• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5D
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• pp.499-505
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• 2012

As the excavation depths during excavation works in urban sites are getting deeper and bigger, It is necessary to study for the improvements to solve the problems in the excavation processes. This research deals with the excavation method that can not only minimize the effect on the surrounding constructions, but also shorten the construction period of the excavation work. For this research, there have been an extensive literature review of the bibliographic data about Slurry Wall Method, which is recognized around the world, and the analysis of the major problems in the existing ineffective construction step. These efforts led to the technical improvements. Accordingly, a new construction method applied with the new technical factors has been suggested, and it was possible to compare Slurry Wall Method with the construction method and analyze them on the base of the examples using the suggested method. This new method decreased the excavation period by 15 days. It took only 33days to finish the excavation work, as compared to 48 days that can be seen on the pre-modification schedule. Furthermore, the suggested method in this research is safer, more economically feasible, and better for the environment than Slurry Wall Method. It will contribute to shortening the construction period of Slurry Wall Method in the end.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.329-334
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• 2017

The structures, which are made up with the huge number of degrees-of-freedom and the assembly of substructures, have a great complexity. In order to increase the computational efficiency, the analysis models have to be simplified. Many substructuring techniques have been developed to simplify large-scale engineering problems. The techniques are very powerful for solving nonlinear problems which require many iterative calculations. In this paper, a modal derivatives-based model order reduction method, which is able to capture the stretching-bending coupling behavior in geometrically nonlinear systems, is adopted and investigated for its performance evaluation. The quadratic terms in nonlinear beam theory, such as Green-Lagrange strains, can be explained by the modal derivatives. They can be obtained by taking the modal directional derivatives of eigenmodes and form the second order terms of modal reduction basis. The method proposed is then applied to a co-rotational finite element formulation that is well-suited for geometrically nonlinear problems. Numerical results reveal that the end-shortening effect is very important, in which a conventional modal reduction method does not work unless the full model is used. It is demonstrated that the modal derivative approach yields the best compromised result and is very promising for substructuring large-scale geometrically nonlinear problems.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.743-749
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• 2010

The present study was conducted to evaluate the effects of resistant starches (RS2, RS3) on weight change and defecation states in rats with constipation induced by loperamide. Sixty male Sprague-Dawley rats were divided into the following six groups: normal control-5% cellulose (NC), constipated-5% cellulose (CC), constipated-5% pectin (CP), constipated-5% RS2 (CR2), constipated-8% RS2 (CR2-H) and constipated-5% RS3 (CR3). The animals were fed AIN76-based experimental diets for 5 weeks. Supplementation of RS2 and RS3 resulted in significantly lower feed efficiency ratios and body weight gain as compared to cellulose supplemented group. Large intestine length was significantly longer in the resistant starch and cellulose groups than in the pectin group. Relative fecal weight to feed intake was significantly higher in the RS3 resistant starch group than in the pectin group, and the appearance of feces was similar to that of the cellulose group. Supplementation of RS3 or cellulose significantly shortened gastrointestinal transit time in the constipated rats as compared to pectin. The results of the present study demonstrated that resistant starch supplementation, especially RS3, may help in depress body weight gain and alleviate constipation through an increase of fecal weight and shortening gastrointestinal transit time in constipated animals.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.184-191
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• 1989

The effect of various supplementary light sources on the agronomic characteristics has been investigeted for generation acceleration of barley in green house with the condition of 15$^{\circ}C$ and 8 hrs. day light followed by each supplementary light sources including incandescent electric lamp (IN), Blue fluorescent lamp(BF). day-light fluorescent lamp(DF), Biolux lamp(BL), BL+BF, In+BF and IN+BL. Leaf number of main stem, leaf area, culm length, dry matter yield of shoot, number of grain per spike, grain yield per plant were most sharply decreased with the exposition of IN, while flag-leaf emergence on main stem and I, 000 grain weight were earlist and heavist respectively with the exposition of IN. In appeared to be best light source for shortening the days to heading, but IN + BF will be most desirable light source with considering both days to heading and adequate yield at the same time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6274-6281
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• 2015

Radio-based train control system has driving headway shortening effect by real-time train interval control using two-way radio communication between onboard and wayside systems, and reduces facility investment because it does not require any track-circuit. Automatic train protection(ATP), the most significant part of the radio-based train control system, makes sure a safe distance between preceding and following trains, based on real-time train location tracing. In this paper, we propose the overall ATP train interval control algorithm to control the safe interval between trains, and preprocessing-based speed profile calculation algorithm to improve the processing speed of the ATP. The proposed speed profile calculation algorithm calculates the permanent speed limit for track and train in advance and uses as the most restrictive speed profile. If the temporary speed limit is generated for a particular track section, it reflects the temporary speed limit to pre-calculated speed profile and improves calculation performance by updating the speed profile for the corresponding track section. To evaluate the performance of the proposed speed profile calculation algorithm, we analyze the proposed algorithm with O-notation and we can find that it is possible to improve the time complexity than the existing one. To verify the proposed ATP train interval control algorithm, we build the train interval control simulator. The experimental results show the safe train interval control is carried out in a variety of operating conditions.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.733-736
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• 2009

