• Title/Summary/Keyword: Environment data

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A Study for Design and Performance Improvement of the High-Sensitivity Receiver Architecture based on Global Navigation Satellite System (GNSS 기반의 고감도 수신기 아키텍처 설계 및 성능 향상에 관한 연구)

  • Park, Chi-Ho;Oh, Young-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.4
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    • pp.9-21
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    • 2008
  • In this paper, we propose a GNSS-based RF receiver, A high precision localization architecture, and a high sensitivity localization architecture in order to solve the satellite navigation system's problem mentioned above. The GNSS-based RF receiver model should have the structure to simultaneously receive both the conventional GPS and navigation information data of future-usable Galileo. As a result, it is constructed as the multi-band which can receive at the same time Ll band (1575.42MHz) of GPS and El band (1575.42MHz), E5A band (1207.1MHz), and E4B band (1176.45MHz) of Galileo This high precision localization architecture proposes a delay lock loop with the structure of Early_early code, Early_late code, Prompt code, Late_early code, and Late_late code other than Early code, Prompt code, and Late code which a previous delay lock loop structure has. As we suggest the delay lock loop structure of 1/4chips spacing, we successfully deal with the synchronization problem with the C/A code derived from inaccuracy of the signal received from the satellite navigation system. The synchronization problem with the C/A code causes an acquisition delay time problem of the vehicle navigation system and leads to performance reduction of the receiver. In addition, as this high sensitivity localization architecture is designed as an asymmetry structure using 20 correlators, maximizes reception amplification factor, and minimizes noise, it improves a reception rate. Satellite navigation system repeatedly transmits the same C/A code 20 times. Consequently, we propose a structure which can use all of the same C/A code. Since this has an adaptive structure and can limit(offer) the number of the correlator according to the nearby environment, it can reduce unnecessary delay time of the system. With the use of this structure, we can lower the acquisition delay time and guarantee the continuity of tracking.

A Study on the Characteristics of Tropical Cyclone Passage Frequency over the Western North Pacific using Empirical Orthogonal Function (경험적 직교함수를 이용한 북서태평양 열대저기압의 이동빈도 특성에 관한 연구)

  • Choi, Ki-Seon;Kang, Ki-Ryong;Kim, Do-Woo;Hwang, Ho-Seong;Lee, Sang-Ryong
    • Journal of the Korean earth science society
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    • v.30 no.6
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    • pp.721-733
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    • 2009
  • A pattern of tropical cyclone (TC) movement in the western North Pacific area was studied using the empirical orthogonal function (EOF) and the best track data from 1951 to 2007. The independent variable used in this study was defined as the frequency of tropical cyclone passage in 5 by 5 degree grid. The $1^{st}$, $2^{nd}$ and $3^{rd}$ modes were the east-west, north-south and diagonal variation patterns. Based on the time series of each component, the signs of first and second mode changed in 1997 and 1991, respectively, which seems to be related to the fact that the passage frequency was higher in the South China Sea for 20 years before 1990s, and recent 20 years in the East Asian area. When the eigen vectors were negative values in the first and second modes and TC moves into the western North Pacific, TC was formed mainly at the east side relatively compared to the case of the positive eigen vectors. The first mode seems to relate to the pressure pattern at the south of Lake Baikal, the second mode the variation pattern around $30^{\circ}N$, and the third mode the pressure pattern around Japan. The first mode was also closely related to the ENSO and negatively related to the $Ni\tilde{n}o$-3.4 index in the correlation analysis with SST anomalies.

