• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.6
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• pp.265-271
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• 2013

Czochralski (CZ) growth process is one of the most important techniques for growing high quality sapphire single crystal for LED application. In this study, the inductively-heated CZ growth processes for the sapphire crystal of 300 mm length have been analyzed numerically using finite element method. The hot zone structures were modified with the crucible geometry change and the additional insulation layer installed above the crucible. The results show that the solid-liquid interface height decreased from about 80 mm at initial stage to 40 mm after mid-stage due to achieve the growth speed balance. Also the optimal input power of the modified system was similar with the original one due to the compensation effects of the crucible geometry and additional insulation. The crystal temperature grown by the modified CZ grower was increased about 10 K than the original one. Therefore the sapphire crystal of 300 mm height was grown successfully.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.3
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• pp.38-51
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• 2020

A bottleneck and congestion occur when a freeway is closed due to maintenance and construction activities on the freeway. Although various traffic managements have been developed to improve the traffic efficiency at freeway work zones, such as merge control, there is a limit to those controls with human drivers. On the other hand, the wireless communication of connected and automated vehicles (CAVs) enables the operation of advanced traffic management. This study developed a traffic control strategy that integrates Dynamic Merge Control (DMC) and Lane Change Control (LCC) in a CAV environment. DMC operates as an either early or late merge based on the occupancy rate of upstream of the work zone. The LCC algorithm determines the number of vehicles that need to change their lane to balance the traffic volume on open lanes. The simulation results showed that integrated control improves the cumulative vehicle count, average speed upstream, and average network travel time.

• Therapeutic Science for Rehabilitation
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• v.9 no.2
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• pp.7-25
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• 2020

Objective : The purpose of this study was to analyze the effects of dual-task training on stroke patients. Methods : We searched the databases such as NDSL, RISS, PubMed, CoChrane and EMBASE for publications in the past decade. Finally, 10 papers were selected. Qualitative assessment was performed according to the traditional single-layer evidence model, and meta-analysis was performed using the Comprehensive Meta Analysis 3.0 program. Results : The quality level of each of the 10 selected papers all correspond to I and II in the traditional single-layer evidence model. The motor tasks that constitute dual-task training comprised walking or balancing tasks in 7 articles and the motor tasks related to upper extremity were selected in 3 studies. The effect sizes for ADL function and Cognitive function were 0.65 and 0.64 (medium size effect) respectively. Moreover, the effect sizes of Lower extremity and Upper extremity motor function were 0.34 and 0.22 (small size effect) respectively. The effect size of ADL function and Cognitive function were statistically significant p<0.05). Conclusion : This study confirmed that dual-ask training can be a useful intervention technique for recovering a stroke patient's ability to perform daily activities and cognitive functions. This could be used as a helpful data when selecting appropriate intervention for stroke patients in the clinical setting.

• Korea and Global Affairs
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• v.2 no.2
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• pp.5-40
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• 2018

The history of decentralization and autonomy is the result of the struggle for democracy against the authoritarian central government. Before the imminent law amendment, there are many tasks for decentralization and citizen autonomy. Therefore, decentralization and autonomy are not given on their own but they must be taken from authoritarian and centralist power group which possesses exclusive interests. The decentralization and autonomy now enters into the stage of development. In 1960, the April 19 Revolution opened the era of democratic local autonomy and it was abolished by the military coup of May 16, Now, the era of the reform of the decentralization are coming. Decentralization and autonomy will evolve from the stage of quantitative expansion to the stage of qualitative leap. This paper proposes that the revision of decentralization be the strategic maximum, and that the independence of the local government personnel rights be the tactical minimum. This paper insists that the independence of personnel right in the local government can be a link with law amendment for decentralization. Local autonomy and decentralization are the main subjects of the amendment. Above all, clarifying this is the subject and method of this study, and the scope of the study.

• Korean Business Review
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• v.21 no.2
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• pp.195-214
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• 2008

In 2004, in order to create core competences and major growth drivers for endogenous regional developments, the Korean government adopted the policies for establishing regional innovation systems, The main organization for the policies is the regional innovation council which is composed of diverse groups of scholars, professionals, and government officials. The regional innovation council of Kang-won Province consists of a couple of sub-divisions such as Operation Committee, Administration Office, Planning and Moderation Department, Strategic Industry Department, Culture and Tourism Industry Department, Regional Industry Department, and Regional Human Resource Development Department. The primary roles and jobs are planning, reviewing, evaluating and finalizing regional innovation policies. However, because of conflicts with local government, insufficient budget problems, organization structure problems, and decision making process problems, the regional innovation councils could not perform their original roles and functions. They could not adopt radical or non-traditional strategies. Although it's failure, a lot of people recognize the importance of regional innovation councils' roles and functions, I believe there would be another regional innovation councils coming continuously which would be take more important roles and have more power over budgeting problems. The purpose of this article is to identify the primary sources of strategies and organization structure problems of the previous regional innovation councils and to provide a couple of answers. In this paper, the author primarily analyze the problems of the Kang-won innovation council. A couple of answers to the desirable organization structures and the desirable roles of regional innovation councils will be presented for discussion.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.3
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• pp.321-330
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• 2011

We experimentally investigated the effect of applied DC electric fields on the flame spread over polyethylene-coated electrical wire. The flame-spread rates over electrical wire with negative and positive DC electric fields from 0 to ${\pm}7$ kV were measured and analyzed. We compared the results for DC electric fields with previous results for AC electric fields. We explored whether or not various flame shapes could be obtained with DC electric fields and the main reason for the flame-spread acceleration, particularly at the end of the electrical wire, for AC electric fields. We found that DC electric fields do not significantly affect the flame-spread rates. However, the flame shape is mildly altered by the ionic wind effect even for DC electric fields. The flame-spread rate is relevant to the flame shape and the slanted direction in spite of the mild impact. A possible explanation for the flame spread is given by a thermal-balance mechanism and fuel-vapor jet.

