Pressurized Heavy Water Reactors (PHWR) have stored ion exchange resins, which are used in deuteration, dehydrogenation systems, liquid waste treatment systems, and heavy water cleaning systems, in spent resin storage tanks. The C-14 radioactivity concentration of PHWR spent resin currently stored at the Wolseong Nuclear Power Plant is 4.6×10E+6 Bq/g, which exceeds the limited concentration of low-level radioactive waste. In addition, when all is disposed of, the total radioactivity of C-14, 1.48×10E+15 Bq, exceeds the disposal limit of the first-stage disposal facility, 3.04×10E+14. Therefore, it is currently impossible to dispose of them in Gyeongju intermediate- and low-level disposal facilities. As to dispose of spent resins produced in PHWR, C-14 must be removed from spent resins. This C- 14 removal technology from the spent resin can increase the utilization of Gyeongju intermediate- and low-level disposal facilities, and since C-14 separated from the spent resin can be used as an expensive resource, it is necessary to maximize its economic value by recycling it. The development of C-14 removal technology from the spent resin was carried out under the supervision of Korea Hydro & Nuclear Power in 2003, but there was a limit to the C-14 removal and adsorption technology and process. After that, Sunkwang T&S, Korea Atomic Energy Research Institute, and Ulsan Institute of Science and Technology developed spent resin treatment technology with C-14-containing heavy water for the first and second phases from 2015 to 2019 and from 2019 to the present, respectively. The first study had a limitation of a pilot device with a treatment capacity of 10L per day, and the second study was insufficient in implementing the technology to separate spent resin from the mixture, and it was difficult to install on-site due to the enlarged equipment scale. The technology to be proposed in this paper overcomes the limitations of spent resin mixture separation and equipment size, which are the disadvantages of the existing technology. In addition, since 14CO2 with high concentration is stored in liquid form in the storage tank, only the necessary amount of C-14 radioactive isotope can be extracted from the storage tank and be used in necessary industrial fields such as labeling compound production. Therefore, when the facility proposed in this paper is applied for treating mixtures in spent resin tanks of PHWR, it is expected to secure field applicability and safety, and to reflect the various needs of consumers of labeled compound operators utilizing C-14.

The Korean Air-Force aircraft maintenance depot paints the exterior of various aircraft, including high-tech fighters. Aircraft exterior painting is a maintenance process for long-term life management by preventing damage to the aircraft surface due to corrosion. The de-painting process is essential to ensure the quality of aircraft exterior paints. However, because the Korean Air-Force’s de-painting process is currently done with sanding or Plastic Media Blasting (PMB) method, it is exposed to harmful dust and harmful compounds and consumes a lot of manpower. This study compares the de-painting process currently applied by the ROK Air-Force and the more improved process of the US Air Force, and performs economic analysis for the introduction of advanced equipment. It aims to provide information that can determine the optimal time to introduce new facilities through Cost-Volume-Profit (CVP) analysis. As a result of the analysis, it was confirmed that the sanding method had the most economical efficiency up to 2 units per year, the PMB method from 3 to 21 units, and the laser method from 22 units or more. In addition, in a situation where the amount of de-painting work is expected to increase significantly due to the increase in fighters in future, BEP analysis was conducted on the expansion of the existing PMB method and the introduction of a new laser method. As a result of the analysis, it was confirmed that it is more economical to introduce the laser method when the amount of work exceeds the PMB work capacity(18 units per year). The paper would helpful to improve the productivity and quality of the Korean Air Force Aircraft maintenance depot through timely changes of facilities in the workplace in preparation for expansion.

The most important thing to successfully restore an oak forest is finding suitable climatic conditions and topographic factors for the oak species to be introduced. In this study, in order to find suitable environmental conditions for the five dominant oak trees on the Korean Peninsula, we carried out analysing the information on the location of forest vegetation on the Korean Peninsula. The range of annual mean temperature of the five oak trees was narrow in the order of Q. mongolica (7.7~14.3°C), Q. variabilis (9.2~13.8°C), Q. acutissima (10.5~14.3°C), Q. serrata (11.4~13.7°C), Q. aliena (11.0~12.9°C). The range of annual precipitation of oaks was narrow in order of Q. mongolica (1072.7~1780.9 mm), Q. variablis (1066.6~1554.9 mm), Q. acustissima (1036.5~1504.8 mm), Q. serrata (1062.6~1504.7 mm). The range of altitude was in order of Q. mongolica (147~1388 m), Q. serrata (93~950 m), Q. variabilis (90~913 m), Q. acustissima (60~516 m), Q. aliena (55~465 m). The range of slope was in the order of Q. mongolica (8~56°), Q. variabilis (5~52°), Q. serrata (11~45°), Q. aliena (15~38°), Q. acustissima (16~37°). These results are considered to be very useful in the case of ecological restoration using deciduous oak trees on the Korean Peninsula.

