• Title/Summary/Keyword: 지향성

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Characteristics and Kinetics of the Addition Reaction of Resol Resin Formation (레졸수지 합성에서 부가반응 특성 및 반응속도론)

  • Ann, Jae-Ok;Nam, Young-Woo
    • Korean Chemical Engineering Research
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    • v.46 no.2
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    • pp.301-309
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    • 2008
  • In this study, the effect of formaldehyde to phenol (F/P) molar ratios, catalyst wt%, and reaction temperature on the chemical structure was studied utilizing a two-level full factorial experimental design. The effect of three variables on the chemical structure was analyzed by using three-way ANOVA of SPSS. Concentration of methyrol-substituted phenols after 300 min addition reaction increased with higher the F/P mole ratio, lower the reaction temperature and lower the catalyst wt%. Resol catalysed by barium hydroxide showed higher addition of formaldehyde onto ortho positions of phenolic rings. A simplified elementary reaction model for resole type phenolic resin formation which do not consider the dissociation of phenolic compounds and the fraction of formaldehyde in the form of methylene glycol was proposed and compared with Zavitsas' type models. Elementary reaction model showed error of 2.79% compared to the error of 3.27% in Zavitsas' type models. It was thought that the elementary reaction model could be used to predict the behavior of addition reaction in resol formation.

A Study on the Improvement of the Directivity for Rectangular Microstrip Patch Array Antennas Conformed to a Cylindrical Surface (원통면에 정합-배열된 장방형 마이크로스트립 패치 안테나의 지향성 개선을 위한 연구)

  • 고광태;구연건
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.5 no.2
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    • pp.46-54
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    • 1994
  • In this paper, an analysis and design method is proposed, which is to improve the directivity of microstrip array antennas conformed to a cylindrical surface. In the case of forming an arc-array in the circumferential direction on a circula-cylinder surface, the circular-cylinder can be approximated to a polygonal-pillar and on each pillar-planes the sub-arrays, Dolph-Tschebyscheff array and uniform array with a beam steered in the desired direction, would make a sharp directivity for the total cylin- drical array antenna. And the radiation pattern according to the type of its sub arrays is analyzed and compared using the cylindrical-cavity codel. A cylindrical microstrip array antenna, with 12 elements and uniform arra as a sub-array which have an equal distance$\lambda_0$/2between the elements, is manufactured and conformed to a cylinder with radius of 6 The measured data of side lobe level, HPBW and FNBW are - 13dB, $9^{\circ}$, and $15{\circ}$, ,respectively. This result shows a good improvement on the directivity comparing with a linear array.

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Analysis of Relationship between Functional Areas and Individual Competencies of Extension Workers (농촌지도사의 직무영역과 개별역량의 관계분석)

  • Kim, Hyo Mi;Kim, Ji Hyun;Kim, Sa Gyun;Kim, Yoon Doo
    • Journal of Agricultural Extension & Community Development
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    • v.20 no.2
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    • pp.383-405
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    • 2013
  • The purpose of this study is trying to drive the competence relevant to extension worker's functions. We also conducted a correspondence analysis between the individual competence and extension worker's functions. As a result of the analysis, the functions of guidance planning correlated with 'problem solving' and 'creation of ideas'. Education functions correlated with 'extension work evaluation', 'customer satisfaction' and 'understanding'. And crop technology diffusion functions were analyzed relevant to the ability of 'training skill' and 'responsibility' is high. In this study, extension empowerment need to educate suitable education which is high relation between competency and extension worker's functions and develop new suitable education model. And the baseline data will be made use, when arrange reasonable function to new extension workers, through individual competency measured.

