• Journal of Life Science
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• v.12 no.6
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• pp.821-834
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• 2002

In order to measure the inter- and intraspecific genetic divergences within the genus Alexandrium, the variations within the internal transcribed spacer (ITS1 and ITS2) regions and 5.85 ribosomal RNA gene of eight Alexandrium species were examined for 33 strains from diverse geographical locations by direct sequencing. Five isolates of A. tamarense (AT-2, AT-6, AT-10, AT-A and AT-B) from Jinhae Bay, Korea were found to be completely identical to a Japanese strain OFX151-A. The length of the amplified ITSI-5.85-ITS2 region varied from 481 nucleotides (in A. margalefi) to 528 nucleotides (in A. affine CU1-1). ITS1 and ITS2 nucleotide lengths were negatively correlated, whereas a positive correlation was found between their G＋C content. The degree of sequence divergence ranged from 0.3% (1 bp) to a maximum of 53% (305 Up). Pairwise sequence comparisons revealed a small degree of divergence between A. tamarense and A. Pundyense isolates (1.2 - 2.3% ＝ 6-12 bp), but a high degree of divergence between A. tamarense and A. catenella (19.8% ＝ 102 bp), and between A. catenella and A. Pundyense (19.7%). Although most nodes were weakly supported by bootstrap values, some types tend to form independent molecular groups. A. catenella isolates also formed an independent molecular sub-group, with relaticula strong bootstrap values (94% or 85% and 79% or 98%, respectively in PAUP and NJ trees). Interestingly, A. cohorticula and A. frateculus always clustered within the same sub-group, this result being supported by strong bootstrap values. Our results indicate that the ITS regions provide useful informations on hierarchical population genetic structure and a high phylogenetic resolution in intraspecific and interspecific Alexandrium population.

• Korean Journal of Medicinal Crop Science
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• v.10 no.3
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• pp.185-193
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• 2002

This study was done to accept basic data on chemical components in rhizome of native Polygonatum species in Korea. In mineral contents of their rhizome, total nitrogen, potassium, calcium, magnesium and sodium concentration were higher in Polygonatum inflatum, P. humile and P. odoratum var. pluriflorum 1 than the other species in all the sampling dates. P. odoratum var. pluriflorum 1, P. odoratum var. pluriflorum 2 and P. inflatum showed relatively higher iron and mananese contents but P. odoratum var. pluriflorum 1 and P. stenophyllum did in copper content on November 20. Total sugar was acculated in later growth stages, although P. stenophyllum had the highest content but P. lasianthum var. coreanum had the lowest in all the sampling dates. Protein content was the highest in P. lasianthum var. coreanum but the lowest in P. stenophyllum in all the sampling dates. The major amino acids in their rhizomes were arginine followed by glutamic acid, and total and essential amino acid content were abundant in P. lasianthum var. coreanum and P. humile.

• The Journal of Korean Medicine
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• v.26 no.2 s.62
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• pp.217-230
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• 2005

Objectives: Chungpaesagan-tang (CPSGT), which is frequently used for treating patients of cerebrovascular disease, has not been reported by clinical doctors concerning the effect of neuronal aptosis caused by brain ischemia. To study the effect of CPSGT on focal cerebral ischemia in normal and diabetic rats and SHR, focal cerebral ischemia was induced by transient MCAO, and after onset CPSGT was administrated. Methods: Rats (Sprague-Dawley) were divided into four groups: sham-operated group, MCA-occluded group, CPSGT­administrated group after MCA occlusion, and normal group. The MCA was occluded by intraluminal method. CPSGT was administrated orally twice (l and 4 hours) after middle cerebral artery occlusion. All groups were sacrificed at 24 hours after the surgery. The brain tissue Was stained with $2\%$ triphenyl tetrazolium chloride (TTC) or $1\%$ cresyl violet solution, to examine effect of CPSGT on ischemic brain tissue. The blood samples were obtained from the heart.~. Tumor necrosis $factor-\alpha$ level and interleukin-6 level of serum was measured from sera using enzyme-linked immunoabsorbent assay (ELISA). Then changes of immunohistochemical expression of $TNF-\alpha$ in ischemic damaged areas were observed. Results: In NC+MCAO+CP and DM+MCAO+CP, CPSGT significantly (p<0.01) decreased the number of neuron cells compared to the control group. CPSGT markedly reduced (p<0.01) the infarct size of the forebrain in distance from the interaural line on cerebral ischemia in diabetic rats. CPSGT significantly reduced the $TNF-\alpha$ expression in penumbra region of damaged hemisphere in diabetic rats. Conclusions: CPSGT had a protective effect on cerebral ischemia in SD rats, especially in diabetic rats compared with normal SD rats.