• Journal of Nutrition and Health
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• v.2 no.4
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• pp.143-153
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• 1969

For the purpose of the better dietary management and to emphasize of importance in nutrition education for 949 woman workers at the dormitory of wig factory in Seoul, the nutritional survey was conducted for seven days from August 13 th to 20 th of 1969. The survey included food and nutrient intakes, physical measurement, clinical findings and biochemical measurement were conducted for the randomly sampled 44 subjects. According to the survey results, their heights was under the standard and the 82% of the total subjects was the age ranges from 16 years to 20 years old. Their daily menu was not planned properly and the concept of 5 basic food groups was not utilized in their menu planning. The balanced meal should be emphasized in this factory. Calories and protein intakes are low compared with the recommended allowance and especially animal protein intake is low. Fat intake is only 8.8 grams for capita per day. Vitamins and minerals intake are also low. Clinical and biochemical survey indicated various vitamin deficiencies and anemia which is mostly due to the iron insufficiency.

• Journal of the Korean earth science society
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• v.40 no.6
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• pp.654-670
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• 2019

From the perspective of science gifted education, the successful intelligence theory is a means to understand how the gifted education curriculum reflects the characteristics of science gifted students. The purpose of this study is to investigate if the successful intelligence is fully reflected in the teaching materials of two gifted education centers (GECDOE: Gifted Education Center affiliated with District Office of Education, GSEIU: Gifted Science Education Institute attached to University). For this study, we selectively used 143 (GECDOE) and 134 questions (GSEIU) from the teaching materials of two gifted education centers. Those questions is analyzed through the semantic network analysis method. The results are as follow. First, the teaching materials of two gifted education centers are not evenly reflected in the successful intelligence, such as analytical ability, creative ability, and practical ability. Second, the teaching materials of two gifted education centers intensively demands analytical ability for students such as 'identify problem', 'represent and organize information', and 'additional prompts for analytical thinking'. Third, the teaching materials of two gifted education centers are presented to students without linking each frame of successful intelligence to one another. As the gifted students are quick to learn and show a preference for more complex thinking, it is necessary to develop teaching materials to experience the various abilities and promote integrated thinking according to the level of the gifted students. In this respect, this study is expected to be used as useful information for developing teaching materials to support customized education for gifted students.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.4
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• pp.153-171
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• 2011

The welfare system and the direction of the welfare policy have been unable to escape greatly from the frame of the past against the facts that the external environments of the national economy of the world including Korea have been changing in quick and rapid speed. Such results have caused the issues related with the welfare, economy and society ended in the ideological collision in connection with the goals of the policy, the right agreement between the policies lacked, and the intervention and conflict between the interest group concerning the policy continued. Social policy of Korea in the past had the level of complementing the parts which could not be solved through the growth. Employment creation had been achieved continuously backed up by the high rate of growth. And the low aging level, the young population structure, and the high rate of childbirth had been the structures that made such achievement possible. New economic, social and welfare environment at home and abroad has been requesting new change in welfare policy. Goal of the economic and social policy is to construct the safe economic and social system. And what has been requested has been the formation of the economic and social policy orienting the welfare nation in form of social investment and welfare expansion. Also the direction in strengthening the welfare system of Korea shall have the balance between the protection and activation strength with the necessity of converting to the prevention welfare from the post welfare. Also the public part, market, the 3rd sector and the share of the role of an individual shall be achieved. And what is needed is the achievement of the transfer from the paradigm of residual welfare to the universal welfare. And such improvements of the welfare system will be able to elevate the possible continuity of the system in long term basis through the improvement of the welfare system.

• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.357-364
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• 1997

The objective of this study was to find optimum nonionic surfactants for clean up of soils contaminated by hydrocarbon oils. PIT(phase inversion temperature) measurements in ternary systems containing pure hydrocarbons, pure nonionic surfactants, and water were carried out and interfacial tensions were measured as a function of time for n-hexadecane oil drops brought into contact with various mixtures of nonionic surfactant and water. Batch surfactant washing experiments were performed based on the measurement, results of PIT and interfacial tension and the results showed that maximum removal of n-hexadecane occurred at the PIT of the system. For the $C_{12}E_5(C_{12}H_{25}O(CH_2CH_2O)_5H)$ system, maximum n-hexadecane removal of 73.4% occurred at the PIT of $52^{\circ}C$. In contrast, n-hexadecane removal at $25^{\circ}C$ and at $60^{\circ}C$, each corresponding to the conditions of below PIT and above PIT of the system, was found to be 57.1% and 57.0% respectively. The maximum removal of a hydrocarbon at the PIT of a system, where the hydrophilic and hydrophobic properties are balanced, was found to be due to the existence of high oil solubilization into a middle-phase microemulsion and ultralow interfacial of the order of $10^{-2}$ to $10^{-3}$ dyne/cm between middle-phase microemulsion and excess oil phase.