대학순례-코넬대학의 특성과 교육환경

박원규,Park, Won-Gyu 한국대학교육협의회 1990 大學敎育 Vol.45 No.-

조경용 탄성포장의 재료 배합비에 따른 결합력과 탄성분석

박원규,Park, Won-Kyu 한국조경학회 2010 韓國造景學會誌 Vol.38 No.5

탄성포장은 보행자의 만족감이 매우 높아 수요가 지속적으로 증가할 것으로 예상되나, 탄성포장의 재료 배합기준 즉, 합성고무 칩(EPDM chip)과 폴리우레탄 바인더의 적정배합기준이 미비하여 시공 시 많은 시행착오를 겪고 있는 실정이다. 따라서, 본 연구는 조경용 탄성포장의 폴리우레탄 바인더 배합비에 따른 결합력과 반발탄성의 변화를 실험을 통해 분석하고, 이를 바탕으로 적정한 재료배합 비율을 제시하고자 하였으며, 실험결과는 다음과 같다. 인장실험에서는 시료 B와 시료 C가 바인더 배합비율과 인장강도 간에 강한 양의 상관관계가 있는 것으로 나타나, 배합비율이 증가하면 인장강도가 증가한다는 것을 알 수 있다. 경도실험에서는 시료 A,시료 B,시료 C모두 바인더 배합비율과 경도 간에 통계적으로 상관관계가 없는 것으로 나타나, 탄성포장재의 경도는 바인더의 배합비율에 따라 달라지지는 않는 것으로 판단된다. 반발탄성실험에서는 시료 A와 시료 B가 배합비율과 반발탄성 간에 강한 음의 상관관계가 있는 것으로 나타나, 배합비율이 증가하면 반발탄성이 낮아진다는 것을 알 수 있다. 실험결과를 바탕으로 적정배합비율을 분석해 보면 인장강도의 경우, 인장강도의 증가가 둔화되거나 오히려 감소하는 배합비율 포인트는 20%이며, 반발탄성의 경우, 반발탄성이 급격하게 감소하는 배합비율 포인트는 22%이다. 따라서 두가지 요인을 감안할 때, 적정 배합비는 20~22% 사이로 판단된다. 본 연구의 결과는 조경용 탄성포장 시공 시 결합력과 탄성을 제고할 수 있는 재료배합의 지침을 제공할 수 있을 것으로 기대된다. The demand for elastic pavement, providing comfort for pedestrians is expected to increase continuously but the lack of a standard for materials mixing ratio, that is, the optimal mixing ratio between ERDM chip and polyurethane binder, is still in a trial and error stage. This study aimed at recommending an optimal mixing ratio for elastic landscape pavement through a coherence and resilience test depending on ratio. The test result is outlined as follows. In a tensile strength test, samples B and C indicated a close positive relationship between the binder mixing ratio and tensile strength, indicating that the higher the mixing ratio the higher the tensile strength. In a hardness test, none of samples A, B or C indicated a statistical interrelationship between the binder mixing ratio and hardness. That is, the hardness of the elastic pavement material remained unchanged, irrespective of the binder mixing ratio. In a resilience lest, Samples A and B indicated a close negative interrelation between mixing ratio and resilience, indicating that the higher the mixing ratio, the lower the resilience. Upon analyzing the optimal mixing ratio based on test results, an increase in tensile strength began to slow at a 20% mixing ratio, while resilience began to reduce rapidly at 22%, Thus the optimal range for a mixing ration appeared to be 20~22%. The outcome of this study could to provide guidance for improving the elasticity and stability of elastic pavement.

연마방법에 따른 금속의 활택도에 관한 연구 - Atomic Force Microscope를 이용한 -

박원규,우이형,최부병,이성복,Park Won-Kyu,Woo Yi-Hyung,Choi Boo-Byung,Lee Sung-Bok 대한치과보철학회 2003 대한치과보철학회지 Vol.41 No.1

