• Korean Journal of Optics and Photonics
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• v.4 no.3
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• pp.294-300
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• 1993

Monolithic NOR and INVERTER active optical logic devices inte- grated with surface-emitting microlasers, heterojunction photo- transistors(HPT) in parallel and resistors in series are characterized. The differential quantum efficiency of the typical AlGaAs superlattice microlaser integrated in the active optical logic devices is 15%. Current gain of the HPT is 57, when emitter-collector voltage and input optical power are 4 V and $50{\mu}W$, respectively. $57{\mu}W$ of output power from the active optical logic device decreases to zero when $47{\mu}W$ of input optical power is incident on the HPT part of the active logic device.

• Journal of Environmental Impact Assessment
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• v.20 no.4
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• pp.565-574
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• 2011

This paper aims to design a policy-assessment tool liking the Environmental Impact Assessment(EIA) and the Cost Benefit Analysis (CBA). As a step towards the incorporation of environmental and economic considerations, the approach used herein takes the form of integrating quantitative information on environmental benefits and costs associated with implementing the project into the existing framework of the EIA. Our case study is an project appraisal of a solar energy plant. It is confirmed that the technique is operational, however, there are certain limitations for a complete assessment. The difficulty mainly originated from the omission of important information from each step of the valuation process. Alternatively stated, some environmental services are not identified, nor quantified, and nor monetized in the process. More case studies are warranted in the future along with elaboration in methodology of techniques. In addition, the construction of a database on environmental values will be required to accumulate reliable and systematized data. These are the necessary conditions to improving quality in application of techniques as well as providing comprehensive and balanced information to decision makers.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.1
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• pp.1-7
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• 2006

The present study was aimed to explore the role of sympathetic and parasympathetic nerves in the regulation of sodium transporters and water channels in the salivary gland. Rats were denervated of their sympathetic and parasympathetic nerves to the submandibular gland, and the glandular expression of sodium transporters and water channels was determined by Western blot analysis. The expression of either ${\alpha}1$ or ${\beta}1$ subunit of Na, K-ATPase was not significantly affected either by the sympathetic or by the parasympathetic denervation. The expression of subunits of epithelial sodium channels was significantly increased both in the denervated and contralateral glands either by the sympathetic or by the parasympathetic denervation. Neither the sympathetic nor the parasympathetic denervation significantly altered the expression of aquaporin-1 (AQP1). Nor was the expression of AQP4 affected significantly by the parasympathetic or the sympathetic denervation. On the contrary, the expression of AQP5 was significantly increased not only by the parasympathetic but also by the sympathetic denervation. These results suggest that sympathetic and parasympathetic nerves have tonic regulatory effects on the regulation of certain sodium transporters and AQP water channels in the salivary gland.

• YAKHAK HOEJI
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• v.46 no.3
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• pp.185-191
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• 2002

Alzheimer's disease (AD) involves neuronal degeneration with impaired cholinergic transmission, particularly in areas of the brain associated with learning and memory. Several cholinesterase inhibitors are widely prescribed to ameliorate the cognitive deficits in AD patients. In an attempt to examine if tacrine and donepezil, two well-known cholinesterase inhibitors, exhibit additional pharmacological actions in primary cultured rat cortical cells, we investigated the effects on neuronal injuries induced by glutamate or N-methyl-D-aspartate (NMDA), $\beta$-amyloid fragment ( $A_{{beta}25-35)}$), and various oxidative insults. Both tacrine and donepezil did not significantly inhibit the excitotoxic neuronal damage induced by glutamate. However, tacrine inhibited the toxicity induced by NMDA in a concentration-dependent fashion. In addition, tacrine significantly inhibited the $A_{{beta}25-35)}$-induced neuronal injury at the concentration of 50 $\mu$M. In contrast, donepezil did not reduce the NMDA- nor $A_{{beta}25-35)}$-induced neuronal injury. Tacrine and donepezil had no effects on oxidative neuronal injuries in cultures nor on lipid peroxidation in vitro. These results suggest that, in addition to its anticholinesterase activity, the neuroprotective effects by tacrine against the NMDA- and $A_{{beta}25-35)$-induced toxicity may be beneficial for the treatment of AD. In contrast, the potent and selective inhibition of central acetylcholinesterase appears to be the major action mechanism of donepezil.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.747-757
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• 2020

This study investigates the impact of bank regulation and supervision on the efficiency of banking sectors on 108 Islamic banks from 26 countries offering Islamic banking and finance products and services. The technical efficiencies of individual Islamic banks have been analyzed using the data envelopment analysis method (DEA). The ordinary least square estimation method is employed to examine the impact of country supervision and regulation on the technical efficiency of Islamic banks. The empirical findings suggest that supervisory power, activity restrictions and private monitoring positively influence the efficiency of Islamic banks. The study revealed that Islamic banks that are operating in Middle East and North Africa (MENA) and middle-income countries are more technically efficient given the less stringent rules on capital requirement and we found that there is statistically significant evidence that higher capital requirements are negatively associated with the efficiency of Islamic banks. The empirical findings of this study are expected to help policy-makers and government officials to better understand how their decisions affect the performance.