Governance Thoery as Ways of Applying a Policy for incorporating Media into Education in Digital Environment (디지털 환경에서의 미디어교육에 대한 거버넌스 이론의 활용에 대한 연구)

  • Shim, Young-Sub;Kim, Dong-Gyu
    • Korean journal of communication and information
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    • v.58
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    • pp.242-261
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    • 2012
  • This study was intended to analyze media in education policy from the governance perspective and suggested some orientations and innovative ideas to a new governance in media in Education. For these purposes, this study reviewed related literature about media in education and governance policy and drew a governance model of educational community as an analytic scheme to understand a governance approach to orientation-order-performance of Schmank. Thereafter, the study analyzed formulation and implementation processes of media in education policy, based on some criteria to operate the model, and also analyzed the policy governance in a comprehensive way. Based on the results, this study suggested recommendations to innovate current media in education governance as follows: (1) working towards an idea of operative cooperation through reforms (2) constructing a rational policy system to incorporate socio-political variables, and (3) activating cooperative governance to transform 'governing' into 'governance'.

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Factor Analysis & SDLRS Assessment in Science and Engineering Fields' Students; In Case of KUT's Students (이공계 대학생의 자기주도학습준비도 진단 및 요인분석 - 한국기술교육대학교 재학생을 중심으로)

  • Lim, Se-Young;Lee, Woong-Il
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.2 no.1
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    • pp.17-27
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    • 2010
  • In this study, the assessment and the factor analysis of the self-directed learning readiness for engineering students were conducted. As measurement tool was used the self-directed learning readiness scale of Guglielmino's SDLRS questionnaire in Korean translation. It was surveyed under 519 students of Faculty of Engineering of Korea University of Technology and Education. Responded questionnaires were 496. As a result, seven factors were identified: (1)openness to learning, (2)initiative and inquiring mind, (3)independence and basic learning skills, (4)creativity, (5)accepting responsibility for learning, (6)love of learning, (7)positive orientation of the future. And the scale was confirmed in validity. It was confirmed that the mean value of openness to learning and of love of learning were higher than average, while mean value of independence and basic learning skills, accepting responsibility for learning were lower than average, there was the difference in SDLRS by students' personal backgrounds, but there were statistically significant differences in seven factors.

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A Study of UHF RFID Metallic Tag Design for Long Reading Range Using a Cavity Structure (캐비티 구조를 사용한 장거리 인식용 UHF RFID 금속용 태그 설계에 관한 연구)

  • Lee, Jin-Seong;Lee, Kyoung-Hwan;Yeo, Jun-Ho;Chung, You-Chung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12B
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    • pp.1468-1474
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    • 2009
  • This paper shows an UHF RFID metallic tags using a Cavity structure for a long reading range. The reading range of a general passive tag is limited because the EIRP of a reader system is limited as 36㏈m by ISO 18000-6. To extend the reading range, the tag antenna should have a high gain antenna structure. The designed tag antenna is recognized over 10m range with a Cavity structure. The directivity pattern and the performance of the tag with the Cavity structure is stable when it is attached to a metallic object. The designed tag antenna has two kinds as cavity thickness. The sizes of designed tag antennas are $176\;{\times}\;52\;{\times}\;10\;mm$ and $176\;{\times}\;61\;{\times}\;30mm$ They can be attached to a large metallic materials and heavy equipments. The measured reading ranges of the tags are about 11m and 15m when they are attached to a metallic object.

IMS지향성과 기업문화 적합도가 IMS활동의 이행수준과 성과에 미치는 영향

  • Kim, Gyeong-Il
    • Proceedings of the Korea Database Society Conference
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    • 2010.06a
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    • pp.5-12
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    • 2010
  • With a sample of 147 Korean small and medium size companies, this study examined the relationships among degree of information orientation, corporate culture, degree of information management implementation and selected business performances in the process of implementing IMS improvement programs, such as IMS(Information Management System). Information orientation is defined as company-wide understanding and implementation of the underlying philosophy, principles, approached, and tools of information improvement programs. It is assumed that successful implementation of information improvement programs requires a information-oriented mind-set of the employees. The key elements of information orientation include continious improvement structured processes, organixation-wide participation and customer-focused spirit. Culture id defined as the value and beliefs of em organization that shape its behavior. It is also assumed that successful implementation of information improvement programs require strong support from s corporate culture that emphasizes cintinious improvement. Adopting the competing values model of Quinn and McGrath(1985), corporate culture is classified into 'flexible' versus 'controlled culture' and 'outer-directed' versus 'inner-directed culture'. Fitness was defined through the relationship between levels of information oriented and types of corporate culture. The results were as follows. First, it was found that when a company with high information orientation promoted information innovation programs, such as IMS, it reported higher degree of information management implementation and improvement in business performances. Second, the results showed the importance of 'flexible culture' and 'outer-directed culture' in performing information, innovation. Regarding the types of corporate culture, the analysis found that developmental culture, rational culture and group culture were effective. Third, companies with high information oriented and flexible culture or companies with high information orientation and outer-directed culture reported the highest implementation in Information management activities. Fourth, the results showed that the level of information management implementation had a mediating effect on the relationship between information orientation and business performance. It was also found that enhanced non-financial performance led to the improvement of financial performance. This study attempted to exaime the factor that lead information management program to success. In order to reach success, first, it is suggested that companies have positive mind set toward continious information improvement. Secondly, it is recommended that a flexible and outer-directed culture appropriate for continious information improvement is cultivated.

