• Title/Summary/Keyword: Phase change behavior

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ANNEALING BEHAVIOR OF FeN THIN FILMS

  • Park, S.;Choi, Y.;Jo, S.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.636-640
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    • 1995
  • FeN thin films were deposited on glass by RF diode reactive sputtering. The films were annealed in the air and in vacuum. The film annealed in the air showed sharp decrease of saturation magnetization and change of easy axis direction to hard axis direction and vice versa after $300^{\circ}C$ anneal. The coercivity decreased down to 0.5 Oe after $400^{\circ}C$ anneal. After $450^{\circ}C$ anneal, the film showed ${\varepsilon}-Fe_{2-3}N$ phase. The films annealed in vacuum showed coercivity increase after $300^{\circ}C$ anneal for the film deposited with initial substrate temperature of $35^{\circ}C$ and after $400^{\circ}C$ anneal for the film deposited with initial substrate temperatue of $170^{\circ}C$. These films showed $Fe_{16}N_{2}$ X-ray peaks after $450^{\circ}C$ anneal.

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Numerical Investigation of Urea Freezing and Melting Characteristics Using Coolant Heater (냉각수 순환 가열 방식을 이용한 요소수의 동결 및 해동 특성에 관한 수치적 연구)

  • Lee, Seung Yeop;Kim, Nam Il;Park, Yun Beom;Kim, Man Young
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.8
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    • pp.717-724
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    • 2013
  • Urea-SCR technology is known as one of the powerful NOx reduction systems for vehicles as well as stationary applications. For its consistent and reliable operation in vehicle applications, however, the freezing and melting of the urea solution in cold environments have to be resolved. In this study, therefore, a numerical study of three-dimensional unsteady problems was analyzed to understand the urea freezing and heating phenomena and heat transfer characteristics in terms of urea liquid volume fraction, temperature profiles, and phase change behavior in urea solutions with time by using the commercial software Fluent 6.3. As a result, it was found that the freezing phenomenon proceeds with a phase change from the tank wall to the center, whereas the melting phenomenon occurs faster in the upper part of the storage tank by natural convection and in the adjacent part of the coolant pipe than in other parts. Furthermore, approximately 190 s were required to obtain 1L of urea solution using a 4-coiled coolant heater under conditions of $70^{\circ}C$ and 200 L/h.

Problems Analysis Related to Nutrition and the Development of Nutrition Education Programs for High School Students(II) - A Study Centered on the Development of Nutrition Education Programs for High School Students - (고등학생의 영양 관련 문제점 분석 및 영양 교육 프로그램 개발 ( II ) - 고등학생 대상 영양 교육 프로그램 개발 -)

