• Journal of the Korean Statistical Society
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• v.32 no.2
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• pp.121-150
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• 2003

The National Health Interview Survey (NHIS) is one of the surveys used to assess the health status of the US population. One indicator of the nation's health is the total number of doctor visits made by the household members in the past year, There is a substantial nonresponse among the sampled households, and the main issue we address here is that the nonrespones mechanism should not be ignored because respondents and nonrespondents differ. It is standard practice to summarize the number of doctor visits by the binary variable of no doctor visit versus at least one doctor visit by a household for each of the fifty states and the District of Columbia. We consider a nonignorable nonresponse model that expresses uncertainty about ignorability through the ratio of odds of a household doctor visit among respondents to the odds of doctor visit among all households. This is a hierarchical model in which a nonignorable nonresponse model is centered on an ignorable nonresponse model. Another feature of this model is that it permits us to "borrow strength" across states as in small area estimation; this helps because some of the parameters are weakly identified. However, for simplicity we assume that the hyperparameters are fixed but unknown, and these hyperparameters are estimated by the EM algorithm; thereby making our method Bayes empirical Bayes. Our main result is that for some of the states the nonresponse mechanism can be considered non-ignorable, and that 95% credible intervals of the probability of a household doctor visit and the probability that a household responds shed important light on the NHIS.

• Korean Journal of Ecology and Environment
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• v.46 no.1
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• pp.10-17
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• 2013

History of Instream Flow Incremental Methodology (IFIM) Following the large reservoir and water development era of the mid-twentieth century in North America, resource agencies became concerned over the loss of many miles of riverine fish and wildlife resources in the arid western United States. Consequently, several western states began issuing rules for protecting existing stream resources from future depletions caused by accelerated water development. Many assessment methods appeared during the 1960's and early 1970's. These techniques were based on hydrologic analysis of the water supply and hydraulic considerations of critical stream channel segments, coupled with empirical observations of habitat quality and an understanding of riverine fish ecology. Following enactment of the National Environmental Policy Act (NEPA) of 1970, attention was shifted from minimum flows to the evaluation of alternative designs and operations of federally funded water projects. Methods capable of quantifying the effect of incremental changes in stream flow to evaluate a series of possible alternative development schemes were needed. This need led to the development of habitat versus discharge functions developed from life stage-specific relations for selected species, that is, fish passage, spawning, and rearing habitat versus flow for trout or salmon. During the late 1970's and early 1980's, an era of small hydropower development began. Hundreds of proposed hydropower sites in the Pacific Northwest and New England regions of the United States came under intensive examination by state and federal fishery management interests. During this transition period from evaluating large federal reservoirs to evaluating license applications for small hydropower, the Instream Flow Incremental Methodology (IFIM) was developed under the guidance of the U.S. Fish and Wildlife Service (USFWS).

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.1185-1194
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• 2020

This study aims to test Voluntary Disclosure, Quality of Financial Reporting and Information Asymmetry as Moderation Variables. The Voluntary Disclosure variable is calculated using the Index Disclosure. This research uses quantitative methods and uses partial least square with EViews data analysis. The research sample consisted of 225 manufacturing companies listed on the Indonesian stock exchange for the period 2016-2018. The results of the study state that voluntary disclosure has a positive and significant effect on the quality of financial reporting through asymmetric information. The relationship between voluntary disclosure and asymmetric information has a negative effect on the quality of financial reporting, states that the disclosure of voluntary reports to companies can prevent information asymmetry, as well as the relationship of voluntary disclosure to information asymmetry states that companies that make voluntary disclosure will increase the interest of investors and other stakeholders. The quality of financial reporting states that if there is information asymmetry, the quality of financial reporting will also decline. The low value of relevance will affect the level of large or small information gaps between management and investors. The quality of financial reporting with increased relevance means that asymmetric information will have a negative impact on financial reporting.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.63.2-63.2
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• 2015

Controlling and sensing spin states of magnetic molecules such as metallo-porphyrins at the single molecule level is essential for spintronic molecular device applications. Axial coordinations of diatomic molecules to metallo-porphyrins also play key roles in dynamic processes of biological functions such as blood pressure control and immune response. However, probing such reactions at the single molecule level to understand their physical mechanisms has been rarely performed. Here we present on our single molecule association and dissociation experiments between diatomic and metallo-porphyrin molecules on Au(111) describing its adsorption structures, spin states, and dissociation mechanisms. We observed bright ring shapes in NO adsorbed metallo-porphyrin compelxes and explained them by considering tilted binding and precession motion of NO. Before NO exposure, Co-porphryin showed a clear zero-bias peak in scanning tunneling spectroscopy, a signature of Kondo effect in STS, whereas after NO exposures it formed a molecular complex, NO-Co-porphyrin, that did not show any zero-bias feature implying that the Kondo effect was switched off by binding of NO. Under tunneling junctions of scanning tunneling microscope, both positive and negative energy pulses. From the observed power law relations between dissociation rate and tunneling current, we argue that the dissociations were inelastically induced with molecular orbital resonances. Our study shows that single molecule association and dissociation can be used to probe spin states and reaction mechanisms in a variety of axial coordination between small molecules and metallo-porphyrins.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.1
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• pp.43-47
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• 2013

In this work, we report extraction of the density-of-states (DOS) in polymer-based organic thin film transistors through the multi-frequency C-V spectroscopy. Extracted DOS is implemented into a TCAD simulator and obtained a consistent output curves with non-linear characteristics considering the contact resistance effect. We employed a Schottky contact model for the source and drain to fully reproduce a strong nonlinearity with proper physical mechanisms in the output characteristics even under a very small drain biases. For experimental verification of the model and extracted DOS, 2 different OTFTs (P3HT and PQT-12) are employed. By controlling the Schottky contact model parameters in the TCAD simulator, we accurately reproduced the nonlinearity in the output characteristics of OTFT.

