• 전기의세계
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• v.18 no.1
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• pp.33-37
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• 1969

한전은 1968년 11월 3일 오전 10시 04분을 기하여 154KV 전계통의 직접접지방식 전환을 단행하였다. 종전의 P.C(소고선륜) 중성점접지방식을 직접접지방식으로 전환한것으로서 전력사상 특기 할 만한 근대화사업이며 다년간을 두고 추진해온 중요과제였다. 전력계통의 확대와 복잡화는 선진국가에서도 실시하고 있는 직접접지방식의 채택을 불가변하게 하였고 또한 1차 AID송배전차관도 이의 채택을 조건부로 승인되었던 것으로서 1968년 이후에 건설되는 송변전기기는 직접접지계에서만 운전할 수 있는 절연Level 650KV급이 도입되어 부산화력발전소 3호기가 준공되는 1968년 10월말까지는 직접접지전환이 반드시 이루어져야 하는 실정에 놓여 있었다. 그런데 직접접지방식의 단점인 인접통신선에 미치는 유도장해를 해결하는 문제가 다년간을 두고 진지하게 검토되어 왔으나 해결이 늦어지고 있었다. 사유는 154KV 계통에 인근된 통신선이라면 체신부, 내무부, 교통부, 국방부등 여러기관의 것이 있는데, 유도장해보안방법과 유도보상비문제에 대하여 전력측(상공부, 한전)과 통신측(상기의 체신부등)의 견해차가 해소되지 않기 때문이었다. 그것이 1968년 5월에 와서 전력.통신쌍방이 범국가적입장에서 제반애로를 무릅쓰고 최소한의 투자로 가능한 범위내의 보안책으로서 우선 Arrester 보안방식을 채택하기로 합의되어 경제장관회의를 거쳐 시공하기에 이른것이다. 이 란을 빌려 이 사업의 필요성과 경위및 통신선유도장해방지를 위한 보안방식내용을 간단히 소개함으로써 앞으로 이 분야의 항구적인 유도대책연구에 다소나마 참고가 된다면 다행으로 생각하겠다.면서 예측강우의 질이 저하되기 시작하였으나 QPM을 합성함으로써 생산한 BQPF는 보다 신뢰성있고 양호한 결과를 얻을 수 있었다. 이러한 결과들은 향후 정량적 분포형강우 예측을 이용한 실시간 홍수유출 예측시 댐운영자는 리드타임(홍수선행시간)을 충분히 확보함으로서 안정적이고 예측 가능한 홍수조절을 하는데 도움을 줄 수 있을 것으로 기대된다. 이와 같이 다양한 단기저수지 유입량의 예측정보 제공으로 다목적댐 저수지 운영모형의 효용성을 제고하여 향후 실제 저수지 유입량 예측에 이용함으로써 저수지 단기운영효율 개선에 기여할 수 있을 것으로 사료된다.다. 이것은 여름철 강수량이 증가하고, 호우발생빈도, 특히 8월의 강수일수가 증가하고 있다는 것과 밀접한 관련이 있다. 여름과 가을에 우리나라에 영향을 미치는 태풍의 수는 뚜렷한 추세를 보이지 않으나, 2002년 루사, 2003년 매미로 인하여 각각 6조원, 4조원 이상의 막대한 피해가 발생하였다. 태풍에 의한 피해액은 GDP 대비 약 0.9%(태풍 루사)로 최근 경제상장률과 비교해 보면, 상당한 비율을 차지한다. 우리나라에 영향을 미치는 태풍은 연근해의 해수면 온도가 높아지면 세기가 강해질 가능성이 높다. 폭설과 한파일수도 평년대비 최근 10년 감소하였고 일최저기온이 영하 $10^{\circ}C$ 이하인 날도 연간 발생일수가 감소하였다. 최근 10년간 우리나라 기후의 변화특성은 기온상승과 더불어 서리종료일이 앞당겨지고 열대야가 증가하고 폭설, 한파, 겨울철 일최저기온 영하 10도 이하인 날의 감소 등이 나타나고, 여름철 재해의 원인인 호우일수는 증가하는 추세이다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.309-314
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• 2002

Rhtological properties of surimi gel from white fishes by acid (acid surimi) and alkali (alkali surmi) process and effect of chemicals on gelation were investigated by punch and dynamic tests. The breaking force and deformation values of heat-induced gel of acid surimi were less than their values of alkali and conventional surimi gel, and whiteness was greatly decreased, Gel point of acid surimi was decreased but it of alkali surimi was increased with increasing moisture content in the range of 80 to $85\%$. Storage modulus of acid surimi was the highest vaule in pH 6.8, but that of alkali surimi showed high value at neutral and slightly alkali pH. Propylene glycol increased storage modulus in $20\~50^{\circ}C$, hut urea and 2-mercaptoethanol suppressed it. Potassium bromide improved storage modulus in $20~80^{\circ}C$, The results suggest that alkai process is used for making surimi instead of conventional method.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.2
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• pp.99-104
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• 2007

