• Nuclear Engineering and Technology
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• v.49 no.1
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• pp.54-70
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• 2017

The accumulator is a passive safety injection device for emergency core cooling systems. As an important safety feature for providing a high-speed injection flow to the core by compressed nitrogen gas pressure during a loss-of-coolant accident (LOCA), the accumulator injects its precharged nitrogen into the system after its coolant has been emptied. Attention has been drawn to the possible negative effects caused by such a nitrogen injection in passive safety nuclear power plants. Although some experimental work on the nitrogen injection has been done, there have been no comparative tests in which the effects on the system responses and the core safety have been clearly assessed. In this study, a new thermal hydraulic integral test facility-the advanced core-cooling mechanism experiment (ACME)-was designed and constructed to support the CAP1400 safety review. The ACME test facility was used to study the nitrogen injection effects on the system responses to the small break loss-of-coolant accident LOCA (SBLOCA) transient. Two comparison test groups-a 2-inch cold leg break and a double-ended direct-vessel-injection (DEDVI) line break-were conducted. Each group consists of a nitrogen injection test and a nitrogen isolation comparison test with the same break conditions. To assess the nitrogen injection effects, the experimental data that are representative of the system responses and the core safety were compared and analyzed. The results of the comparison show that the effects of nitrogen injection on system responses and core safety are significantly different between the 2-inch and DEDVI breaks. The mechanisms of the different effects on the transient were also investigated. The amount of nitrogen injected, along with its heat absorption, was likewise evaluated in order to assess its effect on the system depressurization process. The results of the comparison and analyses in this study are important for recognizing and understanding the potential negative effects on the passive core cooling performance caused by nitrogen injection during the SBLOCA transient.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.5
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• pp.39-46
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• 2007

Research on human identification in ubiquitous environment has recently attracted a lot of attention. As one of those research, gait recognition is an efficient method of human identification using physical features of a walking person at a distance. In this paper, we present a human shape extraction and tracking for gait recognition using geodesic active contour models(GACMs) combined with mean shift algorithm The active contour models (ACMs) are very effective to deal with the non-rigid object because of its elastic property. However, they have the limitation that their performance is mainly dependent on the initial curve. To overcome this problem, we combine the mean shift algorithm with the traditional GACMs. The main idea is very simple. Before evolving using level set method, the initial curve in each frame is re-localized near the human region and is resized enough to include the targe region. This mechanism allows for reducing the number of iterations and for handling the large object motion. The proposed system is composed of human region detection and human shape tracking modules. In the human region detection module, the silhouette of a walking person is extracted by background subtraction and morphologic operation. Then human shape are correctly obtained by the GACMs with mean shift algorithm. In experimental results, the proposed method show that it is extracted and tracked efficiently accurate shape for gait recognition.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.3
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• pp.442-458
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• 2008

This paper aims to examine the ways in which project-based organizations (PBOs) are embedded in social networks and geographical clustering in the case of TV drama industry. PBOs refer to a variety of temporary organizational forms for the performance of tasks as to integrate diverse and specialized intellectual resources. PEOs as a flexible and innovative mode of organizing knowledge resources are becoming increasingly worthy of attention in emerging the creative economy. Evidence from interviews with core persons of PEOs like producers, directors, and writers reveals that the key operational mechanism of the project form of organization is based on the highly socialized networks via individual's reputation and past experiences. In other words, the project activity in TV drama is embedded in networks which are socially constructed. Also the geographical clustering plays an important role in PBOs and project practices in TV drama are constructed around a high degree of spatial clustering. PBOs are clustering in Kang-nam and Yeouido, where are located in independent production companies and broadcasting stations. It means that the project formation in TV drama requires geographically-clustered networks of human resources, and socially, culturally and geographically embedded latent networks of interpersonal relationships are a necessary condition of POBs in the TV drama industry.

