• Title/Summary/Keyword: research and development

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Analysis of Utilization and Maintenance of Major Agricultural machinery (Tractor, Combine Harvester and Rice Transplanter) (핵심 농기계(트랙터, 콤바인 및 이앙기) 이용 및 수리실태 분석)

  • Hong, Sungha;Choi, Kyu-hong
    • Journal of the Korean Society of International Agriculture
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    • v.30 no.4
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    • pp.292-299
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    • 2018
  • In a survey in which farmers were asked about their levels of satisfaction with agricultural machines, Japanese products scored higher than local products by 1.2, 1.3, and 1.4 times for tractors, combine harvesters, and rice transplanter, respectively. Japanese products corresponded to generally high satisfaction levels in terms of operating performance, operability, frequency of breakdowns, and durability, excluding sales price and after-sales services. Effective countermeasures through quality improvement are therefore necessary for Korean products. Furthermore, a survey of dealers showed that the components and consumables for core agricultural machines had high frequencies of breakdowns and repairs. Four major components of tractors represented 85.3% of all breakdowns and repairs, five components of combine harvesters represented 89.6%, and three components of rice transplanters represented 80.5%. Moreover, a comparison of the technological levels between local and imported machines showed that the local machines' levels were at 60-100% for tractors, 70-100% for combine harvesters, and 70-95% for rice transplanters. Small and mid-sized tractors, 4 interrow combine harvesters, and 6 interrow rice transplanters showed similar levels of technology. The results of the analysis suggest that action is urgently needed at a policy level to establish an agricultural machinery component research center for the development, production, and supply of commonly-used components, with the participation of manufacturers of agricultural machines and components, in order to enhance the competitiveness of local manufacturers and to revitalize the agricultural machine market.

A Development and Validation Study of the Web-based Korean Version of the Eating Disorder Diagnostic Scale DSM-5 (웹 기반 한국판 섭식장애진단척도 DSM-5의 개발 및 타당화 연구)

  • Lee, Hye Rin;Kwag, Kyung Hwa;Lee, You Kyung;Han, Soo Wan;Kim, Youl-Ri
    • Korean Journal of Psychosomatic Medicine
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    • v.28 no.2
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    • pp.185-193
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    • 2020
  • Objectives : The aim of this study was to develop and to verify the Korean version of the Eating Disorder Diagnosis Scale DSM-5 (K-EDDS) as a web-based diagnostic system, which enables rapid diagnosis of patients for early intervention. Methods : A total of 119 persons participated in the study, including patients with eating disorders (n=38) and college students (n=81). Along with the paper-and-pencil SCOFF, all participants completed the web-based K-EDDS, the Eating Disorder Examination-Questionaire (EDE-Q), and the Clinical Impairment Assessment Questionnaire (CIA). The semi-structured interview using the Eating Disorder Examination Interview (EDE) was conducted for participants with two or more SCOFF scores. Within two weeks, the web-based K-EDDS, the EDE-Q, and the CIA were re-tested. Results : In the exploratory factor analysis, four factors were extracted : body dissatisfaction, binge behaviors, binge frequency and compensatory behaviors. The four subscales of the web-based K-EDDS had significant correlation with each of the four subscales of the EDE-Q. The internal consistency of the web-based K-EDDS was highly satisfactory (Cronbach's alpha=0.93). The diagnostic agreement between the web-based K-EDDS and the EDE was excellent (96.83%), and the web-based K-EDDS's test-retest diagnostic agreement was fairly good (92.86%). The web-based K-EDDS and the CIA also showed significant differences between patients and general population, supporting discriminant validity. Conclusions : This study suggested that the web-based K-EDDS is a valid tool for assisting diagnosis of eating disorders based on DSM-5 in clinical and research fields.