The skin barrier function is one of the vital functions. Horny layer and epidermis among various skin layers play an important role in protecting body from environmental insults. Stratum corneum is completely formed by differentiation processes from the basal layer and newly formed corneocytes push the older ones from skin surface. In this study we investigated changes of various parameters - capacitance, transepidermal water loss (TEWL), pH and amount of removed corneocytes - according to the stratum corneum's depth. We removed the stratum corneum using tape stripping technique. We found that uppermost stratum corneum play an important role in skin surface moisturization and lower stratum corneum in protecting transepidermal water loss. In addition, skin pH is more acidic than surface pH. In the stratum corneum, skin pH is mote acidic in the deeper layer. Furthermore amount of removed corneocyte is also decreased according to depth because of stronger cell-cell union strength. From these results we suggest that stratum corneum has different characteristics depending on their position.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.27-34
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• 1987

The present paper was attempted to obtain the basic date concerning a reasonable preparing method and optimum fermentation conditions of Kochujang (Red pepper paste). To establish the standard quality of Kochujang, the chemical compositions and the volatile components of Kochujang was discussed. The native Kochujang collected from 80 households contained 40.51% of moisture, 6.00% of salts, 3.25 % of crude fat, 10.30 % of crude ash, pH 4.79, 9.28ml of tillable acidity. 19.60% of reducing sugar, 179.51 mg/100g of amino nitrogen and 4.43% of total nitrogen. The volatiles of Kochujang were extracted by a steam-distillation under the reduced pressure and determined by gas chromatography-mass spectrometry (GC-MS). Total volatile components identified in the native Kochujang were 46 components, i. e., 30 components in neutral fraction, 8 components in phenolic fraction and 8 components in acidic fraction, respectively. But no components were detected basic fraction.

• Korean Journal of Remote Sensing
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• v.34 no.6_3
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• pp.1383-1398
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• 2018

Sea surface wind is one of the most fundamental variables for understanding diverse marine phenomena. Although scatterometers have produced global wind field data since the early 1990's, the data has been used limitedly in oceanic applications due to it slow spatial resolution, especially at coastal regions. Synthetic Aperture Radar (SAR) is capable to produce high resolution wind field data. KOMPSAT-5 is the first Korean satellite equipped with X-band SAR instrument and is able to retrieve the sea surface wind. This study presents the validation results of sea surface wind derived from the KOMPSAT-5 backscattering coefficient data for the first time. We collected 18 KOMPSAT-5 ES mode data to produce a matchup database collocated with buoy stations. In order to calculate the accurate wind speed, we preprocessed the SAR data, including land masking, speckle noise reduction, and ship detection, and converted the in-situ wind to 10-m neutral wind as reference wind data using Liu-Katsaros-Businger (LKB) model. The sea surface winds based on XMOD2 show root-mean-square errors of about $2.41-2.74m\;s^{-1}$ depending on backscattering coefficient conversion equations. In-depth analyses on the wind speed errors derived from KOMPSAT-5 backscattering coefficient data reveal the existence of diverse potential error factors such as image quality related to range ambiguity, discrete and discontinuous distribution of incidence angle, change in marine atmospheric environment, impacts on atmospheric gravity waves, ocean wave spectrum, and internal wave.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.172-181
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• 2023

In order to raise the self-sufficiency rate of domestic forage and obtain informations necessary for production of high-quality winter forage, forage yield and feeding value were analyzed in the above-ground parts of a winter wheat 'Cheongwoo' harvested at five different growth stages, and the appropriate harvest time was determined. The yield increased until 30 days after heading, and then decreased afterwards. The proportion of spike in the above-ground part was less than 40% until 30 days after heading, but increased to more than 60% afterward. At 30 days after heading, the protein content and relative feed value (RFV) also reached peaks, while acid detergent fiber (ADF) and neutral detergent fiber (NDF) were low. The mineral nutrient contents are within the standard range required for feeding ruminant livestock or do not exceed the maximum allowable level. Therefore, the best time to harvest above-ground parts of a winter wheat 'Cheongwoo' for use as a forage for feeding ruminant livestock is around 30 days after heading, when considering forage yield and feed values. As a result it would match well in time with the transplantation of rice seedlings or the sowing of rice-alternative field crops in the double cropping system.

• Journal of the Korean Society of Radiology
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• v.84 no.4
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• pp.911-922
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• 2023

Purpose To compare small bowel distension and side effects between a diluted polyethylene glycol (PEG) solution and a low-density (0.1% w/v) barium sulfate suspension (LDBSS) for CT enterography (CTE) preparation. Materials and Methods Total 173 consecutive patients who underwent CTE were enrolled in this study. The LDBSS (1 L) was used in 50 patients, and the diluted iso-osmotic PEG solution (1 L) was used in 123 patients. Two blinded radiologists independently scored jejunal and ileal distensions on a 5-point scale. To compare side effects between the two groups, the patients reported whether they had immediate complications after the administration of the oral contrast media. Results For ileal and jejunal distension, the diluted PEG solution showed no difference from the LDBSS for either reader (ileum: reader 1, median, 4; 4, interquartile range, 3-4; 3-4, p = 0.997; reader 2, median, 4; 4, interquartile range, 3.3-4.0; 3-4, p = 0.064; jejunum: reader 1, median, 2; 2, interquartile range, 2-3; 2-3, p = 0.560; reader 2, median, 3; 2, interquartile range, 2-3; 2-3, p = 0.192). None of the patients complained of immediate complications following administration of either of the oral contrast media. Conclusion The diluted PEG solution showed comparable bowel distension compared to LDBSS and no immediate side effects; thus, it can be a useful alternative.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.99-110
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• 2018

