VHDL을 이용한 MAP의 링크계층의 구현

이상호,신동렬 成均館大學校 科學技術硏究所 1997 論文集 Vol.48 No.2

Computer-integrated automation in manufacturing systems largely depends on local-area networks (LAN's) for information exchange between devices such as computers, PLCs, NCs, and robots. Timely transfer of messages among such devices are critical for real-time operations. Manufacturing Automation Protocols (MAP) is specially designed to provide rapid and reliable which takes place on the factory floor. The token-bus network has emerged as the standard for LANs in industrial environments due to its stability, reliability, and the availability of a priority scheme. For this reason, MAP has specified the token passing bus control for use in the Medium Access Control(MAC) sublayer and Logical Link Control(LLC) sublayer in the data link layer. In this work, we will implement the token bus control algorithms with VHDL, and MAP protocol with relatively low cost. Much will be emphasized on implementing MAP standard protocol based on MAC and LLC.

다발성 말초신경병증의 조기진단 : 적외선 체열촬영검사와 전류지각역치검사의 조합진단 Combination Diagnosis Using by Digital Infrared Thermogram and Current Perception Threshold

이삼규,김재형,최인성,이소영,한재영,조성렬,김재휴,노성만,정민영,정동진,김현성 全南大醫大 2001 전남의대학술지 Vol.37 No.3

PECVD로 제작한 수소화된 비정질 탄소(a-C:H) 박막의 광학적에너지 갭과 전기전도도

박혁렬,이석호,오동선,홍선화 木浦大學校基礎科學硏究所 1996 基礎科學硏究誌 Vol.14 No.-

Hydrogenated amorphous carbon(a-C:H) films were deposited onto glass or Si-wafer substrate from CH₄ gas by using PECVD(plasma Enhanced Chemical Vapor Deposition) method. The films were deposited at various substrate temperatures and two different position of the substrate. The optical and electrical properties of the deposited films were characterized by measuring such as UV/VIS transmission spectrum, FTIR absorption spectrum and dark electrical conductivity. We found a decreased in deposition rate and optical energy gap as the substrate temperature was increased. The deposition rate was increased for the films deposited at IS(ion-sheath) region than at BP(bulk-plasma) region, while the optical energy gap was increased for the films deposited at BP than at IS region. We obtained a very hard diamond-like-carbon(DLC) films at IS region and in optimal substrate temperature. The films showed a thermally activated conduction with an activation energy of about 0.24 eV above 400 K, while a variable range hopping conduction below about 400 K.

타타늄의 열처리 조건에 따른 동전위 양극분극특성 및 표면 미세구조 변화

주동현,이용렬,정영화,양홍서,박상원,이도재,송호준,박영준 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.2

The corrosion resistance of metallic implants is essential for successful implant osseointegration. Moreover, the implant surface should have appropriate surface roughness for the attachment of the osteoblast and collagen fibrils. When titanium is exposed to air a thermodynamically very stable oxide film is formed at once. This oxide is very thin and yet it protects the metal from corrosion instantaneously. However, the oxide would not be ideal, and it would be supposed that the state of oxide film would be various by the different conditions when it is formed. The objective of this study was to evaluate the electrochemical properties and surface microstructural changes of titanium after passivation treatment or exposure to high heat (in vacuum or in air). ASTM grade 2 commercially pure titanium (Ti) disks of 10㎜ diameter were wet ground and polished with 240 and 600 grit SiC, and then ultrasonically cleaned with distilled water and ethanol. Cleansed as-received samples (As-R group) were passivated with 30% nitric acid solution at 50℃ for 15 minutes to make the Pas group. The Std-V samples were made by treating the Ti disks in vacuum quartz tube (10^-8 Torr) at 530℃ for 40 min for stress relieving, followed by annealing at 700℃ for 90 min, and then slow cooling to room temperature. The Std-A samples undergo identical procedure as the Std-V group except that it is done in air. For 530℃-V samples, Ti disks were heated at 530℃ for 40 minutes and slow cooled to room temperature. The 1000℃-V samples were produced by heating Std-V specimens again at 1000℃ for 2 hr, followed by cooling to room temperature. 530℃-A and 1000℃-A samples were also prepared. Potentiodynamic anodic polarization measurement, SEM, AFM and XRD analysis were performed to evaluate the effects of the various treatments. The difference in the mean values of E_corr between groups showed statistically significant difference (P<0.05), but that of I_corr did not show significance (P>0.05). When Ti surface was passivated there was a shift of corrosion potential (E_corr) in the noble direction and a lower corrosion current density (I_corr) value. Std-A samples showed most noble E_corr value among the tested groups. 530℃-V samples showed more noble E-corr than other tested groups except Std-A group. 1000℃-V samples showed more noble E-corr than those of Std-V sample. In the case of Std-, 530℃- and 1000℃-groups, -A sub-groups showed better corrosion resistant characteristics than -V sub-groups in regard to E-corr and I_corr values. In the SEM observations, the surfaces of the As-R samples showed only scratch line on smooth surface. In Pas samples, thick oxide layer covered the surface under high magnification observation. 530℃-A samples were covered by oxide granules, and Std-A samples had 25~50 nm-thick acicular oxides. The 1000℃-A samples were covered by coarse oxide crystals with a granule diameter of 0.1~0.6 μm having a gross appearance of milky white color, which was identified by XRD as a rutile. On the other hand, 1000℃-V samples showed an Widmansta¨tten structrue of which the orientation of the lattice is formed along crystallographic planes of the parent crystals. On the AFM observation, 530℃-A samples showed RMS roughness of 79.38 nm which is 5 times rougher than those of the As-R samples. Std-A sample had a roughness of 330.47 nm which is about 20-times rougher than that of the As-R sample. 1000℃-A samples were covered by coarse granular oxides and the roughness were about 0.56 μm. Vacuum sub-group samples showed a more smooth surface than air sub-group samples, and the oxide film was more dense. Due to variability of the surface treatment and heat treatment conditions, the process of the oxide formation seems to be affected thereby making the corrosion properties and surface micro-morphology different. However, more various electrochemical analysis together with surface analysis, and an investigation for the effects of those on the osteoblast cell adhesion and calcium phosphate apposition are needed for the improvement of the osseointegration rates of the titanium implants.