International Comparative Study on Education for International Understanding(EIU) : Based on the Regional Analysis of Europe, North America, Asia Pacific, and Africa (국제이해교육의 지역별 동향 분석 연구: 유럽·북미·아시아태평양·아프리카를 중심으로)

  • Kim, Hyun-Duk;Kang, Soon-Won;Yi, Kyeong-Han;Kim, Da-Won
    • Korean Journal of Comparative Education
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    • v.27 no.4
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    • pp.127-154
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    • 2017
  • EIU has evolved diversely depending on the national environment and culture on the basis of the philosophy of individual human rights and world peace articulated in the "1974 Recommendation on EIU". However, the global environment surrounding EIU has been changed socially, economically, culturally and ecologically in the 21st century, and therefore it is necessary to raise the following questions: Is the concept of EIU initiated for international understanding and cooperation for world peace in the 20th century still valid in the 21st century? Which direction should we take in order for EIU to be efficient in the globalized world? To answer these questions, this study reviewed and analyzed the historical development and current trends of the EIU in the regions of Europe, North America, Asia Pacific area, and Africa. For the empirical study, thirty-four experts in EIU selected from the four regions were interviewed by the researchers. Based on the interviews and the related literature review, it was found that the diverse terms of EIU were used in the four regions and the focus on EIU was different depending on the geographical, historical and social environment of each region. But, despite of the diversity in terminology in EIU, human rights, peace, equity and social justice which are emphasized by UNESCO, were universally taught in EIU. The EIU in these regions is currently dealt with in school education, social education and lifelong education, and particularly global citizenship allowing multiple identities is importantly treated together with citizenship education. Another important aspect of EIU that was commonly found in these four regions was that global citizenship education for solving global problems was coexistent with the reinforcement of nationalism for the economic competency of each nation in a globalized world. The issue of global inequality was particularly dealt with in EIU, and the teaching of voluntary civic involvement and responsibility were particularly emphasized in EIU. Based on these research findings, the study proposes "glocalism", connecting global issues with local issues for solving global problems, as a new approach to the EIU of the 21st century.

Identification of Bird Community Characteristics by Habitat Environment of Jeongmaek Using Self-organizing Map - Case Stuty Area Geumnamhonam and Honam, Hannamgeumbuk and Geumbuk, Naknam Jeongmaek, South Korea - (자기조직화지도를 활용한 정맥의 서식지 환경에 따른 조류 군집 특성 파악 - 금남호남 및 호남정맥, 한남금북 및 금북정맥, 낙남정맥을 대상으로 -)

  • Hwang, Jong-Kyeong;Kang, Te-han;Han, Seung-Woo;Cho, Hae-Jin;Nam, Hyung-Kyu;Kim, Su-Jin;Lee, Joon-Woo
    • Korean Journal of Environment and Ecology
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    • v.35 no.4
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    • pp.377-386
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    • 2021
  • This study was conducted to provide basic data for habitat management and preservation of Jeongmaek. A total of 18 priority research areas were selected with consideration to terrain and habitat environment, and 54 fixed plots were selected for three types of habits: development, valley, and forest road and ridge. The survey was conducted in each season (May, August, and October), excluding the winter season, from 2016 to 2018. The distribution analysis of birds observed in each habitat type using a self-organizing map (SOM) classified them into a total of four groups (MRPP, A=0.12, and p <0.005). The comparative analysis of the number of species, the number of individuals, and the species diversity index for each SOM group showed that they were all the highest in group III (Kruskal-Wallis, the number species: x2 = 13.436, P <0.005; the number of individuals: x2 = 8.229, P <0.05; the species diversity index: x2 = 17.115, P <0.005). Moreover, the analysis by applying the land cover map to the random forest model to examine the index species of each group and identify the characteristics of the habitat environment showed a difference in the ratio of the habitat environment and the indicator species among the four groups. The index species analysis identified a total of 18 bird species as the indicator species in three groups except for group II. When applying the random forest model and indicator species analysis to the results of classification into four groups using the SOM, the composition of the indicator species by the group showed a correlation with the habitat characteristics of each group. Moreover, the distribution patterns and densities of observed species were clearly distinguished according to the dominant habitat for each group. The results of the analysis that applied the SOM, indicator species, and random forest model together can derive useful results for the characterization of bird habitats according to the habitat environment.