In this study, oil of Platycodon grandiflorum seeds was prepared using supercritical carbon dioxide extraction (SCE) and its physicochemical indices as a new edible oil were investigated. Compared to Soxhlet solvent extraction, SCE under the condition of 6,000 psi at $40^{\circ}C$ produced more oil, especially from the roasted seeds to 32.7%. TLC analysis showed triacylglycerols accounted for most of the oil obtained from roasted Platycodon grandiflorum seeds by SCE similarly to commercial soybean oil or perilla seeds oil. The oil had highly unsaturated lipid with considerable amount of linoleic acid(73.27%) much more than two commercial oils followed by oleic acid(13.16%). Physicochemical properties of the oil were as follows; specific gravity, 0.92; dynamic viscosity, 45.37 cP; refractive index, 1.48; color, L=47.30, a=-3.69, b=25.72; iodine value, 141.57 g $I_2/100g$ oil; saponification value, 191.21 mg of KOH/g of oil; acid value, 2.60 mg of KOH/g of oil. Among those, refractive index, viscosity and iodine value, which were related to unsaturation degree of lipid, were ranged between those of two commercial oils. The oxidation stability of oil(2.03 hr) was also ranged between less stable perilla seeds oil(1.79 hr) and more stable soybean oil(2.94 hr) based on the induction time measured by Rancimat assay. In addition to extraction yield increase, seeds roasting provided further benefits such as reductions of cholesterol ester content and acid value without change in fatty acid composition. In conclusion, oil was extracted from the roasted Platycodon grandiflorum seeds at high yield by supercritical carbon dioxide and it seemed to have proper characteristics as a edible oil.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.561-570
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• 2008

This study aimed to determine the effects of freeze-dried onion powder (OP) which contains rich in quercetin (22 mg/10 g) on hyperlipidemic participants. Fourteen participants (total cholesterol level in plasma $270.8{\pm}21.4mg/dL$) $40{\sim}59$ years of age who were diagnosed as hyperlipidemia by a physician at Fatima Hospital in Changwon took part in this study for 12 weeks. We investigated the anthropometric data and dietary habit by using questionnaires. Also, blood samples were collected from the patients in fasting before and after this 12 weeks intervention study. 78.6% of the patients showed interest in health diet management and weight control; however, they also showed some problems in their dietary habit (meal irregularity, food choice, calorie nutrient balance, high fat and cholesterol etc.) and life style (smoking, eating out, alcohol intake) that could have adverse effect on hyperlipidemic therapy. Most participants (85.7%) thought that OP was good for their health. The total cholesterol and LDL-cholesterol significantly decreased with OP intake. The HDL-cholesterol increased and the Atherogenic index (AI) significantly decreased. Regarding the correlations of dietary habit and life style with anthropometric and biochemical factors, the alcohol intake level was significantly correlated with the frequency of eating out and body mass index (BMI). Exercise level showed positive correlation with HDL-cholesterol and negative correlation with atherogenic index (AI). These results suggest that the intake of polyphenol rich onion may decrease the risk of hyperlipidemia by reducing cholesterol level. We consider these hypolipidemic effects of OP as a possible functional food. However, further research such as a well designed longterm clinical study with experimental and placebo groups is needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.868-875
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• 2017

The aim of the present study was to investigate antioxidant nutrient intake and risk of metabolic syndrome based on stress level in rural Korean women. Subject were participants from the Multi-Rural Communities Cohort Study, which was a part of the Korean Genome and Epidemiology Study. According to scores of the Psychosocial Well-Being Index Short-Form, a total of 10,111 subjects were classified into 'low stress group (n=8,015)' from 0 to 26 points and 'high stress group (n=2,096)' above 27 points. Data were collected using self-administered questionnaires, anthropometric measurements, and blood chemical analysis. Dietary nutrient consumption was assessed by a semi-quantitative food frequency questionnaire. High stress group showed lower intake of antioxidant nutrients, such as vitamin A, vitamin C, vitamin E, folate, zinc, and carotene compared to the low stress group. Intake of fruits and vegetable was lower in the high stress group compared to the low stress group. Subjects with high stress showed higher risk of hypertension [odd ratio (OR), 95% confidence interval (CI)=1.226 (1.112~1.351)] and hypertriglyceridemia [OR, 95% CI=1.227 (1.110~1.356)] than subjects with low stress. High stress group had a significantly greater odds ratio for metabolic syndrome compared with the low stress group [OR, 95% CI=1.216 (1.101~1.342]). Thus, the present study suggests that high stress might be associated with low intake of antioxidant nutrients and high risk of metabolic syndrome in rural Korean women.