• Journal of the Microelectronics and Packaging Society
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• v.27 no.2
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• pp.1-10
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• 2020

The technology and market size of image sensors continue to develop thanks to the release of image sensors that exceed 100 million pixels in 2019 and expansion of black box camera markets for vehicles in addition to existing mobile applications. We review the technology flow of image sensors that have been constantly evolving for 40 years since Hitachi launched a 200,000-pixel image sensor in 1979. Although CCD has made inroads into image sensor market for a while based on good picture quality, CMOS image sensor (CIS) with active pixels has made inroads into the market as semiconductor technology continues to develop, since the electrons generated by the incident light are converted to the electric signals in the pixel, and the power consumption is low. CIS image sensors with superior characteristics such as high resolution, high sensitivity, low power consumption, low noise and vivid color continue to be released as the new technologies are incorporated. At present, new types of structures such as Backside Illumination and Isolation Cell have been adopted, with better sensitivity and high S/N ratio. In the future, new photoconductive materials are expected to be adopted as a light absorption part in place of the pn junction.

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.611-623
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• 2024

The ISP-47 TOSQAN experiment was analyzed with containmentFOAM which is an open-source CFD code based on OpenFOAM. The containment phenomena taking place during the experiment are gas mixing, stratification and wall condensation in a mixture composed of steam and non-condensable gas. The k-ω SST turbulence model was adopted with buoyancy turbulence models. The wall condensation model used is based on the diffusion layer approach. We have simulated the full TOSQAN experiment which had a duration 20000 s. Sensitivity studies were conducted for the buoyancy turbulence models with SGDH and GGDH and there were not significant differences. All the main features of the experiments namely pressure history, temperature, velocity and gas species evolution were well predicted by containemntFOAM. The simulation results confirmed the formation of two large flow stream circulations and a mixing zone resulting by the combined effects of the condensation flow and natural convection flow. It was found that the natural convection in lower region of the vessel devotes to maintain two large circulations and to be varied the height of the mixing zone as result of sensitivity analysis of non-condensing wall temperature. The computational results obtained with the 2D mesh grid approach were comparable to the experimental results.

• Analytical Science and Technology
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• v.5 no.2
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• pp.185-190
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• 1992

A gas-jet assisted glow discharge lamp was attached to a conventional atomic absorption spectrophotometer in the place of a flame burner. To evaluate the accuracy of this method, the certified values and the analyzed values of SRM's were compared and atomic absorption sensitivity for five elements were also obtained. Factors affecting the sensitivity and areas for future improvement are discussed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.3
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• pp.137-145
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• 2014

We present a design sensitivity analysis(DSA) method for multiscale problems based on bridging scale decomposition. In this paper, we utilize a bridging scale method for the coupled system analysis. Since the analysis of full MD systems requires huge amount of computational costs, a coupled system of MD-level and continuum-level simulation is usually preferred. The information exchange between the MD and continuum levels is taken place at the MD-continuum boundary. In the bridging scale method, a generalized Langevin equation(GLE) is introduced for the reduced MD system and the GLE force using a time history kernel is applied at the boundary atoms in the MD system. Therefore, we can separately analyze the MD and continuum level simulations, which can accelerate the computing process. Once the simulation of coupled problems is successful, the need for the DSA is naturally arising for the optimization of macro-scale design, where the macro scale performance of the system is maximized considering the micro scale effects. The finite difference sensitivity is impractical for the gradient based optimization of large scale problems due to the restriction of computing costs but the analytical sensitivity for the coupled system is always accurate. In this study, we derive the analytical design sensitivity to verify the accuracy and applicability to the design optimization of the coupled system.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.326-331
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• 2006

The durability of recent motors is longer than the past one because there are the rapid technique development of the automobile industry and the vehicle maintenance of users. And then the importance of the durability test due to vibration is increased from day to day. So full vehicle and parts companies accomplish the durability test using various methods. The most public test method among them is the reliable field test but it bring on higher cost and period of the development process. The durability test using MAST(multi axis simulation table) is a solution in order to improve the development process of automobiles. Generally its excitation source uses the optimized road profiles that are obtained by the road test of belgian road, country road, cobbleston road and so on instead of a real field but the interrelations and influences accordingly vehicle damage are considered by a field test between specific roads and real fields in the first place. Therefore this study, in order to accomplish a basic research for the durability test using the MAST, performed on the real field driving test at various domestic roads and the results which are analyzed by PSD(power spectrum density) are compared with relative sensitivity among the roads. Consequently they can present a basic material for generation of road profiles which is applied to the durability test using MAST.