The emergence of green methods for the synthesis of graphene-based composites became the gateway for the solution of pollution and economic synthetic methods. Herein, we reported a single step in situ synthesis of reduced graphene oxide sheets decorated with silver nanoparticles (CRG–Ag nanocomposite) using custard apple leaf extract as an effective reducing and stabilizing agent. The ultraviolet–visible, Fourier transform infrared and Raman techniques revealed a primary confirmation about the formation of the said nanocomposite. The X-ray diffraction studies confirmed the face-centred cubic crystal structure of silver nanoparticles (Ag NPs) of 30 nm in size. The high-resolution scanning electron microscope spectra revealed the uniform distribution of Ag NPs on the graphene sheets. This simple, novel and rapid approach enabled a facile production of homogeneously deposited Ag NPs on graphene sheets. Thus synthesized CRG–Ag nanocomposite showed excellent photocatalytic efficiency of 96% in 2 h under sunlight using methylene blue as a model pollutant.

The private sector is currently reviewing the feasibility of the project or deciding economic policies by analyzing the economic ripple effects. However, the arms acquisition project focuses on the need for the national defense weapons system by analyzing the costs and the effectiveness of the analysis and reviewing the necessity and feasibility of the project. In order to analyze the economic ripple effects, KB (the Bank of Korea) prepares and publishes an analysis table of industrial associations in a given unit. IAAR (the industrial association analysis report) is difficult to apply directly to the defense weapons system. Therefore, research on the economic ripple effects applicable to the defense arms procurement project was needed. In this study, we propose the generic methodology for estimating economical and technical ripple effects resulted in acquiring new weapon systems. Based on the analysis of inter-industrial relations, economical ripple effects are estimated with production inducing effects, value-induced effects, employment-induced effects and export-induced effects. Also, the technological ripple effects are estimated with technological intensity represented by investment cost in research and development. To show the validity of proposed methodology, a case study of acquiring new weapon systems such as GR (guided rocket), destroyer, and helicopter is accomplished. From the case study, it is concluded that these economical & technological ripple effects can be used as a reference to decision making in the course of acquiring major future defense weapons systems.

본 연구의 목적은 서산·태안 지역에서 마늘 생산량에 영향을 주는 기상 및 기후 인자를 파악하고 농가의 기후 정보이용에 따른 경제적 가치를 분석하는 것이다. 이 지역에서 기후 특성과 경향이 1984-2013년의 서산지방기상청 기상자료, 1989-2013년의 마늘 생산량 국가통계자료, 2001-2100년간의 기후변화 시나리오 자료(RCP 4.5, 8.5)와 함께 분석되었다. 연구 결과는 다음과 같다. 첫째, 서산·태안 지역에서 겨울철 평균기온과 평균풍속이 다른 마늘 재배 지역에 비해 낮고 강하여 마늘 성장을 위한 저온 조건을 만족하였고, 5월의 누적강수량이 감소하여 한지형 마늘이 생육하기에 적합한 것으로 나타났다. 하지만 마늘의 수확기 때 평균기온, 누적강수량 및 평균풍속 등의 증가추세로 인해 미래 한지형 마늘 재배지는 줄어들 것이다. 둘째, 서산·태안 지역에서 기후변화 시나리오(RCP 4.5, 8.5)를 이용한 한지형과 난지형 마늘 모두 파종적기는 현재보다 늦어지고 수확적기는 빨라지며, 추후 100년 동안 재배기간이 50-90일 정도 짧아지는 것으로 나타난다. 셋째, 마늘 흑색썩음균핵병과 고자리파리의 발생 시작 일이 평균기온(oC)과 토양습도(%)를 이용한 기상 알고리즘을 적용함으로서 산출되었다. 특별히 RCP 4.5와 RCP 8.5 시나리오에서 미래 마늘 흑색썩음균핵병 발생 일은 모두 현재보다 앞당겨 지는 것으로 나타났다. 넷째, 서산·태안지역에서 마늘 생산량(ka/10a)은 월동기 최저기온, 추대기 누적강수량, 월동기 평균풍속, 그리고 추대기 평균상대습도와 높은 상관을 나타내었다. 한편 마늘 재배에 있어 기후정보이용에 따른 마늘 생산량은 총생산량의 약 9%로 경제적 가치가 증가하는 것으로 나타났다.

