• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.179-190
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• 2011

The swirling flow developing in Francis turbine draft tube under part load operation leads to pressure fluctuations usually in the range of 0.2 to 0.4 times the runner rotational frequency resulting from the so-called vortex breakdown. For low cavitation number, the flow features a cavitation vortex rope animated with precession motion. Under given conditions, these pressure fluctuations may lead to undesirable pressure fluctuations in the entire hydraulic system and also produce active power oscillations. For the upper part load range, between 0.7 and 0.85 times the best efficiency discharge, pressure fluctuations may appear in a higher frequency range of 2 to 4 times the runner rotational speed and feature modulations with vortex rope precession. It has been pointed out that for this particular operating point, the vortex rope features elliptical cross section and is animated of a self-rotation. This paper presents an experimental investigation focusing on this peculiar phenomenon, defined as the upper part load vortex rope. The experimental investigation is carried out on a high specific speed Francis turbine scale model installed on a test rig of the EPFL Laboratory for Hydraulic Machines. The selected operating point corresponds to a discharge of 0.83 times the best efficiency discharge. Observations of the cavitation vortex carried out with high speed camera have been recorded and synchronized with pressure fluctuations measurements at the draft tube cone. First, the vortex rope self rotation frequency is evidenced and the related frequency is deduced. Then, the influence of the sigma cavitation number on vortex rope shape and pressure fluctuations is presented. The waterfall diagram of the pressure fluctuations evidences resonance effects with the hydraulic circuit. The influence of outlet bubble cavitation and air injection is also investigated for low cavitation number. The time evolution of the vortex rope volume is compared with pressure fluctuations time evolution using image processing. Finally, the influence of the Froude number on the vortex rope shape and the associated pressure fluctuations is analyzed by varying the rotational speed.

• The Journal of Korean Medicine
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• v.39 no.3
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• pp.41-50
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• 2018

Objectives: The study is aimed to utilize Taesikbub and Lung-doyinbub described in "Dong-Ui-Bo-Gam" as a Korean Traditional Pulmonary Rehabilitation Exercise. Methods: We preliminary researched pulmonary rehabilitation exercise using domestic and international databases and old literatures of Korean Medicine. Then made a draft of Korean Traditional Pulmonary Rehabilitation Exercise based on "Dong-Ui-Bo-Gam". After organizing expert group for verifying the draft of the exercise, we developed the final Korean Traditional Pulmonary Rehabilitation Exercise. Results: The Korean Traditional Pulmonary Rehabilitation Exercise is composed of 5 actions including breathing method, flexibility exercise, percussion and hitting teeth. This exercise is recommended twice a day for at least 5 days per week under the supervision of specialist. It is expected to improve physical activity, dyspnea, health-related quality of life (HRQoL) as well as psychiatric symptoms by breathing deep and slow and exercising the thorax and upper limb muscles. Conclusion: Taesikbub, Lung-doyinbub in "Dong-Ui-Bo-Gam" may be suggested as a better pulmonary rehabilitation exercise for patients of chronic lung disease.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.40
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• pp.97-144
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• 2008

The purpose of this paper is to review the text of national legislation relating to the carrier's liability in respect of the carriage of passengers, baggage and cargo by air in major states such as United Kingdom, Germany, France, Canada, Russia and China, and to compare the air carrier's liability under the national legislations of above states with them under the Warsaw System relating to the international carriage by air. Also this paper reviews the text of the draft legislation relating to the carrier's liability in respect of the carriage by air in Korea. The Warsaw Convention for the Unification of Certain Rules Relating to International Carriage was adopted in 1929. In 1999, the ICAO adopted the Montreal Convention for the Unification of Certain Rules for International Carriage by Air vastly modernizing the unification of private air law. The Montreal Convention replaced the instruments of the “Warsaw System”, and came into force on 4 November 2003. The Montreal Convention is not only an international convention. It has also exercised a considerable influence on national legislation. A the Convention, or certain of its principles, with the object of regulating their national air transport. The main feature of the liability regime of the air carrier under the Montreal Convention is the two-tier liability system for death or injury of the passenger with strict liability up to 100,000 SDR and presumptive liability with a reversed burden of proof without any limit above that threshold. The principles of the liability of the air carrier under the Montreal Convention have been adopted into national legislations by the United Kingdom, Germany, France, Canada, Russia and China. Now the Ministry of Justice of Korea is proceeding to make a new national legislation relating to the liability of the air carrier in respect of the carriage by air. The draft legislation of the Part VI the Carriage by Air of the Commercial Code of Korea has adopted the main principles of the liability of the air carrier under the Montreal Convention. In conclusion, the national legislation relating to the liability of the air carrier in Korea will contribute to settle efficiently the dispute on the carrier's liability in respect of the carriage of passengers, baggage and cargo by air.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1207_1208
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• 2009

It is expected that standardized framework for urban rail transit system will contribute to more convenient and safe traffic service and ensure higher reliability and availability of urban rail transit rolling stock and infrastructure. Information and telecommunication system in urban rail transit consists of various subsystems, such as radio communication system, digital transmission system, integrated monitoring system and public addressing system and its standardization will be implemented based on these subsystem. Public addressing system is to provide information related to operation and emergency for passengers and operators. In this paper we suggest draft criterion of public addressing system for urban rail transit through functional analysis and comparison on the present state of the system.

