• Journal of Plant Biotechnology
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• 제7권3호
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• pp.155-160
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• 2005

Haloxylon recurvum (Locally known as Khar) is drought and salt tolerant plant of Thar Desert. This plant is a major biomass producer and has economic and ecological importance for the region. There is need for study on biology, propagation and genetic improvement for utilization of this plant for reclamation of saline soils. We report here on in vitro propagation of Haloxylon recurvum (Moq.) using nodal explant. Secretion of phenolic compound from explants was a major constraint for establishment of culture. This was checked by thorough washing and quick transfer of explant on fresh culture medium. Juvenile nodal explant with leaves was found suitable for culture establishment. Benzy-ladenine($4.0\;{\mu}M$) incorporated in Murashige and Skoog (MS) medium with additives (50 mg/L ascorbic acid and 25 mg/L each of adenine sulphate, arginine and citric acid) induced multiple shoots from nodal explant. Addition of $1.0\;{\mu}M$ naphthalene acetic acid (NAA) in combination with $4.0\;{\mu}M$ BAP improved the growth of axillary shoots. Further shoot amplification was achieved by repeated subculture of mother explants on fresh medium. Forty percent of the micropropagated shoots rooted on half-strength MS medium with $4.0\;{\mu}M$ indolebutyric acid (IBA) and 100 mg/L activated charcoal, at $28{\pm}2^{\circ}C$ and $60\%$ RH. Sixty percent of these plantlets were hardened in green house.

• 토지주택연구
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• 제11권2호
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• pp.1-14
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• 2020

The aim of this study is to empirically identify the differentiating characteristics of determinant factors on sing-person households' commuting mode choice compared to multi-person households' one in order to establish the customized police directions to decrease private car use in commuting. While the study use the 2% sample survey data on the population and housing in 2015, it employ multinomial logit models on relative choice probability of such alternative commuting modes as bus, subway or rail, and walking, rather than driving. As potential determinant factors, the study employs demographic, socio-economic, and housing and residential one for both models of single-person and multi-person households. The study finds that the behavior of commuting mode choice has distinctive difference by gender, marriage status, physical activity constraint, job type, residential period in current housing of the single-person household's workers compared to the multi-person households' ones. Based on the findings, the study deduce ten commuting policy directions customized for the single-person household.

• Journal of Information Technology Applications and Management
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• 제26권3호
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• pp.135-157
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• 2019

Information technology has economic, social and cultural impacts is closely linked to our lives. This information technology is becoming a key to the change of human civilization through connecting people and objects on the earth. In addition, future information technology is becoming more intelligent and personalized with the development of computing technology, and due to the rapid development of alcohol, environment without time and space constraint is realized, Is spreading. Since existing portable storage media are made of physical form, there is a limit to usage due to the risk of loss and limitation of capacity. Cloud services can overcome these limitations. Due to the problems of existing storage media, it is possible to overcome the limitations of storing, managing and reusing information through cloud services. Despite the large number of cloud service users, the existing research has focused mainly on the concept of cloud service and the effect of introduction on the companies. This study aims to conduct a study on individual characteristics that affect the degree of cloud use. We will conduct research on the causes of IT knowledge, personal perception of security, convenience, innovation, economical trust, and platform dependency affecting the intention to use the cloud. These results show that the variables affecting individual 's use of cloud service are influenced by individuals, and this study can be used as a basic data for individuals to use cloud service.

• KDI Journal of Economic Policy
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• 제17권4호
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• pp.63-95
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• 1995

