• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2012년도 춘계학술발표회 논문집
• /
• pp.324-325
• /
• 2012

다이아몬드 마이크로 블레이드의 절삭 효율을 향상시키고 소결 공정 중 윤활제의 유동성과 젖음성이 다이아몬드 마이크로 블레이드의 물성에 미치는 영향을 연구하기 위해 Cu/Sn 금속 결합재에 표면을 부식시킨 $WS_2$와 부식을 시키지 않은 $WS_2$ 윤활제를 각각 동일한 체적 분율로 첨가하였다. 윤활제의 표면 개질에 따른 마이크로 블레이드 결합재의 내마모성과 굽힘 강도 시험을 행하였고, 실착 절삭 시험을 위한 마이크로 블레이드 시편을 제작하여 수명 및 효율을 평가하였다. Cu/Sn 금속 결합재 파면에서의 $WS_2$ 입자 방향 분석을 통해 표면 개질 과정을 거친 $WS_2$가 압축소결 공정 중 압축 방향에 수직하게 위치하려는 경향이 크게 나타났으며, 이는 소결체의 강도와 경도를 향상시켰다. 마이크로 블레이드의 절삭 효율 및 수명을 평가하기 위한 실착 절삭 시험 결과, 윤활제 표면 부식처리는 처리하지 않은 경우에 비하여 절삭성능은 비슷하게 관찰되었으나 결합재와의 계면 결함을 줄이므로써 블레이드의 수명을 연장시킬 수 있었다.

• International Journal of Oral Biology
• /
• 제46권1호
• /
• pp.45-50
• /
• 2021

This study evaluated the antimicrobial activity of Endoseal TCS, an mineral trioxide aggregate-based root canal sealer, mixed with water-soluble mangostin derivatives (WsMD) of Garcinia mangostana L. (mangosteen) ethanol extract against Enterococcus faecalis and Staphylococcus aureus. The antibacterial activity of Endoseal TCS mixed with WsMD against three strains of E. faecalis and three strains of S. aureus was performed using agar diffusion test. The data showed that Endoseal TCS mixed with 0.115% WsMD had a zone of inhibition of 0.7 ± 0.2-2.4 ± 0.1 mm. The results suggest that Endoseal TCS mixed with WsMD of Garcinia mangostana L. ethanol extract is useful as a root canal sealer with antibacterial activity against E. faecalis and S. aureus.

• Applied Microscopy
• /
• 제50권
• /
• pp.27.1-27.6
• /
• 2020

Transition metal dichalcogenides (TMD), which is composed of a transition metal atom and chalcogen ion atoms, usually form vacancies based on the knock-on threshold of each atom. In particular, when electron beam is irradiated on a monolayer TMD such as MoS₂ and WS₂, S vacancies are formed preferentially, and they are aligned linearly to constitute line defects. And then, a hole is formed at the point where the successively formed line defects collide, and metal clusters are also formed at the edge of the hole. This study reports a process in which the line defects formed in a monolayer WS₂ sheet expends into holes. Here, the process in which the W cluster, which always occurs at the edge of the formed hole, goes through a uniform intermediate phase is explained based on the line defects and the formation behavior of the hole. Further investigation confirms the atomic structure of the intermediate phase using annular dark field scanning transition electron microscopy (ADF-STEM) and image simulation.

• 한국정보기술응용학회:학술대회논문집
• /
• 한국정보기술응용학회 2004년도 춘계학술대회 디지털 컨버젼스(Digital Convergence)와 경영혁신
• /
• pp.81-81
• /
• 2004

• Journal of Microbiology and Biotechnology
• /
• 제27권4호
• /
• pp.844-855
• /
• 2017

Phosphate-solubilizing bacteria (PSB) have the ability to dissolve insoluble phosphate and enhance soil fertility. However, the growth and mineral phosphate solubilization of PSB could be affected by exogenous soluble phosphate and the mechanism has not been fully understood. In the present study, the growth and mineral phosphate-solubilizing characteristics of PSB strain Burkholderia multivorans WS-FJ9 were investigated at six levels of exogenous soluble phosphate (0, 0.5, 1, 5, 10, and 20 mM). The WS-FJ9 strain showed better growth at high levels of soluble phosphate. The phosphate-solubilizing activity of WS-FJ9 was reduced as the soluble phosphate concentration increased, as well as the production of pyruvic acid. Transcriptome profiling of WS-FJ9 at three levels of exogenous soluble phosphate (0, 5, and 20 mM) identified 446 differentially expressed genes, among which 44 genes were continuously up-regulated when soluble phosphate concentration was increased and 81 genes were continuously down-regulated. Some genes related to cell growth were continuously up-regulated, which would account for the better growth of WS-FJ9 at high levels of soluble phosphate. Genes involved in glucose metabolism, including glycerate kinase, 2-oxoglutarate dehydrogenase, and sugar ABC-type transporter, were continuously down-regulated, which indicates that metabolic channeling of glucose towards the phosphorylative pathway was negatively regulated by soluble phosphate. These findings represent an important first step in understanding the molecular mechanisms of soluble phosphate effects on the growth and mineral phosphate solubilization of PSB.

