• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4552-4567
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• 2014

A (n,t,n) secret sharing scheme is to share a secret among n group members, where each member also plays a role of a dealer,and any t shares can be used to recover the secret. In this paper, we propose a strong (k,t,n) verifiable multi-secret sharing scheme, where any k out of n participants operate as dealers. The scheme realizes both threshold structure and adversary structure simultaneously, and removes a trusted third party. The secret reconstruction phase is performed using an additive homomorphism for decreasing the storage cost. Meanwhile, the scheme achieves the pre-verification property in the sense that any participant doesn't need to reveal any information about real master shares in the verification phase. We compare our proposal with the previous (n,t,n) secret sharing schemes from the perspectives of what kinds of access structures they achieve, what kinds of functionalities they support and whether heavy storage cost for secret share is required. Then it shows that our scheme takes the following advantages: (a) realizing the adversary structure, (b) allowing any k out of n participants to operate as dealers, (c) small sized secret share. Moreover, our proposed scheme is a favorable candidate to be used in many applications, such as secure multi-party computation and privacy preserving data mining, etc.

• Health Policy and Management
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• v.29 no.3
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• pp.374-378
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• 2019

After the announcement of Moon Jae-in Government's plan (Moon's Care) for Benefit Expansion in National Health Insurance in August 2017, it is necessary to monitor the effects of the policy, especially household out-of-pocket payments (OOP). This paper aims to observe the current status and trend of OOP in Korea. Current health expenditure (CHE) was 144.4 trillion won in 2018, which accounts for 8.1% of gross domestic product (GDP) increased 9.7% from the previous year. Although GDP's share of CHE has been close to the average of the Organization for Economic Cooperation and Development (OECD) countries, the public fund's share was 59.8% of the total in 2018, which was lower than the OECD average of 73.5%. OOP's share was 32.9% in 2018, which decreased from 37.4% in 2008. The share of OOP of non-covered services was 20.0% in 2018, which decreased from 22.9% in 2008. The share of cost-sharing with third-party payers was 12.9% in 2018, which decreased from 14.5% in 2008. The OOP of non-covered services was significantly decreased in hospital and inpatient curative care, but the OOP of non-covered services was significantly increased in the medical clinic. The effect of Moon's Care was not showed in OOP through the results of 2017 and 2018, but further monitoring is needed because the Moon's Care is progressing and the observational period is short.

• Journal of Technology Innovation
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• v.22 no.2
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• pp.157-183
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• 2014

This paper examines how the concentration of ownership in firms influences the R&D investment decision and whether the type of a firm's management (i.e, the owner-manager or professional manger) differentiates the relationship between the ownership concentration and R&D investments by using data of Korean pharmaceutical companies between 2004 and 2008. The results show that the share of the largest shareholder and R&D investment have an inverted U-shaped relationship, and whether a CEO is an owner or a professional manager affects the curvature of the inverted U-shaped relationship. Specifically, when a firm's CEO is a professional manager and the share of his stock is small, increase in the CEO's share increases the R&D investment in the larger amount than when a firm's CEO is an owner. This is because the increase in ownership reduces agency cost; However, when the share of his stock is large, the increase in CEO's share decreases R&D investment in the larger amount than when a firm's CEO is an owner. This is because a professional manager gets concerned over excessive risk exposure more than an owner-manager does.

• Journal of the Korea Society for Simulation
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• v.15 no.1
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• pp.77-85
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• 2006

The cost of downloading content from the Internet may be costly for mobile device users using its 3G connection, because the 3G connection cost to download data from the Internet is a function of the amount of data downloaded. This paper introduces an approach in which mobile devices, called peers, form an ad hoc network and share their downloaded content with others. As an example, spectators may want to collect/share information about players and game records in a stadium. In an art gallery, visitors may want to retrieve some background information about the displayed work from the nearby ad hoc network. In an outdoor class, a teacher may download today's topic files from the Internet, and all students may share the content with minimal or no cost paid. This is possible if mobile device has both a 3G interface and a wireless LAN interface. If the peers want to improve privacy md discourage traffic analysis when sharing content, this paper describes a low-delay anonymous connection between the sending peer and the receiving peer using two additional peers. Simulation results show that the transmission time overhead of the anonymous connection may increase 50% or less as the number of peers increase or the peers are scattered over the larger area.

• Food Science and Preservation
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• v.3 no.1
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• pp.61-75
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• 1996

Apple is most favorable fruit in Korea, and apple farmland has been increased before and after the agreements of Uruguay Round and apple is considered as one of strategic agricultural products. Especially expansion of apple farmland is concentrated in Kyungpook region because of the suitable climate and its market share is about 70 percents in 1992. The marketing channels of apples of Kyungpook region are widely classified by merchant, agricultural or horticultural co-op and large scale farmer's. Among them market share of merchant's occupy over 65 percent. In marketing margins, commercial profit is higher than cost in total marketing margins and, assembler and retailer's margin is not less than wholesaler's. The fluctuation of the price of apple is high in year. The marketing problems of apples are several, first, complex marketing channels, secondly, the high percentage of market share by growing district assembler, thirdly, low rate of package and quality standardization, finally, concentration of shipment of apple because of the shortage of apple processing, storage and marketing facilities, of newly produced apples. In conclusion, to increase apple grower's income with the stabilization of supply and quality upgrade, the improvement measures of marketing system are as follows, first, government level's support in marketing facilities and mechanism, secondly, the increment of supply by grower's cooperatives, thirdly, the establishment of a serious of marketing system to increase the efficiency, fourthly, the establishment of cold-chain system and quality standardization of apple, finally, production of various kinds of apple processing goods.