The surface of metals should be as smooth as possible for optimum comfort, oral hygiene, low plaque retention, and resistance to corrosion. In this study five specimens of each precious metal(type III gold alloy, ceramic gold alloy, and Ag-Pd alloy) were divided into five groups according to finishing and polishing procedures : group 1(sandblaster), group 2(group 1+stone), group 3(group 2+brown rubber), group 4(group 3+green rubber), and group 5(group 4+rouge). Six specimens of each non-precious metal(Co-Cr alloy, Ni-Cr alloy, and Co-Cr-Ti alloy) were divided into six groups: group 1(sandblaster), group 2(group 1+hard stone), group 3(group 2+electrolytic polisher), group 4(group 3+brown hard rubber point), group 5(group 4+green hard rubber point), and group 6(group 5+rouge). Considering factors affecting the rate of abrasion, the same dentist applied each finishing and polishing procedure. In addition, the surface roughness of enamel, resin, and porcelain was evaluated. The effect of finishing and polishing procedures on surface roughness of precious and non-precious metals, enamel, resin, and porcelain was evaluated by means of Atomic Force Microscope(AutoProbe CP. Park Scientific Instruments, U.S.A.) that can image the three dimensional surface profile and measure average surface roughness values of each sample at the same time. The obtained results were as follows : 1. According to finishing and polishing procedures, the surface roughness of type III gold alloy, ceramic gold alloy, and Ag-Pd alloy was decreased in the order of group 1, 2, 3, 4, and 5 (P<0.01). 2. According to finishing and polishing procedures. the surface roughness of Co-Cr alloy, Ni-Cr alloy, and Co-Cr-Ti alloy was decreased in the order of group 1, 2, 3, 4, 5, and 6 (p<0.01). 3. There was not statistically significant difference in the surface roughness among three metals of precious metals in group 1 but was significant difference in group 2, 3, 4, and 5 (P<0.05). 4. There was not statistically significant difference in the surface roughness among three metals of non-precious metals in all groups. 5. When the surface roughness of the smoothest surface of each metal, enamel. porcelain, and resin was compared, porcelain was the smoothest and the surface roughness was decreased in the order of Ni-Cr alloy. Co-Cr alloy. Co-Cr-Ti alloy, resin. Ag-Pd alloy, ceramic gold alloy type III gold alloy, and enamel (P<0.01). The results of this study indicate that the finishing and polishing procedures should be carried out in a logical, systematic sequence of steps and the harder non-precious metals may be less resistance to abrasion than are the softer precious metals.

정관운동에 있어서 prostaglandin 의 역할에 관한 연구

박원규,Park, Won-Kyoo 대한약리학회 1983 대한약리학잡지 Vol.19 No.2

Prostaglandin(PG) is ubiquitously distributed in most mammalian tissue and their actions are complicated. Especially in autonomic nervous system, there are evidences indicating that PGs act as neuromodulators i.e., PGs, which are released in the vicinity of autonomic neuroeffector junctions, influence the release and the response of the neurotransmitter. Present study was undertaken to elucidate the interrelationship between $PGF_{2\alpha}$ and adrenergic ${\alpha}_2-receptor$ function in electrical field stimulation induced contractile response of vas deferens in rat. Male rat, weighing 150{\sim}200\;g, was sacrificed and vas deferens was obtained. The isolated vas deferens strip was placed between two platinum electrodes in temperature controlled $(37^{\circ}C)$ muscle chamber containing Tyrode's solution and the electrical field stimulation(EFS) induced contraction was recorded with Grass Polygraph(Model 7) via force displacement transducer (FT .03, Grass). The results are summarized as follows: 1) Electrical field stimulation for 1sec( 1 msec, 40 cps) induced contraction of vas deferens was completely blocked by tetrodotoxin. 2) Bretylium caused marked inhibition of the EFS-induced contraction, hut tyramine and cocaine augmented the contraction. 3) EFS-induced contraction was inhibited or little affected in distal portion of vas deferens by norepinephrine or methoxamine, but the contraction was rather augmented by the ${\alpha}-agonists$ in proximal portion. 4) Clonidine inhibited the EFS-induced contraction proportionally to the concentration in distal portion, which was blocked by yohimbine pretreatment, but in the presence of $PGF_{2\alpha}$ the blockade by yohimbine was reversed. 5) Indomethacin pretreatment reduced the effect of clonidine, but addition of $PGF_{2\alpha}$ after washing-out the indomethacin caused the contraction to the control level. From these results it is suggested that PG synthesis is a necessary step and the PG itself has a permissive role in ${\alpha}_2-adrenoceptor$ action in rat vas deferens.