This study was conducted to determine grazing intensity of growing Korean native goats(Capra hircus coreanae) on mountainous pasture. It was carried out to obtain basic information for improvement of mountainous pasture management and establishing feeding system of Korean native goat. A total of 20 goats were grouped by feeding systems [A mountainous pasture grazing group (Concentrated feed of 1.5% body weight, treatment 1, T1, n=10) and a barn feeding group (TMR, treatment 2, T2), n=10] to conduct study from April to September. The average forage productivity of the mountain pasture was 500.9 ± 61.41 kg/ha. The average dry matter intake in T1 was 0.64 and the calculated grazing intensity was 21 head/ha. In productivity, when the two treatments(T1, T2) were compared, the dry matter intake was about two to three times the difference. The average daily gain per day during the experiment was 63.3 in the mountain pasture and 120 g in barn feeding. When grazing, considering mountainous pasture productivity it is necessary to increase the productivity through proper feeding. The feed costs of black goats raised by grazing on the grassland in the same period showed an average 75% reduction compared to barn feeding. As a result of this study, it can be expected that a considerable reduction of feed costs can be expected in the breeding of Korean native black goat using the mountain pasture.

Historically, the two major aspects of road design have been (i) The design principles – like AASHTO 1993 Empirical Design or lately, Mechanistic Empirical Pavement Design Method (MEPDM) (ii) The materials & technologies of pavement construction The fundamental design principles have not undergone major changes, however, the advancement in materials and technologies have improved tremendously over last few decades and this makes it necessary to revisit some of the conventional concepts in road design. The new technology now challenges the conventional wisdom and has brought us to the threshold of an era of all new sustainable green roads of tomorrow. AASHTO 1993 Empirical Pavement Design is the basis for pavement design today; in most parts of the world. In some parts of the world, there is a movement towards Mechanistic Empirical Pavement Design Guideline (MEPDG), but the movement is slow and gradual as this approach is expensive and heavily dependent on software programs due to its inherent computational complexities. The concept of Structural Number and Layer Coefficients of pavement layers under AASHTO 1993 Empirical Pavement Design was derived from AASHO road test carried out in Ottawa, Illinois between 1958 & 1960. The conventional Layer Coefficient value of 0.44 which is used today was recommended considering the strength of the construction materials available at that time. But, in view of the new technology available now, this needs to be revisited. Secondly, AASHTO 1993 Empirical Pavement Design provides for assuming certain values for Drainage Coefficients, ranging between 0.4 to 1.4, based on certain criteria. It is quite common to assume a value of 1 for drainage coefficient, in most parts of the world. Now, with the advent of new nanotechnology for waterproofing of road layers, it is possible to consider higher values for drainage coefficients. The new nanotechnology for soil stabilization can make subgrade soils well bonded, strong and flexible, allowing the designer to assume higher values of Resilient Moduli in the AASHTO 1993 design equation, which may bring the required structural number down and allow a lighter design of cross-section of structural layers on top of the subgrade. Indicative calculations for a typical 100 MSA, two lane (10 m wide) highway show that the new technology, while remaining within the AASHTO 1993 design guidelines, enables designing a pavement that is 3 times better (it will now be a 300 MSA pavement instead of 100 MSA) with a cost reduction of about USD 114000 per km. This paper takes an overview of latest trends in USA regarding pavement design approaches. It also puts forth, the opportunities presented to a pavement designer, by the new nanotechnology and proposes a new design approach, for optimized pavement design - green, sustainable & economical; while remaining within the AASHTO 1993 guidelines or MEPDG.

