• The Journal of the Korea Contents Association
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• v.15 no.8
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• pp.293-303
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• 2015

This study examined the relationships among work-family role conflicts(WFC, FWC), work distress(WDIS), and life satisfaction(LS) for female workers using child daycare center in workplace. From the data of 137 female workers, it showed statistically significant results that FWC on WDIS and WDIS on WFC were positive. It also demonstrated the degree of WFC was higher, the LS level was lower. The results revealed not only WDIS fully mediated between FWC and LS, but also WFC partially mediated the relationship between WIDS and LS. Comparing to the previous studies that failed to tell the directions of work-family role conflicts on LS, this study distinguished the bi-directional work-family role conflicts in searching for causal relationships among WFC, FWC, WDIS, and LS. This study recommended further studies for comparing female workers using child daycare center in workplace or not.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.531-541
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• 2020

In this study, a computed tide of a real tide was introduced to improve the numerical solutions for tides and tidal flow simulations. The real tide was defined considering the nodal modulation amplitude, phase correction factor, astronomical argument, and tidal harmonic constants of all the constituents. The numerical simulation was performed using the real tide parameters for the west-south coastal waters of Korea, where the observation data for tides, tidal currents, waves, and winds over two seasons exist. The tidal flow simulation of the real tide was simulated successfully. The correlation coefficient between the observed and calculated values was 1.0, which indicated both accurate amplitude and phase. The U- and V-components of the tidal current obtained for the real tide had average valid correlations of 0.83 and 0.936, respectively. The speed error for the residual current was 0.006 m/s on the average, which indicated an insignificant difference, and the directional behavior of the residual current was very similar. In addition, the velocity error was attributed to various weather effects, such as high waves and wind storms. Therefore, this model is expected to improve current solutions provided that weathering forces, such as waves and winds, are considered.

• Journal of Nutrition and Health
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• v.38 no.9
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• pp.765-776
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• 2005

The purposes of this study were to a) examine IC (intellectual capital) circumstance of CFMC (contract foodservice management company), b) identify the correlation between IC of CFMC, c) analyze the cause and effect of IC in the viewpoint of contractor, client, and customer. The questionnaires of IC measurement were handed out to 108 CfHCs, there composing of main office employees, foodservice managers, customers, and clients of 207 school, 38 hospital, and 86 business/industry foodservices. The statistical data analysis was completed using SPSS Win (ver 12.0) for descriptive analysis, correlation analysis, simple linear regression analysis. First, CFMCs had operational experience for an average of 8 years and 8 months, and served an average of 38,540 meals a day. Most of the respondent companies operated 'food supply/distribution($50\%$)', 'catering ($46.7\%$)', and restaurant business ($43.3\%$)' except for institutional foodservice and managed an average of 66 clients for the contract period of 2 years and 3 months. Second, there was positive correlation between $\ulcorner$sales of foodservice$\lrcorner$ and 'market ability', $\ulcorner$client satisfaction$\lrcorner$ and necessary intellectual capital for managing branch/chain foodservice office, and $\ulcorner$customer satisfaction$\lrcorner$ and $\ulcorner$renewal and development$\lrcorner$, 'market ability', 'infrastructure support for foodservice operation', 'employee satisfaction', respectively. Finally, the result of the cause and effect analysis on CFMCs, clients, and customers was positively influenced by 'client satisfaction' with 'customer satisfaction', 'infrastructure support for foodservice operation' and 'customer satisfaction' with 'employee satisfaction', and 'infrastructure support for foodservice operation'. In conclusion, if CFMCs were to perform a routine checkups by utilizing CFMC's IC measuring tool, improvements in CFMC operational capacities as well as foodservice quality can be noted. Additionally, CFMCS can satisfy their client-customer relationship by employing internal marketing thechniques for employee, a more efficient infrastructure support system, and construc tive infrastructure utilization. Therefore, CFMCs can show significant improvement in their sales and foodservice quali-ty though continuous maintenance of the client and customer satisfaction.