  • Lee, Eun-Ju;Soh, Hye-Kyung;Choi, Bong-Soon
    • Journal of the East Asian Society of Dietary Life
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    • v.17 no.3
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    • pp.351-363
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    • 2007
  • Previously, we analyzed for nutrition knowledge and the use of nutrition knowledge in the everyday lives of students in order to develop nutrition education programs that focus on desirable behavior change. From this, we found that female students desired to participate in nutrition education more than male students, and regarding their concerns for nutrition education, 73.2% of the females and 50.0% of the males displayed interest in 'obesity and the regulation of body weight'. Therefore, this study showed female students give more attention to the obesity and the regulation of body weight than male students(p=.000<.001). In addition, female students had higher interests($8.63{\pm}1.67$) than male students ($7.45{\pm}2.03$) in nutrition knowledge(p=.000<.001). By investigating the use of nutrition knowledge in everyday life, our research indicated that the actual use of nutrition knowledge was less. To encourage students to persue dietary lives addressing the concerns confirmed above, the following needed to occur. 1) Provide them nutrition information for the main processed foodstuffs encountered when dining out(breads, cakes, cookies, and carbonated beverage). 2) Teach them to read food nutrition labels. 3) Help them find a lifestyle connection through lasting self-management methods and the generation of social support. Accordingly, this required developing effective and practical nutrition education programs that considered regional characteristics and gender differences. The most important factors considered during nutrition education program development were the need for motivation and ongoing education by stage of change, rather than temporal education through specific problem analysis, in order that those being educated may bring about a change of behavior by themselves. Therefore, from this study, we have suggested the use of multilateral operating strategies for successful nutrition education. In addition the phase model of behavior change should be applied. Our programs were aimed at self owned nutritional management so that students could master their own methods for acquiring skills and enjoying dietary life. The research may be summed up as follows. First, the purpose of education at the recognition stage of change was to attempt motivation for nutrition improvement, by analyzing the problems such as food buying habit and the main purchasing viewpoints when dining out. Second, the purpose of education at the action stage of change was to help students acquire of concrete methods for behavior modification by linking the program to their home as well as to teachers with various activities that suited the situation at school. This was done by analyzing the processes and decisions pertaining to dining out the main processed foodstuffs and principal components, etc. through data and experimental practice. Third, the purpose of education for changing of habits and values, or the maintenance stage, was to investigate the various reasons that undesirable behaviors were induced, and then determine a lasting self-management method as well as how to generate social support. If the nutrition education program developed in this study is utilized on site, someone in the primary role as the nutrition educator and trained specifically in nutrition, can help induce the health promotion in the community as well as lasting dietary management, by executing a link with families in parallel with educating teaching staff and students' parents. In addition, this program can playa role in the government policies related to the health promotion for our youth who are the foundation of our nation and who can enhance our national competitive power.

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Pregnant Women's Information Seeking Experience : Structure and Process of Information Seeking (임신부의 정보추구 경험 - 정보추구의 구조와 과정 -)

  • Kim, Kap-Seon
    • Journal of the Korean Society for Library and Information Science
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    • v.40 no.1
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    • pp.13-37
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    • 2006
  • Using Grounded Theory. the present study was to discover structure and process of pregnant women's information seeking experience through identifying concepts and relationships of the experience. In-depth interviews were conducted with 16 Participants selected by theoretical sampling. The findings were : 1) Pregnant womens' information seeking was caused by Acceptance of Pregnancy . 2) The phenomenon of information seeking was for Maintaining Normalcy to Pregnancy(MNP), 3) MNP occurred in connection with Perceived Anxiety and Desire to Know 4) Action/interaction Strategies to MNP were related to the Awareness of Ways Acquiring Information. Previous Knowledge. Self-Regulation, and Information Access Environment. 5) Action/interaction Strategies to MNP were Seeking Diagnostic Data of Antenatal Care. Seeking Standard Knowledge. Seeking Experience. and Seeking Emotional Support. 6) As consequences of taking strategies, pregnant women were experienced in Sufficient. or Insufficient. 7) A three-stage process of information seeking was discovered : Comparing, Contextualising, Making sure. 8) In terms of change of information needs during pregnancy, a four-phasic process was discovered. Acceptance Phase. Adjusted Phase, Focusing Phase, and Transitional Phase. Based upon these results. it needs to generate a substantive theory contributed to holistically explain and predict pregnant women's information seeking behavior.

Assessment of the Effects of Breast Cancer Training on Women Between the Ages of 50 and 70 in Kemalpasa, Turkey

  • Mermer, Gulengul;Turk, Meral
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.24
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    • pp.10749-10755
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    • 2015
  • Background: In both developed and developing countries; breast cancer is the major cancer observed in women. The aim of this study was to assess the effect of nursing and mammographic intervention on women with breast cancer between the ages of 50 and 70. Materials and Methods: A training program, which was quasi-experimental and had a pretest-protest design, was applied in Kemalpaaa district of Izmir, between October 2008 and August 2010. The target population was women between the ages of 50 and 70, who were registered in the list of 3rd Family Medicine Unit in Izmir's Kemalpasa metropolis. A total of 106 women who were in conformity with the study criteria participated in the study. Research data were collected through home visits that included face-to-face interviews; Ministry of Health education material and video films were modified and used for the training. Data analysis was performed through 82 women who were paired at the first and the second phase. Results: It was observed that although the rate of breast self examination significantly increased after the training (p=0.022), the rate of clinical breast examination (p=0.122) and mammographic screening (p=0.523) did not. Differences in the stages of change after training were found to be statistically significant (p<0.001) and the group showed a progression in the stages of change in general (46.3%). In women mean scores of breast cancer awareness (p<0.000), severity (p<0.000), health motivation (p<0.000) and perception of the benefits of mammography (p<0.000) increased significantly and mean score of perception of mammography barriers decreased significantly (p<0.000) after the training. Conclusions: After the training on breast cancer and mammography it was determined that nursing interventions provided positive progression of stages of change of women, affected health beliefs positively and significantly increased BSE incidences. However, it did not have a significant effect on CBE and mammographic screening.

