• 한국산림과학회지
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• 제85권3호
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• pp.539-551
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• 1996

본 연구에서는 위치종속조사가법에 의해 소나무임분에서 조사된 자료로부터 임목의 크기 및 경쟁목과의 거리를 함께 고려한 개체목차원의 거리종속경쟁지수와 전통적인 임분차원의 밀도척도를 추정하고 이들을 흉고직경생장과 비교하여 경쟁상태에 대한 설명력을 검토하였으며, 경쟁지수가 영향변수로 고려된 개체목 흉고직경생장식을 유도하였다. 경쟁목선정방법에 있어 경쟁치단각도를 30도로 설정했을 때의 경쟁지수가 흉고직경생장과 기장 높은 상관관계를 보인 반면, 경쟁구역거리는 흉고직경생장추정에 대한 경쟁지수의 설명력에 미미한 영향을 미치는 것으로 나타났다. 개체목별 거리종속경쟁지수에 근거한 대부분의 임분경쟁지수들은 임분의 경쟁상태를 비슷하게 나타내는 것으로 평가되었다. 임령과 지위지수의 영향을 배제한 상태에서의 편상관분석결과 Alemdag의 평균경쟁지수 및 상대공간지수가 흉고직경과 가장 높은 연관성을 나타냈는데, 이중 개체목의 위치를 파악하지 않고도 비교적 손쉽게 파악될 수 있는 상대공간지수가 임분의 평균흉고직경을 추정하는데는 좀더 적합한 것으로 판단되었다. 개체목차원의 거리종속 경쟁지수중에서, 지위 및 흉고직경의 영향을 배제시킨다면 Hegyi의 경쟁지수가 흉고직경생장과 가장 밀접한 영향관계에 있는 것으로 밝혀졌다. 이로부터 Hegyi경쟁지수 및 임령, 우세목수고, 개체목의 흉고직경을 영향인자로 하는 다음과 같은 흉고직경생장식을 유도하였다. $$dbh^{\prime}=3.975362676{\cdot}age^{-1.099274613}{\cdot}ho^{0.199893990}{\cdot}dbh^{0.269430865}{\cdot}HgCI^{-0.353643587}$$ 위의 식은 다른 조건이 같다면 지위지수는 흉고직경생장에 유리한 영향을 미치는 반면 임령 및 경쟁지수의 증가에 의해서는 흉고직경생장이 둔화된다는 일반생장법칙에 부합되어 흉고직경생장식으로 적합하다고 판단되며, 단목생장모델을 위한 함수식으로 활용될 수 있다.

• 건축역사연구
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• 제17권2호
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• pp.27-45
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• 2008

This study examines the details and characteristics of prizewinning plans of Cho-Sun housing plan competition promoted by Daily Cho-Sun Company during Japanese colonial period. The main features of Cho-Sun housing plan competition were that the competition held with an application of popular newspaper readers and a judging committee was composed of only Korean architects, especially Park, Gil-Ryong as the president of the board of examiners. Cho-Sun housing plan competition put ideological factors for the improvement of living as like advancing to the cultured(modem) life, respecting for family life, respecting for privacy of family members and so on. First of all, the competition suggested the direction of the improvement of dwelling spaces which focused on making harmonious home life. This study found common characteristics of prizewinning plans of Cho-Sun housing plan competition as the result. First, Cho-Sun housing plan competition introduced a centralized house plan as a model of the improvement of small-sized houses. Second, architectural orders of western or Japanese style mingled with ones of korean traditional style in prizewinning plans as entrance hall, western style reception room(parlour), maid's room, bathroom for example. And a manner of seating using chairs was brought into the style of living which would be assumed in the prizewinning plans. Third, traditional way of composing dwelling spaces was maintained, receiving the characteristics of dwelling spaces of japanese style simultaneously, which central corridor was put at the heart of house for improving arrangement of rooms and flow lines. Fourth, lavatory and bathroom were placed inside of the house.