• Journal of Family Resource Management and Policy Review
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• v.2 no.2
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• pp.135-145
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• 1998

The purpose of this study was to examine how much the cost of marriage ceremony has increased according to the economic growth. The relationship between marriage expenditures and other comparison variables such as per capital GNP, monthly income, consumer price index was particularly examined. All the money values were adjusted by consumer price index. Data from the Central Committee for Promotion of Saving were used in this study. The results of this study follow. First, nominal and actual total outlay of marriage ceremony has continuously increased. Total marriage ceremony cost was positively correlated with the housing price so that bridegroom’s outlay were greater than that of bride’s one since bridegroom was more likely to have the responsibility for the price of new couple’s house. Second, it was found that increased percentage rate of marriage ceremony cost was greater than that of national economic growth. The total marriage expenditure was about 10 times as much per capital income in 1990. Third, it was revealed that housing cost increased three times from 1990 to 1995, and marriage ceremony expense was accordingly increased twice during the same periods. Such trends tend to increase continuously. Last, the marriage cost percentage to monthly income called marriage expenditure share increased by 1990 and then decreased. Such a decreasing trend can be explained by the increased amount of income partly due to the higher wage rate compared to other conditions since 1990.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.2
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• pp.45-55
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• 2006

Air transportation industry becomes more competitive because that the restrictions on new access to market were eased and related enough for each airline to choose the freight rate and the route without rein. New competitors are pursuing convergence strategy which focuses on low freight rate as a niche strategy for increasing market share by stimulating low cost demand. This strategy is now spreading all over the world such places as Europe, Asia, Oceania and etc. As of December 1, 2004, hundreds of low cost carriers are participating actively in the market and finding their level as a new strategic group in the air transportation industry with expanding their market. In case of USA, however, many airlines, which had newly entered to the market, went into bankruptcy in the mid-1980s. People Express in USA established in 1980 is one of the examples of failure. In case of Japan, Hokkaido International Airline, a typical low cost carrier which established in 1997, filed for bankruptcy. This study is for examining the strategic implication closely through the study on management strategy and cases of failure of low cost carriers.

• Journal of the Korea Computer Graphics Society
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• v.2 no.2
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• pp.69-74
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• 1996

With the emergence of integrated global market and increased competition, many companies are interested in sharing the product model data. One of the solutions is to share the product model data over the computer network or the internet using a standard format. CAD/CAM, STEP, and internet technologies make it possible to share the product model data. This paper presents methods to visualize 3D STEP geometry data on the internet. To create an internet-based STEP model visualizer, the programming language Java and 3D scene description language VRML have been experimented. The STEP geometry data can be displayed either by Java applets of by a VRML browser. These visualization technologies are applied to a PDM development. Engineers who have a low cost web browser can share the expensive design information even at a remote site.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.5843-5849
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• 2015

This study analyzes the factor demand structure of sweet persimmon as a part of finding out cost cutting measures. Income and cost data from 2001~2013 Agricultural Income Survey are used for placing the translog cost function and estimating price elasticies and cross elasticities of labor, capital and intermediate input. The result shows that own price elasticities of all factors are small in absolute terms. Additionally the result indicates capital and intermediate input cannot be a substitution for labor, which is a top-line cost-share. It means that the demand for labor cconstitutionally can't be reduced in a short time. This implies that cost reduction should be done focusing on intermediate input, particularly on fertilizer and materials which have higher price elasticity of demand.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.4
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• pp.188-200
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• 2002

The WRR scheduling algorithm is widely used in ATM networks due to its simplicity and the low cost of hardware implementation. It guarantees minimum cell rate according to the weight of each queue. The fairness is a important factor for ABR service. That is, scheduling algorithm allocates network resources fairly to each VC. However, WRR algorithm shows worse performance on bursty traffic. Because it schedules input traffics according to predetermined weight, it can not satisfies fairness criteria, MCR plus equal share and Maximum of MCR or Max-Min share, defined by ATM Forum TM 4.1 specification. The Nabeshima et al algorithm is not adapt to network status rapidly because it is not compensate the weights of unused bandwidth to VCs and assign the unused bandwidth to VCs by RR method. In this paper, we propose a scheduling algorithm for satisfying the two fairness criteria, MCR plus equal share and Maximum of MCR or Max-Min share, among the six criteria defined by ATM Forum TM 4.1 specification. The WRR, Nabeshima et al, and the proposed scheduling algorithms are compared with respect to fairness and convergence time throughout experimental simulation. According to the simulation results, the proposed algorithm shows higher fairness and more rapid convergence than other algorithms.