• 한국문예비평연구
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• no.65
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• pp.123-149
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• 2020

This study identified objective placeness throughout the writing of Na, Hye-seok, who was Korea's first female Western painter and early modern writer, and analyzed her spatiality around two keywords, "confined space" and "delay space." The investigator applied the concept of gender geography, which maintains that place experiences organize existence, and demonstrated the intrinsic aspects of placeness. First, confined spaces expressed the institutional contradictions of Joseon with the analogy of collapse and extinction. Inns and boarding houses were daily spaces and also temporary places of residence that she had to leave some day. Gyeongseong was a hybrid place of both success and failure. Secondly, Japan was a space of growth to study modernity and a delay space to escape from fear for Na. Her Western experiences underwent the procedure of discovering otherness inside a civilized state instead of self-colonization and asking questions about the places where she belonged. Na's place experiences and their connotations revealed in her writing show a gap between the ideal and reality of a subject facing her given destiny and between her inner conflicts. The present study demonstrated the daily conditions, social status, and characteristics of women through spaces beyond ideological placeness as a common idea, thus holding its significance. The specific daily and multiple nature produced in relations between a certain subject and the existential situation of a place will play significant roles in the theoretical extension of gender discourse in the future.

• The Journal of Society for e-Business Studies
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• v.21 no.1
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• pp.15-32
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• 2016

Online news on the Internet, as published open data, contain facts or opinions about a specific affair and hence influences considerably on the decisions of the general publics who are interested in a particular issue. Therefore, we can predict the people's choices related with the issue by analyzing a large number of related internet news. This study aims to propose a text analysis methodto predict the outcomes of events that take place in a specific place. We used topics of the news articles because the topics contains more essential text than the news articles. Moreover, when it comes to mobile environment, people tend to rely more on the news topics before clicking into the news articles. We collected the titles of news articles and divided them into the learning and evaluation data set. Morphemes are extracted and their polarity values are identified with the learning data. Then we analyzed the sensitivity of the entire articles. As a result, the prediction success rate was 70.6% and it showed a clear difference with other analytical methods to compare. Derived prediction information will be helpful in determining the expected demand of goods when preparing the event.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.712-714
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• 2003

The modifications taking place within the alluvial plains impart a larger extent of disturbances to hydrologic systems. The objective of the present investigation is to detect the sensitivity of multi-temporal image data from Landsat TM (Thematic Mapper) for finding out the land-cover/land-use changes associated with alluvial low land. The eastern coast of Chiba Prefecture, Japan, forms a very important geographic unit owing to the existence of a unique alluvial landform. The alluvial plain occupied in the study area is widely known as 'Kujukuri Plain'. The TM images have been classified by means of maximum likelihood supervised classifier and the extent of changes has been estimated.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.2205-2209
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• 2009

Nitrate contamination of groundwater is a wide-spread problem in both New Zealand and South Korea and has lead to eutrophication of receiving lakes and rivers. Denitrification in groundwater has the potential to reduce inputs of N to these receiving waters but quantification of the amount of denitrification taking place is difficult. A series of denitrification measurements have been carried out in the field at selected groundwater locations in New Zealand using a recently developed re-circulating well technique to increase sensitivity. This is an ongoing project and the methodology and sites are described and some preliminary results discussed. An overview of the collaborative research programme on in-situ groundwater processes (in which this denitrification project is a component) is provided.

• The Korean Journal of Ecology
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• v.21 no.4
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• pp.383-387
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• 1998

the geoecology of the alpine and subalpine belts of the Korean Peninsula, its component plant group, its environmental history, and climatic amplitudes of the arctic-alpine and alpine plants has reviewed and discussed. The present-day alpine and subalpine landscapes are likely to have been formed during the post-glacial warming phase. The disjunctive distribution of many alpine and subalpine plants, however, suggests a former continuous distribution of these both locally and on a broader, and the subsequent breakdown of a former continuous range into fragments as the climate ameliorated during the post-glacial warming phase. The presences of numerous arctic-alpine and alpine plants on the alpine and subalpine belts of the Korean Peninsula, are mainly their relative degree of sensitivity to high summer temperatures. The continued survivals of alpine species and landscape in Korea is in danger if global warming associated the greenhouse effect takes place.