How Do People Experience Changes and Growths of the Self in On-line Game World? (온라인 게임 세계 속에서 게임 사용자들은 시간이 흐름에 따라 자신의 모습에서 어떠한 변화와 성장을 경험하는가?)

  • Do, Young-Yim;Whang, Sang-Min
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.1208-1217
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    • 2009
  • This research was conducted in an attempt to understand changes and growths of the self in on-line game world. Q methodology was used to investigate players in Mabinogi, which is an on-line game(MMORPG). Based on 57 behavior statements, Players distributed their changing experiences from when they were novices in on-line game world to the current state. In early start phase, they recognized that on-line game world was different from the reality. And they perceived their experiences in on-line game as separated from the real ones. However, as they spend more time in on-line game world, they began to realized that on-line game world is as real as the world because they function as an individual living in a society in both the game and the real world. They felt and learned that in on-line game life, they also need to follow the rules and order. In addition, trust and politeness were essential in order to live with other players. As time passed, the players realized that on-line game experiences have the same meanings and values as the real life ones. 3 types of self-changing patterns were found : Achievement change, Control change, and Relation change. The behavior patterns of the 3 types were then compared to Identify similarities and differences amongst them in psychological meanings and values in the on-line game life. This result illustrates that on-line game world can be defined as new behavioral setting or developmental context established by digital technology. In this new setting, people can experiment and understand their behavior patterns and also experience changes and growths of the self.

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Introduction to Tasks in the International Cooperation Project, DECOVALEX-2023 for the Simulation of Coupled Thermohydro-mechanical-chemical Behavior in a Deep Geological Disposal of High-level Radioactive Waste (고준위방사성폐기물 처분장 내 열-수리-역학-화학적 복합거동 해석을 위한 국제공동연구 DECOVALEX-2023에서 수행 중인 연구 과제 소개)

  • Kim, Taehyun;Lee, Changsoo;Kim, Jung-Woo;Kang, Sinhang;Kwon, Saeha;Kim, Kwang-Il;Park, Jung-Wook;Park, Chan-Hee;Kim, Jin-Seop
    • Tunnel and Underground Space
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    • v.31 no.3
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    • pp.167-183
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    • 2021
  • It is essential to understand the complex thermo-hydro-mechanical-chemical (THMC) coupled behavior in the engineered barrier system and natural barrier system to secure the high-level radioactive waste repository's long-term safety. The heat from the high-level radioactive waste induces thermal pressurization and vaporization of groundwater in the repository system. Groundwater inflow affects the saturation variation in the engineered barrier system, and the saturation change influences the heat transfer and multi-phase flow characteristics in the buffer. Due to the complexity of the coupled behavior, a numerical simulation is a valuable tool to predict and evaluate the THMC interaction effect on the disposal system and safety assessment. To enhance the knowledge of THMC coupled interaction and validate modeling techniques in geological systems. DECOVALEX, an international cooperation project, was initiated in 1992, and KAERI has participated in the projects since 2008 in Korea. In this study, we introduced the main contents of all tasks in the DECOVALEX-2023, the current DECOVALEX phase, to the rock mechanics and geotechnical researchers in Korea.

