• Informatization Policy
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• v.25 no.2
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• pp.46-66
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• 2018

This research explores the factors affecting infusion of public administrative information systems(IS) and analyzes its impact on work performance. For this purpose, the factors affecting the infusion of IS are classified into voluntary and involuntary motivations based on the self-determination theory that explains individual motivations. As factors for voluntary motivation, performance expectancy, personal innovativeness, and organizational citizenship behavior are proposed, while government influence, competitor influence, and the top-level management influence are proposed as factors for involuntary motivation. The analysis shows the voluntary motivation factors-performance expectancy, personal innovativeness, and organizational citizenship behavior-do affect infusion of IS, whereas the involuntary motivation factors-government influence, competitor influence, and the top-level management influence-have no statistically significant impact on the infusion of IS. The relationship between infusion of IS and work performance is found significant. While individuals are unable to decide on the adoption of IS in an involuntary environment such as in the case of using the public administrative IS, the results show that the factors related to individual autonomy have an important role in extended, active usage of IS beyond the mandatory level.

• Nuclear Engineering and Technology
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• v.25 no.1
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• pp.125-135
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• 1993

The safe and efficient operation of nuclear plants is recognized to be accomplished through the application of plant automation using digital technology, which is one of main targets of the next generation nuclear plants. For plant level automation, it is first required that each major subsystem be digitalized, and the steam generator water level control system is discussed in this study. The transfer functions between inputs and the level are derived by employing the thermal hydraulic model of the steam generator and are applied to the analysis of the current three-element control system. Since the control scheme in this study includes the steam generator itself as a process plant, the system order is high and the numerical instability arises in digitalizing. Together with this, the unreliability of the feedwater feedback signal at low power level leads to the proposal of a two-element control system with a proper digital controller. The digital PI controller developed for this system has the initial power adaptive gain and integration time constant. And it makes the overall system response satisfy the stability and other necessary control specifications simultaneously. Since the two-element control system using this controller depends on the initial power only, it is simple to define and it shows a similar level response behavior to that of its corresponding analog system.

• The Journal of the Petrological Society of Korea
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• v.26 no.2
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• pp.99-112
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• 2017

Geoheritage is designated to preserve geodiversity of geological and geomorphological cases. Geotourism is an extensive activity that aims at the understanding of geology and earth's history for the geoheritage and for developing regions through preserving the geodiveristy of geoheritage. Igidae-Oryukdo is geosite of Busan National Geopark and its visitors are expected to grow rapidly. Accordingly, for the effective use of the geosites, The development and application of geotourism is required. This study suggests that tuffacious sedimentary rocks, hornblende megacrysts-bearing dike, copper mine, marine potholes should designated as the central points for advanced learning stage; volcanic breccia, sea caves, sea cliffs, wavecut platform, tor and islands as the central points for basic learning stage. Based on this central points, this study established concepts for getourism in this study area at basic and expert level for individual and family tourists, and also small or large groups such as school students.

• Journal of the Korea Society for Simulation
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• v.20 no.3
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• pp.69-78
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• 2011

A large-scale sensor network usually operates in open and unattended environments, hence individual sensor node is vulnerable to various attacks. Therefore, malicious attackers can physically capture sensor nodes and inject false reports into the network easily through compromised nodes. These false reports are forwarded to the base station. The false report injection attack causes not only false alarms, but also the depletion of the restricted energy resources in a battery powered network. The statistical en-route filtering (SEF) mechanism was proposed to detect and drop false reports en route. In SEF, the choice of routing paths largely affect the energy consumption rate and the detecting power of the false report. To sustain the secure routing path, when and how to execute the path re-selection is greatly need by reason of the frequent network topology change and the nodes's limitations. In this paper, the regional path re-selection period determination method is proposed for efficient usage of the limited energy resource. A fuzzy logic system is exploited in order to dynamically determine the path re-selection period and compose the routing path. The simulation results show that up to 50% of the energy is saved by applying the proposed method.

• Food Science and Preservation
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• v.14 no.3
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• pp.233-238
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• 2007

To develop a new quality control method for evaluation of Korean instant noodle soups, the chemical characteristics of roasted red pepper powder(RRP), mixed with red pepper seasoning oil, were investigated during storage at $65^{\circ}C$ for 6 weeks. The chemical composition was not significantly changed after 6 weeks of storage(P>0.05). The pH value decreased gradually while the acid value increased during storage. Both the American Spice Trade Association(ASTA) value that indicates redness of red pepper, and the CIE $L^*,\;a^*,\;and\;b^*$ values decreased remarkably during storage. The fatty acids of the RRP oil were mainly linoleic acid(55.1%), oleic acid(24.3%), and palmitic acid(13.9%). The composition of fatty acids was not significantly changed after 6 weeks of storage(P>0.05). In the free fatty acid(FFA) composition of the RRP oil, linoleic acid(32.4%) was the principal component. The total amount of FFA and the amount of each individual FFA increased remarkably during storage. The ratio of free unsaturated fatty acids to free saturated fatty acids increased during storage.

