• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.880-884
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• 2001

Rumen microbiology research has undergone several evolutionary steps: the isolation and nutritional characterization of readily cultivated microbes; followed by the cloning and sequence analysis of individual genes relevant to key digestive processes; through to the use of small subunit ribosomal RNA (SSU rRNA) sequences for a cultivation-independent examination of microbial diversity. Our knowledge of rumen microbiology has expanded as a result, but the translation of this information into productive alterations of ruminal function has been rather limited. For instance, the cloning and characterization of cellulase genes in Escherichia coli has yielded some valuable information about this complex enzyme system in ruminal bacteria. SSU rRNA analyses have also confirmed that a considerable amount of the microbial diversity in the rumen is not represented in existing culture collections. However, we still have little idea of whether the key, and potentially rate-limiting, gene products and (or) microbial interactions have been identified. Technologies allowing high throughput nucleotide and protein sequence analysis have led to the emergence of two new fields of investigation, genomics and proteomics. Both disciplines can be further subdivided into functional and comparative lines of investigation. The massive accumulation of microbial DNA and protein sequence data, including complete genome sequences, is revolutionizing the way we examine microbial physiology and diversity. We describe here some examples of our use of genomics- and proteomics-based methods, to analyze the cellulase system of Ruminococcus flavefaciens FD-1 and explore the genome of Ruminococcus albus 8. At Illinois, we are using bacterial artificial chromosome (BAC) vectors to create libraries containing large (>75 kbases), contiguous segments of DNA from R. flavefaciens FD-1. Considering that every bacterium is not a candidate for whole genome sequencing, BAC libraries offer an attractive, alternative method to perform physical and functional analyses of a bacterium's genome. Our first plan is to use these BAC clones to determine whether or not cellulases and accessory genes in R. flavefaciens exist in clusters of orthologous genes (COGs). Proteomics is also being used to complement the BAC library/DNA sequencing approach. Proteins differentially expressed in response to carbon source are being identified by 2-D SDS-PAGE, followed by in-gel-digests and peptide mass mapping by MALDI-TOF Mass Spectrometry, as well as peptide sequencing by Edman degradation. At Ohio State, we have used a combination of functional proteomics, mutational analysis and differential display RT-PCR to obtain evidence suggesting that in addition to a cellulosome-like mechanism, R. albus 8 possesses other mechanisms for adhesion to plant surfaces. Genome walking on either side of these differentially expressed transcripts has also resulted in two interesting observations: i) a relatively large number of genes with no matches in the current databases and; ii) the identification of genes with a high level of sequence identity to those identified, until now, in the archaebacteria. Genomics and proteomics will also accelerate our understanding of microbial interactions, and allow a greater degree of in situ analyses in the future. The challenge is to utilize genomics and proteomics to improve our fundamental understanding of microbial physiology, diversity and ecology, and overcome constraints to ruminal function.

• The Journal of the Korea Contents Association
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• v.17 no.2
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• pp.13-25
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• 2017

This study aims to analyze the impacts on self-regulated learning (SRL) and problem-solving (PS) competencies rather than learning achievement through the use of digital textbooks in the SMART learning environment. To achieve the objective, $3^{rd}$ and $4^{th}$ grade elementary and $1^{st}$ year middle school students were selected from 29 schools where the digital textbooks were utilized in the subjects of science in pilot schools in 2014. In this, One-Group Pretest-Posttest Designs were applied as a research method to analyze SRL and PS competencies. Additionally, the effect size of Cohen's d was presented in order to display the practical significance. The results showed the positive impacts on SRL and PS competencies, in spite of a small effect size of about 0.2 through the use of digital textbooks. ANCOVA was conducted to determine the difference in the impacts according to demographic variables. The results demonstrated that the difference in the impacts on both SRL and PS were statistically significant according to the grade and level. For SRL, both the elementary grade 4 and middle school students showed more significant differences than elementary grade 3. Moreover, for PS, the elementary grade 4 students showed the most significant difference.

• Korean Journal of Optics and Photonics
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• v.19 no.2
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• pp.150-158
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• 2008

The exact transmission coefficients at the interface between a uniaxial anisotropic medium and an isotropic medium at? oblique incidence are derived by applying the extended Jones matrix method. When the birefringence of the uniaxial anisotropic medium is small ($|n_e-n_o|\;{\ll}\;n_o,\;n_e$), the exact transmission coefficients are compared with those by the conventional extended Jones matrix method by Yeh et al. They showed an excellent agreement with each other. In addition, using the exact transmission coefficients, we calculated the polarization characteristics of a light through a uniaxial medium to an incident light with arbitrary polarization state at? oblique incidence. We compared the transmittances of an unpolarized light through a pair of crossed o-type polarizers by two different methods and calculated the transmittance as the variation of the optical constants of the polarizers to evaluate of the extinction ratio. The polarization analysis method using the exact transmission coefficients can be applied to polarization characteristics of a light through a uniaxial medium with large birefringence as well as to liquid crystals and to optical anisotropic material.

