by the riverbed geometry. As a result of the spatial heterogeneity of these factors and the subsequent variability of the impact of these interaction processes, the water balance is also characterized by highly variable spatial patterns and temporal dynamics. However, spatially detailed studies concerning the spatio-temporal variability of the extent and intensity of surface-groundwater interactions have been limited to the investigation of cross-sections or small stream reaches. Thus, the extensive study on the watershed based interaction between surface water and groundwater is to be analyzed. In this study, the intensity and the spatial extent of interactions along the stream were found by using integrated SWAT-MODFLOW model. This integrated modeling approach was applied to Anyangcheon watershed in Korea. The effluent stream characteristics were found in the watershed, namely, baseflow was annually discharged except heavy rainy periods. The intensity and the spatial extent of surface-groundwater interactions in different sub-watersheds were found on a daily basis. The influential extent of surface-groundwater interaction become larger as the watershed elevations are lower.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.4
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• pp.1307-1315
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• 2014

This study aims to analysis of determinants of the residents satisfaction of purchased rental housing and currently being implemented policy of supporting low-income families are empirically evaluated through the residential evaluation of purchased rental housing residents. Purchased rental housing users are possible to live in currently residing community consistently, have advantages for fewer problems of the phenomenon of social isolation, exclusion and preventing slumism of low-income families, are expected to increase in the future. First of all, the characteristics of residential environment, housing expenses and a head of household were examined for the residential environment evaluation of the residents of purchased rental housing, on the basis of this, the characteristics of internal and external house and residential location are examined each for the determinants of the residential environment satisfaction of purchased rental housing. The variables that affect residential satisfaction according to residential location are public facilities, educational facilities and welfare facilities respectively. In particular, the higher the satisfaction of access to welfare facilities, the higher the satisfaction of residential location of purchased rental housing was analyzed. The variables affecting the residential satisfaction according to the internal and external characteristics of house are significant in window status, cracking, heating facilities, housing scale and management.

• The korean journal of orthodontics
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• v.41 no.1
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• pp.6-15
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• 2011

Objective: The aim of this study was to evaluate the biomechanical aspects of peri-implant bone upon root contact of orthodontic microimplant. Methods: Axisymmetric finite element modeling scheme was used to analyze the compressive strength of the orthodontic microimplant (Absoanchor SH1312-7, Dentos Inc., Daegu, Korea) placed into inter-radicular bone covered by 1 mm thick cortical bone, with its apical tip contacting adjacent root surface. A stepwise analysis technique was adopted to simulate the response of peri-implant bone. Areas of the bone that were subject to higher stresses than the maximum compressive strength (in case of cancellous bone) or threshold stress of 54.8MPa, which was assumed to impair the physiological remodeling of cortical bone, were removed from the FE mesh in a stepwise manner. For comparison, a control model was analyzed which simulated normal orthodontic force of 5 N at the head of the microimplant. Results: Stresses in cancellous bone were high enough to cause mechanical failure across its entire thickness. Stresses in cortical bone were more likely to cause resorptive bone remodeling than mechanical failure. The overloaded zone, initially located at the lower part of cortical plate, proliferated upward in a positive feedback mode, unaffected by stress redistribution, until the whole thickness was engaged. Conclusions: Stresses induced around a microimplant by root contact may lead to a irreversible loss of microimplant stability.

• Journal of the Korean Geotechnical Society
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• v.28 no.5
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• pp.27-39
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• 2012

In this paper, a series of centrifuge tests were performed to evaluate the seepage characteristic of reinforced embankment. The centrifuge models simulated an actual embankment reinforced by enlargement of levee cross-section. The centrifuge models have the same conditions except the locations of enlargement with low permeable material : water-side and land-side. In addition, the prototype embankment is constructed on low permeable clay layer. In the case of water-side reinforcement, the reinforced zone makes water head down and the saturated zone of embankment propagates slowly. In the case of land-side reinforcement embankment, the saturated zone enlarged relatively faster but the amount of exit water at land-side toe was very small because of the land-side reinforcement zone. The low permeable clay foundation layer was being continuously saturated by the inflow from the embankment as well as the uplift flow from the permeable layer induced by the excess pore water pressure.