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Parametric Array Sonar System Based on Maximum Likelihood Detection (최대우도 검파에 기반한 파라메트릭 어레이 소나 시스템)

  • Han, Jeong-Hee;Lee, Chong-Hyun;Paeng, Dong-Guk;Bae, Jin-Ho;Kim, Won-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.1
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    • pp.25-31
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    • 2011
  • In the underwater communications, transmitted acoustic signal is corrupted by interference from multipath. A parametric array transducer is capable of radiating a narrow beam with very low sidelobe levels. In certain cases, the parametric array transducer can help the multipath problem. To improve the performance of the underwater communications, the statistical signal processing methods will be required. In the paper, the communication system using a parametric array transducer was demonstrated. To detect the received signal of the communication system based on the on-off keying, the maximum likelihood method using averaged signal for a particular window size is used. The communication system has GUI using LebVIEW which allows the user to change the parameter. The GUI can also be easily modified based on the characteristics of a parametric array transducer. The implemented system can effectively evaluate the performance of the parametric array transducer.

UHF Cavity-backed Spiral Antenna for Partial Discharge Diagnosis (부분방전 진단용 UHF cavity-backed 스파이럴 안테나)

  • Kim, Han Byul;Kim, Jin Hyuk;Hwang, Keum Cheol;Shin, Jae Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.12
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    • pp.89-94
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    • 2012
  • In this paper, a UHF cavity-backed spiral antenna for partial discharge diagnosis is proposed. The proposed antenna consists of two-arm Archimedean spiral, a cavity, and a balun for feeding. The spiral antenna is designed for 0.3-1.5 GHz operating frequency. Two spiral arms of the proposed antenna are fed by a microstrip tapered-balun. In order to enhance the gain, the cavity is located in the back side of the spiral pattern. The proposed antenna is designed and simulated using CST Microwave Studio. The designed antenna is also fabricated and tested to validate performance. The measured radiation patterns are directional to the +z-axis and measured peak gain is 9.92 dBi.

A Study on Research & Development and Quality Stability of Functional Red Pepper Dressing (기능성 고추드레싱의 개발 및 품질 안정성에 관한 연구)

  • 손무호
    • Culinary science and hospitality research
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    • v.10 no.2
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    • pp.107-120
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    • 2004
  • In recently, foods must to be contained a health point and fashionable feeling, mayonnaise was called pronoun of dressing must be changes to new products. At this point, new type's dressing oil was research and developing used for raw- materials of 13 kinds. Red pepper seasoning oil, seasoning soy sauce, seasoning solution and seasoning oil were manufactured from soy sauce, vinegar, garlic etc. Manufacturing of new type's dressing oil(DO) could from only blending of these seasoning raw-materials. The result of organoleptic test about vegetables, pizzas and meats was esquired a distinction. According to, it was treated to addition of a functional raw-materials. In this study, it was investigated red pepper DO and DO for diabetic, adult disease patient as well as DO for children, Japanese dining room, general man etc. But these DO products had trouble to layer separation of upper layer and bottom layer, this problem was happened to shaking. This troubles were able to treat gums and emulsifiers.

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