• 전자공학회논문지 IE
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• v.46 no.3
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• pp.6-11
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• 2009

In this paper, manufactured composite nanofiber by electrospinning that make spinning solvent according to weight of PAN/PVdF. PVdF content of composite nanofiber decreases, diameter of fiber decreased. Result that measure contact angle to confirm hydrophile property of PAN/PVdF composite nanofiber, PVdF content increases, could confirm that contact angle with water increases. After leave filter measurement sample for 25 hours in temperature of $40^{\circ}C$, humidity of 85%, result PAN/PVdF composite nanofiber that estimate efficiency could confirm that display performance of HEPA more than 99.95% and ULPA more than 99.999%. And fiber diameter is small, could confirm that filter performance increases. Tensile strength of bulk of PAN/PVdF composite nanofiber was 5-8MPa, expansion 100-300%. And strength and expansion could know that increase according as PVdF's content increases. Tensile strength was 3-8MPa degree after annealing PAN/PVdF composite nanofiber during 2 hours in 120t. Tensile strength was no change almost by annealing, and expansion could know that decrease.

• Progress in Medical Physics
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• v.22 no.3
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• pp.155-162
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• 2011

The analog image based system consisted of a simulator and medical linear accelerator (LINAC) for radiotherapy was upgraded to digital medical image based system by exchanging the X-ray film with Computed Radiography (CR). With minimum equipments shift and similar treatment process, it was possible that the new digital image system was adapted by the users in short time. The film cassette and the film developer device were substituted with a CR cassette and a CR Reader, where the ViewBox was replaced with a small size PC and a monitor. The viewer software suitable for radiotherapy was developed to maximize the benefit of digital image, and as the result the convenience and the effectiveness was improved. It has two windows to display two different images in the same time and equipped various search capability, contouring, window leveling, image resizing, translation, rotation and registration functions. In order to avoid any discontinuance of the treatment while the transition to digital image, the film and the CR was used together for 1 week, and then the film developer was removed. Since then the CR System has been operated stably for 2 months, and the various requests from users have been reflected to improve the system.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.3
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• pp.408-422
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• 2013

This paper builds on recent scholarly endeavours to establish a body of knowledge on Varieties of Asian Capitalism/Asian Business Systems. The forthcoming Oxford handbook of Asian business systems systematically compares institutional capitalist arrangements across Asia including Laos, yet there is no chapter on Cambodia. The objective of this paper is to compare the Lao and Cambodian varieties of Asian capitalism, with special reference to the role of the state and the economic geography of both countries. Accordingly, it seeks answers to the questions as to how territory has become a key arena for re-organising economic power and how the Lao and Cambodian state themselves are being transformed through state capitalism and the Beijing-Seoul-Tokyo Consensus. A comparative analysis reveals a difference between state-coordinated frontier capitalism in Laos versus patrimonial oligarchy in Cambodia. Interdependencies between the market and the state in Laos display the state as active and interventionist. In some provinces the central government leaves decision making to provincial elites contributing to the emergence of other distinctive regional varieties of capitalism. The rising spatially less selective oligarchs in Cambodia focus relatively more on markets, but are certainly not seeking free markets with equal entry opportunities. The findings offer interesting possibilities for further research on the spaces of Asian capitalism, both from an empirical and theoretical perspective. More work should be done to accommodate the role of small and medium enterprises and theories need to better integrate oligarchic, personal and familial capitalism. Finally, comparative corridor studies in Laos could lead to better insights into the nature of regional varieties of capitalism.

• Korean Journal of Cognitive Science
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• v.24 no.4
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• pp.365-391
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• 2013

Negative repetition effect (NRE) refers to the phenomenon that the accuracy of report is impaired when a target was flanked by the same distractor than when by alternative distractor. To probe the nature of NRE, this study introduced attention window(s) indicating the positions where a target might be presented, and non-attention window(s) where a target could not be presented. Attention windows are supposed to help participants detect targets readily. Two among three positions are indicated by attention windows in Exp. 1, and a single large attention window encompassing central two positions among four positions was used in Exp. 2, and either large or small attention window was used depending on the number of target candidates in Exp. 3. In the result of three experiments, NREs were consistently observed when both positions of a target and a distractor were indicated by previous attention windows. However, NREs (including its tendency) and its opposite, PREs were observed when a distractor was presented in the non-attention position, depending on its distance from the target and the size of attention window. It seems that this pattern of repetition effects is hard to be explained by repetition blindness hypothesis (Kanwisher, 1991), positional uncertainty hypothesis (Keren & Boer, 1985), and inhibitory attention capture hypothesis (Kwak et al., 1993). Instead it was proposed that shifting of spatial attention should be considered accordingly with the structure of stimulus display. The promising role of this task was discussed in studying the relation of attention and perception.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.183-183
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• 2014