• The Journal of Engineering Geology
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• v.26 no.3
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• pp.361-370
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• 2016

This study was performed in order to evaluate the efficiency of groundwater well installed in alluvial aquifer that has filter layers, using laboratory experiment. We manufactured test equipment that can simulate dual filter layer and single filter layer and evaluated the initial volume of water intake, pumping efficiency, and long term stability using the experiment and analysis. In an early stage within 60 minutes, the case that took the dual filter showed an increase of 19.4 % in the initial volume of water intake compared to the case without it. It was found that after 24 hours of the test, the well installed with the dual filter showed higher than 68.9% compared to the well with single filter. It was calculated that it took 1.35 days to reach the point corresponding to the half of the water intake in case of single filter while it took 38.66 days to do so in case of dual filter. Therefore, it is highly recommended that the well with dual filter is much more favorable in the long term stability.

• Tribology and Lubricants
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• v.34 no.3
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• pp.84-92
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• 2018

Bearings are essential for reducing vibration and wear, in order to achieve high durability and increase longevity. White metal treatment of tilting pads via centrifugal casting method has the possibility of increasing durability. However, this manufacturing method has drawbacks such as long processing time, high defect rate, and harmful health effects. Laser cladding deposition technique is a powerful method that can address these issues by decreasing the processing time and providing good adhesion. In this study, we suggest optimum conditions for laser cladding deposition that can be used in industrial applications. We deposited a soft white metal layer on SCM440 that is primarily used in shafts to minimize wear of bearing pads. During the laser deposition process, we controlled factors such as laser power, powder feed rate, and laser head speed to determine the optimum conditions. In addition, we measured the hardness using micro Vickers, and performed field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and friction tests to investigate the mechanical properties and surface characteristics for different parameters. Based on the experimental results, we suggest that laser power, powder feed rate, and laser head speed of 1.3 kW, 2.5 rpm, and 10 mm/s, respectively, constitute the optimum conditions for producing white metals using laser cladding.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.112-112
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• 1999

고분자 표면에 MeV급 이온을 주입하게 되면 화학적, 광학적, 물리적, 전기적 특성 등 기존의 재래식 공정으로는 불가능한 다양한 특성변화가 일어나게 된다. 본 실험에서는 이온 조사에 따른 micro-hardness의 변화에 중점을 두어 관찰하였다. 수 MeV로 가속시킨 Cl과 C 이온을 Kapton, Teflon, PMMA에 조사량을 바꾸어가며 조사하였다. 이때 조사 전후 고분자 시료의 표면 경도는 depth-sensing nanoindentation technique (Nano Indenter II, USA)을 이용하여 측정하였다. 측정깊이는 극표면 효과와 기측효과의 영향을 무시할 수 없는 100nm로 결정하였다. 또한 이와 같은 경도변화를 규명하기 위하여 각각의 시료에 대해 FTIR, Raman, UV-VIS, RBS, XPS 스펙트럼을 측정하였으며, 조사중에 발생되는 가스상 분자들을 RGA를 이용하여 측정하였다. 1 MeV Cl 이온을 Kato에 4x1015ions/cm2 조사하면 경도가 0.35 GPa에서 7.1GPa로 약 20배 정도 증가하게 되며, 이 경도는 stainless steel 경도 2~3 GPa, martensite steel 8~12와 비교하여 보면 상당히 높은 수준임을 알 수 있다. Teflon과 PMMA 시료의 경우 1MeV Cl 이온 4X1015ions/cm2를 조사시키면 각각 경도가 0.31GPa에서 4.1a, 0.30 GPa에서 3.9GPa로 변화하였으며 Kapton에 비하여 상대적으로 경도의 변화가 적음을 알 수 있었다. 이온 주입된 Kapton의 경우 FT-IR측정에 의하여 이온 조사량이 증가함에 따라 C=O 진동, 이미드그룹의 CONH, tertiary amine의 C-N 흡수 피크가 감소되며, 1X1014ions/cm2 이상의 양이 조사되어야 개질변화가 일어남을 알 수 있었다. XPS 측정 결과 Kapton에 조사되는 이온양이 증가할수록 C=O, C-O 및 C-N의 탄소는 감소하고 페닐고리 탄소가 증가함을 알 수 있었다. 또한 이온 조사 중 측정한 RGA에서도 CO 가스가 대량 방출되는 현상을 관찰하였으며 FTIR 및 XPS에서의 C=O 결합의 감소와도 일치하였다. RBS에 의한 CNO 원소의 변화에서도 다른 원소보다 O의 감소가 현저하게 나타남을 확인하였다. UV-VIS 측정을 통해 조사 이온량에 따라 에너지 준위가 변동하여 흡수스펙트럼이 장파장으로 확대됨을 알 수 있었으며, 이는 공액 2중 결합의 형성에 의한 $\pi$-전자 및 기타 결함에 기인한다. PMMA 및 Teflon의 경우 FTIR 측정에 의하여 이온 조사됨에 따라 function group 들의 peak가 세기가 감소되면서 완만해지는 경향을 보이며 원래의 구조를 상실하게 된다. PMMA와 Teflon은 이온 조사가 되면 가교형서보다는 사슬절단이 주로 일어나므로 가교형성이 잘 일어나는 Kapton보다는 상대적으로 경도의 증가가 적음을 알 수 있었다.