The Organization Commitment and Perception of Human Resource Management by Employment Types of School Foodservice Employees (학교급식 직원의 고용유형에 따른 인적 자원 관리 활동에 대한 인식과 조직 몰입도)

  • Lee, Ok;Cho, Minju;Chang, Hyeja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.1
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    • pp.162-171
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    • 2014
  • As the foodservice industry is labor intensive, the efficient management of human resources is an essential element for improving operational efficiency. This study was designed to investigate the performance level of human resource management in self-operated school foodservices and to examine the relationship between human resource management, organizational commitment, and productivity. Whether these factors rated differently by employment and job types was also examined. Data were collected through questionnaires distributed to 60 dieticians and 240 cooks in Seongnam and Yongin. Frequency analysis, factor analysis, the t-test and multiple regression analysis were tested using Minitab. Human resource management practices rated highly in the dimension of employee training (3.51), followed by working environment (3.39), and turnover management (3.37). In contrast, reward management (1.73) and working condition (1.56) received the lowest score. Organizational commitment scored 3.65 points, and showed that dedication (3.82) was the highest score; however, self-esteem (3.50) was the lowest score. For human resource management, there were significant differences between employment types as full time workers (3.85) rated management more highly than part-time worker (3.43). Overall productivity was fairly high, especially in high school foodservices. Only the performance appraisal had an influence on organizational commitment (${\beta}$=0.292, P<0.05). Productivity was positively correlated with human resource management (r=0.432, P<0.001) and organizational commitment (r=0.36, P<0.01). In conclusion, school foodservices need to establish objective performance standards, and increase employee morale by enhancing reward systems and working conditions. In particular, irregular employees require training with job performance standards and given a proper reward program, depending on their performance, to improve organizational commitment.

The Analysis of Vegetation-Environment Relationship of the Taxus cuspidata Forests by TWINSPAN and DCCA (TWINSPAN 및 DCCA에 의한 한반도(韓半島) 주목림(林)의 군락(群落)과 환경(環境)의 상관관계(相關關係) 분석(分析))

  • Shin, Hyun Chul;Lee, Kang Young;Song, Ho Kyung
    • Journal of Korean Society of Forest Science
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    • v.87 no.4
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    • pp.535-542
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    • 1998
  • This study was carried out for the purpose of supplying the basic data for artificial forestation, natural regeneration and ecological conservation etc., and obtaining information on alpine vegetation, by establishing vegetation units on the basis of phytosociological classification of community and studying growth pattern on the basis of species composition, hierarchy structure and population dynamics, for Taxes cuspidata naturally growing at the alpine districts in Korea. The importance value of Taxus cuspidata by districts mostly showed above 100 in the upper story but at Mt. Chiri and Mt. Hanra communities its value was comparatively low. In the middle story it showed lower value than that of upper story and not quite showed at Mt. Chiri. Taxus cuspidata communities in the lower story were only in Mt. Hanra, Mt. Odae and Mt. Sobaek, and their importance values were about 10 which were relatively low values. The communities were classified into five groups as Taxus cuspidata-Males baccata var. mandshurica, Taxus cuspidata-Abies nephrolepis, Taxus cuspidata-Abies koreana, Taxus cuspidata-Acer mono and Taxus cuspidata-Euonymus quelpaertensis by TWINSPAN analysis. Taxus cuspidata-Abies koreana community was distributed at the northern aspect of the mountain ridges and at higher elevation than other communities and distributed. Taxus cuspidata-Acer mono community was relatively low than the others and distributed at the hillsides of mountain. And Taxus cuspidata-Euonymus quelpaertensis communities were distributed at the relatively high elevation and northern and eastern aspect of the mountain tap, and Taxus cuspidata-Malus baccata var. mandshurica communities were distributed at the medium elevation, and southern and eastern aspect of the mountain ridge. In the relation between communities and environmental factors, it was correlated with aspect, elevation and topography at the first axis, and elevation, slope at the second axis.

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Preference, Perception, Need to Study, Practice of Learned Content and Learning Needs with Respect to the Clothing and Textiles Section of the Technology and Home Economics Curriculum (기술.가정 교과내의 의생활영역에 대한 선호도, 인식, 필요도, 실천도, 학습요구도)