• Journal of Korea Trade
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• 제23권2호
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• pp.1-13
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• 2019

Purpose - This paper empirically investigates the competition effect of exports between Korea and China in their common-export markets considering market sophistication. Modern market sophistication includes an importing country's aggregate demand for products of high quality, design, novelty, eco-friendliness, and even IPR protection. Using an empirical analysis to identify the demand for product quality across countries, this paper estimates the effects of market sophistication on the competition between Korean exports and Chinese products. Design/Methodology - Our empirical model considers the relationship between an importing country's consumer sophistication and the export competition between Korea and China. This study employs the existing theoretical framework to identify the aggregate demand for product quality across countries. Using a quite direct measurement (the consumer sophistication index, our analysis investigates the differential effects of Korea's export market sophistication, particularly in markets where Korean exports are in competition with similar Chinese products. Findings - Our main findings can be summarized as follows: the negative effects of the export competition between Korea and China on Korea's exports are stronger in third markets where consumers are less sophisticated while the effects are not as pronounced in markets where consumers are more sophisticated. This result, however, best applies to differentiated goods which significantly vary in product quality. Originality/value - Existing studies focus on the supply side of production and make the assumption that the market preference for export quality is identical across countries. This paper attempts to evaluate the export competition between Korea and China from the demand-side perspective. This area of trade studies is underexplored both empirically and in theory, although the issue has long been important to Korean and world trade.

• Asia pacific journal of information systems
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• 제23권2호
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• pp.67-86
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• 2013

This study first provides a stylized model that captures the essential features of the SC (Social Commerce) business and the competition process. The model focuses on the relationship between key decision issues such as marketing inputs and market value. As more SCs join the industry, they are inevitably faced with fierce competition, which may lead to sharp increase in the total marketing and advertising expenditure. This type of competition may lead the industry away from its optimal development path, and at worst, toward a disruption of the entire industry ecosystem. Such being the case, another goal of this study is to examine the possibility that the ToC (Tragedy of the Commons) may occur in the SC industry. We build game models, each of which assumes homogeneity and heterogeneity of SC providers, respectively, and derive explicit equilibrium solutions from both models. Our basic analysis presents Nash equilibria in both models and shows that SC providers are inevitably faced with fierce competition, which may lead to sharp increase in the total marketing expenses. We also compare the game outcomes with one with a hypothetical social planner who determines the total marketing level that optimizes the entire market value. Then, ToC can be defined to describe the situation where the total marketing efforts exceed the socially optimal level of marketing efforts. In both models, we examine the possibility of the ecosystem disruption and specify the conditions under which ToC may occur. However, the chance of avoiding ToC is higher with heterogeneous players than with homogeneous players. To supplement our analytical results, we develop a simulation model which incorporates a market dynamics based on the gap between actual marketing efforts and socially optimal marketing level. Simulation experiments present some lessons and insights which also confirm out findings from equilibrium analysis. For example, heterogeneity in SC providers alleviates the severity of ToC and makes it faster for survivors to escape from the ToC trap. As a result, the degree of industrial concentration tends to increase, which also explains the 'rich-get-richer' phenomenon observed in some empirical studies on the SC industry. Lastly, based on our analytical and experimental results, we come up with some measures to avoid ToC and overcome the shortcomings intrinsic to the current business model. And further discussions provide strategic implications and policy directions to overcome the possible trap of ToC in this ecosystem, and eventually help the industry to sustainably develop itself toward the next level. To name a few examples of policy measures, regulations on the marketing activities so that the overall marketing expenses cannot go beyond the socially optimal level; institutional guidelines and rules to straightening up the distortions in the way that SC providers view the marketing costs (the current marketing costs are underestimated, thereby encouraging SC providers to increase marketing expenditure); and so on.

• 한국항만경제학회:학술대회논문집
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• 한국항만경제학회 2006년도 국제학술대회
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• pp.1-12
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• 2006

