• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.197-208
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• 2017

The purpose of this study was to construct and test a structural equation model for college student's gambling behavior. A structured questionnaire was completed by 246 college students to analyze the relationships between perspective factors(irrational gambling belief), psychological factors(depression, anxiety), social factors(parental monitoring, parental support, friend support), self-control and gambling behavior. The moderating effects of gender, friends and family's gambling behaviors were examined. The data were analyzed using SPSS 21,0 and AMOS 20.0 programs. Self-control and psychological factors directly affected the college student's gambling behavior, while perspective factors and social factors affected it indirectly. The model fit indices of the modified model were suitable for the recommended levels. The overall study findings suggest the need to develop a gambling prevention program for college students that reinforces self-control, parental monitoring and support, and friend support while reducing irrational gambling belief, depression, and anxiety. An approach that considers gender and a development of a group counseling program for family or friends are also required.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.12
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• pp.1371-1380
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• 2007

Study on the instability of waste plastic's thermal pyrolysis oil was carried out for the purpose of improving its quality. The reaction of pyrolysis oil with ozone changed double bonds into aldehydes and ketone, estimated that HDPE pyrolysis oil contained $\sim45$ wt% 1-alkene type olefins, and PP pyrolysis oil did $\sim73$ wt% olefins, which consisted of $\sim47$ wt% secondary and $\sim20$ wt% primary alkenes. The dark brown color and odor of pyrolysis oil were improved by eliminating double bonds, indicated that they were directly related to unsaturated hydrocarbons. Container test showed that metal can affected oil quality worse than the brown glass bottle. Antioxidant added into pyrolysis oil was consumed up to 90% within $2\sim3$ days and the wt. composition of unsaturated hydrocarbons in pyrolysis oil was not changed within 50 days, inferring that instability of pyrolysis oil due to unsaturated bonds can be stabilized by antioxidants. Adsorption test on silica gel, activated carbon and alumina to remove precipitates in oil produced a good result, but not enough to remove moisture. However, cheap anhydrous sodium carbonate showed the best removal efficiency of moisture as well as precipitates in oil. Therefore the pyrolysis oil quality improvement was accomplished by applying anhydrous $Na_2CO_3$ into the production plant.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.1
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• pp.43-55
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• 2018

The biggest change in the field of coastal ship safety control since the accident of passenger ship Sewol has been the introduction of the maritime safety supervisor system. With its introduction, the safety control system in coastal passenger ships was changed from consisting of operation managers and marine police to operation managers and a newly-introduced maritime safety supervisor. The safety control system for coastal cargo ships was also converted from relying on ship inspection officers to having a maritime safety supervisor and ship inspection officers. However some negative elements have surfaced due to confusion related to the scope of work in the coastal cargo shipping field. These have been caused by dividing the supervisory agency, a lack of work continuity given non-permanent public official status, low supervisor qualifications overlooking reality, and limitations of the order for improvement to secure seaworthiness. It is essential that the maritime safety supervisor system be solidified to reinforce coastal ship safety control. Therefore, systematic safety control in the coastal cargo shipping industry should be conducted by a single, integrated government agency, and the area covered by the order for improvement to secure seaworthiness should be extended. Also limitations of the supervisor recruitment system due to non-permanent public official status should be simultaneously improved. In addition, it is necessary to upgrade supervisor qualifications to require experience with surveyors of international class, ship captains, and chief engineers.

• Journal of Yeungnam Medical Science
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• v.20 no.2
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• pp.160-168
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• 2003

Background: Confirm the stability of intervertebral disc sustaining each fused lumbar spine cases, comparing vertical compression, A-P shear force and rotational moment on intervertebral disc of instrumented lumbar spine with simple vertical compression load and follower load using finite element analysis. Materials and Methods: We analyze the stability of intervertebral disc L4-5 supporting fused lumbar spine segments. After performing finite element modelling about L1-L5 lumbar vertebral column and L1-L4 each fusion level pedicle screw system for fused lumbar spine fine element model. Intervertebral discs with complex structure and mechanical properties was modeled using spring element that compensate stiffness and tube-to-tube contact element was employed to give follower load. Performing geometrical non-linear analysis. Results: The differences of intervertebral disc L4-5 behavior under the follower compression load in comparision with vertical compression load are as follows. Conclusion: As a result of finite element interpretation of instrumented lumbar spine, the stability of L4-5 sustaining fused lumbar segment, the long level fused lumbar spine observed hing stability under follower load. This research method can be the basis tool of effects prediction for instrumentation, a invention of a more precious finite element interpretation model which consider the role of muscle around the spine is loaded.