  • Son Jin-Sook;Shin Hye-Won
    • Journal of Korean Home Economics Education Association
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    • v.18 no.3 s.41
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    • pp.149-161
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    • 2006
  • This study examined preferences for the clothing and textiles section of 'Technology and Home Economics' course, comparing males to females, and subdividing three groups based on the preference of the clothing and textiles section: a high-preference group, a medium-preference group, and a low-preference group. Their perceptions of the section. need to study, level of practice of teamed content, and learning needs were compared between males and females and among the three sub-groups. The subjects of this study were 176 male and 176 female high school students in Seoul. Data were collected using questionnaires with a 5-plint scale in September, 2004. Finally, 352 questionnaires were analyzed by the SPSS program. The results showed that all preferences for the clothing and textiles section were average and girls' preferences were higher than boys' preferences. General perceptions of the clothing and textiles section were positive, and there were no significant differences by gender. The perceptions of the high-preference group were more positive than those of the other two groups. The perceived importance of studying was high. especially with respect to clothing care and storage. Girls reported a greater need to study than boys did. Among both boys and girls, the high-preference group reported a greater need to study than the middle and low-preference groups did. The level of practice of learned content was leo, except for contents related to attire and the purchase of clothing. Girls practiced contents learned about attire more than boys did. Among boys, the high-preference group practiced contents teamed in all areas more than boys in the other two groups. However, among girls. only content related to attire was preferentially practiced by the high-preference group. Both boys and girls exhibited tile greatest learning need for fashion coordination. Girls had more learning needs than boys in all contents, except for clothing and environment. Among all students, the higher the level of preference, the higher their learning needs.

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Middle School Home Economics Teachers Perspective about Home Economics Curriculum and Housing Education Value (중학교 가정과 교사의 교육과정 관점과 주거교육 가치관)

  • Lee, Yeon-Jung;Cho, Jae-Soon;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.19 no.4
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    • pp.219-232
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    • 2007
  • The purpose of this study was to investigate middle school Home Economics(HE) teachers' perspective on HE curriculum, their Housing Education Value in Home Economics, and then find out correlations between them. Questionnaire was administered to HE teachers who had experienced teaching Housing content over the whole country through e-mail or face-to-face meeting. 207 data collected from the responses were finally analyzed statistically with mean, standard deviation, percentage, T-test, one-way ANOVA, post verification(Scheffe) and Pearson correlation by using SPSS/WIN(ver. 10.0) program. The results of the study were as follows: First, about Home Economics teachers' perspective on HE curriculum, the existential perspective was the highest, followed by the structural perspective and the traditional perspective. Second, about their perspectives on Housing Education Value, generally the most important thing they value was an aspect of ecology, followed by an aspect of economics, an aspect of Socio-Psychology, an aspect of space planning, an aspect of local environment, an aspect of career education, an aspect of culture, an aspect of housing management and an aspect of housing policy. Third, about the relation between their perspectives on curriculum and Housing Education Value, among 9 kinds of Housing Education Value, the traditional perspective was low associated with only housing management value including to Housing Education Value. However, the existential perspective and the structural perspective tended to be moderately or low associated with most of the values including to Housing Education Value.

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Needs analysis for development of training program for newly appointed Home Economics teachers - Focusing on the participants of first-grade teachers qualification training - (초임기 가정과 교사 직무연수 프로그램 개발에 대한 요구 분석 - 1급 정교사 가정 자격연수 대상자 중심으로 -)

  • Lee, Hyunjung
    • Journal of Korean Home Economics Education Association
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    • v.30 no.1
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    • pp.15-28
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    • 2018
  • Teachers are not completed by appointment, but gradually made through self-development and training for a long time. In order to improve a sense of responsibility of home economics teachers, and also to suggest the purpose and direction of program through job training, the needs of training subjects should be preferentially understood. Thus, this study aims to provide basic data for establishing the developmental operation measures of training for home economics teachers, by researching the needs for training performed after the qualification training for first-grade teachers, targeting the teachers participating in the qualification training program for first-grade teachers of home economics in 2017. About the half of the research subjects received the home economics training one time or less for last three years. Through the training for first-grade teachers, the technical improvement of lesson instruction was demanded the most. As professional qualifications that should be cultivated through training, the ability to develop teaching methods and teaching/learning materials was the highest. Regarding the theme of training, the development of teaching/learning materials for home economics was desired the most. They wanted the training method including direct participation with high utilization for lesson, sublation of competition-centered evaluation, preference of instructors with field experience, continuous opportunity of home economics training, and communicative training. Regarding the needs for the 2015 revised curriculum, the demand for the training of 'human development and family' area was the highest. Therefore, in order to improve the professionalism of teachers through home economics training, it would be necessary to improve the educational environment such as temporal room for training and administrative support, and also to provide diverse types of training like group training, remote training, and smartphone app training suitable for changes in the generation of teachers. Also, on top of forming communities of home economics teachers, and sharing great contents of training, there should be individually-customized training for practice and sharing lesson cases.