As national economies globalize, demand for intercontinental container shipping services is growing rapidly, providing a potential economic boon for the countries and communities that provide port services. On the promise of profits, many governments are investing heavily in port infrastructure, leading to a possible glut in port capacity, driving down prices for port services and eliminating profits as ports compete for business. Further, existing ports are making strategic investments to protect their market share, increasing the chance new ports will be overcapitalized and unprofitable. Governments and port researchers need a tool for understanding how local competition in their region will affect demand for port services at their location, and thus better assess the profitability of a prospective port. We propose to develop such a tool by extending our existing simulation model of global container traffic to incorporate demand-side shipper preferences and supply-side strategic responses by incumbent ports to changes in the global port network, including building new ports, scaling up existing ports, and unexpected port closures. We will estimate shipper preferences over routes, port attributes and port services based on US and international shipping data, and redesign the simulation model to maximize the shipper's revealed preference functions rather than simply minimize costs. As demand shifts, competing ports will adjust their pricing (short term) and infrastructure (long term) to remain competitive or defend market share, a reaction we will capture with a game theoretic model of local monopoly that will predict changes in port characteristics. The model's hypotheses will be tested in a controlled laboratory experiment tailored to local port competition in Asia, which will also serve to demonstrate the subtle game theoretic concepts of imperfect competition to a policy and industry audience. We will apply the simulation model to analyze changes in global container traffic in three scenarios: addition of a new large port in the US, extended closure of an existing large port in the US, and cooperative and competitive port infrastructure development among Korean partner countries in Asia.

• 한국산학기술학회논문지
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• 제12권5호
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• pp.2067-2077
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• 2011

최근 IT, BT, NT를 중심으로 기술간 융합이 가속화 되고, 다양한 기술이 복합적으로 활용되는 산업분야가 증가하면서 기술간 경쟁관계 분석에 대한 전략적, 정책적 필요성이 커지고 있으나 기술간 동태적 관계를 분석한 연구는 그리 많지 않다. 본 연구는 기술경쟁 관점에서 기술혁신 과정을 다룬다. 특히, 최근 정부가 우리 경제의 새로운 성장 비전으로 발표한 3대 분야 17개 신성장 동력 기술을 대상으로 하여 이들 기술들의 공진화 과정을 분석 한다. 분석을 위해서 대표적 기술혁신 자료인 특허정보를 활용하고, 동태적 경쟁확산모형으로 폭넓게 활용되고 있는 Lotka-Volterra 모형을 적용한다. 연구결과는 기술혁신 과정에 있어 3대 분야 간, 17개 신성장 동력 기술 간, 신성장 기술 내 세부기술 간 동태적 관계를 분석함으로써, 효과적인 국내 기술정책 수립과 연구개발 우선순위 선정 등의 전략적 의사결정에 활용할 수 있을 것으로 기대된다.

• 경영과학
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• 제32권1호
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• pp.83-100
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• 2015

We analyze a duopoly competition when two firms face input cost increases. The objective of this study is to determine the firms' optimal strategy between a price increase and downsizing under conditions of a spatially differentiated market and consumers' diminishing utility on the product size. We develop a theoretical model of two competing firms offering homogenous products using the standard Hotelling model to determine how firms' optimal strategies change when facing input cost increases. In this paper, there are two types of duopoly competitions: symmetric and asymmetric. In the symmetric case, the two firms have the same marginal cost and are producing and selling identical products. In the asymmetric case, the two firms have different marginal costs. The results show that the optimal strategy decision depends on the size of the input cost increase and the cost differences between the two firms. We find that when two firms are asymmetric (i.e., they have different marginal costs), the two firms might choose asymmetric pairs of strategies in equilibrium under certain conditions. When the cost differences between the two firms are sufficiently large and the cost increase is sufficiently small, the cost leader chooses price increase, and the cost-disadvantaged firm chooses downsizing in equilibrium. This asymmetric strategy reduces price competition between two firms, and consumers are better off. When the cost differences between the two firms are sufficiently large, downsizing is the dominant strategy for the cost-disadvantaged firm. The cost-disadvantaged firm finds it more profitable to reduce the product size than to increase its price to reduce price competition, because consumers prefer downsizing to price increases. This paper might be a good starting point for further analytical research in this area.