PECVD로 제작한 수소화된 비정질 탄소(a-C:H) 박막의 화학결합 구조에 관한 연구

노지연,이석호,오동선,박혁렬,김영산 木浦大學校基礎科學硏究所 1997 基礎科學硏究誌 Vol.15 No.-

Hydrogenated amorphous carbon(a-C:H) films were prepared by PECVD(Plasma enhanced-chemical vapor deposition) method. The films were characterized using various spectroscopic measurements such as Raman scattering, FTIR(Fourier transform infrared) absorption spectroscopy. FRIR absorption reflects only the optically active hydrogen in the a-C:H and, using it together with Raman spectroscopy. The spectral analysis indicated that changes in Raman spectroscopy intensity occurring with increasing substrate temperature 50℃~300℃ were determined to be caused by changes in optically resonant components in the films. Furthermore, a significant correlation was the two crystalline forms of carbon-graphite and -diamond consist of sp² and sp³ bonds, respectively. Significant changes in chemical bonding(sp²/sp³) and micro-structure of hydrogenated amorphous carbon thin films occur as the substrate temperature varies from 50 to 300℃ during.

생활하수슬러지가 토양 화학성 및 장미의 생육에 미치는 영향

최정,이동훈,박만,최충렬,김광섭 한국환경농학회 2002 한국환경농학회지 Vol.21 No.2

생활하수슬러지를 장미 재배지에 토양 개량제로서 시용량을 달리하여 첨가하고 장미의 생육상, 토양 및 식물체중 중금속의 함량에 미치는 영향을 조사하였다. 장미 재배지에 하수슬러지를 사용하면 시용량이 증가함에 따라 신장과 비대생장이 증가했으며 주당 꽃송이도 많아 생육이 양호한 것으로 나타났다. 토양 중 중금속 함량은 시용량의 증가에 따라 일정한 경향은 없었으며 식물체에 의한 대부분의 무기성부 흡수량은 하수 슬러지의 시용량에 따라 증가하는 것으로 나타났다. 결과적으로 생활 하수 슬러지는 유해물질의 농도가 낮으면 경작지에 처리하여도 무관할 것으로 판단된다. This study was conducted to find out the effect of municipal sewage sludge on the growth and heavy metal content of rose and soil chemical properties. Municipal sewage sludge was applied to soil at rate of 0, 3, 5, 10 and 15 ton/10a, the plant height, flower number and stem size of rose were found to be increase in the treatments of sewage sludge. Contents of mineral nutrients in rose stem were determined to be higher at municipal sewage sludge application plots than those of no application. But, there were not any significant increases of heavy metal contents in soil and rose stem with the sludge applications. From the results of this study, it is apparent that the application of municipal sewage sludge would not increase available heavy metals in soil.

인공방광대치술을 받은 환자에서의 대사 산증 발생

김새인,이동현,김광현,류동열,김승정,강덕희,최규복,이신아 이화여자대학교 의과학연구소 2015 EMJ (Ewha medical journal) Vol.38 No.3

