• Proceedings of the KSRS Conference
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• v.2
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• pp.909-912
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• 2006

In this paper a method for remotely-sensed assessment of eutrophication was experimented. The water samples were collected for analysis of COD (chemical oxygen demand) and nutrients concentration, and the remote sensing reflectance data at the sampling points were synchronously measured using above-water method in two cruises, which were conducted in the Pearl River Estuary in January 2003 and January 2004 respectively. Based on the in-situ data the local algorithms for estimation of concentration of nutrients (P and N) and COD were developed by Partial Least Squares (PLS) regression. The algorithms were then applied to atmospheric-corrected SeaWiFS data and the COD and nutrients concentration in Pearl River Estuary were estimated. And then the assessment of eutrophication was carried out by comparison of the estimated nutrients and COD value with the water quality standard. The results show that the whole estuary is seriously in eutrophication.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.2
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• pp.365-374
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• 1996

Finite wordlength effects of the FS-1016 CELP(Code Excite Linear Prediction) vocoder algorithm) is analyzed, and a block floating-Point implementation method is employed to improve the fixed-point performance. An efficient run-time integer wordlength estimation algorithm is developed, and the overall system performance. An efficient run-time integer wordlength estimation algorithm is developed, and the overall system performance is verified in real-time using a TMS320C50 emulation board. Autoscaler software that conducts simulation-based automatic scaling to provide a floating-point like programming environment is used for this application development.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.4
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• pp.210-213
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• 2017

In this paper, we analyzed the structural design and electrical characteristics of a 3.3 kV super junction FS IGBT as a next generation power device. The device parameters were extracted by design and process simulation. To obtain optimal breakdown voltage, we researched the breakdown characteristics. Initially, we confirmed that the breakdown voltage decreased as trench depth increased. We analyzed the breakdown voltage according to p pillar dose. As a result of the experiment, we confirmed that the breakdown voltage increased as p pillar dose increased. To obtain more than 3.3 kV, the p pillar dose was $5{\times}10^{13}cm^{-2}$, and the epi layer resistance was $140{\Omega}$. We extracted design and process parameters considering the on state voltage drop.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.344-349
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• 2009

동해의 SeaWiFS 클로로필-$\alpha$에서 나타나는 스펙클(speckle) 오차를 제거하고 Level-2에서 Level-3로의 자료합성을 실시하였다. 1998년부터 2007년까지 10년간 클로로필-$\alpha$의 시공간 변동성을 고려하여, 월 평균값으로 표준화된 공간적 표준 편차가 $7mg/m^3$ 이상 될 때를 경계 값으로 스펙클 제거기준을 설정하였다. 농도경사가 큰 전선지역과 연안으로부터 10-50 km 이내 지역은 제거 기준을 $12mg/m^3$ 이상으로 알고리즘을 구성하였다. 스펙클 제거 결과, 자료는 그대로 보존되고 스펙클이 존재하는 화소의 값만 줄어들었다. 특히 스펙클이 자주 발생하는 겨울철 클로로필 자료의 농도변화가 크게 나타났으며 스펙클이 많이 나타나는 시기에는 $5^{\circ}\times5^{\circ}$영역의 평균값이 10%이상 감소하는 결과를 보였다.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.209-215
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• 2002

Much effort has been made in the radiometric calibration of the ocean scanning multispectral imager (OSMI) since after the successful launch of KOMPSAT-1 in 1999. A series of calibration coefficients for OSMI detectors were obtained in collaboration with the NASA Sensor Intercomparison and Merger for Biological and Interdisciplinary (SIMBIOS) project office. In this study, we compare the OSMI level-2 products (e.g., chlorophyll-a concentration) calculated from the NASA cross-calibration coefficients with the SeaWiFS counterparts. Sample study areas are some of diagonostic data sites recommended by the SIMBIOS working group. We will present the preliminary results of this comparative study.

• Korean Journal of Remote Sensing
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• v.16 no.4
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• pp.315-325
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• 2000

Observations were made to validate ocean color algorithms in the Ulleung Basin, East Sea in May 2000. Small scale and meso-scale surveys were conducted for the validation of ocean color products (nLw: normalized water-leaving radiance and chlorophyll concentration). There were discrepancies between SeaWiFS and in situ nLw showing the current aerosol models of standard SeaWiFS processing software are less than adequate (Gordon and Wang, 1994). Applying the standard SeaWiFS in-water algorithm resulted in an overestimation of chlorophyll concentration. This is because that CDOM absorption was higher than the estimated chlorophyll absorption. TSS concentration was also high. Therefore, the study region deviated from Case 1 waters. The source of these materials seems to be the entrainment of coastal water by the Tsushima Warm Current. Study of the bio-optical properties in other season is desirable.