• ETRI Journal
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• v.32 no.3
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• pp.395-405
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• 2010

A novel multiclassifier system (MCS) strategy is proposed and applied to a text-dependent speaker verification task. The presented scheme optimizes the linear combination of classifiers on an on-line basis. In contrast to ordinary MCS approaches, neither a priori distributions nor pre-tuned parameters are required. The idea is to improve the most accurate classifier by making use of the incremental information provided by the second classifier. The on-line multiclassifier optimization approach is applicable to any pattern recognition problem. The proposed method needs neither a priori distributions nor pre-estimated weights, and does not make use of any consideration about training/testing matching conditions. Results with Yoho database show that the presented approach can lead to reductions in equal error rate as high as 28%, when compared with the most accurate classifier, and 11% against a standard method for the optimization of linear combination of classifiers.

• Korean Journal of Plant Resources
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• v.7 no.1
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• pp.29-34
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• 1994

Two new 1,2-seco-1-nor-6((5 $\mapsto$ 10)abeo-picrasan-2,5-olideskeleton quassinoids, eurylactones A [1] and B [2], and two new $C_{19}$ skeleton quassinoids 3 and 4 were isolated from Eurycoma longifolia together with two known $C_{18}$ quassinoids 5 and 6. Their sttuctures were established by the spectral evidence.Many quassinoids have already been isolated (1-3) from the roots, wood, and leaves of Eurycoma longiolia Jack (Simaroubaceae) and have been used as a folk medicine insoutheast Asia. As part of a series of studies, we have further undertaken the chemicalinvestigation of the n-BuOH-soluble fraction of the MeOH extract and isolated two new1,2-seco-1-nor-6(5 $\mapsto$ 10)abeo-picrasane skeleton quassinoids 1 and 2, which have beenknown only in shinjulactone B (4,5) and yadanfiolide (6), two new $C_{19}$-type quasslnolds3 and 4, and two known C18-type quassinoids 5 and 6. In this paper, the structureelucidation and biosenetic relation of these compounds are described.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.4
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• pp.25-37
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• 2009

This Study constructs a dashboard system to synthetically and systematically monitor national R&D information based on data warehouse. Managing the national R&D statistics and trend is important since it provides data for policies and decision making for national R&D. Many agencies related to national R&D information collect the basic R&D statistic data which provides the basis of logical decision making and R&D policies. The data has not well been used. The data has not been consistently collected nor managed. The raw data has not been organized nor processed to meet various demands. The needs has been arisen for a consistent national R&D monitoring system to increase the relevance, accessibility and efficiency of data for various users. This study selects 25 key indicators based on the user requirements and designs data warehouse for supporting the indicators using star schema. The dashboard system is developed in this study provides the infrastructure of monitoring national R&D information and analytic environment of supporting statistical analysis and time-series data analysis.

• Journal of the Korean Home Economics Association
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• v.47 no.8
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• pp.13-24
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• 2009

This study investigated college students' time management behavior and time satisfaction according to the use of the time-matrix. Data were collected from 400 college students in Seoul by a self-administered questionnaire. Collected data were subjected to descriptive and comparative statistical analyses using the software SPSS(version 12.0). The conclusions of this study were as follows; 1. The use of time-matrix was categorized into 4 task groups: (1) not urgent but important, (2) urgent but notimportant, (3) neither urgent nor important, (4) urgent and important. 2. Time-management-behavior of planning was categorized into 3 components: standard setting, reality overlapping and implementing into 3 components(i.e., checking, adjusting, facilitating condition). 3. In all domains except overlapping, 'not urgent but importance' was the most popular managerial behavior. 4. However, 'neither urgent nor important' was voted the most popular in terms of managerial satisfaction. This study provides useful knowledge on managerial time-use categorization. Furthermore also contributes towards the knowledge base of time-managerial behaviors and dispels stereotypical-thinking that only bing busy all the time using is an indication of good time management behavior. Finally, this study advocates use of the time-matrix to achieve efficient time management.

• The Journal of Korean Physical Therapy
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• v.2 no.1
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• pp.47-63
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• 1990

The purpose of this study was to determined the effect of low-frequency electrical stimulation on the denervated gastrocnemius muscles of the albino rats, Sprague-Dawley. Fifteen Sprague-Dawley adult male albino rats were divided into non-treated (normal) group, denervated (control) group, denervated and electrical stimulated (experiments). The gastrocnemius muscles of the right leg were submaximally stimulated with 30 Hz electrical stimulation. After 4-week period, the animals were sacrificed, and muscle were removed, fixed by immersion, and processed for light and electron microscopy. The numbers of Ag-NOR increased significantly (p<0.001), but significant reductions of girth(p<0.01), wet muscle weight (p<0.001), high glycogen content fiber (p<0.01), and mitochondrial number (p<0.05) were found in denervated control group. In comparison with control group, significant increase of right leg girth (p<0.05), wet muscle weight (p<0.001), high glycogen content fiber (p<0.05), numbers of Ag-NOR(p<0.001), number of mitochondria (p<0.01), mitochondrial volume found in electrical stimulated experimental group. The results suggest that the electrical stimulation of the muscle partially prevented the denervated atrophy in the rat gastrocnemius muscles.