• Journal of the Korean Statistical Society
• /
• v.31 no.1
• /
• pp.63-75
• /
• 2002

Most attempts at Bayesian analysis of neural networks involve hierarchical modeling. We believe that similar results can be obtained with simpler models that require less computational effort, as long as appropriate restrictions are placed on parameters in order to ensure propriety of posterior distributions. In particular, we adopt a model first introduced by Lee (1999) that utilizes an improper prior for all parameters. Straightforward Gibbs sampling is possible, with the exception of the bias parameters, which are embedded in nonlinear sigmoidal functions. In addition to the problems posed by nonlinearity, direct sampling from the posterior distributions of the bias parameters is compounded due to the duplication of hidden nodes, which is a source of multimodality. In this regard, we focus on sampling from the marginal posterior distribution of the bias parameters with Markov chain Monte Carlo methods that combine traditional Metropolis sampling with a slice sampler described by Neal (1997, 2001). The methods are illustrated with data examples that are largely confined to the analysis of nonparametric regression models.

• Nuclear Engineering and Technology
• /
• v.52 no.6
• /
• pp.1334-1339
• /
• 2020

This paper presents an empirical and comprehensive forecasting analysis of the uranium price. Prices are generally difficult to forecast, and the uranium price is not an exception because it is affected by many external factors, apart from imbalances between demand and supply. Therefore, a systematic analysis of multiple forecasting methods and combinations of them along repeated forecast origins is a way of discerning which method is most suitable. Results suggest that i) some sophisticated methods do not improve upon the Naïve's (horizontal) forecast and ii) Unobserved Components methods are the most powerful, although the gain in accuracy is not big. These two facts together imply that uranium prices are undoubtedly subject to many uncertainties.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2003.11a
• /
• pp.669-675
• /
• 2003

This paper examines structural breaks and asymmetries of prices of four domestic petroleum products, i.e., gasoline, kerosene, diesel, and bunker-C, following the changes in the pricing policies pertaining to petroleum products in Korea from the government-controlled pricing system to the market pricing system. We use the monthly wholesale market price data for the sample period between July 1988 and December 2001. Using the four methods: the Chow test, the CUSUM/CUSUMQ tests, the Bayesian approach and the Dufour test, the structural behaviors of the petroleum product prices are examined. We found that structural change occurred in all petroleum products, with the exception of Kerosene, at the point of pricing policy change from government-controlled to the spot-price related pricing system. We, also conducted asymmetric analysis using the Borenstein, Cameron, and Gilbert (1997)'s model and found evidences of price asymmetry for all four product types, but in different pattern for each product.

• Journal of Microbiology and Biotechnology
• /
• v.9 no.5
• /
• pp.691-693
• /
• 1999

Resveratrol (trans-3,5,4'-trihydroxystilbene), a phenolic substance present in both grapes and wines, has been reported to have certain pharmacological effects. Using an ethylacetate-phase extraction followed by a high performance liquid chromatographic analysis, the concentration of trans-resveratrol was measured in 9 red wines commercially available in Korea, including the Korean red wine (Noul). Noul red wine with a 1998 vintage had a trans-resveratrol concentration of 3.3 ㎎/l, which was rather higher than the concentrations found in other wines (0.19-2.45 ㎎/l) with the exception of the French wine, J. P. Chenet (3.39 ㎎/l). In addition, the grapes of Vitis labrusca cv. Sheridan cultivated in the Kyungsan area showed a trans-resveratrol content of 6.4 ㎎/㎏.

• East Asian Economic Review
• /
• v.19 no.4
• /
• pp.357-379
• /
• 2015

We investigate interconnectedness and the contagion effect of default risk in Asian sovereign CDS markets since the global financial crisis. Using dynamic conditional correlation analysis, we find that there are significant co-movements in Asian sovereign CDS markets; that such co-movements tend to be larger between developing countries than between developed and developing countries; and that in the co-movements intra-regional nature is stronger than inter-regional nature. With the Spillover Index model, we measure contagion probabilities of sovereign default risk in CDS markets of seven Asian countries and find evidence of contagion effects among six of them; Japan is the exception. In addition, we find that these six countries are affected more by cross-market spillovers than by their own-market spillovers. Furthermore, a rolling-sample analysis reveals that contagion in the Asian sovereign CDS markets expands during episodes of extreme economic and financial distress, such as the Lehman Brothers bankruptcy, the European financial crisis, and the US-credit downgrade.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.5
• /
• pp.993-999
• /
• 1998