• Proceedings of the KSRS Conference
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• v.2
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• pp.913-916
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• 2006

Spatial distribution, seasonal and interannual variability of chlorophyll a concentration in Okhotsk Sea from SeaWiFS data between 2001 and 2004 were describe. An Empirical Orthogonal Function method was applied for analysis data. The ten modes described about 85% of total variance. Two maxima were defined - more intensive in spring and weaker in autumn. The first mode showed zones with chlorophyll a concentration during maximum bloom. The second mode specified timing of spring bloom in various regions in Okhotsk Sea. Analysis of SeaWiFS data indicated connection between highest chlorophyll a concentration and sea surface temperature limits during spring bloom. Similar relation was not found during fall bloom.

• The Korean Journal of Community Living Science
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• v.23 no.2
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• pp.129-136
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• 2012

Dioxins are chemical substances that are not properly decomposed degradation under natural photochemical, biological and chemical conditions in the environment, and bio-accumulate through the food chain, so pose a risk of causing adverse effects to human health and the environment. Ninety seven percent of human exposure to dioxins comes through meat, fish, dairy consumption and so on. Pork is the largest proportion meat aspect of daily intake in the Korean food. Pigs are three times more than Cattle in terms of breeding population and production amount in the world, and the amount is increasing every year. Therefore, it is necessary to monitor the exposure level of dioxins in pig's body. Also, it is required to evaluate the presence of these chemical substances in the pig's feed grain such as corn, soybeans, and tallow. The purpose of this study was to evaluate PCDD/Fs in pig's feed to search the origin of PCDD/Fs. Feed samples obtained were wheat from East Europe, corn from South America and America, soybean meal from Korea, America, South America and India and tallow from Korea. The preparation of samples was based on the EPA method 1613. Instrumental analysis was based on the use of high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS). The concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PCDD), which are the most toxic potent dioxins, were not observed in any of the samples. However OCDD was detected in most of the samples. The TEQs in the feed samples were ranged from 0 pg TEQ/g to 0.09841 pg TEQ/g. Especially, the high level of TEQs was observed in the samples of wheat from East Europe and soybean meal from Korea.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.2
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• pp.149-157
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• 2020

Today, due to the large amount of data duplication caused by the increase in user data, various deduplication studies have been conducted. However, research on personal storage is relatively poor. Personal storage, unlike high-performance computers, needs to perform deduplication while reducing CPU and memory resource usage. In this paper, we propose an adaptive algorithm that selectively applies fixed size chunking (FSC) and whole file chunking (WFH) according to the file type and size in order to maintain the deduplication rate and reduce the load in personal storage. We propose an algorithm for minimization. The experimental results show that the proposed file system has more than 1.3 times slower at first write operation but less than 3 times reducing in memory usage compare to LessFS and it is 2.5 times faster at rewrite operation.

• Food Science and Preservation
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• v.18 no.2
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• pp.256-265
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• 2011

To investigate the effect of a solar salt on Kimchi fermentation, Chinese cabbages were brined with four-years aged solar salt (FS), one-year aged solar salt (OS), and purified salt (PS). The Kimchi was fermented at $7^{\circ}C$ for 33 days. The changes in pH and acidity of the Kimch brined with PS was slower than those of Kimchis brined with FS and OS. In the Kimchis with FS and OS, lactic acid bacteria (LAB) counts increased from 7.10~7.22 log CFU/mL at 0 day to 9.26~9.42 log CFU/mL at 12 days, after which counts slightly decreased to 8.04~8.75 log CFU/mL by 33 days of fermentation. The LAB counts of the kimchi with PS slowly increased from 7.24 log CFU/mL at 0 day to 8.99 log CFU/mL at 27 days, after then which counts sharply decreased to 7.92 log CFU/mL by 33 days of fermentation. Yellowness (b) color values of the kimchi with PS (59.10) was higher than the Kimchi with FS (53.68) and the Kimchi with OS (53.77). Hardness of the Kimchi with FS was more firm than the other Kimchis after 33 days storage. Sensory evaluation of the Kimchi with FS showed higher score than that of the other Kimchis.