• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.2
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• pp.214-219
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• 2012

초음파전파영상화(UPI) 시스템은 2007년에 첫 논문 발표를 통해 시스템 개발이 보고된 이후 소프트웨어 및 하드웨어적 측면에서 다양한 형태로 발전된 시스템의 개발이 이루어졌다. 본 기고에서는 기본 UPI 시스템, 섬유파트랜스듀서 UPI 시스템, 순수광학시스템으로서 광섬유 센서 UPI 시스템, 완전비접촉 시스템으로서의 공기정압압전센서 UPI 시스템 및 레이저도플러진동계 UPI 시스템, 장거리 UPI 시스템, 옥외 적용성에 필수적인 저온환경 UPI 시스템 등을 소개한다.

• Aerospace Industry
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• s.108
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• pp.66-67
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• 2010

수직이착륙, 영어로는 VTOL(Vertical Take-Off and Landing)이라 불리는 기술은 공기역학을 거부한 첨단 항공우주기술이다. 일반적으로 고정익 항공기는 날개에서 발생하는 양력으로 하늘을 날지만 VTOL 항공기는 순수한 엔진 추력만으로 수직으로 이착륙하거나 단거리에서 이륙할 수 있다. 다만 높은 기술적 완성도를 요구하는 만큼 현재까지 실전 배치된 군용기 중 이 기술이 적용된 군용기는 해리어(Harrier)와 V-22 오스프리(Osprey), Yak-38 정도가 고작이다. 수직이착륙 기술에 대해 소개한다.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.248-253
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• 2015

This study applied the portfolio approach as a means to provide decision-making information for the establishment of the optimal production plan for non-timber products. The target items of non-timber forest product were Chestnut, Jujube, Walnut and Astringent Persimmon. The data used in this study were the annual report of forestry production cost survey which contains the annual production, annual gross income, and annual product cost from 2008 to 2013. These data were used to calculate the expected return of non-timber forest product. The objective function in the portfolio models was to minimize the expected return volatility, called risk and the constrain was to achieve the minimum expected return rate. Results indicated that the production ratio of the nuts and fruits in 2013 was 7% for Chestnut, 20% for Jujube, 5% for Walnut and 68% for Astringent Persimmon. Furthermore, portfolio presented that the production ratio was 10% for Chestnut, 9% for Jujube, 3% for Walnut and 78% for Astringent Persimmon in the near future. The cause was analyzed due to maintain stable production and income of Astringent Persimmon and Chestnut. Meanwhile, the revenue of Walnuts and Jujube was in great variation with relatively higher revenues.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.649-656
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• 2015

The objective of this study was to analyze the optimal thinning regimes for timber or carbon managements in Cryptomeria japonica stands of Hannam Experimental Forest, Korea Forest Research Institute. In solving the problem, PATH algorithm, developed by Paderes and Brodie, was used as the decision-making tool and the individual-tree/distance-free stand growth simulator for the species, developed by Kwon et al., was used to predict the stand growth associated with density control by thinning regimes and mortality. The results of this study indicate that the timber management for maximum net present value (NPV) needs less number of but higher intensity thinnings than the carbon management for maximum carbon absorption does. In case of carbon management, the amount of carbon absorption is bigger than that of timber management by about 6% but NPV is reduced by about 3.2%. On the other hand, intensive forest managements with thinning regimes promotes net income and carbon absorption by about 60% compared with those of the do-nothing option.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.629-647
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• 2018

This study was carried out to investigate the economic value of organic rice production using gelatin chitin microorganisms in eco-friendly complex, Gongsan, Naju city. The soil condition of experiment paddy field was Jeonbuk series and silt loam with a slightly poor drainage. Except for the high effective silicate, the chemical characteristics of soils used were included in the optimum range of paddy soils in Korea. In growth, plant length, tiller number, ear number, and ear length were observed to be higher in conventional paddy fields than organic paddy fields. However, number of grain per panicle and grain filling ratio (%) were higher in organic paddy fields than conventional paddy fields. Incidences of diseases and insect pests were slightly higher in the organic paddy fields. Water weevil, sheath blight, rice leaf roller and rice blast were more occurred in organic paddy field. On the other hand, false smut was higher occurred in conventional paddy field. There was a significant negative correlation between rice sheath blight and rice leaf roller, and rice yield. In the milled rice quality, the quality of organically cultivated milled rices was lower by the increase of broken rice than that of conventionally cultivated milled rices. The quality and palatability of rice were higher in organic cultivation with decreasing of protein content. Net income of conventionally and organically cultivated rice was 360,000 won/10a and 610,000 won/10a, respectively. Premium net income of the organically cultivated rice was 68%.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.46-52
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• 2012

The purpose of this study is to give ROI informations about management status and investment returns to someone who will newly cultivate lycium chinese miller or expand area of its cultivation. In this study, IRR, B/C Ratio and NPV is used for ROI analysis. We basically surveyed fifty two among Lycium Chinese Miller cultivation farmhouses in chief producing districts Chungnam Chungyang, Jeonnam Jindo in Korea from May until September in 2009. Hence, this study surveyed these farmers about production cost, management cost, input labors and materials, land price and etc. by working process to calculate production and operation cost. As the result of farm survey, average selling price of Lycium Chinese Miller is 15,000 won per kg at locals for five years. However, when 3% discount rate is applied, the result of the analysis is B/C Ratios 0.89, which shows unprofitable. Therefore, it is a possible baseline that price of Lycium Chinese Miller is at least 16,800 won per kg with 3.00% IRR and B/C Ratio is 1.00. It could be profitable with about 21.75% income ratio when price of Lycium Chinese Miller is 16,800 won per kg.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2000.05a
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• pp.425-463
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• 2000