土地 利用型 農作物 生産性 向上指針

박원규,김진희 ( W . K . Park,J . H . Kim ) 한국농업기계학회 1990 바이오시스템공학 Vol.15 No.2

자기 연마법에 의한 질화 규소계 세라믹 파이프 내면의 경면 연마 특성에 관한 연구

박원규,타케오시무라,Park, Won-Gyu,Shinmura, Takeo 대한기계학회 2001 大韓機械學會論文集A Vol.25 No.1

Results ar presented of a new process for internal precision finishing of slender fine ceramic pipes using a magnetic field generated by a permanent magnets. For finishing the interior surface of a long pipe, a new type of finishing equipment was developed which can be very easily used in an industrial surrounding. In general, the pipe is so slender that a conventional finishing tool is hardly inserted into the pipe deeply, being impossible to finish. Therefore, a new technology has been considered to finish inside of a slender ceramic pipe by a simple technique. In this experimental, Magnetic Abrasive Machining is applied for the inner surface of silicon nitride fine ceramic pipe using ferromagnetic particles mixed with chromium-oxide powder. It is shown the initial roughness of 2.6㎛ Ry(0.42㎛ Ra) in the inside surface can be precisely finished to the roughness of 0.1㎛ Ry(0.01㎛ Ra). This paper discusses the outline of the processing by the application of magnetic abrasive machining and a few finishing characteristics.

특발성비후성두개경막염: 증례 보고

박원규,변우목,김동석,Park, Won-Gyu,Byeon, U-Mok,Kim, Dong-Seok 대한영상의학회 2003 대한영상의학회지 Vol.49 No.4

특발성비후성두개경막염은 다른 영역의 질환을 배제함으로써 얻을 수 있는 매우 드문 질환이다. 53세 남자가 1개월간의 지속적인 두통과 우안 시력 감소를 주소로 내원하였다. 우측 해 변동 내의 종괴 및 양측 전두엽 부문의 비후된 경막 모두 MR 관상면 T1 강조영상에서 뇌회색질과 동등한 신호강도, T2 강조영상에서 저신호강도를 보였으며, 조영증강후 T1 강조영상에서 양측 선두엽 부분의 경막은 미만성으로 두껍고 비교적 강한 조영증강을 보였으나 해면동내 종괴는 조영증강되지 않았다. 저자들은 수술로 확진된 특발성비후성두개경막염 1예를 경험하였기에 그 방사선학적인 소견을 보고하고자 한다. Idiopathic hypertrohpic cranial pachymeningitis is rare, and is essentially a diagnosis of exclusion. A 53-year-old man presented with headache and visual loss in the right eye, first experienced a month earlier. MR images depicted a mass in the right cavernous sinus. At T1-wighted imaging, both the mass and the thickened dura mater present in both fromted lobes were isointense, while at while T2-weighted imaging, the signal intensity of both the mass and the dura mater was low. After the injection of contrast medium, pachymeningeal enhancement was obserbed. We report the radiologic findings in a case of idiopathic hypertrophic cranial pachymeningitis, confirmed surgically and pathologically.

수술 후 재발한 후복막에서 발생한 염증성 근섬유모세포종: 증례 보고

박원규,장재천,Park, Won-Gyu,Jang, Jae-Cheon 대한영상의학회 2003 대한영상의학회지 Vol.48 No.6

염증성 근섬유모세포종은 근섬유세포를 포함한 다양한 염증세포와 혈관 섬유성 조직으로 구성된 비종양성 양성 병변이며 때로 악성 종양과 유사한 소견과 경과를 보인다.폐,간,안와,피부,장간막,그리고 상악동 등에 보고된 바 있으나 후복막에 생긴 경우는 국내에서는 보고된 바 없다. 저자들은 우측 복부에서 촉지된 종괴를 주소로 내원한 45세 남자환자에서 수술 후 후복막에서 발생한 염증성 근섬유모세포종으로 확진되었고, 이후 절제 변연부에서 재발한 1예를 보고한다. Inflammatory myofibroblastic tumor is a rare benign condition of unknown etiology, and may simulate malignancy. Histologically, it is composed of myofibroblasts, plasma cells and histiocytes, and is found in the lung, liver, orbit, skin, mesentery, retroperitoneum and maxillary sinus. We report a case of postoperative recurrent inflammatory myofibroblastic tumor of the retroperitoneum, occurring in a 45-year old man who complained of a palpable abdominal mass.