Liquefaction Resistance of Gravel-Sand Mixtures (자갈-모래 혼합토의 액상화 거동)

  • Kim, Bang-Sig;Kang, Byung-Hee;Yoon, Yeo-Won
    • Journal of the Korean Geotechnical Society
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    • v.23 no.10
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    • pp.47-56
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    • 2007
  • In this research, the effects of the gravel content on the liquefaction behavior for both of the isotropically and $K_0-anisotropically$ consolidated gravel-sand mixtures are investigated. for this purpose, the cyclic triaxial tests for the specimens with the same relative density (Dr=40%) and variations of gravel content were performed. On the other hand, a series of undrained cyclic triaxial tests were carried out on the isotropically consolidated gravel-sand mixtures with the same void ratio (e=0.7) and from 0% to 30% gravel contents. Void ratios of gravel-sand mixtures with the same relative density (Dr=40%) are found to decrease significantly with the increase of the gravel content from 0% to about 70% and increase thereafter. But the void ratio of the sand matrix among the gravel skeleton increases with the increase of the gravel contents. Test results are as follows : for the isotropically consolidated specimen with 40% of relative density and low gavel contents (GC=0%, 20%, 40%), pore water pressure development and axial strain behavior during undrained cyclic loading show similar behavior to those of the loose sand because of high void ratio, and the specimens with high gravel content (70%) both pore pressure and strata behaviors are similar to those of dense sand. And the isotropically consolidated specimens with the same void ratio (e=0.7) and higher gravel contents show the same behavior of pore water pressure and axial strain as that of the loose sand, but for the lower gravel content this behavior shows similar behavior to that of dense sand. The liquefaction strength of the isotropically consolidated specimens with the same relative density increases with gravel content up to 70%, and the strength decreases with the increase of the gravel content at the same void ratio. Thus, it is confirmed that the liquefaction strength of the gravel-sand mixtures depends both on relative density and void ratio of the whole mixture rather than the relative density of the sand matrix filled among gravels. On the other hand, the behavior of pore water pressure and axial strain for the $K_0-anisotropically$ consolidated gravel-sand mixtures shows almost the same cyclic behavior of the sand with no stress reversal even with some stress reversal of the cyclic loading. Namely, even the stress reversal of about 10% of cyclic stress amplitude, the permanent strain with small cyclic strain increases rapidly with the number of cycles, and the initial liquefaction does not occur always with less than maximum pore water pressure ratio of 1.0. The liquefaction resistance increases with the gravel contents between 0% and 40%, but tends to decrease beyond 40% of gravel content. In conclusion, the cyclic behavior of gravel-sand mixtures depends on factors such as gravel content, void ratio, relative density and consolidation condition.

A Study on the Types of Dispute and its Solution through the Analysis on the Disputes Case of Franchise (프랜차이즈 분쟁사례 분석을 통한 분쟁의 유형과 해결에 관한 연구)

  • Kim, Kyu Won;Lee, Jae Han;Lim, Hyun Cheol
    • The Korean Journal of Franchise Management
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    • v.2 no.1
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    • pp.173-199
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    • 2011
  • A franchisee has to depend on the overall system, such as knowhow and management support, from a franchisor in the franchise system and the two parties do not start with the same position in economic or information power because the franchisor controls or supports through selling or management styles. For this, unfair trades the franchisor's over controlling and limiting the franchisee might occur and other side effects by the people who give the franchisee scam trades has negatively influenced on the development of franchise industry and national economy. So, the purpose of this study is preventing unfair trade for the franchisee from understanding the causes and problems of dispute between the franchisor and the franchisee focused on the dispute cases submitted the Korea Fair Trade Mediation Agency and seeking ways to secure the transparency of recruitment process and justice of franchise management process. The results of the case analysis are followed; first, affiliation contracts should run on the franchisor's exact public information statement and the surely understanding of the franchisee. Secondly, the franchisor needs to use their past experiences and investigated data for recruiting franchisees. Thirdly, in the case of making a contract with the franchisee, the franchisor has to make sure the business area by checking it with franchisee in person. Fourthly, the contracts are important in affiliation contracts, so enacting the possibility of disputes makes the disputes decreased. Fifthly, lots of investigation and interests are needed for protecting rights and interests between the franchisor and franchisee and preventing the disputes by catching the cause and more practical solutions of the disputes from the government.