This study develops a model to estimate the economic life of the large-diameter water supply pipeline in Korea by supplementing existing methods used to perform similar calculations. To evaluate the developed methodology, the model was applied to the actual target area with the conveyance pipe in P waterworks. The application yielded an economic life computation of 39.7 years, considering the cost of damages, maintenance, and renewal of the pipeline. Based on a sensitivity analysis of the derived results, the most important factor influencing the economic life expectancy was the predicted failure rate. The methodology for estimating the economic life of the water supply pipeline proposed in this study is one of the core processes of basic waterworks facility management planning. Therefore, the methods and results proposed in this study may be applied to asset management planning for water service providers.

본 연구는 파라과이에 대한 조림투자의 경제적 타당성을 분석하기 위하여 수행되었다. 한국은 목재자 급률이 낮아 90년대 초반부터 적극적인 해외조림투자에 나서고 있으나, 그 투자의 대부분이 동남아시아 에 집중되어 있다. 이러한 상황에서 조림목 생장이 우수하고 적극적인 조림 지원 정책을 추진하고 있는 파라과이는 한국의 해외조림투자 대상지로서 훌륭한 대안이 될 수 있다. 하지만 지구 반대편이라는 지 정학적 위치에 대한 거리감으로 인하여 한국기업은 파라과이 해외조림투자에 대하여 적극적으로 검토하 지 않고 있다. 파라과이 조림투자에 대한 정보가 부족한 것도 기업의 접근을 막는 하나의 요인이며, 우 선적으로 조림사업의 수익성에 대한 자료가 요구된다. 본 연구에서는 파라과이 해외조림투자를 파라과 이 내수 시장에서의 원목 판매와 현지 위탁가공 후 한국시장으로의 제재목 수출, 두 가지 경우에 대하 여 경제적 타당성을 분석하였다. 그 결과, 두 시나리오 모두 높은 경제적 타당성을 가지고 있는 것으로 분석되었다. 원목의 내수시장 판매의 경우, IRR 9.64%, NPV U$ 2,811,888로 나타났다. 제재목 한국 수출의 경우, IRR은 17.51%로 현지원목판매 대비 7.87%p 상승하였고, NPV는 U$ 38,260,086로 현지 원목판매 대비 U$ 35,448,198 상승하였다. 본 연구는 원거리라는 점으로 인해 외면 받아온 남미, 특히 파라과이 조림 진출에 대한 가능성을 새롭게 분석한 것에 큰 의의가 있다하겠다.

This paper analyzed economic feasibility of aquacultural construction which of large-scale. The results of the economic analysis, cage cultural and water recycling cultural by post-water treatment were analyzed that NPV is 2,083,685 thousand won and －14,105,896 thousand won and B/C ratio is 0.590 and 0.855, respectively. These were shown economic infeasibility. But, running water culture by pre-water treatment(small scale) and running water culture by pre-water treatment(large scale) were analyzed that the one is 5,555,747 thousand won and 15,048,589 thousand won and the other is 1,154 and 1,1221, respectively. these were shown economic feasibility. In addition, measurement of B/C ratio through a sensitivity analysis on running water cultural by prewater treatment(small scale) and running water cultural by pre-water treatment(large scale) is economic feasibility in all cases. However, these were analyzed when the selling price was falling to 20 percent, it has shown economic infeasibility and when the selling price rises to 20 percent, water recycling culture by post-water treatment has economic feasibility. The significance of the study analyzed a sensibility as well as economic feasibility by methods and scales. It is expected that used as basic materials when constructing and operating of land aquaculture in order to minimize the damage from natural disasters.

This study is aimed to analyze economical meaning and problems on the industrial differentiation of Korean laver industry. Based on the surveyed data, the export value of korean laver has increased over 28 times for last 20 years($10 million to $300 million) and the separation of farming and processing was an important success factor of rapid growth of korean laver industry. However, the result of the survey shows that the farming profit is 534.1 won out of the total price for a bunch of dried laver, 3,566.3 won. So, farming profit counts for just 15 percent of total price. In contrast, the processing profit is 1,143.5 won and it is 32.1 percent of total price. This means that laver farmers are not being guaranteed their profit properly. This phenomenon is occurred due to lower status of first-hand processors(which produce dried laver) to second-hand processors(which produce seasoned laver) due to advanced payment given by second-hand processors. So, fist-hand processors should provide their product in the price which was designated by second-hand processors. Besides, despite of many business risks caused from climate change and environmental pollution, the market price of raw laver has steadily decreased. For sustainable prosperity of korean laver industry, imbalance on korean laver industry concerning profit sharing is need to be changed. In future, self-processing of dried laver in fishery household and enhancing the role of The Fisheries Cooperative Union in laver industry can be considered.