• Korean Journal of Psychosomatic Medicine
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• v.20 no.2
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• pp.91-97
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• 2012

Objectives : With the increase in cancer prevalence, the health behavior of cancer survivors has become an important issue. This study was conducted to examine the psychosocial correlates of behavior changes after cancer diagnosis. Methods : 95 patients completed questionnaires assessing depression, anxiety, insomnia, posttraumatic stress symptoms, social constraints, personal beliefs about cancer cause and health-related behavior changes after cancer diagnosis. Results : In the multiple logistic regression analysis, insomnia was the only significant predictor of positive change in physical behavior : normal sleep group(Odds ratio=9.462, 95% CI 1.738-51.509) and subthreshold insomnia group(Odds ratio=10.529, 95% CI 1.701-65.161) showed a larger increase compared to the insomnia group. In psychosocial behavior, low age, religion and causal belief in hormonal factors were independent factors that predicted increase in positive change. Conclusions : This study showed a difference between predictors of physical and psychosocial health behavior change after breast cancer diagnosis. Multi-faceted approaches are required to promote positive change in health behavior in cancer patients.

• Journal of Navigation and Port Research
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• v.44 no.1
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• pp.44-52
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• 2020

More accurate forecasting of port cargo in the global long-term recession is critical for the implementation of port policy. In this study, the Busan Port container volume (export cargo and transshipment cargo) was estimated using the Vector Autoregressive (VAR) model and the vector error correction (VEC) model considering the causal relationship between the economic scale (GDP) of Korea, China, and the U.S. as well as ARIMA, a single volume model. The measurement data was the monthly volume of container shipments at the Busan port J anuary 2014-August 2019. According to the analysis, the time series of import and export volume was estimated by VAR because it was relatively stable, and transshipment cargo was non-stationary, but it has cointegration relationship (long-term equilibrium) with economic scale, interest rate, and economic fluctuation, so estimated by the VEC model. The estimation results show that ARIMA is superior in the stationary time-series data (local cargo) and transshipment cargo with a trend are more predictable in estimating by the multivariate model, the VEC model. Import-export cargo, in particular, is closely related to the size of our country's economy, and transshipment cargo is closely related to the size of the Chinese and American economies. It also suggests a strategy to increase transshipment cargo as the size of China's economy appears to be closer than that of the U.S.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.562-568
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• 2017

A precast floating slab track with a 5m slab panel and installed with isolators is proposed to solve the noise and vibration problem at existing elevated railway stations. Thus, the construction can be carried out rapidly without interrupting the train operation. However, dynamic instability problems may be caused by repeated discontinuities in track due to the short slab panel length and excessive rail displacement due to the inherent operation mechanism of a floating system in reducing the vibration. Furthermore, the difference of the supporting stiffness at the transition between the floating track and ballast track may raise problems. In this study, the assessment factors to evaluate the dynamic stability of the precast floating slab track are presented and assessed with the vehicle-track interaction analysis. Through the analysis, all values relevant to the stability at the floating track section are found to be acceptable, and the slab panels at the transition section are designed to satisfy the stability.

• Journal of Korea Port Economic Association
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• v.26 no.3
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• pp.114-129
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• 2010

Busan port's main function is handling container cargo compared to world major ports and the percentage of handling general cargo such as dirty bulk cargo is very low. In other words, although total cargo weight of Busan port that recorded the handling result of 13.29million TEU in 2008 reached 113.05million ton, total cargo weight of general cargo was 15.31million ton, so container cargo accounted for 88.1% of whole cargo weight. However, it is the time to create high added value by the increase of handling and marketing dirty bulk cargo. Originally, the dirty bulk cargo was not the avoided object from the first. Somehow, it is a very high added value cargo, and is surely essential strategic material to basic industries of nation. However, it becomes dirty bulk cargo as the companies are reluctant to handle it because of environmental problem, distinct characteristic in handling, uncertain break even point due to imbalance between supply and demand compared to container cargo. However, items that are classified as dirty bulk cargo now are certainly necessary strategic materials to national basic industries or national life. Besides it seems to be a high added value cargo here and now. Therefore, it is time that increasing of handling dirty bulk cargo by marketing it and the system for efficient handling such as constructing the exclusive use wharf in Busan port, modernizing of facilities and equipments, stable secure of place for holding and handling through development of distribution complex by item, efficient data processing and closer cooperation by setting up a SCM of related authorities are needful.