• Culinary science and hospitality research
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• v.16 no.5
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• pp.149-163
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• 2010

This study planned study model through documentary research and drew hypothesis to analyze how teamwork of servant leadership has an influence on job satisfaction aiming at full time employee under department head and contract worker of five star hotel in Busan. As a survey term, from April 5th, 2010 to April 23th, 2010, it distributed total 300 questionnaires, 60 questionnaires for each hotel, and then 242 questionnaires were used for empirical analysis. It analyzed data using SPSS WIN Version 12.0 statistics package program, and verified through frequency analysis, reliability analysis, factor analysis, regression analysis. As a result of verification for influence of servant leadership on interchange which is one of teamwork, it showed that community formation factor has a positive influence on interchange, and as a result of verification for influence on communication which is one of teamwork, I could find out that higher the level of bond of sympathy formation and community formation factor are, higher the communication becomes. As a result of verification for influence on interdependence which is one of teamwork, it showed that community formation, stewardship, vision, commitment to growth factor have a positive influence on interdependence. As a result of verification for influence of teamwork factor on job satisfaction, it showed that all factors have a positive influence. As a result of this study. I could find out that member' positive perception on leader in hotel organization can be a basis deriving job satisfaction though teamwork.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.1
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• pp.63-76
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• 1999

The main objective of this study was to develop a concept of service marketing promotion in nursing that is derived from the concepts of service marketing theory. This research was a descriptive study, at the factor isolation level. The principle of concept derivation suggested by Walker and Avant (1988) and the Hybrid model suggested by Schwarz-Barcott and Kim (1993) were employed as the research method. The data were collected from December, 1997 to April. 1998 at a large general hospital located in Seoul. The procedures of this study were as follows: First. at the theoretical phase: the meaning, attributes, and definition of service marketing promotion were identified through an extensive review of the literature. Second, at the empirical phase: fieldwork was done to identify the promotional activities and events in nursing. Top nurse managers from 4 units (Director of Nursing, Head nurses of inpatient nursing unit, outpatient nursing unit. and home care nursing unit) were interviewed and the content of the interview was analyzed to identify the meaning and attributes of promotion in nursing. Other methods such as brochures and other audio-visual materials which were relevant to nursing promotion were used to supplement the interviews. Finally, the results of the theoretical and empirical analyses were intergrated to develop a concept of service marketing in nursing practice. A final definition of service marketing promotion in nursing was identified as follows. 1. Promotion as a marketing function in nursing service is concerned with communication to target markets on all information related to nursing service in order to satisfy the objectives of both a nursing service organization and the target markets. 2. The goals of nursing service promotion include: 1) increasing visibility of nursing services and delivering the information on nursing services, 2) affirming the value of nursing services, so it can contribute to formulation of reimbursement policy for nursing services. 3) advancing the general image of the nursing profession and nursing services. 4) achieving and attaining a desirable positioning for nurses among health care professionals. and 5) creating and stimulating the demand for nursing services. 3. In order to obtain these goals it is necessary to provide information on nursing services, to persuade target markets. to remind them about nursing services. and to establish a collaborative relationship with related departments. 4. The tools used to carry out the above functions of promotion in nursing are the providing nursing services, public relations and publicity. QA of nursing, advertising, and sales promotion. 5. The target markets of nursing service include the nursing customer markets. the internal markets, the influence markets. the recruitment markets. the supplier markets. and the nursing referral markets. In conclusion, the concept of promotion in other service marketing areas can be applied to the promotion of nursing service marketing. The promotion of nursing service is more than just effective communication in nursing service. it is the effective use of the concepts of service marketing promotion. Promotion of nursing service will contribute to create and expand nursing services.