Power Line Communication(PLC) is need not additional communication line. So establishment expense is inexpensive and application is simple. Therefore, lower part network of various application field is possible. However, there are high subordinate interference and noise problem on limited transmission data and communication interference element. Wireless Sensor Network(WSN) is need not infrastructure, Self-regulating network architecture of sensor nodes is possible. So at short time, network construction is available. But, power consumption is increased by active sensing for QoS elevation and unnecessary information transmission, low electric power design and necessity of improve protocol are refered to life shortening problem and is studied. In this paper, supplement problem of power line communication and wireless sensor network mutually and because advantage becomes linkage integration control system using synergy effect of two technologies as more restriction be and tries to approach structurally control network that is improved for smooth network environment construction. Honeywell's hybrid sensor network does comparative analysis(benchmarking). Confirm performance elevation proposing teaming of power line communication and wireless sensor network. Through simulation, service delay decreases and confirms that performance elevation.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.6
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• pp.503-513
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• 2016

In order to reduce the green-house gas exhaustion, International Maritime Organization (IMO) has been reinforcing carbon gas regulations. Due to the regulations, a lot of competitions for designing Eco ship in the shipbuilding industry are progressing now. It is faced with the necessity of reducing hull weight by combining automated systems for optimal compartment arrangement with hull structural design. Most researches on optimum structural design method have been consistently in progress and applied to minimize weight and cost of mid-ship section in preliminary ship design stage based on analytical structural analysis method on fixed compartment arrangement. In order to reduce design period and to improve international technical competitiveness by shortening the period of hull structural design and enhancing design accuracy, it has been felt necessity to combine optimized compartment arrangement with optimum design of ship structure based on the international regulations and rules. So in this study, the automated design algorithm for longitudinal members has been developed to combine automated algorithm of compartment arrangement with hull structural design system for oil tanker. The SeaTrust-Hullscan software developed by Korean Register is used to perform ship structural design for mother ship and selected design cases. The effect of weight reduction is verified with comparison of ship weight between mother ship and the cases suggested in this study.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.1
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• pp.3-8
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• 2016

Functional dyspepsia is one of the most common bowel disorders as prevalent of 7.7% Korean population. The cardinal manifestations include bothersome postprandial fullness, early satiation, epigastric burning or pain. These features are chronic and should be presented recurrently with no other compatible organic disease to explain the symptoms. Even though it is not life-shortening, functional dyspepsia usually make the health-related quality of life worse especially if other functional bowel disorder coexist. The coexistence of functional bowel disorders is called as 'overlap syndrome'. Anxiety, somatization and insomnia is more prevalent in overlap syndrome compared with sole functional bowel disorder. Therefore, it is worthwhile that physician interviews and elucidates whether the dyspeptic patient had other kinds of functional bowel disorders, and manages the underlying psychotic pathology. Placebo effect is large in functional dyspepsia, and there is only four kinds of prokinetics that is proven to be superior to placebo. Adverse events relating prolonged administration of prokinetics sometimes fatal or irreversible, physician willing to describe prokinetics should be familiar to the possible adverse effects and the relating risk factors. Pathologic acid reflux is not uncommon in functional dyspepsia, and acid-suppressant is equivalent to the prokientics in most of dyspeptic patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.160-166
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• 2021

In this study, we aim to develop a scenario for educational utilization of disaster response robots that can be used at fire sites and analyze the effectiveness of scenarios according to robot utilization education. Our scenarios were developed based on direction, reality, and rationality determined through the use of a questionnaire survey distributed to current firefighters. In addition, the educational utilization of disaster response robots and training effectiveness were analyzed through repetitive robot control training by a robot development team, current firefighters, and college students. Robot control was divided into direct control, monitor control, and simulation control, and tests were carried out five times. As a result of the analysis of the robot control test, the average time spent for each group was 28 seconds for college students, followed by development teams (30second) and incumbent firefighters (38second). According to the individual analysis results, firefighters (maximum 35second) in direct control, the development team (maximum 14second) in monitor control, and firefighters (maximum 22second) in simulation control showed the effect of shortening control time. These results show that robot control education and training is necessary for robots to be used more effectively at disaster sites.

• Korean Journal of Labor Studies
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• v.17 no.1
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• pp.37-70
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• 2011

The 40-hour work week system has brought positive impact on shortening working hours, eliminating long-time work, increasing leisure-time with family, etc. And this has brought about an increase in leisure-life satisfaction and happiness level. The type of leisure activities has changed from passive activities such as rest to active activities such as sports, tourism. And the 40-hour work week system has positive impact on social activities such as participation in volunteer work and, club activities. Thus all efforts need to be made to establish 40-hour work week system as soon as possible in all workplace. Firstly, 40-hour work week system needs to be introduced to every workplace with less than 5 persons, enlarge 5-day school week system into every primary and secondary school, and create conditions for positive leisure activities. Secondly, labor standards supervision and administration needs to be strengthened to eliminate long-time work over 52 hours per week, below-minimum wage work.