• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.1
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• pp.159-168
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• 2010

In the recent years, power analysis attacks were widely investigated, and so various countermeasures have been proposed. In the case of block ciphers, masking methods that blind the intermediate results in the algorithm computations(encryption, decryption, and key-schedule) are well-known. The type conversion of masking is unavoidable since Boolean operation and Arithmetic operation are performed together in block cipher. Messerges proposed a masking type conversion algorithm resistant general power analysis attack and then it's vulnerability was reported. We present that some of exiting attacks have some practical problems and propose a new power analysis attack on Messerges's algorithm. After we propose the strengthen DPA and CPA attack on the masking type conversion algorithm, we show that our proposed attack is a practical threat as the simulation results.

• Journal of the Korean Chemical Society
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• v.57 no.4
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• pp.507-514
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• 2013

In this study, the characteristics of visually impaired elementary students' conceptions on dissolution were investigated. The semi-structured interviews about phenomenon of dissolution, uniformity of solution, conservation of mass on dissolving and volume change during dissolving were conducted with 4 fifth-grade elementary students with visual impairments (three were blind, and one had low-vision). Interviews were recorded and the data were analyzed after transcription. As a result, students with visual impairments knew well about the phenomenon of dissolution, uniformity of solution, and conservation of mass on dissolving, while they couldn't explain volume change during dissolving. Although students with visual impairments were found to have similar level of understanding with students without visual impairments, they had sounder understanding about uniformity of solution. However, students with visual impairments had superficial understanding based on phenomenal experiences. Some of students with visual impairments tried to give micro-level explanation. Based on these results, educational implications were discussed.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.189-194
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• 2018

This study reflects the current trend of the blind hiring culture focused on job competency rather than education specification as government initiative. In order to overcome the limitation of the existing document-oriented online recruitment process, we proposed a system architecture design of video interview system. In addition, we have evaluated the effectiveness through the development of prototype and performance experiment based on it. The proposed online video interview system is designed to combine intelligent Web technology to enable customized job matching and distant job coaching. This system is designed to reduce recruitment cost and opportunity cost of job seekers. Based on results derived from this study, commercialization of the proposed video interview system can be expected to be an practical online recruitment solution for the job competency based employment.

• Plant Resources
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• v.4 no.2
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• pp.75-84
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• 2001

Narcotic drugs generally refer to serious and habitual hidden rash such as opium, heroin, methyphetamin, nabinol, cocaine, and so forth. At present, narcotic drugs are spread unchecked and are causing a big social problem. So many countries and narcotists are making every effort to set up a barricade against narcotic drugs. And there is a limit suitable treatment for them. Thus Tuo Yin Tang Jiang is developed. As indicated by Chinese letters, Tuo Yin Tang Jiang(TYTJ) is a crude drug. It is a traditional chinese medicine developed by the study done from June in 1998 to June in 1999 that Hubeisheng was entrusted with by People's Republic of China. This study is a treatise on etiology and syntomatology of narcotism. TYTJ is a medicine which is in accord with Pharmacopeia of the People's Republic of Chinal) in order to remove from the body the toxic materials resulting from narcotic drugs such as opium and heroin. According to the standard diagnosis on narcotism, 105 cases are studied and treated at the Rehabilitation Center attached to Enshi Autonomous Region Hospital in Hubeisheng. 105 cases are divided into 2 groups by double-blind method. One is the experimental group which has 56 cases. The other is the control group which has 49 ones.13 cases among 105 cases are addicted by intravenously injections. 9 cases are by oral takings. It took 10 days for this experiment to be performed. Two groups didn't show a striking individual variation based on the age, gender, period of taking drugs, withdrawal symptoms, complication, and state of health. The experimental group had a higher effect of treatment than the control group had. TYTJ treats diseases effectively and has no side effect, irrespective of the serious or slight addiction to opium and morphine.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.1
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• pp.60-69
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• 1996

