• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.3
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• pp.25-37
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• 2005

For pump-fed rocket propulsion system, the temperature of LOX to be supplied to turbopump inlet should be satisfied with pump inlet temperature requirement during all operating stages, as excessive temperatures can result in cavitation due to reduction in NPSH, thus either damaging the pump or adversely affecting pump performance rise. So exact estimation of LOX temperature rise is absolutely needed for developing reliable propulsion system. This paper presents systematic analysis scheme for estimating inner process of cryogenic propellant tank which is needed for LOX temperature rise. And this paper presents LOX temperature rise and thermal stratification for all rocket operating stages including cooling, filling, waiting, pre-pressurization and firing, with the application of buoyancy driven boundary layer theory.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.356-365
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• 2013

As a form of reciprocity or exchange, gift giving is one of the processes that integrate a society. There has been a long history of research on gift giving behavior in the communication area. Recently with the advent of digital environment, digital contents gift giving behavior became a prevalent social custom. But there has been little research of an individual consumer's consumption behavior of digital contents gift giving. Drawing on the innovation theory, technology acceptance model, and gift giving literature, the author take a quantitative approach to the effect of innovation attributes on mobile coupon gift giving behavior. The result showed that innovation attribute did positive influence to mobile coupon gift giving behavior. Furthermore, consumer innovation attribute moderate in the relationship between product innovation and mobile gift giving attitude.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.401-414
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• 2019

The purpose of this study is to present the results of in-depth analysis of family disintegration experience as a qualitative study to understand the meaning and nature of the experiences of marriage and divorce of women who have divorced in Vietnam. The participants were selected as six Vietnamese women who had been divorced for less than two years after five to 12 years of marriage. The collection of data and the analysis of the data were done by six concrete steps that should be followed in the scientific phenomenology suggested by Colaizzi(1978) Through this study, 74 subjects from 203 semantic meanings were derived and identified as 23 subject groups and finally organized into 7 categories. The seven categories were presented as life in Vietnam before marriage, motive of getting married, method and process of marriage, good experience of marriage, difficult experience in marriage, cause of divorce, changed life after divorce. The results of this study suggest that sexual relationship is a major conflict factor in marriage, and that this problem can lead to divorce. It is hoped that this study will help to find a solution for the dissolution of multicultural families.

• The Journal of the Korea Contents Association
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• v.8 no.8
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• pp.90-102
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• 2008

One of the most distinctive characteristic of the animations of Miyazaki Hayao is appearance of heroines with firm beliefs as well as compassion and generosity.. This study aimed to conduct research into the common points and differences in personality structures targeting <Nausicca of the Valley of WInd>, <Laputa: the Castle in the Sky>, <Mononoke Hime>, and <The Spiriting Away of Sen and Chihiro>, in which heroines appear out of long animation films created and directed by Hayao, In order to analyze the personality types, the study applied the classification criteria of MBTI and enneargram, and it analyzed the personality structures in comprehensive consideration of organic relationships and external characteristics according to the roles of the characters. This study analyzes that their personality type could be created very indivisually by changing their behavior motives, though Miyazaki's heroines are both Savior and idealist. Also, the study defined the characteristics of the personality structures of heroines created by Miyazaki Hayao and prepared data about them based on the results.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1979.05a
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• pp.9.3-9
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• 1979

Foreign bodies in air and food passages are not uncommon problems in the otolaryngological fields and its etiological factors are closely related to the social environment and mode of life. It may complicate of esophageal perforation, periesphagitis, periesophageal abscess, mediastinitis, pneumothorax, pyothorax and lung abscess which may lead to the problems of life and death. The majority of esophageal foreign bodies which lodge in the esophagus can be removed endoscopically, but the following types of foreign bodies may require removal by the external route: 1. an impacted foreign body, 2. a foreign body producing periesophagitis after unsuccessful attempts at removal through the esophagoscope, and 3. a periesophageal abscess with a foreign body lodging in the abscess itself. Many interesting cases and statistical analysis of esophageal foreign bodies were reported by many authors, but only a few complicated cases were reported. Recently, we experienced 2 cases of esophageal foreign bodies which penetrate the cervical and thoracic esophageal wall and formed periesophageal abscess in 12 and 40 years-old males who swallowed of wire accidentally. The foreign bodies are successfully removed by the external routes through the lateral neck and chest. The postoperative courses were uneventful.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.21-32
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• 2016