• Fibers and Polymers
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• v.7 no.4
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• pp.424-431
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• 2006

Roll drafting, a mechanical operation attenuating fiber bundles to an appropriate thickness, is an important operation unit for manufacturing staple yams. It influences not only the linear density regularity of the slivers or staple yams that are produced, but also the quality of the textile product and the efficiency of the thereafter processes. In this research, the dynamic states of the fiber bundle in the roll drafting zone were analyzed by simulation, based on the mathematical model that describes the dynamic behavior of the flowing bundle. The state variables are the linear density and velocity of the fiber bundles and we simulated the dynamics states of the bundle flow, e.g., the profiles of the linear density and velocity in the draft zone for various values of the model parameters and boundary conditions, including the initial conditions to obtain their influence on the dynamic state. Results showed that the mean velocity profile of the fiber bundle was strongly influenced by draft ratio and process speed, while the input sliver linear density has hardly affected the process dynamics. Velocity variance of individual fibers that could be supposed to be a disturbing factor in drafting was also influenced by the process speed. But the major disturbance occurred due to the velocity slope discontinuity at the front roll, which was strongly influenced by the process speed. Thickness of input sliver didn't play any important role in the process dynamics.

• Journal of the Korean Society of Costume
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• v.36
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• pp.139-148
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• 1998

In order to know what sorts of features of neck form may be required to make plans for tight collars, the neck form of young japanese women were measured three demension-ally using GRASP(Grating Projection System for Profiling) and plaster torso. By the BASIC language in NEC computer and EXCEL program in MACINTOSHI computer, it became possible to draft a number of neck surface auomatically, therefore, we got analysis of a mass of subjects. Thed following results were obtained: 1. There was a large individual difference in the shape of neck, in particular, on the front and side curves of the neck base line, where the undulation of clavicular part of neck and inclination of shoulder are refracted. 2. When designing a stand collar, from the viewpoint of clothing strcture, it is important to grasp exactly the shapes of the neck, such as the line of the neck base, the neck gradient, back neck length, back neck width & girth. 3. According to the somatotypes(turing-over, standard, bending type), there were different the method of the basic collar pattern making.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.7 s.238
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• pp.868-877
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• 2005

We performed the experimental and the numerical study on the comparison of thermal comfort performance indices for cooling loads in the lecture room for 4 cases: Fan coil unit(FCU) or 4-way cassette air-conditioner is respectively operated with the ventilation system or without. We measured the velocity, the temperature distribution and predicted mean vote(PMV) value in the lecture room for 4 different air-conditioning methods. Effective draft temperature(EDT) and PMV were investigated to analyze the characteristics of two thermal comfort indices in the lecture room and to compare their values each other. From the results we knew that there is the similarity between PMV values and EDTs when the room is air-conditioned for cooling loads. It turned out that definition of the control temperature is very important when the EDT is calculated. Finally EDT should not be used to predict the accurate thermal comfort in case that the temperature and humidity are suddenly varied and the zone affected by the solar and inner wall radiation.

• Journal of Energy Engineering
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• v.18 no.4
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• pp.258-263
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• 2009

Jet Loop Reactor(JLR), in which a two-phase nozzle is installed, is the new design technique for the treatment of high concentration wastewater by accelerating of oxygen contacting between substrate and surrounding bacteria. This numerical study of the two phase jet flow was conducted to find the optimum design of JLR. It was shown that there was a minimum velocity in the nozzle for continuous circulation of wastewater. The optimum location and the size of the draft tube for continuous circulation were examined. It was certain that the smaller the air size is, the more the effect of the mixing increases. The relation between the mixing effect and the turbulence was confirmed.

• The Korean Journal of Air & Space Law and Policy
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• v.15
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• pp.40-66
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• 2002

The purpose of this paper is to investigate the legal controㅣ, by using the International Criminal Court(ICC) that will enter into force to the most serious crimes of concern to the international community as a whole, and regulates the jurisdiction with respect to the following crimes: (a) The crime of genocide; (b) Crimes against humanity; (c) War crimes; Cd) The crime of aggression. However, the existing ICC Statute excludes (e) Crimes, established under or pursuant to the treaty, which was regulated by the ICC draft statute that the International Law Commission(ILC) examined and submitted to the UN General Assembly in 1994, and which contained aircraft terrorism such as hijacking in the Hague Convention of 1970 or sabotage in the Montreal Convention of 1971 in Annex of ILC draft. Therefore, this paper examines the legal character of aircraft terrorism as one of the most serious crimes of concern to the international community as a whole, and suggests two kinds of legislative comments for the amendment of the ICC Statute including aircraft terrorism as an object of the jurisdiction of the Court, for suppressing aircraft terrorism in advance and ensuring equitable penalty by ICC system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.6
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• pp.1357-1366
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• 2015

This study (II) aims to draw up the future-oriented construction policy recommendations based on the outcomes as a result of a broad research and conducting questionnaire surveys on the arguable issues raised by construction engineers for roads and bridges in the course of previous study (I) implementation. As for the question of "The term 'Construction Management (CM)' which currently is defined in two (2) ways", 45% of respondents have answered that two (2) different types of CM should be unified into one (1) CM type as is the case in most advanced countries. About the question of "The ways to educate the CM professionals", many respondents have preferred to acquire CM professional certificate after receiving education for a certain period of time from private CM training institutions. As for the question of The revised draft that the ICEC grade of special engineers for design, construction and quality control areas shall be "more than 78 points from a more than 75 points by the original draft." 52% of respondents preferred to maintain the original draft. About the question of "The reason why the CM system has not been working well yet." 62% of respondents have answered that the staff members who are in charge of handling public project procurements are concerned about the fact that their roles (or activities) might be deprived as a result of CM adoption. In order for the CM system to be activated, based on the notion that the construction projects must be out soured, the reshuffle of the headquarter organization of Ministry of Land, Infrastructure and Transportation (MLIT) should be preceded.