• Smart Media Journal
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• v.5 no.1
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• pp.30-37
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• 2016

In recent decades, the study of human brain function has dramatically increased thanks to the advent of Functional Magnetic Resonance Imaging. This is a powerful tool which provides a deep view of the activities of the brain. From fMRI data, the neuroscientists analyze which parts of the brain have responsibility for a particular action and finding the common pattern representing each state involved in these tasks. This is one of the most challenges in neuroscience area because of noisy, sparsity of data as well as the differences of anatomical brain structure of each person. In this paper, we propose the use of appropriate discriminant methods, such as Fisher Discriminant Ratio and hypothesis testing, together with strong boosting ability of Adaboost classifier. We prove that discriminant methods are effective in classifying cognitive states. The experiment results show significant better accuracy than previous works. We also show that it is possible to train a successful classifier without prior anatomical knowledge and use only a small number of features.

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.820-826
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• 1996

The p2H dependence of the NMR chemical shifts of the proton signals of heme methyl groups and ionizable groups in the vicinity of the heme were investigated. The p2H titration of heme methyl signals in four macroscopic oxidation states by saturation tranfer method was performed in the range between p2H 5.2 and 9.0. While the p2H dependence of the heme methyl resonance in fully oxidized state was small, most resonances in the intermediate oxidation states showed certain shifts. Particularly, methyl resonances of heme 1 (sequential heme numbering) exhibited sharp p2H dependence in acidic range. β-CH2 of the propionate of hemes 1 and 4 were titrated in the range of p2H 4.5-9.0. Only the 6-propionate group of heme 1 was protonated in this p2H range and its titration curve was similar to those of methyl resonances of heme 1 in intermediate oxidation states. Analysis of the microscopic redox potentials showed that they change depending on p2H. The ionizable groups responsible for the p2H dependence of these potentials are 6-propionate of heme 1 in acidic range and His 67 in basic range.

• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.324-330
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• 1996

We examined the formal oxidation states of Pb and Cu in the Pb2CuO4 slab of Pb2Sr2ACu3O8(A=Y1-xCaxor Nd1-xSrx) and their possible changes by oxygen incorporation in the Cu layer of the slab by performing tight-binding band electronic structure calculations on the Pb2CuO4+δ slab. Our results show that the most likely oxidation state of Pb is +2 and that of Cu is +1 for the Pb2CuO4 slab prior to oxidation. With small δ values, the oxygen incorporation occurs by the formation of such chain fragments as in YBa2Cu3O7-y along the a+b axis. The four-coordinate Cu atoms in the chain fragments are in the +3 oxidation states. For values of δ larger than 0.5, however, an additional oxygen (Oad) goes to the site along the b axis to form short Pb-Oad distances oxidizing Pb2+ to Pb4+. This change in the Pb oxidation state leads to the suppression of superconductivity due to the decrease of holes in the CuO2 layer.

• Mycobiology
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• v.49 no.6
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• pp.551-558
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• 2021

The Federated States of Micronesia (FSM) is an island country in the western Pacific and is a known biodiversity hotspot. However, a relatively small number of fungi (236 species) have been reported till July 2021. Since fungi play major ecological roles in ecosystems, we investigated the fungal diversity of FSM from various sources over 2016 and 2017 and constructed a local fungal inventory, which also included the previously reported species. Fruiting bodies were collected from various host trees and fungal strains were isolated from marine and terrestrial environments. A total of 99 species, of which 78 were newly reported in the FSM, were identified at the species level using a combination of molecular and morphological approaches. Many fungal species were specific to the environment, host, or source. Upon construction of the fungal inventory, 314 species were confirmed to reside in the FSM. This inventory will serve as an important basis for monitoring fungal diversity and identifying novel biological resources in FSM.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.411-414
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• 2015

The purpose of this study is to conduct a comparative analysis between Korea and the United States of the supply process of unit modular housing at both the factory production phase and the transportation and lifting phase, as part of an attempt to invigorate the unit modular housing market in Korea. Unlike the practice in the United States, one of Korea's unique characteristics is that the floor is constructed with reinforced concrete and hot water heating system. To do this, the wet method in Korea is used that includes concrete placement, curing and constructing hot water floor heating system at the factory production phase, which results in a longer production time and also requires the lifting of heavier loads. In the United States, interior and exterior finishing works of modular housing are performed by different companies, and the distance between the unit module factory and the construction site is quite far. This kind of dualized production structure may cause confusion when it comes to schedule management, procurement management, and stock management. Moreover, problems caused by external environmental factors such as wind and rainfall were reported in the course of long-distance transportation. The results of this case comparison are expected to provide fundamental data that will reduce the amount of trial and error in the unit module production, transportation and lifting work in Korea, which has a comparatively small number of unit modular housing cases.