Development of Intelligent ATP System Using Genetic Algorithm (유전 알고리듬을 적용한 지능형 ATP 시스템 개발)

  • Kim, Tai-Young
    • Journal of Intelligence and Information Systems
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    • v.16 no.4
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    • pp.131-145
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    • 2010
  • The framework for making a coordinated decision for large-scale facilities has become an important issue in supply chain(SC) management research. The competitive business environment requires companies to continuously search for the ways to achieve high efficiency and lower operational costs. In the areas of production/distribution planning, many researchers and practitioners have developedand evaluated the deterministic models to coordinate important and interrelated logistic decisions such as capacity management, inventory allocation, and vehicle routing. They initially have investigated the various process of SC separately and later become more interested in such problems encompassing the whole SC system. The accurate quotation of ATP(Available-To-Promise) plays a very important role in enhancing customer satisfaction and fill rate maximization. The complexity for intelligent manufacturing system, which includes all the linkages among procurement, production, and distribution, makes the accurate quotation of ATP be a quite difficult job. In addition to, many researchers assumed ATP model with integer time. However, in industry practices, integer times are very rare and the model developed using integer times is therefore approximating the real system. Various alternative models for an ATP system with time lags have been developed and evaluated. In most cases, these models have assumed that the time lags are integer multiples of a unit time grid. However, integer time lags are very rare in practices, and therefore models developed using integer time lags only approximate real systems. The differences occurring by this approximation frequently result in significant accuracy degradations. To introduce the ATP model with time lags, we first introduce the dynamic production function. Hackman and Leachman's dynamic production function in initiated research directly related to the topic of this paper. They propose a modeling framework for a system with non-integer time lags and show how to apply the framework to a variety of systems including continues time series, manufacturing resource planning and critical path method. Their formulation requires no additional variables or constraints and is capable of representing real world systems more accurately. Previously, to cope with non-integer time lags, they usually model a concerned system either by rounding lags to the nearest integers or by subdividing the time grid to make the lags become integer multiples of the grid. But each approach has a critical weakness: the first approach underestimates, potentially leading to infeasibilities or overestimates lead times, potentially resulting in excessive work-inprocesses. The second approach drastically inflates the problem size. We consider an optimized ATP system with non-integer time lag in supply chain management. We focus on a worldwide headquarter, distribution centers, and manufacturing facilities are globally networked. We develop a mixed integer programming(MIP) model for ATP process, which has the definition of required data flow. The illustrative ATP module shows the proposed system is largely affected inSCM. The system we are concerned is composed of a multiple production facility with multiple products, multiple distribution centers and multiple customers. For the system, we consider an ATP scheduling and capacity allocationproblem. In this study, we proposed the model for the ATP system in SCM using the dynamic production function considering the non-integer time lags. The model is developed under the framework suitable for the non-integer lags and, therefore, is more accurate than the models we usually encounter. We developed intelligent ATP System for this model using genetic algorithm. We focus on a capacitated production planning and capacity allocation problem, develop a mixed integer programming model, and propose an efficient heuristic procedure using an evolutionary system to solve it efficiently. This method makes it possible for the population to reach the approximate solution easily. Moreover, we designed and utilized a representation scheme that allows the proposed models to represent real variables. The proposed regeneration procedures, which evaluate each infeasible chromosome, makes the solutions converge to the optimum quickly.