• Food Science and Preservation
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• v.24 no.6
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• pp.771-777
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• 2017

Although Doenjang is a representative traditional fermented food in Korea, made mainly from soybeans, it has been classified into a food group identified as having high sodium in the National Health and Nutrition Examination. It is necessary to develop a low sodium Doenjang to prevent the excessive sodium intake which may cause various diseases. However, the development of Doenjang with low sodium, without significant changes on quality, is an ongoing challenge. Therefore, the experiment was designed to reduce the salt content of the soaking water to 12.5-45%. The pH, saltiness. moisture, sodium, color, amino-type nitrogen, free amino acids and constituent amino acids composition of Doenjang were investigated to determine the effect of this salt reduction on the sensory quality of Doenjang. The reduction of sodium did not affect the pH, moisture and saltiness, and this changed maintained the same range as the control. The sodium content was reduced proportionally, and the amino acid nitrogen level was 500 mg%. Therefore, this study considered that a reduction of 25% of salt in the soaking water does not affect the quality of the Doenjang while reducing the sodium content of the final Doenjang.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.4
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• pp.449-454
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• 2010

Lately, airborne digital camera and airborne laser scanner in field of airborne surveying are used to build geography information such as digital ortho photo map and DEM(Digital Elevation Model). In this study, 3D position accuracy is compared medium format CCD camera RCD105 with airborne digital camera DMC. For this, test area was decided for aerial photograph. And using 1/1,000 scale digital map, ground control points were selected for aerial triangulation and check points were selected for horizontal/vertical accuracy analysis using softcopy stereoplotter. Accuracy of RCD105 and DMC was estimated by result of aerial triangulation and result of check points measurement of using softcopy stereoplotter. In result of aerial triangulation, RMSE(Root Mean Square Error) X, Y, Z of RCD105 is 2.1, 2.2, 1.3 times larger than DMC. In result of check point measurement using softcopy stereoplotter, horizontal/ vertical RMSE of RCD105 is 2.5, 4.3 times larger than DMC. Even though accuracy of RCD105 is lower than DMC, it is maybe possible to make digital map and ortho photo using RCD105.

• Journal of Life Science
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• v.17 no.11
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• pp.1517-1522
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• 2007

Gap junction channels formed by two adjacent cells allow the passage of small molecules up to ${\sim}\;1\;kDa$ between them. Hemichannel (connexon or half of gap junction) also behaves as a membrane channel like sodium or potassium channels in a single cell membrane. Among 26 types of connexin (Cx), $Cx32^*43E1$ (a chimera in which the first extracellular loop of Cx32 has been replaced with that of Cx43), Cx38, Cx46, and Cx50 form functional hemichannels as well as gap junction channels. Although it is known that Xenopus oocytes express endogenous connexin 38 (Cx38), its biophysical characteristics at single channel level are poorly understood. In this study, we performed single channel recordings from single Xenopus oocytes to acquire the biophysical properties of Cx38 including voltage-dependent gating and permeation (conductance and selectivity). The voltage-dependent fast and slow gatings of Cx38 hemichannel are distinct. Fast gating events occur at positive potentials and their open probabilities are low. In contrast, slow gatings dominate at negative potentials with high open probabilites. Based on hi-ionic experiments, Cx38 hemichannel is anion-selective. It will be interesting to test whether charged amino acid residues in the amino terminus of Cx38 are responsible for voltage gatings and permeation.

• Journal of Life Science
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• v.24 no.9
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• pp.952-958
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• 2014

The present study investigated the anti-obesity effects of Sparassis crispa (SC) on mice fed a high-fat (HF, 45 kcal% fat) diet. Mice were fed either a normal control diet and an HF diet or an HF diet supplemented with SC (1%, 3%, and 5%) for 12 weeks. The consumption of an HF diet compared to the NC group resulted in increases in body weight, the food efficiency ratio (FER), retroperitoneal and subcutaneous fat weights, cholesterol and triglyceride levels, fecal fat, and liver lipids. However, the administration of SC significantly decreased body weight gain, food intake, FER, cholesterol and triglyceride levels, and liver lipids in a dose-dependent manner. In particular, treatment with 5% SC significantly reduced the occurrence of fatty liver deposits and steatosis, which are associated with the increased adipocyte size in mice fed an HF diet. Therefore, these results suggested that dietary supplementation with SC exerts anti-obesity effects and could be used as a functional food to control obesity.

• Journal of Life Science
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• v.27 no.12
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• pp.1410-1414
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• 2017

Escherichia coli tryptophan synthase (TS) contains ${\alpha}_2{\beta}_2$, which catalyzes the final two steps in Trp biosynthesis. A molecular tunnel exists between the two active sites of ${\alpha}$ and ${\beta}$ subunits in TS. Via intersubunit communication, TS increases catalytic efficiency, including substrate channeling. The ${\beta}$ subunit of TS is composed of two domains, one of which, the COMM (communication) domain, plays an important role in intersubunit communication. The ${\alpha}$ subunit has a TIM barrel structure. This protein has functional regions at the C terminal of ${\beta}$ pleated sheets and in its loop regions. Three regions of the ${\alpha}$ subunit (${\alpha}L6$ [${\alpha}-loop$ L6], ${\alpha}L2$, and ${\alpha}L3$) are implicated in intersubunit communication. In the present study, conformational changes in ${\alpha}L6$ were monitored by measuring the sensitivity of mutant proteins in these regions to trypsin. The addition of a ${\alpha}$ subunit-specific ligand, D,L-${\alpha}$-glycerophosphate (GP), partially restored the sensitivity of mutant proteins to trypsin. In contrast, the addition of the ${\beta}$ subunit-specific ligand L-serine (Ser) resulted in varied sensitivity to trypsin, with an increase in PT53 (substitution of Pro with Thr at residue 53) and DG56, decrease in NS104 and wild type, and no change in GD51 and PH53. This finding may be related to several reaction intermediates formed under this condition. The addition of both GP and Ser led to a highly stable state of the complex. The present results are consistent with the current model. The method used herein may be useful for screening residues involved in intersubunit communication.