Recently, multiferroic materials gain much attention due to their fascinating fundamental physical properties. These materials offer wide range of potential applications such as data storage, spintronic devices and sensors, where both electronic and magnetic polarizations can be coupled. Among single-phase multiferroic materials, $BiFeO_3$ is typical because of the room-temperature magnetoelectric coupling in view of long-range magnetic- and ferroelectric-ordering temperatures. However, $BiFeO_3$ is well known to have large leakage current and small spontaneous polarization due to the existence of oxygen vacancies and other defects. Furthermore the magnetic moment of pure $BiFeO_3$ is very weak owing to its antiferromagnetic nature. Recently, various attempts have been performed to improve the multiferroic properties of $BiFeO_3$ through the co-doping at the A and the B sites, by making use of the fact that the intrinsic polarization and magnetization are associated with the lone pair of $Bi^{3+}$ ions at the A sites and the partially-filled 3d orbitals of $Fe^{3+}$ ions at the B sites, respectively. In this study, $BiFeO_3$, $Bi_{0.9}Ho_{0.1}FeO_3$, $BiFe_{0.97}Ni_{0.03}O_3$ and $Bi_{0.9}Ho_{0.1}Fe_{0.97}Ni_{0.03}O_3$ bulk compounds were prepared by solid-state reaction and rapid sintering. High-purity $Bi_2O_3$, $Ho_2O_3$, $Fe_2O_3$ and $NiO_2$ powders with the stoichiometric proportions were mixed, and calcined at $500^{\circ}C$ for 24 h to produce the samples. The samples were immediately put into an oven, which was heated up to $800^{\circ}C$ and sintered in air for 1 h. The crystalline structure of samples was investigated at room temperature by using a Rigaku Miniflex powder diffractometer. The field-dependent and temperature-dependent magnetization measurements were performed with a vibrating-sample magnetometer and superconducting quantum-interference device.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.123-128
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• 2016

The study was conducted to confirm the analgesic effects of the Carbenoxolone(CBX)and P2X receptor antagonist(iso-PPADS), which separates the gap junction in the facial neuropathic pain model. The experiment used white male Sprague-Dawley rats (240~280g). The second left molars on the lower jaw was extracted to induce facial neuropathic pain, and small dental implants were implanted to induce damage to the inferior alveolar nerve. When CBX was injected twice daily to the abdominal cavity, a significant analgesic effect at 5ug/kg was observed(p<0.05). In addition, when iso-PPADS was injected twice daily into the abdominal cavity, a significant analgesic reaction was observed at $25{\mu}g/kg$(p<0.05). When the two drugs were injected together at a low concentration, in which they did not display an effect, they displayed a significant analgesic reaction at CBX 1ug/kg and iso-PPADS 2.5ug/kg(p<0.05). When a gap injunction block using a low concentration of CBX and a low concentration P2X receptor antagonist was injected together, the pain suppressing effect was observed against the orofacial neuropathic pain mechanism. These results make it possible to determine that the gap junction block using CBX and the injection of the P2X receptor antagonist plays an important role in the pain management of the facial region.

• Atmosphere
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• v.16 no.3
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• pp.247-257
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• 2006

The Yeong-dong heavy snowfall forecast supporting system has been developed during the last several years. In order to construct the conceptual model, we have examined the characteristics of heavy snowfalls in the Yeong-dong region classified into three precipitation patterns. This system is divided into two parts: forecast and observation. The main purpose of the forecast part is to produce value-added data and to display the geography based features reprocessing the numerical model results associated with a heavy snowfall. The forecast part consists of four submenus: synoptic fields, regional fields, precipitation and snowfall, and verification. Each offers guidance tips and data related with the prediction of heavy snowfalls, which helps weather forecasters understand better their meteorological conditions. The observation portion shows data of wind profiler and snow monitoring for application to nowcasting. The heavy snowfall forecast supporting system was applied and tested to the heavy snowfall event on 28 February 2006. In the beginning stage, this event showed the characteristics of warm precipitation pattern in the wind and surface pressure fields. However, we expected later on the weak warm precipitation pattern because the center of low pressure passing through the Straits of Korea was becoming weak. It was appeared that Gangwon Short Range Prediction System simulated a small amount of precipitation in the Yeong-dong region and this result generally agrees with the observations.