Objectives: Metabolic acidosis frequently develops in patients after neobladder reconstruction. However, the incidence of metabolic acidosis in patients with neobladder and the factors associated with the development of metabolic acidosis have not been well elucidated. We aimed to investigate the incidence and the potential predictors for the development of metabolic acidosis after neobladder reconstruction with intestinal segment. Methods: We included patients who underwent neobladder reconstruction using intestinal segment at Ewha Womans University Mokdong Hospital between January 1, 2005 and December 31, 2014. A subgroup of patients according to the time of metabolic acidosis occurrence was further analyzed in order to characterize predictors for metabolic acidosis. Results: Metabolic acidosis was encountered in 79.4% of patients with neobladder during follow up period. When patients were divided into 2 groups according to anion gap (AG), total CO2 (18.9±2.1 mEq/L vs. 20.0±1.3 mEq/L, P=0.001) and chloride (106.6±4.9 mE/L vs. 109.4±3.6 mEq/L, P<0.001) were significant different between groups with AG>12 and AG≤12. Furthermore, when patients were divided into 3 groups; patients with metabolic acidosis at postoperative day (POD) 1; from POD 2 to 14 days; after 14 days, there was significant difference among those subgroups. Conclusion: Our study showed the rate of metabolic acidosis in patients underwent neobladder reconstruction and the difference between patients with metabolic acidosis and those without metabolic acidosis for the first time in Korea. In the future, well designed prospective study will be needed to prevent metabolic acidosis after neobladder reconstruction.

정보통신 서비스 산업에서의 신규투자 및 인수결정요인

박영렬,김동재,이정훈 연세대학교 경영연구소 2001 연세경영연구 Vol.38 No.1

본 연구는 세계 정보통신 서비스 기업의 해외시장 진입에 있어서 신규투자와 인수의 선택에 영향을 미치는 결정요인을 거래비용이론과 인수합병이론을 이용하여 실증적으로 분석하였다. 본 연구결과에 의하면 무선통신 사업분야에 진출할 경우, 그리고 잠재성장률이 높은 시장에 진출할 경우 정보통신 기업은 인수를 선호하는 것으로 나타났다. 그러나 정보통신 기업의 규모, 기술적 지식, 해외 사업경험 및 진입시장의 과거성장률은 신규투자와 인수 결정에 영향을 미치지 않는 것으로 분석되었다.

대구시의 지역별 생활쓰레기 성상 및 특성

노숙현,이동훈,최충렬,박만,박병윤,최정 한국환경과학회 2003 한국환경과학회지 Vol.12 No.4

This study was conducted to provide the basic information to know reasonable method for the removal and treatment of municipal solid wastes(MSWs). MSWs four different sources(apartment, residence, commerce, office/industry) in Daegu city were collected, and bulk density, physical composition, moisture, combustible, ash, elements and heating values were investigated. The values of bulk density were at range of 0.30~0.41ton/㎥. The percentages of foods, papers, vinyls/plastics, textiles, rubbers/leathers, metals and glasses/ceramics of wet muncipal solid wastes from three sources except office/industry were at range of 27.3~46.4&, 21.2~38.4%, 10.3~11.9%, 3.8~5.2%, 0.5~1.7%, 6.9~8.7% and 1.9~2.6% respectively. The percentages of papers, foods, vinyls/plastics, textiles, rubbers/leathers, metals and glasses/ceramics of dry muncipal solid wastes from three sources except office/industry were at range of 21.2~40.4%, 14.2~30.1% 15.2~17.8%, 4.0~6.0%, 0.9~2.8%, 12.2~14.1% and 3.1~3.7% respectively. The moisture contents of foods, woods, textiles and papers in wastes were at range of 65.7~76.2%, 34.6~50.0%, 22.2~44.8 and 30.6~44.4% respectively. The carbon contents of vinyls/plastics, rubbers/leathers, textiles, woods, papers and foods in wastes were at range of 75.88~79.87%, 58.24~70.74%, 45.23~51.63%, 42.29~45.58%, 40.19~48.4% and 25.86~36.25% respectively. The low heating values of foods, papers, woods, textiles, rubbers/leathers and vinyls/plastics by Dulong's law were at range of 178~1,353㎉/㎏, 770~1,660㎉/㎏, 995~1,629㎉/㎏, 2,133~2,432㎉/㎏, 4,200~7,275㎉/㎏ and 6,384~8,722㎉/㎏ respectively, and the high heating values of them were at range of 782~2,056㎉/㎏, 2,459~3,314㎉/㎏, 3,056~3,592㎉/㎏, 4,381~5,087㎉/㎏, 5,005~8,066㎉/㎏ and 10,032~10,739㎉/㎏ respectively.

SAN을 이용한 큐잉모델 해결방법

장경수,신호진,이상호,김병기,신동렬 成均館大學校 科學技術硏究所 2000 論文集 Vol.51 No.2

Queueing analysis, in general., has the intrinsic problem of large state space dimension and complex computation. In fact, the petri net is a graphical and mathematical model. It has been used for the modeling of various applications, in particular, manufacturing systems. It can deal with parallelism, concurrence, deadlock avoidance, and asynchronism. Currently it has been applied to the performance of computer networks and protocol verifications. This paper presents a technique for modeling and analyzing queueing model using stochastic activity networks (SANs). And then some examples are showed for the verification of the technique presented in this paper.