본(本) 연구(硏究)에서는 가계(家計)가 소비지출시 어느 정도 유동성제약(流動性制約)(liquidity constraint)하에 처해 있는가를 분석하기 위하여 이론적인 모형(模型) 제시와 함께 한국(韓國) 일본(日本) 미국(美國)을 대상으로 실증분석(實證分析)을 시도하였다. 3개국 공히 내구재(耐久財) 소비지출시 비내구재(非耐久財) 소비에 비해 상대적으로 유동성제약 현상이 더 심한 것으로 추정되었다. 특히 우리나라의 소비자들은 내구재와 비내구재 등 모든 형태별 소비지출에 있어서 일본(日本)과 미국(美國)에 비해 더 심한 유동성제약하에 처해 왔던 것으로 나타났다. 1980년대에 들어서는 소비자금융시장에서의 유동성제약(流動性制約)이 점차 완화(緩和)되어 온 것으로 나타났으나, 여전히 일본과 미국의 수준을 크게 상회(上廻)하였다. 이러한 추정결과들은 장기간에 걸친 생산자(生産者) 중심의 금융제도 및 관행 등으로 인해 우리나라의 소비자금융시장(消費者金融市場)이 선진국에 비해 낙후(落後)되어 있음을 반영한다. 위의 분석결과는 향후 할부금융제도(割賦金融制度) 도입 등 소비자금융 규제 완화가 본격화되면 유동성제약(流動性制約)이 완화되어 가계의 차입(借入)과 저축(貯蓄)을 통한 소비의 평탄화(平坦化)(smoothing)가 가능해짐으로써 소비자의 후생(厚生)이 증대되고 경기변동(景氣變動)의 진폭이 축소될 것임을 시사한다. 또한 소비자금융의 활성화는 기존의 유동성제약하에 처해 있었던 가계들의 소비를 촉진시켜 단기적으로는 경제 전체의 저축률(貯蓄率) 하락요인으로 작용할 가능성도 있을 것이다.

• 대한전기학회논문지
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• 제37권5호
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• pp.272-281
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• 1988

The problem of optimal transmission system planning is to find the most economical locations and time of transmission line construction under the various constraints such as available rights-of-way, finances, the technical characteristics of power system, and the reliability criterion of power supply, and so on. In this paper the constraint of right-of-way is represented as a finite set of available rights-of-way. And the constructed for a unit period. The electrical constraints are represented in terms of line overload and steady state stability margin. And the reliability criterion is dealt with the suppression of failure cost and with single-contingency analysis. In general, the transmission planning problem requires integer solutions and its objective function is nonlinear. In this paper the objective function is defined as a sum of the present values of construction cost and the minimum operating cost of power system. The latter is represented as a sum of generation cost and failure cost considering the change of yearly load, economic dispatch, and the line contingency. For the calculation of operating cost linear programming is adopted on the base of DC load flow calculation, and for the optimization of main objective function nonlinear Branch-and-Bound algorithm is used. Finally, for improving the efficiency of B & B algorithm a new sensitivity analysis algorithm is proposed.

• KDI Journal of Economic Policy
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• 제37권1호
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• pp.19-44
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• 2015

This paper examines the effect of the global financial crisis on corporate investment in Korea. Specifically, the crisis was considered to have possibly constrained firm-level investment as the negative shock to the credit supply dramatically unfolded. As Duchin et al. (2010) demonstrated, if a negative supply-side shock is evident during a crisis period, larger cash holdings before the crisis will lead to fewer constraints to corporate investment, or vice versa. In order to investigate the supply-side effect of the crisis, we use firm-level financial data, including firms listed on the Korean stock market as well as small and medium-sized enterprises. We find that corporate investment declined significantly after the crisis, even if we control for factors associated with the demand side, such as contemporaneous capital productivity and cash flow. More importantly, the decline is positively and significantly related to cash holdings before the crisis, implying the negative effect of a credit supply shock. Small and medium enterprises experienced relatively sharp investment declines compared to those of larger firms, and the relationship between pre-crisis cash amounts and the degree of investment decline is greater than that in large firms. Additionally, we examine whether the negative effect persists up to the present, finding evidence that the cash-investment relationship continues in small and medium-sized enterprises.