Organizational Buying Behavior in an Interdependent World (상호의존세계중적조직구매행위(相互依存世界中的组织购买行为))

  • Wind, Yoram;Thomas, Robert J.
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.2
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    • pp.110-122
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    • 2010
  • The emergence of the field of organizational buying behavior in the mid-1960’s with the publication of Industrial Buying and Creative Marketing (1967) set the stage for a new paradigm of thinking about how business was conducted in markets other than those serving ultimate consumers. Whether it is "industrial marketing" or "business-to-business marketing" (B-to-B), organizational buying behavior remains the core differentiating characteristic of this domain of marketing. This paper explores the impact of several dynamic factors that have influenced how organizations relate to one another in a rapidly increasing interdependence, which in turn can impact organizational buying behavior. The paper also raises the question of whether or not the major conceptual models of organizational buying behavior in an interdependent world are still relevant to guide research and managerial thinking, in this dynamic business environment. The paper is structured to explore three questions related to organizational interdependencies: 1. What are the factors and trends driving the emergence of organizational interdependencies? 2. Will the major conceptual models of organizational buying behavior that have developed over the past half century be applicable in a world of interdependent organizations? 3. What are the implications of organizational interdependencies on the research and practice of organizational buying behavior? Consideration of the factors and trends driving organizational interdependencies revealed five critical drivers in the relationships among organizations that can impact their purchasing behavior: Accelerating Globalization, Flattening Networks of Organizations, Disrupting Value Chains, Intensifying Government Involvement, and Continuously Fragmenting Customer Needs. These five interlinked drivers of interdependency and their underlying technological advances can alter the relationships within and among organizations that buy products and services to remain competitive in their markets. Viewed in the context of a customer driven marketing strategy, these forces affect three levels of strategy development: (1) evolving customer needs, (2) the resulting product/service/solution offerings to meet these needs, and (3) the organization competencies and processes required to develop and implement the offerings to meet needs. The five drivers of interdependency among organizations do not necessarily operate independently in their impact on how organizations buy. They can interact with each other and become even more potent in their impact on organizational buying behavior. For example, accelerating globalization may influence the emergence of additional networks that further disrupt traditional value chain relationships, thereby changing how organizations purchase products and services. Increased government involvement in business operations in one country may increase costs of doing business and therefore drive firms to seek low cost sources in emerging markets in other countries. This can reduce employment opportunitiesn one country and increase them in another, further accelerating the pace of globalization. The second major question in the paper is what impact these drivers of interdependencies have had on the core conceptual models of organizational buying behavior. Consider the three enduring conceptual models developed in the Industrial Buying and Creative Marketing and Organizational Buying Behavior books: the organizational buying process, the buying center, and the buying situation. A review of these core models of organizational buying behavior, as originally conceptualized, shows they are still valid and not likely to change with the increasingly intense drivers of interdependency among organizations. What will change however is the way in which buyers and sellers interact under conditions of interdependency. For example, increased interdependencies can lead to increased opportunities for collaboration as well as conflict between buying and selling organizations, thereby changing aspects of the buying process. In addition, the importance of communication processes between and among organizations will increase as the role of trust becomes an important criterion for a successful buying relationship. The third question in the paper explored consequences and implications of these interdependencies on organizational buying behavior for practice and research. The following are considered in the paper: the need to increase understanding of network influences on organizational buying behavior, the need to increase understanding of the role of trust and value among organizational participants, the need to improve understanding of how to manage organizational buying in networked environments, the need to increase understanding of customer needs in the value network, and the need to increase understanding of the impact of emerging new business models on organizational buying behavior. In many ways, these needs deriving from increased organizational interdependencies are an extension of the conceptual tradition in organizational buying behavior. In 1977, Nicosia and Wind suggested a focus on inter-organizational over intra-organizational perspectives, a trend that has received considerable momentum since the 1990's. Likewise for managers to survive in an increasingly interdependent world, they will need to better understand the complexities of how organizations relate to one another. The transition from an inter-organizational to an interdependent perspective has begun, and must continue so as to develop an improved understanding of these important relationships. A shift to such an interdependent network perspective may require many academicians and practitioners to fundamentally challenge and change the mental models underlying their business and organizational buying behavior models. The focus can no longer be only on the dyadic relations of the buying organization and the selling organization but should involve all the related members of the network, including the network of customers, developers, and other suppliers and intermediaries. Consider for example the numerous partner networks initiated by SAP which involves over 9000 companies and over a million participants. This evolving, complex, and uncertain reality of interdependencies and dynamic networks requires reconsideration of how purchase decisions are made; as a result they should be the focus of the next phase of research and theory building among academics and the focus of practical models and experiments undertaken by practitioners. The hope is that such research will take place, not in the isolation of the ivory tower, nor in the confines of the business world, but rather, by increased collaboration of academics and practitioners. In conclusion, the consideration of increased interdependence among organizations revealed the continued relevance of the fundamental models of organizational buying behavior. However to increase the value of these models in an interdependent world, academics and practitioners should improve their understanding of (1) network influences, (2) how to better manage these influences, (3) the role of trust and value among organizational participants, (4) the evolution of customer needs in the value network, and (5) the impact of emerging new business models on organizational buying behavior. To accomplish this, greater collaboration between industry and academia is needed to advance our understanding of organizational buying behavior in an interdependent world.