3-APPA는 생체내 물질 Υ-amino butyric acid와 유사한 구조를 갖는 물질로서 human fibroblasts 3-dimensional culture system 등의 in vitro 시험에서 collagen 합성촉진 효과, 세포증식 효과를 나타내며, hairless mouse를 이용한 동물시험에서도 collagen 합성이 증가되는 것으로 보고된 바 있다. 또한 피부 안정성에서도 우수한 결과를 보여줌으로서 화장품 분야에서 새로운 노화억제 물질로서 주목을 받게 되었다. 본 시험에서는 180명의 피검자를 대상으로 3개월간의 임상시험을 통하여 새로운 노화억제 물질인 3-APPA의 효능을 기존의 GABA 유사물질, aminopropane sulfonic acid와 비교하였다. 본 시험은 double-blind, randomized, vehicle-controlled clinical study로서 180명의 피검자를 APSA군, 3-APPA군, vehicle군으로 분류한 후 3개월간 매일 저녁 취침 전, 안면에 시험제품을 사용하도록 하였으며, 사용 전, 사용 1주후, 2주후, 6주후, 12주후 5회 설문지를 통하여 피부상태를 조사하였다. 각 설문내용은 피부 건조도, 피부 탄력도, 피부 주름량, 피부 윤기도, 피부 거칠기 정도에 대한 5개 질문으로 구성된 효능에 관한 질문과 흡수정도, 끈적임, 매끄러움, 보습력, 보습지속성, 전체적인 사용감에 대한 6개 질문으로 구성된 사용성에 관한 것이었다. 각 질문에 대하여는 매우 좋음 1점, 좋은 2점, 보통임 3점, 나쁨 4점, 매우 나쁨 5점 사이에서 답할 수 있도록 하였다. 시험 결과 APSA군은 6주와 12주후 피부 건조도, 피부 거칠기 항목에서 사용전에 비하여 유의한 차이를 나타내었다. 3-APPA군은 6주후 피부 건조도, 피부 거칠기, 피부 탄력도 항목에서 시료사용전에 비해 유의한 차이를 나타내었으며 12주후에는 피부 건조도, 피부 탄력도, 피부 윤기도, 피부 거칠기 항목에서 유의한 차이를 나타내었다. 12주후 APSA군은 피부 주름, 피부 탄력도 항목에서 vehicle 사용 피검자군에 비하여 유의적인 차이를 나타내었으나 3-APPA군은 피부 탄력도, 피부 주름량, 피부 윤기 항목에서 vehicle군에 비하여 유의적인 차이를 나타내었다. 결론적으로 3-APPA와 APSA 사이에 유의적인 차이가 있지는 않았으나 3-APPA군은 APSA군에 비하여 6주, 12주에서 사용전과 유의한 차이를 나타내는 항목이 많았으며 12주에서 vehicle과 유의적인 차이를 나타내는 항목도 많으므로 3-APPA가 APSA 보다 광범위한 피부노화 억제 효과를 갖는 물질이라고 할 수 있다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.4 s.34
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• pp.1-5
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• 1999

The purpose of this study was to determine the effect of IPBC(3-lodo-2-propynylbutylcarbamate) on dandruff caused by the anthropophilic fungus Malassezia furfur. The effects of IPBC on dandruff were examined by evaluating (a) the MIC value of IPBC using broth dilution method; (b) the remnant antimicrobial activity of IPBC containing shampoo on skin disc; (c) the antidandruff efficacy of 1.0 % IPBC containing shampoo in double blind clinical trial. To investigate the remnant antimicrobial activity of IPBC against Malassezia furfur, guinea pig-skin disc was washed with antidandruff shampoo and then the diameter of inhibition zone per disc was measured. For clinical trial, thirty healthy volunteers, aged 25-35, participated in 4 week study. At 0, 2, 4 weeks, examinations of scaling, itching on scalp were carried out. The MIC(Minimun Inhibition Concentration) values of IPBC range from 0.10 to 1.00${\mu}g/ml$ and it seems that IPBC is more effective in the MIC values than zinc pyrithione, selenium disulphide, piroctone olamine and comparable to ketoconazole, climbazole. When the remnant antimicrobial activity of IPBC shampoo on skin disc was determined, 0.5% IPBC shampoo and 2.0% Ketoconazole shampoo resulted in similar antimicrobial effect. In addition, 1.0%, 2.0% IPBC shampoo was more effective than 2.0% ketoconazole shampoo. After two and four-weeks of 1.0% IPBC shampoo treatment, there was significant reduction of scaling, itching in test group compared to control group. On the basis of these results, it can be concluded that 1.0% IPBC is more effective than 2.0% Ketoconazole in reducing dandruff. It seems that strong capacity of drug binding to the stratum corneum plays a role in its antidandruff effect since adsorption of active ingredients on scalp is very important factor in reducing dandruff.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.142-149
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• 2003

Blind hydraulic backfilling is a commonly used technique for subsidence control of the strata over unapproachable waterlogged underground excavations. In this investigation model studies on all the three variants of this technique, namely, hydro-pneumatic or air-assisted gravity backfilling, pumped-slurry backfilling and simple gravity backfilling, have been carried out in fully transparent models of the underground excavations. On examination of the filling process, it was revealed that in all the three cases, the basic process of filling occurs by sand transport along one or more meandering channels. The relative influence of sand, water and air flow rates on the area of filling from a single inlet point and the hydraulic pressure loss per unit length were studied in details. In hydro-pneumatic backfilling process, the air bubbles while moving upward through the meandering channels provide an additional buoyant force over and above the available hydraulic head. In this way the area of filling from a single borehole may be quite large even at small flow rates of water. During actual field implementation the injected air, if not released completely from the rise side holes, may cause troubles by way of creating potholes on the surface. The pumped-slurry technique has shown its capability of filling a relatively larger area at faster rate, especially when high-volume, low-pressure method was selected. But simple gravity filling was also found to be equally effective method as slurry pumping, especially when flow rates were high. In the second and third method discussed above, examination of variations of injection pressure was also done and its relation with physical phenomenon was also attempted. Some empirical relationships were also developed using multivariate regression with a view to help the practicing engineers.