간동맥화학색전술 후 생긴 간내 담즙종: 영상소견, 임상경과 및 치료에 관한 분석

박원규,장재천,조재호,Park, Won-Gyu,Jang, Jae-Cheon,Jo, Jae-Ho 대한영상의학회 2003 대한영상의학회지 Vol.48 No.4

목적: 간세포암 환자에서 동맥화학색전술후 발생한 담즙종의 영상소견을 평가하고, 임상경과 및 치료에 대해서 알아보고자 하였다. 대상과 방법: 간세포암 환자에서 동맥화학색전술후 담즙종이 생긴 11예를 대상으로 역동적 CT 및 혈관조영 소견을 후향적으로 분석하였다. 간동맥과 간문맥의 혈류 변화, 담도확대 유무, 혈청 총빌리루빈치 등에 대해 알아보았다. 추적 검사에서 담즙종의 크기 변화를 관찰하고, 추가적인 치료 여부와 임상 경과에 대해서 알아보았다. 결과: 추적 혈관조영 사진상 간동맥 폐쇄가 11예 모두에서 보였고 우간동맥폐쇄가 8예, 분절간동맥폐쇄가 3예였다. 간문맥 혈류감소를 보인 경우가 7예, 간문맥혈전이 1예였다. CT에서 간내담도확대는 전 예에서 발견되었으며 담즙종 발견된 전후로 총빌리루빈치는 큰 변화가 없었다. 추적 검사에서 담즙종의 크기 증가가 있었던 경우는 5예였으며 이 중 4예에서는 감염이 동반되어 있었고 전 예에서 경피적 배액술을 시행하였다. 6예에서는 무변화 혹은 크기의 감소를 보였으며 추적 CT에서 간의 동측엽 혹은 동측분절의 위축이 동반되어 있었다. 결론: 간동맥화학색전술 후 담즙종이 생겼을 때 전 예에서 혈관조영 사진상 간동맥 폐쇄 소견이 있었다. 추적검사상 담즙종의 크기가 증가하거나 감염의 징후가 있는 경우에는 적극적인 치료가 필요할 것으로 생각된다. Purpose: We evaluated the imaging findings, clinical course and treatment of biloma after transcatheter arterial chemoemolization (TACE) of hepatocelluar carcinoma (HCC). Materials and Methods: After TACE of HCC in 11 patients with intrahepatic biloma, the findings of dynamic CT and angiography were retrospectively analysed. Hemodynamic change occurring in the hepatic artery and portal vein, the presence of intrahepatic bile duct dilatation, and serum bilirubin levels were analyzed. Changes in the size of the biloma at follow-up study, the extent of additional management, and the overall clinical course were also analyzaed. Results: Hepatic artery obliteration was observed in all cases; this involved the right hepatic artery in eight, and the segmental artery in three. There was decreased portal venous flow in seven cases and portal thrombosis in one. The intrahepatic duct was dilated in all cases but significantly elevated serum bilirubin levels were not noted. Follow-up study showed that in five cases the size of the biloma had increased; in four of these there was infection, and drainage was performed. In the remaining six cases the size of the biloma did not change, even where a segment or lobe had atrophied. Conclusion: Angiography showed that after TACE hepatic arterial obliteration occurred in all patients with intrahepatic biloma after TACE. During infection or where a biloma has increased in size, intervention is required.

창경궁 통명전 목부재의 연륜연대 측정 -방에서 마루로 변형된 시기규명을 중심으로-

박원규,손병화,한상효,Park, Won-Kyu,Son, Byung-Wha,Han, Sang-Hyo 한국건축역사학회 2003 건축역사연구 Vol.12 No.3

Tree-ring chronologies can be used to date historical buildings by matching them with the chronologies of living trees or previously dated samples. Tree-ring dating gives a calendar year to each tree ring and produces the felling dates of logs or woods which had been used for buildings. In Korea, several chronologies of Japanese red pine(Pinus densiflora Sieb. et Zucc., 'sonamu' in Korean), a major species for the wooden building materials, have been developed and used for dating historical buildings. In this study, Tongmyungjeon Hall of Changkyung Palace in Seoul was dated by tree rings. The present Tongmyungjeon Hall was known to be reconstructed in A.D. 1834 after burned-out in A.D. 1790. We sampled total of 122 wood samples which were replaced during the repair process in 2002-2003. Felling dates of the samples were determined by the dendrochronological crossdating method. Crossdating method employs graphic comparison of the master patterns (ring-width chronologies of known dates) with those of the sample chronologies of unknown dates. Tree-ring dates confirmed that the reconstruction of 1834 utilized second-handed timbers as well as fresh-cut ones. The felling dates of wooden floor frames were mostly A.D. 1913, indicating the 'Ondol' floors were changed to the wooden floors around 1914 when the Japanese rulers brutally destroyed the royal Korean Palaces and transformed palace buildings to their offices or exhibition halls after occupying Korea in 1910. This study proved that tree-ring dating was a useful and accurate method to identify the critical dates for the history of Korean traditional buildings.