A Study on the Preparation and Growth Mechanism of Titanium Dioxide using Organic-Inorganic Hybrid Titanium Complex (유무기 하이브리드 티타늄 착화합물을 이용한 티타니아의 제조 방법 및 성장 거동에 대한 연구)

  • Kang, Yubin;Choi, Jin-Ju;Kwon, Nam Hun;Kim, Dae-Guen;Lee, Kun-Jae
    • Journal of Powder Materials
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    • v.26 no.6
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    • pp.487-492
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    • 2019
  • Titanium dioxide (TiO2) is a typical inorganic material that has an excellent photocatalytic property and a high refractive index. It is used in water/air purifiers, solar cells, white pigments, refractory materials, semiconductors, etc.; its demand is continuously increasing. In this study, anatase and rutile phase titanium dioxide is prepared using hydroxyl and carboxyl; the titanium complex and its mechanism are investigated. As a result of analyzing the phase transition characteristics by a heat treatment temperature using a titanium complex having a hydroxyl group and a carboxyl group, it is confirmed that the material properties were different from each other and that the anatase and rutile phase contents can be controlled. The titanium complexes prepared in this study show different characteristics from the titania-formation temperatures of the known anatase and rutile phases. It is inferred that this is due to the change of electrostatic adsorption behavior due to the complexing function of the oxygen sharing point, which crystals of the TiO6 structure share.

Change in Corrosion Resistance of Solution-Treated AZ91-X%Sn Magnesium Alloys (용체화처리한 AZ91-X%Sn 마그네슘 합금의 부식 저항성 변화)

  • Moon, Jung-Hyun;Jun, Joong-Hwan
    • Journal of the Korean Society for Heat Treatment
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    • v.28 no.5
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    • pp.229-238
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    • 2015
  • The effects of Sn addition and solution treatment on corrosion behavior were studied in AZ91 magnesium casting alloy. The addition of 5%Sn contributed to the introduction of $Mg_2Sn$ phase, to the reduction in dendritic cell size and to the increase in the amount of secondary phases. After the solution treatment, trace amount of $Al_8Mn_5$ particles were observed in the ${\alpha}$-(Mg) matrix for the AZ91 alloy, while $Mg_2Sn$ phase with high thermal stability was additionally found in the AZ91-5%Sn alloy. Before the solution treatment, the AZ91-5%Sn alloy had better corrosion resistance than the Sn-free alloy, which is caused by the enhanced barrier effect of the (${\beta}+Mg_2Sn$) phases formed more continuously along the dendritic cell boundaries. It is interesting to note that after the solution treatment, the corrosion rate of both alloys became increased, but the Sn-added alloy showed higher corrosion rate than the Sn-free alloy. The microstructural examination on the corroded surfaces revealed that the remaining $Mg_2Sn$ particles in the solution-treated AZ91-5%Sn alloy play a role in accelerating corrosion by galvanic coupling with the ${\alpha}$-(Mg) matrix.