Methanol extract of roots of Amblytropis pauciflora Kitagawa showed the antimicrobial activity to three test strains. Antimicrobial spectra of various extracts of Amblytropis pauciflora Kitagawa were tested against 24 strains of bacteria and fungi. The crude methanol extract inhibited the growth of 12 strains of bacteria and Asp. fumigatus with the exception of yeasts. The properties of the antimicrobial substance were very stable under heat(at 12$0^{\circ}C$), acid(pH 3.0) and alkali(pH 11.0) treatment. Only the root harvested in spring showed the antimicrobial activity. Among the components extracted by butanol, ginseng saponin Rg1 and various saponin-like materials were detected by TLC analysis using a plate of silica gel 60F254. The antimicrobial compound was purified by methanol extraction, activated charcoal column chromatography, Sep-pak(C18) pretreatment and reverse phase HPLC. The purified compound was detected at 13.520 min as a single peak(about 98% purity) through the HPLC analysis.

• SUVANNABHUMI
• /
• v.14 no.2
• /
• pp.89-116
• /
• 2022

During the Covid-19 pandemic's first term of April-June 2020, the general public throughout Indonesia became familiar with the slang term "local lockdown." This term emerged in response to disorderly implementation of the half-hearted government policy called Pembatasan Sosial Berskala Besar (PSBB). In villages around the country, people started to build portals to restrict "strangers" or "outsiders" from entering their village areas. These portals were also meant to publicly signal the villagers' fear of the spread of the virus. This paper will discuss two things: first, how fear was produced, using frameworks drawn from Giorgio Agamben's notable works State of Exception and Homo Sacer, and how governance reproduces it; and second, how people come to accept the state of emergency and then publicly express their acceptance of the situation. Critical discourse analysis is applied to read government policy and its reception. The research took place at Rempoah, Kedungmalang, and Pabuwaran villages in Banyumas, the southern regency of Central Java, Indonesia. The villagers' responses to the government's policy are visually represented through written warning signs.

• The Journal of Economics, Marketing and Management
• /
• v.6 no.2
• /
• pp.29-33
• /
• 2018

Purpose - This study aims to offer the suggestions for the researches and policies that could be used as important data to effectuate future FTA. The objective of this study is to suggest a direction of Korea that can form a new logistics hub in Northeast Asia. Research design, data, and methodology - This study was conducted in parallel with literature review and empirical studies for the analysis. 180 valid samples were collected from Korean consumers', and qualitative analysis was employed on the satisfaction level of imported goods welfare of Korean consumers. Results - It is expected that Korea and China would experience increased opportunity factors in this area with the growth of economic sphere in Northeast Asian. If existing problems are solved by utilizing regional environment efficiently together, the hub function of Northeast Asia logistics will be advanced. Conclusions - Korea is introducing and operating special economic zones that provide the exception and support for foreign investment. Therefore, it is necessary to monitor the prices of imported goods, so that the exporters can adjust the prices and obtain the unjust profit equivalent to the tariff reduction by grasping the overseas market trends of the imported product prices.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.07a
• /
• pp.403-404
• /
• 2022

초보 학습자의 프로그래밍 과정에서 발생하는 오류는 다양하며 학습자가 스스로 오류 분석을 하거나 수정은 어렵다. 이에 본 논문은 블록 프로그래밍 기반의 교육 플랫폼인 에듀비를 활용하여 오류 분석 방안을 제시하고자 한다. 분석 방안의 활용 가능성을 확인하기 위해 실제 학습자들이 분류모델을 생성하고 평가하는 과제를 수행하였고 학습자들이 과제를 수행하면서 발생한 오류사례에 대해 분석하였다.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.7
• /
• pp.1029-1036
• /
• 2016

This study investigated the degree to which instrumental measurements explain the variation in pork loin tenderness as assessed by the sensory evaluation of trained panelists. Warner-Bratzler shear force (WBS) had a significant relationship with the sensory tenderness variables, such as softness, initial tenderness, chewiness, and rate of breakdown. In a regression analysis, WBS could account variations in these sensory variables, though only to a limited proportion of variation. On the other hand, three parameters from texture profile analysis (TPA)-hardness, gumminess, and chewiness-were significantly correlated with all sensory evaluation variables. In particular, from the result of stepwise regression analysis, TPA hardness alone explained over 15% of variation in all sensory evaluation variables, with the exception of perceptible residue. Based on these results, TPA analysis was found to be better than WBS measurement, with the TPA parameter hardness likely to prove particularly useful, in terms of predicting pork loin tenderness as rated by trained panelists. However, sensory evaluation should be conducted to investigate practical pork tenderness perceived by consumer, because both instrumental measurements could explain only a small portion (less than 20%) of the variability in sensory evaluation.