S-MADP : Service based Development Process for Mobile Applications of Medium-Large Scale Project (S-MADP : 중대형 프로젝트의 모바일 애플리케이션을 위한 서비스 기반 개발 프로세스)

  • Kang, Tae Deok;Kim, Kyung Baek;Cheng, Ki Ju
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.8
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    • pp.555-564
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    • 2013
  • Innovative evolution in mobile devices along with recent spread of Tablet PCs and Smart Phones makes a new change not only in individual life but also in enterprise applications. Especially, in the case of medium-large mobile applications for large enterprises which generally takes more than 3 months of development periods, importance and complexity increase significantly. Generally Agile-methodology is used for a development process for the medium-large scale mobile applications, but some issues arise such as high dependency on skilled developers and lack of detail development directives. In this paper, S-MADP (Smart Mobile Application Development Process) is proposed to mitigate these issues. S-MADP is a service oriented development process extending a object-oriented development process, for medium-large scale mobile applications. S-MADP provides detail development directives for each activities during the entire process for defining services as server-based or client-based and providing the way of reuse of services. Also, in order to support various user interfaces, S-MADP provides detail UI development directives. To evaluate the performance of S-MADP, three mobile application development projects were conducted and the results were analyzed. The projects are 'TBS(TB Mobile Service) 3.0' in TB company, mobile app-store in TS company, and mobile groupware in TG group. As a result of the projects, S-MADP accounts for more detailed design information about 'Minimizing the use of resources', 'Service-based designing' and 'User interface optimized for mobile devices' which are needed to be largely considered for mobile application development environment when we compare with existing Agile-methodology. Therefore, it improves the usability, maintainability, efficiency of developed mobile applications. Through field tests, it is observed that S-MADP outperforms about 25% than a Agile-methodology in the aspect of the required man-month for developing a medium-large mobile application.

Economic Effects of Eliminating Trade Barriers under Imperfect Competition (불완전경쟁하(不完全競爭下)에서의 무역장벽(貿易障壁) 완화효과(緩和效果))

  • Lee, Hong-gue
    • KDI Journal of Economic Policy
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    • v.14 no.2
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    • pp.29-54
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    • 1992
  • Recent studies on the economic effects of trade liberalization and economic integration have emphasized the significant gains associated with product differentiation and scale economies. Securing access to markets in other countries will make it possible to increase product variety and capture scale economies, thus, expanding the gains from trade. Liberalization is also expected to introduce foreign competition into the previously closed market. Concurrently, the liberalization will improve the competitive market environment for firms selling in the domestic market. Firms will be pressed to either exit or reduce cost. The output per firm, then, will increase due to the exit of rival firms, and the average total cost will decline due to the economies of scale. 'Rationalization' of the production process will eventually follow. This paper addresses the economic effects of (counterfactual) bilateral tariff elimination between Korea and Japan. It computationally assesses the gains from liberalization as well as the resource allocations and welfare effects associated with the tariff reduction. The endogenous determination of the key parameters distinguishes this paper from others. The firm's perceived elasticity of demand and elasticity of substitution in the present model are calibrated to be consistent with the base year data. Korea, Japan, and the rest of the world are modeled explicitly. The sectoral coverage of the model includes twenty-three tradable product categories based on three-digit SITC industries and seven nontradable categories based on one-digit SITC industries. Product categories are also classified into perfectly competitive and imperfectly competitive ones. In the imperfectly competitive industries, product differentiation exists at the firm level, while the perfectly competitive industries are characterized by national product differentiation. The simulation results of bilateral tariff reduction are reported. Tariff elimination tends to increase intra-industry trade flows so that the total amount of exports and imports of both countries expand. Yet, Japan is expected to increase the bilateral trade surplus in the wake of the mutual tariff reduction. Terms-of-trade for Korea will not change, while for Japan it will deteriorate. Equivalent variations reflecting the change in consumer surplus (welfare) will favor Korean consumers. Total output, however, will not change substantially, recording 0.5 and 0.6% for Japan and Korea, respectively. An interesting finding in the analysis is that the gains from increased competition and scale efficiency are not as prevailing as expected in theory.

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