A Study on the Development of Ultra-precision Small Angle Spindle for Curved Processing of Special Shape Pocket in the Fourth Industrial Revolution of Machine Tools (공작기계의 4차 산업혁명에서 특수한 형상 포켓 곡면가공을 위한 초정밀 소형 앵글 스핀들 개발에 관한 연구)

  • Lee Ji Woong
    • Journal of Practical Engineering Education
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    • v.15 no.1
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    • pp.119-126
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    • 2023
  • Today, in order to improve fuel efficiency and dynamic behavior of automobiles, an era of light weight and simplification of automobile parts is being formed. In order to simplify and design and manufacture the shape of the product, various components are integrated. For example, in order to commercialize three products into one product, product processing is occurring to a very narrow area. In the case of existing parts, precision die casting or casting production is used for processing convenience, and the multi-piece method requires a lot of processes and reduces the precision and strength of the parts. It is very advantageous to manufacture integrally to simplify the processing air and secure the strength of the parts, but if a deep and narrow pocket part needs to be processed, it cannot be processed with the equipment's own spindle. To solve a problem, research on cutting processing is being actively conducted, and multi-axis composite processing technology not only solves this problem. It has many advantages, such as being able to cut into composite shapes that have been difficult to flexibly cut through various processes with one machine tool so far. However, the reality is that expensive equipment increases manufacturing costs and lacks engineers who can operate the machine. In the five-axis cutting processing machine, when producing products with deep and narrow sections, the cycle time increases in product production due to the indirectness of tools, and many problems occur in processing. Therefore, dedicated machine tools and multi-axis composite machines should be used. Alternatively, an angle spindle may be used as a special tool capable of multi-axis composite machining of five or more axes in a three-axis machining center. Various and continuous studies are needed in areas such as processing vibration absorption, low heat generation and operational stability, excellent dimensional stability, and strength securing by using the angle spindle.

Bathymetric and Topographic Changes of the Gomso-Bay Tidal Flat, West Coast of the Korean Peninsula (한반도 서해안 곰소만 갯벌의 수심 및 지형 변화)

  • Jin Ho Chang;Yong-Gil Kim;Myong Sun Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.6
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    • pp.552-561
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    • 2023
  • The seafloor topography of Gomso Bay on the west coast of Korea was investigated using subtidal bathymetry and tidal-flat altimetry. Gomso Bay consists of 80% tidal flats and 20% subtidal zone, and is divided into an outer bay and an inner bay by the Jujincheon esturary channel. The outer bay tidal flat, has few tidal channels, has a concave topographic profile, and is characterized by the development of chenier and intertidal sand bars, giving it the appearance of gently sloping, dissipative beaches. The inner bay tidal flat has wide upper and middle tidal flats with a well-developed tidal channel system without cheniers. Moreover, the topographical cross-section between these tidal channels is convex upward, and shows the characteristics of a depositional environment greatly influenced by tidal channels and tidal action. An analysis of the horizontal movement of the tidal flat environment over the past 37 years investigating changes in the iso-depth lines in the Gomso-Bay tidal flat between 1981 and 2018 revealed that the Gomso-Bay tidal flat retreated gradually landward. As a result of analyzing the erosion and sedimentation characteristics of Gomso Bay, assuming that most of the water depth changes were due to changes in the elevation of the sea floor and sea level, an average of 1 cm (0 mm/y) of sediment was eroded in the outer bay over the past 37 years (1981-2018), In the inner bay, an average of 50 cm (14 mm/y) was deposited. Notably, the high tidal flats of the outer bay were largely eroded. Monitoring photographs of the coast showed that most of the erosion of the high tidal flats in the outer bay occurred in a short period around 1999 (probably 1997-2002), and that the erosion resulted from the erosion of sand dunes and high-tide beaches caused by temporarily greatly raised high tide levels and storms.