Baby boomers who were born right after Korea War make up about 15% of population of Korea and lead an aging society rapidly. They're retiring since from 2012 and going to make up nearly 80% of total of old retirees. Baby Boomers with much higher income and education levels are going to enjoy their retirement as traveling. Therefore, this study invests the relationship between lifestyle and travel product selection of baby boomer consumer. Two big results are as follows. One is that baby boomers progress consumption activity(because they have their own purchasing power) and have health and leisure lifestyle and family lifestyle. The other is when they select travel product, they eventually consider three elements- travel company, transportation, and travel colleague.

• Journal of Intelligence and Information Systems
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• v.14 no.3
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• pp.1-23
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• 2008

Nowadays blogging is emerging as a new way of building human-to-human relationship by offering personal information and sharing opinions with others on their own initiatives. These blogging activities would be also useful when people are in a movement surrounding lots of objects, such as products and shops, which are potentially interesting to them. However, immediate response from the objects is not available using legacy blogging systems. This is mainly due to the segregation of the blogging content owners from the objects. This paper, hence, aims to propose a methodology which allows the users to directly communicate with the objects in a timely and context-aware manner, not the object owners, to get useful information or get served immediately. To do so, the concept of artificial bloggers which work on behalf of the objects and eventually the object owners is proposed. The functionalities of u-Blogging are also introduced with prototype system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.5A
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• pp.479-486
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• 2008

In this paper, an efficient training symbol design with m-sequence is proposed for the MIMO-OFDM based next generation wireless transmission system which supports gigabits per second data rate. In the traditional blute force method, the preamble design is based on the case by case comparison with the system requirements. This paper discusses a training symbol design methodology for the MIMO-OFDM system based on the m-sequence which has been widely used in the spread spectrum communication areas due to its good correlation characteristics. Also the step-by-step design and performance verification method within the limited search space is discussed. The proposed method targets the design of the training symbol which satisfies system requirements for the packet based MIMO-OFDM wireless communication system including automatic gain control(AGC), timing synchronization, frequency and sampling offset estimation, and MIMO channel estimation.

• Journal of Digital Convergence
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• v.19 no.10
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• pp.545-554
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• 2021

The purpose of this study was to empirically examine the effects of CSR activities on a defense manufacturing employees' organizational trust and job satisfaction and the mediating effect of organizational trust. To conduct such examinationusing, 289 valid samples collected from field employees of H-company(defense manufacturer) in Chang Won. The empirical analysis results are summarized as follows. First, corporate CSR activities were found to affect job satisfaction of field employees. Second, corporate CSR activities were analyzed to be a very important motivator for field employees. In other words, it can be interpreted that employees who perceive that their organization is actively fulfilling social responsibilities have a high level of perception of organizational trust. Third, it was found that the higher the organizational trust of the employees, the higher the job satisfaction. Fourth, as a result of verifying whether there is a mediating effect of organizational trust in the relationship between corporate CSR activity and job satisfaction, it was found that the full mediating effect and the partial mediating effect were mixed.

• Journal of the Korean Society of International Agriculture
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• v.30 no.4
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• pp.269-276
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• 2018

Achievement of sustainable agricultural development is one of the most important issues in many developing countries. In addition, basic inputs such as labor and capital, and social and environmental factors are important factors in agricultural production in developing countries. This study examines impact of governance conditions of Central Asian newly independent Post-Soviet Union countries on agricultural production and production efficiencies by using World Bank's Worldwide Governance Indicators. The studied countries had similar socio-economic conditions and environments before independence; however, those countries have different forms of development. Empirical results showed that governance improvement helped to increase agricultural production significantly. In addition, we found that each governance factor has different effects on agricultural production. The findings of this study would be a base for sustain agricultural production in developing countries, and stressed the necessity of improved governance conditions as well as input investments for achievement of agricultural development.