• Journal of Korean Society of Steel Construction
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• v.15 no.6 s.67
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• pp.683-691
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• 2003

Recently, the steel has been increaseingly used as an integrated part of high-rise buildings, which often composed of steel structures, steel reinforced concrete structures and composite structures. The steel base is designed to transfer the stresses induced from steel column to the reinforced concrete footing through the base plate. However, in the design of steel structures and steel reinforced concrete structure, it is generally difficult to evaluate the bearing strength of the steel base subjected to large axial force. Furthermore, the material used in steel base is quite different from those used in other connections and a load transferring mechanism of steel base is very complicated in nature. Therefore, a special attention must be placed in design and construction of steel base. In generally, the bearing strength test and research of the steel base subjected to concentrated load are carried out. But, in the design of the structures, uniaxial eccentric load is loaded to the steel base of the steel structures. In this research, the bearing strength and the me of failure considering eccentric loads and eccentric length, were experimented when eccentric load is loaded to the steel base of steel structures. Based on the test results, a basic design reference is suggested for a reasonable design of steel structures, steel reinforced concrete structures and composite structures.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.688-693
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• 2002

The anticarcinogenic effects of various food components have received much attention in recent years. However mechanism of anticarcinogens in food materials on cancer cells have rarely been investigated. This study was performed to investigate the effects on the cytotoxicity and quinone reductase (QR) activity of Allium tuberusum (AT) on the human cancer cells. The six partition layers which are methanol (ATM), hexane (ATMH), ethylether (ATMEE), ethylacetate (ATMEA), butaonl (ATMB) and aqueous (ATMA) of Allium tuberusum were screened for their cytotoxic effects on HepG2, MCF-7, HeLa and SK-N-MC cells by the MTT assay. Among the six partition layers, ATMEE had the strongest cytotoxic effect at concentration of $150\;{\mu}g/mL$ which resulted over 95% on HepG2, HeLa, MCF-7 and SK-N-MC cell lines. The ATMEA also showed significant cytotoxic effect on HepG2 and SK-N-MC cell lines. The ATMB showed the highest induction activity of QR on HepG2 cells among the other partition layers. QR activity of HepG2 cells, grown in the presence of ATMB at the concentration of $50\;{\mu}g/mL$, was increased by 3.9 times, compared to the control value of 1.0. Based on these results, the ATMEE and ATMB may have potentially anticarcinogenic and chemopreventive activities.

• Korea Science and Art Forum
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• v.37 no.2
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• pp.275-292
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• 2019

This study was initiated with the attention of demanding new and diverse approaches, we're talking familiar with imitations in the design process like a way to draw a image. So I studied a convergence of humanities and visual arts with the understanding and conceptual approach of the formless. The purpose of this study is to develop formless languages and to organize practical courses which are to enable deeper research and design expression on theoretical approaches and explanations of outcomes required before and after the process when we practice in connection with the formless. The method of this study is to draw detailed items from selected words through advanced researches, work and author researches and practice teaching. The results of the study I proposed the formless language that is related to the horizontality in spatial positioning system, and pulse in the separation of space and time, and entropy in structural orders of the system, and base materialism in the limitation of matter as the operating mechanism and parent item of formless. And those elements are related with shape, size, shading, color, texture, space, structure as visual elements of formative elements and those have various adjectival meanings as the subordinate concept. So I presented an education materials of basic design which is to enable understanding and expressing the formless language in the overall process of formless visual art(theoretical approach, practice course, presentation, etc.). Based on these study results, I hope that this educational materials will be used as educational contents that makes them express and understand different new beauties, and a role that reveals social identity, and a reference for research on a formless visual arts.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.316-322
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• 2019

Helicobacter pylori, a gram-negative bacterium, is one of the risk factors that induces gastritis and gastric cancer. Therefore, much attention has been paid to the compounds that inhibit bacterial growth or eradicate bacteria. Evodiae fructus (EF), the fruit of Evodia rutaecarpa, has been used for treating diarrhea and abdominal pain. EF extract was already found to inhibit the growth of H. pylori. However, to the best of our knowledge, the effect of EF on the virulence factors of H. pylori has not been reported. In this study, when comparing the minimum inhibitory concentration (MIC) of the different methanol concentration extracts, the 95% methanol extract (EF95) showed the lowest MIC value. EF95 extract suppressed the expressions of cagA, vacA and ureB, but interestingly, it up-regulated the expression of ureA. A decrease in production of ammonia in the culture medium and the cell lysates indicated that EF95 inhibited the urease activity in H. pylori, which was the result of EF95 inhibiting the ureB expression. Although the mechanism by which EF95 extract regulates the virulence factors in H. pylori needs further study, EF95 could be used for treatment of gastric troubles induced by H. pylori.