• Journal of the Korean Geosynthetics Society
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• v.10 no.4
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• pp.37-47
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• 2011

This paper describes the stability evaluation of reinforced earth wall with steel framed-facing based on field test. The reinforced earth wall with steel framed-facing is composed of wall facing, reinforcement and backfill soil. The wall facing is assembled by steel frames and the aggregates are filled in that. The reinforcement is steel strip type based on bearing resistance. Field test is conducted to evaluate for two separate sections and the measurement is conducted according to construction elapsed time of structure for earth pressure, horizontal displacement of wall facing and reinforcement strain. The evaluation results show that the measured earth pressure is less than theoretical earth pressure due to dispersion effect of earth pressure by the applied reinforcement. Also, the horizontal displacement of wall facing satisfied a empirical criteria and the measured strain of reinforcement had nearly no effect on stability of structure. Therefore, the reinforced earth wall with steel framed-facing has a structural stability and it can be commonly used in field.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.9
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• pp.1083-1095
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• 1999

최근 처리기와 입출력 시스템의 속도 차이가 점점 커짐에 따라 버퍼 캐쉬의 효율적인 관리가 더욱 중요해지고 있다. 버퍼 캐쉬는 블록 교체 정책과 선반입 정책에 의해 관리되며, 각 정책은 버퍼 캐쉬에서 블록의 가치 즉 어떤 블록이 더 가까운 미래에 참조될 것인가를 결정해야 한다. 블록의 가치는 응용들의 블록 참조 패턴의 특성에 기반하며, 블록 참조 패턴의 특성에 대한 정확한 분석은 올바른 결정을 가능하게 하여 버퍼 캐쉬의 효율을 높일 수 있다. 본 논문은 각 응용들의 블록 참조 패턴에 대한 특성을 분석하고 이를 자동으로 발견하는 기법을 제안한다. 제안된 기법은 블록의 속성과 미래 참조 거리간의 관계를 이용해 블록 참조 패턴을 발견한다. 이 기법은 2 단계 파이프라인 방법을 이용하여 온라인으로 참조 패턴을 발견할 수 있으며, 참조 패턴의 변화가 발생하면 이를 인식할 수 있다. 본 논문에서는 8개의 실제 응용 트레이스를 이용해 블록 참조 패턴의 발견을 실험하였으며, 제안된 기법이 각 응용의 블록 참조 패턴을 정확히 발견함을 확인하였다. 그리고 발견된 참조 패턴 정보를 블록 교체 정책에 적용해 보았으며, 실험 결과 기존의 대표적인 블록 교체 정책인 LRU에 비해 최대 57%까지 디스크 입출력 횟수를 줄일 수 있었다.Abstract As the speed gap between processors and disks continues to increase, the role of the buffer cache located in main memory is becoming increasingly important. The buffer cache is managed by block replacement policies and prefetching policies and each policy should decide the value of block, that is which block will be accessed in the near future. The value of block is based on the characteristics of block reference patterns of applications, hence accurate characterization of block reference patterns may improve the performance of the buffer cache. In this paper, we study the characteristics of block reference behavior of applications and propose a scheme that automatically detects the block reference patterns. The detection is made by associating block attributes of a block with the forward distance of the block. With the periodic detection using a two-stage pipeline technique, the scheme can make on-line detection of block reference patterns and monitor the changes of block reference patterns. We measured the detection capability of the proposed scheme using 8 real workload traces and found that the scheme accurately detects the block reference patterns of applications. Also, we apply the detected block reference patterns into the block replacement policy and show that replacement policies appropriate for the detected block reference patterns decreases the number of DISK I/Os by up to 57%, compared with the traditional LRU policy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1485-1489
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• 2005

