• Journal of Digital Convergence
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• v.16 no.12
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• pp.175-183
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• 2018

This study analyzes determinants of bond returns in terms of systematic risk versus idiosyncratic risk by examining relationship among those factors. First we examined the cross-sectional determinants of corporate bond returns with Korean bond market data from 2001 to 2014. This paper uses term factor and default factor for systematic risk, and duration factor and credit rating factor for idiosyncratic risk. The empirical result shows that systematic risk can explain cross-sectional differences of bond returns rather than idiosyncratic risk which is the same result in advanced markets(US or Europe). This result is different from the previous Korean studies which showed that idiosyncratic risk is more important than systematic risk in Korean bond market. The reason for the different result may be the longer sample period which includes the most recent period. It is insisted that Korean bond market is getting more synchronized with the advanced bond market. In conclusion, this empirical result implies that Korean bond portfolio managers should focus on systematic risk, which is contrary to current system in Korean asset management industry.

• Journal of the Korean Data and Information Science Society
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• v.27 no.3
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• pp.835-844
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• 2016

We develop the testing procedures about the homogeneity of the shape parameters of several inverse Gaussian distributions in our paper. We propose default Bayesian testing procedures for the shape parameters under the reference priors. The Bayes factor based on the proper priors gives the successful results for Bayesian hypothesis testing. For the case of the lack of information, the noninformative priors such as Jereys' prior or the reference prior can be used. Jereys' prior or the reference prior involves the undefined constants in the computation of the Bayes factors. Therefore under the reference priors, we develop the Bayesian testing procedures with the intrinsic Bayes factors and the fractional Bayes factor. Simulation study for the performance of the developed testing procedures is given, and an example for illustration is given.

• Journal of the Korean Data and Information Science Society
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• v.28 no.1
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• pp.217-225
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• 2017

This article deals with the problem of multiple hypothesis testing for the shape parameter in the generalized exponential distribution. We propose Bayesian hypothesis testing procedures for multiple hypotheses of the shape parameter with the noninformative prior. The Bayes factor with the noninformative prior is not well defined. The reason is that the most of the noninformative prior can be improper. Therefore we study the default Bayesian multiple hypothesis testing methods using the fractional and intrinsic Bayes factors with the reference priors. Simulation study is performed and an example is given.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.461-469
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• 2019

The aim of this study was to analyze the contribution of carcass traits (backfat thickness, eye muscle area, carcass weight and marbling score) and the season at slaughter to the price (auction and market) using squared semi-partial correlation. The season at slaughter (summer expressed as season_2, autumn as season_3, and winter as season_4) were added into the estimation as dummy variables, and spring was set as a default variable. In this study, the carcass grades of 22,298 Hanwoo steers slaughtered from 2012 to 2017 were used to performmultiple regression analysis. The rankings of the contribution of the carcass traits and the seasons at slaughter to the auction prices were in the order of marbling score (68.63%), season_4 (11.88%), backfat thickness (10.45%), eye muscle area (6.11%), season_3 (2.19%), season_2 (0.45%) and carcass weight (0.28%). (R-square of the regression = 0.4101). The rankings of the contribution to the total prices were in the order of carcass weight (51.74%), marbling score (32.12%), season_4 (6.04%), backfat thickness (5.54%), eye muscle area (3.22%), season_3 (1.14%), and season_2 (0.19%). (R-Square of the regression = 0.6486). As a result, season_3 and season_4 had a negative effect on the auction price and total price. Because of seasonal event such as Korean Thanksgiving Day and Korean New Year's Day on season_3 and season_4, much supply was needed to meet the high demand. Thus, the seasonal effect at slaughter could be another factor to be cosideredin when considering of slaughter or breeding.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.3
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• pp.115-119
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• 2018

Defining and measuring non-rigid or flexible parts has been controversial in industry for many years. There are two primary areas of controversy. The first is agreeing on what exactly a non-rigid part is. The second is agreeing on how to define and measure a non-rigid part. The subject of non-rigid parts is further complicated by the brief coverage it receives in the national and international standards. This leaves each company to improvise or create its own rules for non-rigid parts. There are some who believe that Geometrical Dimensioning and Tolerancing (GD&T) should not be used on non-rigid parts. This is not true. The ASME Y14.5M standard applies to rigid parts as a default condition. However, there is no definition given for a rigid part. The term rigid part has been used in industry for so long that it has gained a definition by its general use. When most people in industry say rigid part, they are referring to a part doesn't move (deform or flex) when a force (including gravity) is applied. How much force is relative based on the part characteristics. In reality, all parts will deform (or flex) if enough force is applied. Using this logic, all parts would be considered non-rigid. However, we all know that this is not how parts are treated in industry. Although GD&T defaults to rigid parts, it should also be used on non-rigid parts with a few special techniques. Actually 50~60% of all products designed contain parts or features on parts that are non-rigid. Therefore, we try to suggest the definitions of rigid and non-rigid parts and method to measure non-rigid parts.