이 연구의 목적은 경제림육성단지를 대상으로 등급을 구분하고 이를 수치지도화 함으로써 향후 경제 림육성단지 관리를 위한 자료를 제공하는 데 있다. 이를 위해서, 경제림육성단지의 특성을 살펴보고, 등급구분 방안을 마련하고 적용함으로써 최종적으로 경제림육성단지 등급구분 결과를 제시하였다. 산림 기능평가도 중 목재생산기능도와 산지구분도상의 공익용산지를 이용하여 GIS 중첩분석기능 통해 경제 림육성단지를 Ⅰ·Ⅱ·Ⅲ등급으로 구분하였다. 경제림단지에서 먼저 목재생산기능이 높은(고) 지역을 추출하여 Ⅰ등급으로 구분하고, 기타 보통(중)·낮음(저) 지역에 해당하는 곳은 Ⅱ등급으로 하였다. 다 음으로 공익용산지에 해당하는 곳은 Ⅲ등급으로 재추출하였다. 전국적으로 경제림육성단지의 등급구분 결과 Ⅰ등급 2,083천 ha(71.9%), Ⅱ등급 499천 ha(17.2%), Ⅲ등급 267천 ha(9.2%)로 나타났다. 2103 년 선도 산림경영단지로 지정된 홍천, 진안, 보성 3개 단지를 대상으로 경제림육성단지 등급구분 결과 를 비교했을 때 대부분 I등급지에 해당하는 것으로 나타났다. 따라서 경제림육성단지 등급구분 결과는 추후 선도 산림경영단지 지정을 위한 근거자료로 활용할 수 있으며, 생산성이 높은 경제림육성단지를 집중 육성할 수 있는 토대가 될 것이다.

선박의 운항에 소요되는 운항비는 선박의 종류, 크기, 속력, 항행구역 등에 따라 다를 수 있지만, 연료비가 차지하는 비율은 50~60 %에 달하는 것으로 알려져 있다. 최근 국제 유가의 상승으로 인한 선박 운용비를 절감하기 위하여 중소형 선박에서도 저질연료유의 사용이 검토되고 있는 추세이다. 더 나아가 해운선사들은 연료소모량을 줄이기 위한 방법으로 감속운항을 취하고 있다. 따라서, 본 연구에서는 실선을 이용하여 해상에서의 선속대비 주기관의 연료소모량을 계측하고, 부하에 따른 전진계수 대비 속력과 연료소모량의 관계를 통해 상용연속출력보다 낮은 주기관 부하의 70 % 영역이 최적의 운항조건이라고 제안하였다.

Companies strive for quality improvement and use process data obtained through measurement process to monitor and control the process. Measurement data contain variation due to error of operator and instrument. The total variation is sum of product variat

2008년부터 2010년까지 3년간 인삼재배 29농가를 대상으로 묘삼 이식기종별 경제성을 분석, 손익분기 규모를 추정하여 인삼재배농가의 생력화를 위한 기초 자료로 제공하고자 연구한 결과를 요약하면 다음과 같다. 1. 묘삼이식기종에 따른 이식작업의 생력화율은 관행이식 대비 모종이식기 16%, 기계이식기은 49%, 기계이식기는 63%정도의 노력이 절감되었다. 2. 묘삼 이식기에 따른 손익분기 규모를 분석한 결과, 관행이식 대비 기계이식기은 보조지원을 받지 않는 경우 0.9 ha, 기계이식기은 1.3 ha 정도에서 손익분기점이 나타났다.

Companies strive for quality improvement and use process data obtained through measurement process to monitor and control the process. Measurement data contain variation due to error of operator and instrument. The total variation is sum of product variation and measurement variation. Gage R&R is for repeatability and reproducibility of measurement system. Gage R&R study is usually conducted to analyze the measurement process. In performing the gage R&R study, several parameters such as the appropriate number of operators (o), sample size of parts (p), and replicate (r) are used. In this paper we propose how to determine the optimal combination of number of operators (o), sample size of parts (p), and replicates (r) considering measurement time and cost by statistical method.