• Journal of The Korean Association For Science Education
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• v.11 no.2
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• pp.161-178
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• 1991

This study was designed to investigate the effect of test anxiety, intelligence, and item arrangement order on test performance in Earth Science. The main purposes in this study were to investigate (1) (2) (3) (4) on test performance.: (1) the effect of test anxiety components on test performance in Earth Science. (2) the effect of item arrangement order on test performance in Earth Science. (3) the effect of test anxiety This study was designed to investigate the effect of test anxiety, intelligence, and item arrangement order on test performance in Earth Science. The main purposes in this study were to investigate (1) (2) (3) (4) on test performance.: (1) the effect of test anxiety components on test performance in Earth Science. (2) the effect of item arrangement order on test performance in Earth Science. (3) the effect of test anxiety components on test performance in Earth Science according to learner's intelligence levels. (4) test effect of item arrangement order on learner's intelligence. The hypothesis was that there is difference among test achievements scores according to (1) test anxiety-worry levels. (2) item arrangement orders. (3) item arrangement orders on test anxiety-worry levels. (4) test anxiety-worry levels on intelligence levels. (5) test anxiety-emotionality levels. (6) item arrangement orders on test anxiety-emotionality levels. (7) test anxiety-emotionality levels on intelligence levels. (8) item arrangement orders on intelligence levels. The test items selected for this study were derived from the text Science (part 1) first grade of high school. The subjects of this study were 164 of high school first grade boy students in Pusan. They were assigned to one of the three groups, according to test anxiety levels.: (1) upper 25% of total subjects designated to high group (2) middle 50% (3) low group, lower 25% of total subjects And according to LQ. (1) upper 25% of total subjects designated to high group. (2) middle 50%. (3) low group, lower 25% of total subjects Analysis of variance was used in this study for hypothesis examination. The dependent variable was the achievement scores of Earth Science test and independent variables were test anxiety(worry, emotionality) level, LQ. level, item arrangement orders. The principal findings of the present study are as follows: (1)Test achievement score trend decreases as the test anxiety (worry, emotionality) increases although the result is not statistically significant. (2)There is no significant difference among test achievement scores according to item arrangement orders. (3)The higher the LQ. is, the more effective test anxiety. And the LQ. has significant interaction effect with test anxiety. (4)There is significant interaction effect between the LQ. levels and itemqr arrangement orders.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.1
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• pp.49-54
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• 2006

The recent fingerprint recognition system has unstable factors, such as copy of fingerprint patterns and hacking of fingerprint feature point, which mali cause significant system error. Thus, in this research, we used the fingerprint as the main recognition device and then implemented the multi-biometric recognition system in serial using the speech recognition which has been widely used recently. As a multi-biometric recognition system, once the speech is successfully recognized, the fingerprint recognition process is run. In addition, speaker-dependent DTW(Dynamic Time Warping) algorithm is used among existing speech recognition algorithms (VQ, DTW, HMM, NN) for effective real-time process while KSOM (Kohonen Self-Organizing feature Map) algorithm, which is the artificial intelligence method, is applied for the fingerprint recognition system because of its calculation amount. The experiment of multi-biometric recognition system implemented in this research showed 2 to $7\%$ lower FRR (False Rejection Ratio) than single recognition systems using each fingerprints or voice, but zero FAR (False Acceptance Ratio), which is the most important factor in the recognition system. Moreover, there is almost no difference in the recognition time(average 1.5 seconds) comparing with other existing single biometric recognition systems; therefore, it is proved that the multi-biometric recognition system implemented is more efficient security system than single recognition systems based on various experiments.