• Journal of Satellite, Information and Communications
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• v.2 no.2
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• pp.69-74
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• 2007

Recently, the demands for the satellite broadband mobile communication services are increased. To provide these services, mobile satellite communication systems for the passengers or crews on the high-speed moving vehicles, are being developed for the last several years especially in the Europe and North America. However, most of these systems can provide only several hundred kbps of transmission rate and this is not enough performance to provide satellite internet service for the group users such as passengers on the high-speed train. Moreover, service availability with these systems is limited to be rather low because they don't have any countermeasure scheme for the N-LOS environment which happens often along the railway. This paper describes mobile broadband satellite communication system, which is on the development, to provide high data-rate internet services to the high-speed trains. This system is applied with the inter-networking scenarios of both satellite/terrestrial network and satellite/gap-filler network so that it can provide seamless service even in the train operating environment, and these inter-networking schemes result in high service availability. And this system also has the countermeasure schemes, such as upper layer FEC and antenna diversity, for the short fading which is occurred periodically on the railway due to the power supplying structures so that it can provide high speed internet services. Mobile DVB-S2 technology which is now being standardized in the DVB is used for the forward-link transmission and DVB-RCS for the return-link.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.3
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• pp.19-28
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• 2013

This study evaluated the quantitative effects of the deployment of semi-actuated signal systems using field data. For this, a semi-actuted signal system was deployed in the regional roadway network extensively. This paper investigated an operating strategy of semi-actuated signal systems for field application, and implemented the functional strategy into the standard signal controller. The performance was evaluated using three measures of effectiveness such as traffic volume, travel time, and the number of delayed vehicle. From the analysis results, traffic volume increased about 9.4% and 11.3% for morning and evening peak periods, respectively. The average travel time was reduced about 6.3% and 7.8% during morning and evening peak periods, respectively because of the expansion of bandwidths for major streets. In addition, the number of delayed vehicles was reduced about 36.4% and 23.9% for morning and evening peak periods, respectively. It is expected that the effectiveness of signal control system can be improved by incorporating a properly designed semi-actuated signal system in regional roadways with directional demand variation.

• International Journal of Highway Engineering
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• v.7 no.4 s.26
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• pp.21-30
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• 2005

Traffic volume data have been used for the plan, the design, and the operation of highway. Since 1955, traffic survey has been nation- widely carried out at national highway and the regular survey in national highway has been conducted at the intersections of highways. However, it is critical issue to select the priority of the regular survey because it is almost impossible to conduct regular survey at all intersections of national highways. In this study, MCDM(Multiple Criteria Decision Making) using AHP(Analytic Hierarchy Process) was applied to decide the priority of the regular survey. The following standard variables for determining the priority was selected the highway plan variables[AADT, VKT, Peak Hourly Volume, Location of highway from Urban], the highway design variables[Volume(pcu), Directional Traffic Volume, Heavy Vehicle Rate], and the highway operation variables[Speed, Density, V/C]. The standard variables were quantified and normalized. Using the Eigen vector method, the weighted values of each hierarchy based on the pair-wise comparison values from the questionnaire survey were calculated. The selection of the priority of regular survey was dependent on the size of the product of the weighted values for each hierarchy and the normalized values for the standard variables. Finally, the priority of regular survey of the intersections of national highways was determined according to the order in the size of the product of two values.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.4
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• pp.679-700
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• 1996

Inferior alveolar nerve dysfunction may be the result of trauma, disease, or iatrogenic injury. Inferior alveolar nerve injury is inherent risk in endodontic therapy, orthognathic surgery of the mandible, and extraction of mandibular teeth, particularly the third molars. The sensory disturbances of inferior alveolar nerve associated with such injury have been well documented clinical problem that is commonly evaluated by several clinical sensory test including Tinels sign, Von Frey test(static light touch detection), directional discrimination, two-point discrimination, pin pressure nociceptive discrimination, and thermal test. These methods used to detect and assess inferior alveolar nerve injury have been subjective in nature, relying on the cooperation of the patients. In addition, many of these techniques are sensitive to differences in the examiners experience and skill with the particular technique. Data obtained at different times or by different examiners are therefore difficult to compare. Prior experimental studies have used electro diagnostic methods(sensory evoked potential) to objectively evaluate inferior alveolar nerve after nerve injury. This study was designed with inferior alveolar nerve of rabbit. Several types of injury including mind, moderate, severe compression and perforation with 19 gauze, 21 gauze needle and 6mm, 10mm traction were applied for taking the sesory evoked ppterntial. Latency and amplitude of injury rabbit inferior alveolar nerve were investigated with sensory evoked potential using unpaired t-test. The results were as follows : 1. Intensity of threshold (T1) was $128{\pm}16{\mu}A$ : latency, $0.87{\pm}0.07$ microsecond : amplitude, $0.4{\pm}0.1{\mu}V$ : conduction velocity, 23.3 m/s in sensory evoked potential of uninjured rabbit inferior alveolar nerve. 2. Rabbit inferior alveolar nerve consists of type II and III sensory nerve fiber. 3. Latency was increased and amplitude was decreased in compression injury. The more injured, the more changed in latency and amplitude. 4. Findings in perforation injury was similar to compression injury. Waveform for sensory evoked potential improved by increasing postinjured time. 5. Increasing latency was prominent in traction injury rabbit inferior alveolar nerve. 6. In microscopic histopathological findings, significant degeneration and disorganization of the internal architecture were seen in nerve facicle of severe compression and 10mm traction group. From the above findings, electrophysiological assessment(sensory evoked potential) of rabbit injured inferior alveolar nerve is reliable technique in diagnosis and prognosis of nerve injury.