• 유통과학연구
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• 제15권12호
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• pp.53-60
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• 2017

Purpose - This paper analyzes the effect of the handset subsidy and the Mobile Number Portability subscriber subsidy regulation, which are the main regulation adopted in "Law on the Improvement of the Mobile Terminal Distribution System" (Mobile Terminal Distribution Act), on the social surplus, the consumer surplus and profits of telecommunications carriers. We focus our analysis on whether the service charge competition is stimulated enough so that it can compensate for the loss of subsidies. Research design, data, and methodology - We use simple economic model to assess the impact of the handset subsidy and the Mobile Number Portability subscriber subsidy regulation. Unlike the former researches on this topic, we depart from using Hotelling model, and instead use the switching cost model, which uses switching cost as a parameter of market powers of telecommunications carriers. We also study the effect of the two different regulations when they are adopted both independently and concurrently. Results - If the market powers of telecommunications carriers are over certain threshold, contrary to the regulatory agency's assertion, the service charge competition would not be stimulated enough to compensate for the deduction in the subsidies, and thus the consumer surplus is compromised. Number Portability subsidy, especially, undermines the rival's market power and thus reduces the service charge. On the other hand, the regulations will also increase the profits of telecommunications carriers. However, social surplus is maximized when both of the regulations are present because the regulations reduces the frequency of switching handsets inefficiently. Conclusions - In enacting the Mobile Terminal Distribution Act, the telecommunications regulatory agency asserted that the regulation on subsidies will stimulate service charge competition, and in the long run, enhance the consumer surplus. However, contrary to the regulatory agency's assertion, subsidy regulation, especially the regulation on Number Portability subsidy, reduces consumer surplus. On the other hand, the Mobile Terminal Distribution Act can also increase the profits of telecommunications carriers because it decreases competition among the telecommunications carriers. However, the Mobile Terminal Distribution Act can increase the social surplus because it reduces inefficient switching of handsets.

• 한국통신학회논문지
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• 제33권9B호
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• pp.822-831
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• 2008

본 논문은 국내 인터넷접속서비스 시장의 괄목할 만한 성장을 이해하기 위한 수요의 동태적확산패턴을 분석, 고찰하는 것을 목적으로 한다. 서비스 제공사업자의 경쟁 강도를 반영한 시장구조 측면과 기술간 및 기술내 경쟁을 반영한 기술경쟁 측면을 고려한 인터넷접속서비스의 동태적 확산 과정을 모형화 하여 국내 인터넷접속서비스를 대상으로 실증분석 하였다. 분석결과 기술간 및 기술내 경쟁 그리고 시장경쟁의 강도가 서비스 확산에 양의 결과를 보이고 있음을 통계적으로 확인하였으며, 이에 따른 전략적, 정책적 시사점을 제시하였다.

• 한국통신학회논문지
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• 제32권4B호
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• pp.234-245
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• 2007

MVNO제도는 선발사업자인 MNO가 보유한 필수설비를 후발사업자가 임대하여 무선통신서비스를 제공하는 이동통신시장의 서비스기반 경쟁정책이다. 서비스기반 경쟁정책은 신규사업자에게 설비를 제공하여 시장 내 경쟁을 촉진시키는 장점과 더불어 기존사업자의 투자의욕을 저하시켜 시장성장을 더디게 하는 단점도 동시에 지니고 있다. 경쟁정책의 도입과 적용이 시장구조에 미치는 영향을 고려해볼 때 도입 이전단계에서 면밀한 검토가 이루어져야 한다. 따라서 본 연구에서는 이론모형 설정을 통해 MVNO가 시장효율성에 미치는 파급효과와 효과적인 MVNO 실시방안에 대해 객관적인 분석을 시도해보고자 한다. 이를 위해 Laffont, Rey and Tirole(1998)과 Armstrong(1998)의 모형을 기초로 MVNO의 특성을 반영한 모형을 설정하여 MVNO 제도 도입 후 상호접속료, 시장가격, 수량, 일방접속료 등에 대한 시사점을 도출하였다. 연구결과 MVNO 제도가 도입될 경우 MNO간 담합 유인이 완화되어 가격이 낮아지고 수량이 증가하는 등 정태적 효율성이 향상되는 것으로 나타났다. 구체적인 MVNO의 실행과 관련하여 한 사업자만 MVNO를 실시하는 경우, 두 사업자 모두가 실시하는 경우, MNO와 MVNO를 구조적으로 분리하는 경우의 시장구조를 살펴본 결과 가격과 수량 측면에서 모든 사업자가 MVNO를 실시하는 경우가 가장 효율적인 것으로 나타났다.