• 한국해안해양공학회지
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• 제11권1호
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• pp.1-6
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• 1999

해안 및 해양에 설치되어 있는 해저관로는 원유, 가스, 물과 이들의 혼합된 유체들을 전달하기 위한 수단으로 사용되고 있다. 관로 내부 유체의 열과 압력 차이는 해저관로의 팽찰을 야기시킨다. 해전관로 팽창은 관로와 연결되는 구조물들에 응력을 유발시킨다. 작용 응력이 연결 부재의 항복점을 초과하거나 전체 시스템의 허용변형을 초과할 경우 구조물에 손상이 발생된다. 해안 및 해양에 설치되는 해저관로는 주로 위험 물질이나 유독 유체를 포함하기 때문에 만약 이런 유체의 유출이 발생될 경우 인명 피해는 물론 큰 경제적 손실을 가져온다. 비록 해저관로는 시간적/공간적 제약 없이 유체를 전달할 수 있지만, 이런 관로 설계시 안전하게 그 기능을 수행할 수 있도록 고려되어야 한다. 본 논문에서는 해저관로의 열변형 해석에 사용되는 여러 개의 이론을 조사하였고, 관로의 요소들이 관로 팽창에 미치는 영향에 대해 조사하였다.

• 한국국방경영분석학회지
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• 제27권2호
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• pp.88-109
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• 2001

Defense minister of the ROK, Kim Bong-sin suggested that the ROK′s military build-up policy will change from "scenario-based" to "capability-based". Entering the 1990s the ROK′s military build-up policy met difficulties to accomplish its goal, modernizing and strengthening of its force structure and weapon systems because of limited budget. The concept of capability-based military build-up could commit a fault in estimating total amount of defense resources required for force planing. This is because that the total amount of defense resources related to force plan for the 15 years is fixed to embody military strategy. The concept of capability-based military build-up plays a role as a constraint in choosing a military strategy. This has no connection with military build-up. Therefore the resources of mid-term military build-up program and scale of annual defense budget could be affected by the situations of its national economy. In this respect, the scale of annual defense budget and resources could be changed in accordance with national economic condition, however, the total amount of resources required to build-up military force for 15 years, namely resources of military force planing requirement for 15 years, is given already for the accomplishment of military strategy. The purpose of this study is to seek a direction of the ROK′s military build-up policy in a viewpoint of capability-based military build-up.

• 수산경영론집
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• 제49권3호
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• pp.29-47
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• 2018

The primary purpose of this paper is to introduce the cases of fishery co-management, particularly in Korea. In recent, the fishery co-management between the government and fishermen has been brought an important shift of paradigm in a part of Korean fishery management policy. In case of Korea fisheries area, three fisheries cooperatives(which refer to purse sein fishery, trawl fishery, stow net fishery) have a minority of co-management programs. Generally, the main method of fishery co-management programs is 'Fishery Closures' among the programs, and others are restriction of fishing gear and fishermen educations. In spite of the efforts and time consumes of Korean government and fisheries cooperatives, much to our regret that it is hard to confirm visible results in an increased amount of fisheries resources so far because of the time constraint, namely fishery co-management programs have been conducted just since two to three years before. However, what's certain is that fishery co-management programs make it possible to positively effect on both of area in fishermen and fisheries resources. Accordingly, it is necessary that Korean government and fishermen should extend the fishery co-management to other fishery areas as soon as possible we can in order to efficiently reduce administrative costs and effectively reserve fisheries resources.

• The Journal of Asian Finance, Economics and Business
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• 제8권3호
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• pp.741-750
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• 2021

The budget deficit is closely related to expansionary fiscal policy as a fiscal instrument to encourage economic growth. This study aims to apply optimal control theory in the Keynesian macroeconomic model for the economy, so that optimal growth can be found. Macroeconomic variables include GDP, consumption, investment, exports, imports, and budget deficit as control variables. This study uses secondary data in the form of time series, the time period 1990 to 2018. Performing optimal control will result in optimal fiscal policy. The optimal determination is done through simulation, for the period 2019-2023. The discrete optimal control problem is to minimize the objective function in the form of a quadratic function against the deviation of the state variable and control variable from the target value and the optimal value. Meanwhile, the constraint is Keynes' macroeconomic model. The results showed that the optimal value of macroeconomic variables has a deviation from the target values consisting of: consumption, investment, exports, imports, GDP, and budget deficit. The largest deviation from the average during the simulation occurs in GDP, followed by investment, exports, and the budget deficit. Meanwhile, the lowest average deviation is found in imports.