Characteristics of Plant Community Structure for Vegetation Management Planning of Bonguisan Neighborhood Park, Chuncheon City (춘천시 봉의산근린공원의 식생관리방안을 위한 식물군집구조 특성 연구)

  • Lee, Eun-Seok;Han, Bong-Ho;Kim Jong Yup;Lee, Hak-Gi
    • Journal of the Korean Institute of Landscape Architecture
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    • v.52 no.1
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    • pp.17-33
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    • 2024
  • This study suggests management planning of Bonguisan Neighborhood Park located on the central of Chuncheon city and highly used for citizen's rest and leisure space utilizing its vegetation structure feature. Bonguisan has been the central of the chuncheon since the period of the Three states in Korean history and consistently damaged, especially in present era, an isolation and sererance of its ecosystem has deepen for indiscreet urban development. The percentage of actual vegetation of Boinguisan Neighborhood Park is as follows: Quercus mongolica is 28.5%, Quercus mongolica - Quercus serrata is 2.1%, Pinus densiflora is 15.6%, Pinus densiflora - Quercus mongolica is 15.9%, Betula schmidtii is 1.6%, Robinia pseudoacacia is 5.9%, Pinus koraiensis is 1.6%. Quercus mongolica is distributed on the southwest, northwest, southeast side of region, Pinus densiflora is distributed on the ridge of east and southeast side of region, Betula schmidtii is distributed on the valley of northeast side region and steep slope region which is on the north side of chungwonsa temple. Pinus densiflora community (Comm. I) and Quercus acutissima - Robinia pseudoacacia community (Comm. V) is expected to undergo succession since it's categorized as Quercus spp. and Quercus mongolica community (Comm. II) and Quercus serrata-Quercus mongolica community (Comm. III), Betula schmidtii community (Comm. IV), Pinus koraiensis community (Comm. VI) is expected to maintain. Also for target vegetation and management planning, Vegetation of Bonguisan Neighborhood Park is classified as 1st Natural landscape conservation and improvement type, 2nd Ecological succession type, 3rd Unusual community conservation type, and 4th Recreation and experience type. And we suggested ecological management measure about each management types. For efficient management of Bonguisan Neighborhood Park, it is need to unify management system of it and after designating Pinus densiflora community and Betula schmidtii community which has high ecological preservation value as an ecological landscape protected area and manage it.

Analysis of Micro-Sedimentary Structure Characteristics Using Ultra-High Resolution UAV Imagery: Hwangdo Tidal Flat, South Korea (초고해상도 무인항공기 영상을 이용한 한국 황도 갯벌의 미세 퇴적 구조 특성 분석)

  • Minju Kim;Won-Kyung Baek;Hoi Soo Jung;Joo-Hyung Ryu
    • Korean Journal of Remote Sensing
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    • v.40 no.3
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    • pp.295-305
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    • 2024
  • This study aims to analyze the micro-sedimentary structures of the Hwangdo tidal flats using ultra-high resolution unmanned aerial vehicle (UAV) data. Tidal flats, located in the transitional area between land and sea, constantly change due to tidal activities and provide a unique environment important for understanding sedimentary processes and environmental conditions. Traditional field observation methods are limited in spatial and temporal coverage, and existing satellite imagery does not provide sufficient resolution to study micro-sedimentary structures. To overcome these limitations, high-resolution images of the Hwangdo tidal flats in Chungcheongnam-do were acquired using UAVs. This area has experienced significant changes in its sedimentary environment due to coastal development projects such as sea wall construction. From May 17 to 18, 2022, sediment samples were collected from 91 points during field surveys and 25 in-situ points were intensively analyzed. UAV data with a spatial resolution of approximately 0.9 mm allowed identifying and extracting parameters related to micro-sedimentary structures. For mud cracks, the length of the major axis of the polygons was extracted, and the wavelength and ripple symmetry index were extracted for ripple marks. The results of the study showed that in areas with mud content above 80%, mud cracks formed at an average major axis length of 37.3 cm. In regions with sand content above 60%, ripples with an average wavelength of 8 cm and a ripple symmetry index of 2.0 were formed. This study demonstrated that micro-sedimentary structures of tidal flats can be effectively analyzed using ultra-high resolution UAV data without field surveys. This highlights the potential of UAV technology as an important tool in environmental monitoring and coastal management and shows its usefulness in the study of sedimentary structures. In addition, the results of this study are expected to serve as baseline data for more accurate sedimentary facies classification.