• 대한기계학회논문집A
• /
• 제23권6호
• /
• pp.931-942
• /
• 1999

This paper develops a 3 DOF vehicle model which includes lateral, roll and yaw motion to study a 4WS vehicle. The model is used for the simulation of a 4WS vehicle behavior, and to derive a control algorithm for rear wheel steering. This paper uses a feedforward plus feedback control scheme to compute a rear wheel steering angle. The feedforward control scheme for computing the first rear wheel steering angle uses a gain which is acquired by multiplying a proper value on a gain to maintain a zero sideslip angle. The feedback control scheme for computing the second rear wheel steering angle uses fuzzy logic and model following control scheme. A linear 2 DOF model is used as a reference model for model following control, and is derived from the developed 3 DOF model by neglecting sprung mass roll motion. A reference state variable is yaw rate, and is computed using the linear 2 DOF model. J-turn and lane change maneuver simulation are performed to show the effectiveness of the developed control scheme. The simulation results show that the 4WS vehicle with the developed control scheme has much better performance in yaw rate, lateral acceleration, roll angle, and sideslip angle than the 2WS vehicle. Also, the results show that the performance of the developed control is close to the one of an optimal control which assumes all states are perfect.

• 동의생리병리학회지
• /
• 제17권6호
• /
• pp.1533-1537
• /
• 2003

This double-blind randomized clinical trial was performed to evaluate the anti-anxiety, anti-stress effect of a modified formula WS-01 consisted with several herbs(Jujubae Fructus. Longanae Arillus. Poria Cocos) and germinated rice. The extract of the formula was administered (p.o) to 24 students and placebo was to 23 students for 4 weeks. STAI-KYZ(Hahn. Hakjisa), ABR2000(Meridian, Korea), CBC, LFT, U/A were checked before and after the administration period. There was no difference between the STAI score of WS-01 and that of placebo group in first test. But the STAI state anxiety score was 5.33±7.33 reduced in WS-01 group and it was 0.52±6.42 increased in placebo group in second test. this result was significant stastically. 10 students in WS-01 group showed improving result, but only 1 student in placebo group showed improving result of ABR2000 test. The result of ABR2000 was analyzed with curve 2, Regulation 2, and graph 1,2,3, because those reflect central nerve system and stressful condition of the body. There was no significant result in first and second CBC, LFT, Urine test. The results of this clinical study suggest that WS-01 has anti-anxiety, anti-stress effect, and it could be applied to various conditions or disorders related with anxiety and stress.

• Asian-Australasian Journal of Animal Sciences
• /
• 제24권9호
• /
• pp.1243-1248
• /
• 2011

The aim of this study was to determine the usefulness of vegetable wastes as silage for ruminants. Varying amounts of wheat straw (WS), wheat bran (WB) and salt (S) were combined with minced vegetable wastes (VW) during ensilage. Seven different ingredient combinations were investigated viz: 100% VW (Group I, control), 90% VW+9% WS+1% S (Group II), 80% VW+15% WS+4% WB+1% S (Group III), 70% VW+20% WS+9% WB+1% S (Group IV), 90% VW+9% WB+1% S (Group V), 80% VW+15% WB+4% WS+1% S (Group VI) and 70% VW+20% WB+9% WS+1% S (Group VII). The inclusion of straw and bran increased (p<0.01) the DM content of silage. The highest contents of the pure silage were CP (p<0.001), EE (p<0.01) and NFE (p<0.05). NDF contents of VW silage and group V were significantly lower and especially the VW silage was found to have the lowest ADL content (p<0.01). The in vitro ME values of VW silage and bran added silage were higher than other groups (p<0.01). pH, lactic acid and acetic acid values of silage groups were changed between 4.09-4.20, 2.43-3.46% and 0.60-0.86%, respectively. In conclusion, different mixtures of VW have a high ensilage capacity and can serve as an alternative roughage source for ruminants. The addition of 9% bran significantly improved the silage in view of both dry matter content and nutritive value.

• 한국작물학회지
• /
• 제31권1호
• /
• pp.62-67
• /
• 1986

수확 후 3주와 8주에 맥주보리 49개 품종의 발아세, 발아율 및 수감수성의 품종간 차이를 검토하고자 실험한 결과를 요약하면 다음과 같다. 1. 수확 후 3주에 발아상의 물량 증가에 따른 발아세, 발아율, PI치와 수감수성의 차이는 컸으나 8주에는 그 차이가 적어서 휴비성이 발아세와 발아율을 저하시켰다. 2. 발아세는 휴비성이 소거된 8주에는 전 공시 품종이 극히 양호하였으며, CI 12062와 CI 15631등의 수감수성이 다소 커서 광범위한 육종재료를 교배에 이용할 경우 수감수성의 검정이 필요할 것으로 본다. 3. 수감수성은 저장기간에 관계없이 물 8ml 발아세, 발아율, PI치와 상관이 매우 높았으나 물 4ml에서는 상관관계가 없었다. 4. 저장기간, 품종 및 곡립의 풍만도에 따라서 발아세와 수감수성의 차이가 있으므로 등숙이 양호한 품종의 육성과 등숙향상을 위한 재배법이 연구되어야 할 것으로 생각된다.

• 대한장애인치과학회지
• /
• 제7권1호
• /
• pp.21-24
• /
• 2011

11세 여환이 저작시 불편감을 주소로 내원하여 임상 구강 검사 결과 하악 우측 구치부의 scissor bite이 관찰되었다. 내원 당시 환아는 치과 치료에 대한 두려움과 거부감을 나 타냈고 이에 1년 동안 정기 검진을 하여 환자와의 신뢰관계를 형성 후 교정치료가 가능하였다. Williams Syndrome 환자의 경우 사교적이며 친밀한 성격임에도 치과종사자나 치과 치료에 대한 두려움을 가질 수 있어 치료를 시작하기 전 환자와 치과 종사자간의 관계 형성을 통한 신뢰를 획득함으로 더 나은 질의 치료를 시행할 수 있을 것이다.