• 한국지구물리탐사학회:학술대회논문집
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• 2006.06a
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• pp.239-244
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• 2006

Borehole radar reflection surveys were carried out in the horizontal borehole to detect EDZ while constructing the tunnel for the research facility of the nuclear waste disposal in Korea. The horizontal borehole has been bored at a length of 35 m from shelter to be parallel with the tunnel which would be planed. While the tunnel has been constructing with the explosive excavation, the borehole radar reflection surveys carried out 5 times with the interval of 2 or 4 days for monitoring EDZ. The most typical change of the reflection event resulted from the face of the wall of tunnel which had been produced newly by the excavation of the tunnel daily, EDZ has been detected with constructing images of difference between two measurement stages, and also the change of EDZ through the time has been done, which is due to the generation of crack and weakening of the rock strength of the face of the tunnel's wall near previous portion of the face of a blind end of tunnel according to explosive excavation.

• Journal of Ginseng Research
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• v.7 no.2
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• pp.172-192
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• 1983

Light environment and growth of Panax ginseng In habitat and cultivation under natural shade were renewed. Grower's experiences on ginseng stand In relation to light environment were assessed. Change of shading method and grower's concepts on light requirement of ginseng plant in Korea, Manchuria and Japan was counted. Growth of wild ginseng was better under rich light. Optimum crown density index appeared to be 0.7 In natural habitat and 0.4 to 0.7 for the cultivation in forest. Change of light Intensity in forest was greatest in May and reached near to constant value (from 40% to 3% for broad leaf deciduous forest and loom 4% to 2% for pine forest). Insufficient light condition induced long and thin stem, poor flowering and seed bearing, and sequent dormancy. Relation between light and ginseng strand was not clear but light Interception with cool weather was effective. Topography and orientation of bed have been deeply considered for light environment. Panel or bark of won were used for shading in deep forest manly In Manchuria while reed blind and straw thatch were used in Korea. Kinds and number of shades material and seasonal or daily schedule have been simplified probably by labor pressure due to eulargement of plantation. Post height has been greater while width of roof, bed and ditch has changed lisle. Scientific survey in the past omitted important light control methods (complete light hardening etc) which has been practiced in specific areas. The concept and technique of light control in the past in Korea were delicate and intensive including the control of temperature and moisture. For the application of old concept in modem cultivation precise Investigation of the technique including the measurement of light, temperature and moisture is needed.

• Journal of Ginseng Research
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• v.31 no.1
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• pp.34-43
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• 2007

Background: Previous research has suggested that single doses of a standardised Panax ginseng extract can decrease fasted blood-glucose levels and modulate cognitive performance in healthy young volunteers. The latter has generally been seen in terms of improved secondary memory performance. However, both the cognitive effects of chronic administration of ginseng and the potential modulation of working memory have received comparatively little research attention. Aims: The current double-blind, placebo-controlled, balanced cross-over study investigated the effects of 8-weeks administration of Korean ginseng extract (200 mg) on cognitive performance, gluco-regulatory parameters and ratings of subjective mood and 'quality of life'. Methods: 'Eighteen healthy young participants were assessed pre-dose and 3 hours post-dose on the mornings of Day 1, Day 29 and Day 57 of 8 week treatment regimens of both placebo and ginseng. A four-week placebo wash-out separated the treatment phases. Each assessment included the Cognitive Drug Research battery, computerised working memory tasks, and Bond-Lader mood scales. The WHO Quality of Life scale (WHOQOL-BREF) was completed once per visit. Gluco-regulatory parameters were assessed with assays of blood glucose, insulin and HbA1c. Results: Data from the 16 participants that completed the study showed that there were no significant, acute treatment related differences on Day 1 of treatment, or in gluco-regulatory parameters throughout the study. However, time related performance improvements were evident following chronic administration of ginseng on the '3-Back' and 'Corsi-block' computerised working memory tasks. Ginseng was also associated with an improved score on the 'social relations' subscale of the WHOQOL-100, and a significant shift on the 'calm' factor of the Bond-Lader mood scales (from calm/relaxed towards excited/tense). Conclusion: The results of the current study suggest that Korean ginseng extract can modulate working memory performance and subjective ratings of 'quality of life' and mood. Replication with a larger sample size may further elucidate the actions of this product.