• The KIPS Transactions:PartC
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• v.11C no.6 s.95
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• pp.799-806
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• 2004

A growing diversity of pervasive devices is gaming access to the Internet and other information. However, much of the rich multimedia contents cannot be easily handled by the client devices because of the limited communication, processing, storage and display capabilities. The in-tegration of voice, data and video service modified the target of networking technologies. Networks must have some the capabilities for in-tegration of various services and also for QoS support as required by each of those service. Because of these reasons, we developed EAGIS(Efficient ATM Gateway for real time Internet Service) to provide seamless multimedia service between the ATM network and the Internet. EAGIS consists of the interworking unit, content server, transcoding server, and the serveice broker to provide seamless multimedia service be-tween the ATM network and the Internet. In this paper, we design the architecture and transcoding service scenario of the EAGIS. When the RTP is used for the bi-directional communication, transcoding time is configured by the time-stamp of RTCP. When HTTP is used for unidirec-tional communication, self-timer is used. By using these reference time, standard transcoding method is applicable according to the frame trans-mission rate and network traffic load. And we can also assure the QoS of the multiple users` effective bandwidth by our algorithm.

• Composites Research
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• v.32 no.6
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• pp.327-334
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• 2019

The delamination is a special mode of failure occurring in composite laminates. Several numerical studies with finite element analysis have been carried out on the delamination behavior of unidirectional composite laminates. On the other hand, the fracture for the multi-directional composite laminates may occur not only along the resin-fiber interface between plies known as interply or interlaminar fracture but also within a ply known as interyarn or intralaminar fracture accompanied by matrix cracking and fiber bridging. In addition, interlaminar and intralaminar cracks appear at irregular proportions and intralaminar cracks proceeded at arbitrary angle. The probabilistic analysis method for the prediction of crack growth behavior within a layer is more advantageous than the deterministic analysis method. In this paper, we analyze the crack path when the mode I load is applied to the cross-ply carbon/epoxy composite laminates and collect and analyze the probability data to be used as the basis of the probabilistic analysis in the future. Two criteria for the theoretical analysis of the crack growth direction were proposed by analyzing the stress field at the crack tip of orthotropic materials. Using the proposed method, the crack growth directions of the cross-ply carbon/epoxy laminates were analyzed qualitatively and quantitatively and compared with experimental results.

• Journal of Korea Port Economic Association
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• v.23 no.1
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• pp.1-18
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• 2007

The purpose of this study is to examine the effect of exchange rate volatility on Trading Volume of Container of Korea, and to induce policy implication in the contex of GARCH and regression model. In order to test whether time series data is stationary and the model is fitness or not, we put in operation unit root test, cointegration test. And we apply impulse response functions and variance decomposition to the structural model to estimate dynamic short run behavior of variables. The major empirical results of the study show that the increase in exchange rate volatility exerts a significant negative effect on Trading Volume of Container in long run. The results Granger causality based on an error correction model indicate that uni-directional causality between trading volume of container and exchange rate volatility is detected. This study applies impulse response function and variance decompositions to get additional information regarding the Trading Volume of Container to shocks in exchange rate volatility. The results indicate that the impact of exchange rate volatility on Trading Volume of Container is negative and converges on a stable negative equilibrium in short-run. Th exchange rate volatility have a large impact on variance of Trading Volume of Container, the effect of exchange rate volatility is small in very short run but become larger with time. We can infer policy suggestion as follows; we must make a stable policy of exchange rate to get more Trading Volume of Container