• The Journal of Korean Philosophical History
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• no.39
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• pp.221-235
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• 2013

Through the comparative analysisand inductive research on main creation styles of Chinese, American and Japanese animation films, a conclusion can be given out, which means that the animation film style of each country can hardly be formed without their own traditional painting art, aesthetics habits and ways of thinking. It is these characteristics that form their unique animation film style. America emphasizes realism art, development and utilization of new technology, Japan pays sepcial attention totraditional painting art and comic stories. In business aspect, they bring about different business models relying on the experience of satisfying the diverse needs of domestic and global entertainment markets. When it comes to the content field, they carry forward universal values and meet the individualistic heroismso that a variety of business animation films and art animation films find their ways into the global market and acquire great popularity among audiences from all over the world. Through the comparasion of American and Japanese animation films, a new view to analyze the animation films of China is created. Animation creation is largely based on the need of socialist ideology from 50s to 80s. Even though the purposes of animation film creations returned to satisfying the diverse requirements of commercial markets and audiences, the consequences, such as the break gap of creations and talents, the lack of diverse creative styles and commercial market operation mechanism, sitll affect China's animation films today. Japan found thier position from the American model and became successful. Nowadays, China need find our own creative style and position from American model and Japanese model. And the systematic reformings that are detailed in the government managements, industry standards, internationalized talents cultivation and accumulation are the essential point.

• Journal of the Microelectronics and Packaging Society
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• v.29 no.3
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• pp.25-29
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• 2022

Recently, the importance of electronic packaging technology has been attracting attention, and heterogeneous integration technology in which chips are stacked out-of-plane direction is being applied to the electronic packaging field. The 2.5D integration circuit is a technology for stacking chips using an interposer including TSV, and is widely used already. Therefore, it is necessary to make the interposer mechanically reliable in the packaging process that undergoes various thermal processes and mechanical loadings. Considering the structural characteristics of the interposer on which several thin films are deposited, thermal stress due to the difference in thermal expansion coefficients of materials can have a great effect on reliability. In this study, the mechanical reliability of the metal pad for wire bonding on the silicon interposer against thermal stress was evaluated. After heating the interposer to the solder reflow temperature, the delamination of the metal pad that occurred during cooling was observed and the mechanism was investigated. In addition, it was confirmed that the high cooling rate and the defect caused by handling promote delamination of the metal pads.

• Korean Journal of Biological Psychiatry
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• v.28 no.1
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• pp.13-22
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• 2021

Objectives Despite growing attention to anxiety in bipolar disorder (BD), little research has assessed anxiety symptoms in the course of BD. The current prospective follow-up study examines the influence of subjectively and objectively measured anxiety symptoms on the course of BD. Methods A total of 49 patients with BD were followed-up prospectively for average of one year at an average of four months interval. The Korean version of the Beck Anxiety Inventory (K-BAI), the Hamilton Anxiety Rating Scale, heart rate variability (HRV) were used to measure anxiety subjectively, objectively and physiologically. Participants were divided into high and low anxiety groups based on their K-BAI scores. Kaplan-Meier survival analysis was performed to compare the recurrence of mood episode, suicide attempt, emergency room visit, and psychiatric hospitalization between two groups. Mediators were investigated with Cox proportional hazards models. Results Compared to the low anxiety group, the high anxiety group reported significantly higher impulsiveness (p = 0.016) and lower high frequency component on HRV (p = 0.007) after controlling for severity of BD. Regarding survival analysis, the high anxiety group showed hastened depressive episode recurrence (p = 0.048) and suicidal ideation was the mediator of the hazard ratio (HR) 1.089 (p = 0.029) in the Cox model. Moreover, the high anxiety group showed a tendency of accelerated suicide attempt (p = 0.12) and impulsivity was the risk factor of suicide attempt (HR = 1.089, p = 0.036). Conclusions This interim analysis of prospective study suggests that high anxiety level in BD may anticipate unfavorable course. Further studies are needed to understand the multifactorial mechanism of anxious bipolar patients.