본 연구에서는 3단계에 걸쳐 투자하고 있는 초고속 국가망사업에 대해서 과연 사회적으로 경제성을 갖고 있는지 여부를 분석해 보았다. 이를 위하여 첫째, 산업연관모형을 이용하여 초고속 국가망 사업에 투입한 투자액이 유발시킨 부가가치 창출효과와 고용창출효과를 계산하였다. 다음으로 초고속 국가망 사업으로부터 파생되는 초고속 국가망의 기본서비스 수요를 예측하는 방법론을 제시하였다. 셋째, 초고속 국가망으로부터 파생되는 기본서비스 수요 창출로 인하여 향후 2010년까지 얼마만큼의 새로운 부가가치가 창출되고, 새로운 고용이 얼마만큼 창출되는지 여부를 산업연관모형을 통하여 분석하였다. 마지막으로 초고속 국가망 사업에 투자한 총금액에 대비하여 이를 통하여 얻어지는 부가가치창출효과, 고용창출효과 및 수요창출효과 등을 감안하여 과연 초고속 국가망 사업이 얼마만큼 사회적으로 경제성을 지니고 있는지를 계산해 보고자 하였다. 초고속 국가망 사업을 통한 직접적인 유발효과와 부가적인 효과를 모두를 고려하였을 때 예상되는 순수익의 투자수익율은 5439.2%로서 투자액의 54배의 사회적 수익성을 창출한다고 본다. 다음으로 부가가치유발액, 매출이익에 새로운 고용유발로 인한 소득증가분을 감안하여 사회적 수익을 계산하고, 이에 근거하여 경제성 분석을 하면 21,493.3.%와 같이 215배의 사회적 수익성이 창출된다고 계산되어진다. 따라서 간단하게 이익률법에 근거한 초고속국가망 사업에 대한 사회적 편익과 비용에 근거한 경제성 분석을 하면 초고속 국가망 사업은 투자액의 무려 215배의 사회적 편익을 제공하는 것으로 나타났다.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.39-46
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• 2016

The history of Social service is above 10 years. Owing to corresponding to the user's needs social services sector is expanding. And, to deal with them, the social delivery systems has been changed. Traditional social welfare delivery system is provided by public facilities and private facilities. On the other hand, Social Services is made up of the traditional social welfare delivery system and new delivery system which is composed of profit organizations and non-profit organizations. Considering this, Study attempted to compare the performance evaluation of supply type-profit and non-profit social service organizations. Performance evaluation method was applied to net income, except for expenditure in total revenue. Net income difference between profit organization non-profit organization was assessed by T-test. We conclude that the two population means are different at the 0.05 significance level. Looking in detail, the non-profit organizations were found to be higher than the non-profit organizations, labor costs, operating costs, facility cost and consumable costs, but part of the business expense costs, the non-profit organizations was higher than the profit organizations.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.107-112
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• 2013

The purpose of the study is to give ROI information about management status and investment returns to someone who will newly cultivate Rhus verniciflura and expand area of Rhus verniciflura cultivation. In this study, IRR (Internal Rate of Returns), B/C Ratio and NPV are applied for ROI analysis. We basically surveyed thirty household among Rhus verniciflura cultivation farmhouses in chief producing districts Won-ju in Gang- Won, Ok-Cheon in Chung-Buk, Ham-Yang in Gyeong-Nam in Korea from May until October in 2011. Hence, the research surveyed these farmers about production cost, management cost, input labors and materials, land price and etc. by working process to calculate production and operation cost. As the result of farm survey, the result of the analysis shows income rate 27.76%, B/C Ratio 2.5, and NPV 121,830,831 won in $16,500m^2$ with 10 years period when local price of Rhus verniciflura is 2,200,000 won/3.75 kg at locals with 3% discount rate is applied. Therefore, starting open field cultivation of Rhus verniciflura, which requires intensive labor or expanding the cultivation area needs more labor force.

• The Korean Journal of Applied Statistics
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• v.19 no.3
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• pp.407-419
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• 2006

In this paper, we analyze household overdue loans in Korea which has been causing serious social and economical problems. We consider customers of Bank A in Korea and focus on overdue cash services which have been snowballing in the past few years. From analysis of overdue loans, one can predict possible delays for current customers as well as build a credit evaluation and risk management system for future customers. As a statistical analytical tool, we propose a two-stage Generalized Linear regression Model (GLM) which assumes a logistic model for presence/non-presence of overdue and a gamma model for the amount of overdue in the case of overdue. We perform goodness of fit test for the two-stage model and select significant explanatory variables in each stage of the model. It turns out that age, the amount of credit loans from other financial companies, the amount of cash service from other companies, debit balance, the average amount of cash service, and net profit are important explanatory variables relevant to overdue credit card cash service in Korea.