The dropwort was fermented by steeping with brown sugar, fructose syrup or oligosaccharide at room temperature for 2 month, and then stored at cold room for 6 months. The dropwort extracts prepared with three different sugars showed more than $50^{\circ}$Brix, below pH 4.0 and about $0.7\%$ titratable acidity. The dropwort extract with brown sugar showed $1.6{\times}10^6$ viable cell counts and $21.2\%$ reducing sugar. Formation of $CO_2$ gas was superior to the dropwort fermented with brown sugar or oligosaccharide. The dropwort extract with fructose syrup indicated $9.0{\times}10^3$ viable cell counts and $50.1\%$ reducing sugar. Microorganism present in fermented dropwort extract was effectively pasteurized by the addition of $3\%$ citric acid and heat-treatment at $85^{\circ}C$ for 15 min, resulting in the less production of $CO_2$ gas. The dropwort extracts prepared with brownsugar, fructose syrup or oligosaccharide was suitable for the standardization that required for plant extract in Korea Food Codex.

• Journal of Oriental Neuropsychiatry
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• v.15 no.1
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• pp.175-185
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• 2004

Objective : For investigating correlation among diagnostic types, MMPI results and Sasang constitutions, in out-patients of Oriental Neuropsychiatry. Method: We got the following result by comparing the out-patients' MMPI and QSCCII from 2000/12/1 to 2001/12/30 at Sanbon Hospital of Oriental Medicine, Wonkwang University. Result and Conclusion: 1. A specific character of population for study's objects was that female (128, 68.4%) was twice bigger that the male(59, 31.6%). And their education levels were 52 of college graduate (27.8%), 40 of high school graduate (21.4%), and 14 of middle school graduate (14 %). A distribution of the occupation, there are 62 of labors (33.2%), 62 of white collars (33.2%), 30 of sales (16%), 16 of students (8.6%). Their marrige statuses were 144 of married (77%), 31 of single (16.6%), 4 of divorced (2.1%), and 1 of bereavement (0.5%). 2. In the physical constitutions there were 70 of Soeumin(37.4%), 56 of Soyangin(29.9%) 55 of Taeumin (29.4%), 6 of others (3.2%). A differentiation with their diagnosis, there were 55 of palpitations (29.4%), 45 of depression (24.1%), 18 of women's diseases (9.6%), 14 of insomnia (7.5%), 13 of headache (7%), 8 of pain (4.3%), 8 of hwabyung (4.3%), 7 of psychosis (3.7%), 4 of dizziness (2.1%), and 15 of others(8%). 3. A result of groupling MMPI, we could classify into 4 different groups. Group 1 is a profile of trasition in a neurosis. Group 2 is a proflie of a mental disease. Group 3 is a proflie of $'{\wedge}'$ type neurosis. And group 4 has normal profile. 4. Regarding each group with physical constitution and a distribution of diagnosis, Group 1 is found out 36.4 % of Soeumin, 34.10 % of palpitations. And group 2 showed 43.6% of Soyangin, 25.6% of depression. Group 3 showed 46.4% of Soyangin, 31.90% of palpitations. Group 4 showed the most in 34.3% of Soyangin, and 31.40% of palpitations 5. A result of the study using Chi-square test is that there is no correlation between the 4 different groups and the Sasang physical constitution.