• The Journal of Fisheries Business Administration
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• v.37 no.3 s.72
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• pp.45-63
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• 2006

A number of public loans with lower interests and other tax benefits have been provided for farmers and fishermen. However, much of those loans have been accumulated as non-performing. The result is that a large part of fisheries debts are now on the verge of default, Those loans, that fail to pay interests, keep rapidly growing like a time bomb. Now something has to be done before it burst. Firstly, the government must clean up the debts caused by government's mismanagement in the past. The past debt must be repaid or written off by the government since its guarantee was committed several times in guidelines regarding public loans. As such a measure, the government can greatly enlarge its capital contribution to the Credit Guarantee Fund for Farmers and Fishermen and Loss Guarantee fund for Policy Loan. It would greatly help to compensate local branches of fisheries cooperatives for their loss incurred from carrying public loans. In the past, the government used to roll over old debts of fishermen with new debts whenever maturity came. It ends up growing the size of non - performing loans. For this reason, it is not delay of the debt payment, but its write - off that fishery society needs a lot. Secondly, the loan authorities must lower overall risk in providing public loans for fishermen in the future. The whole process must be thoroughly reviewed and changed to provide and manage government loans. To facilitate this, fisheries cooperative must stop being just a public agent, rather take a bigger responsibility in selecting, and checking loan beneficiaries, and securing debt repayment. Incentives must be arranged properly enough to induce fisheries cooperatives to treat public loans just like their own business. Finally, the so - called 'special account of policy loan in fisheries industry' must be set up to enhance the transparency and to check the performance of public loans programs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.78-82
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• 2010

Vessel numbers and fuel consumption by South Korea's offshore and coastal fisheries have continuously declined since 2000. Using the 2006 Intergovernmental Panel on Climate Change Guidelines, $CO_2$ emissions by South Korea's fishery industry (fishing and aquaculture, excluding deep-sea fishing) were calculated by the default $ CO_2$ emission factor and fuel consumption by fuel type, Emission of $CO_2$ was estimated to be 3.22 million $tCO_2$/year in 2007 for fisheries (excluding deep-sea fishing); when including deep-sea fishing, the estimated value increased to 4.11 million $tCO_2$/year. Fuel consumption per tonne of fishery production was 498 L, and the amount of $CO_2$ emission per tonne of production was 1.62 $tCO_2$. To calculate $CO_2$ emission more exactly, we must develop a system to compile energy balance statistics and introduce life-cycle assessment for the fishery industry.

• Journal of the Korean Data and Information Science Society
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• v.21 no.4
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• pp.747-756
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• 2010

With the recent recession, studies on the economy are actively being conducted throughout the industry. Based on the Small Business data registered in the Credit Guarantee Fund, we estimated the survival probability in the context of the survival analysis. We also analyzed the survival time for the construction and the other industries which are distinguished depending on the types of business and assets in the Small Business. The survival probability was estimated by using the life-table and the difference between the survival probabilities for the different types of business was described via the method of the Log-rank test and the Wilcoxon test. We found that the small business with over one billion asset has the highest survival probability and that with less than 1000 million asset showed the similar survival probability. In terms of types of business Wholesale and Retail trade industry and Services were relatively high in the survival probability than Light, Heavy, and the construction industries. Especially the construction industry showed the lowest survival probability. Most of the Small Business tend to increase in the hazard rate over time.

• Korean Journal of Construction Engineering and Management
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• v.12 no.5
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• pp.137-145
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• 2011

BIM Data exchange using standard format can provide a user friendly and practical way of integrating the BIM tools in the life cycle of a building on the currently construction industry which is participated various stakeholder. It used IFC format to exchange the BIM data from Design software to energy analysis software. However, since we can not use the material name data in the library of an energy analysis directly, it is necessary to input the material property data for building energy analysis. In this paper, to matching the material named of name of DOE-2 default library, rhe extracted material names from BIM file are inferred by the ontology With this we can make the reliable input data of the engine by development a standard data and also increase the efficient of building energy analysis process. The methodology can enable to provide a direction of BIM-based information management system as a conceptual study of using ontology in the construction industry.

• The Korean Journal of Financial Management
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• v.25 no.3
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• pp.131-153
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• 2008

This paper calculates the Risk Index of Korean securities industry that summarizes the information contained in seventeen financial indicators that represent risk categories such as capital adequacy(C), asset quality(A), earnings(E), and liquidity(L) by using the NBER statistical methodology. For the validation of Risk Index, expected default frequency has been used, and the result has been proved to be positive. According to the compiled Risk Index, the level of risks of Korean securities industry has been decreasing from the second quarter of 2003 to the first quarter of 2006 by 22 percent. But the risk has been increasing during the periods from the first quarter of 2002 to the first quarter of 2003 and from the first quarter of 2006 to the last quarter of 2006.