단파장 자외선(254nm)에 노출된 고밀도 폴리에틸렌 수지의 카르보닐 지수(CI)와 기계적 물성 변화의 관계에 관한 연구

김창환 ( Chang Hwan Kim ),신진용 ( Jin Yong Shin ) 한국공업화학회 2013 공업화학 Vol.24 No.2

This paper studied the possibility to predict a mechanical property variation from changes in created carbonyl bands by irradiating the surface of high-density polyethylene with short-wavelength ultraviolet radiation of 254nm to induce a fast chemical degradation. The meaning of this study lies in checking whether a mechanical property change with the same chemical property as the induced optical deterioration is caused by using a UVC lamp with high photon energy instead of optical deterioration via xenon arc light source and outdoor exposure test via natural sunlight requiring a long time. The mechanical strength of high-density polyethylene checked by a tensile test and a creep destruction test showed a similar tendency with CI changes. In particular, the yield strength and elongation had a close relationship with the exposure time to ultraviolet radiation. Accordingly, this paper presented a method to grasp the mechanical property change outdoors requiring a long time more fast through the relationship between the mechanical property change and the carbonyl index using a UVC lamp causing the fast surface degradation.

後鼻漏를 主訴로 한 慢性 副鼻洞炎 患者의 治驗 1例

김창환,선영재,임웅경,김현기,Kim, Chang-hwan,Sun, Young-jae,Lim, Woong-kyoung,Kim, Hyun-gi 대한한방안이비인후피부과학회 2003 한방안이비인후피부과학회지 Vol.16 No.2

Paranasal sinusitis is a common disease in the otorhinolaryngology area. It is the change of inflammation at the mucous membrane which surrounds paranasal sinus. Chronic paranasal sinusitis is a chronic inflammation disease with purulent, mucous rhinorrhea, postnasal drip and cough. The attacked period continues above three months and it repeats exacerbation and remission. We diagnosed and treated an outpatient who complains postnasal drip of chronic paranasal drip of chronic paranasal sinusitis based on the Oriental medical theories and had good result.

안면신경마비에 대한 안륜근 미소안면침 증례보고

조아름,김지현,주경옥,원재선,김창환,Cho, Ah-Reum,Kim, Ji-Hyun,Chou, Ching-Yu,Won, Jae-Sun,Kim, Chang-Hwan 대한한방안이비인후피부과학회 2010 한방안이비인후피부과학회지 Vol.23 No.2

Objective : This study was designed to evaluate the effect of Miso Facial Acupuncture on Orbicularis Oculi muscle. Methods : Two men and four women with Facial nerve palsy were recruited. Miso Facial Acupuncture on Orbicularis Oculi muscle was performed two times a week for three weeks. The effects of the treatment were evaluated by H-B scale, Y-system and clinical symptom. Results : Before treatment with Miso Facial Acupuncture, three patients showed H-B scale improvement and the other three patients had no change. and four patients showed Y-system improvement and the other two patients had no change. In six cases, the patients had improvement in clinical symptom related with Orbicularis Oculi muscle function. Conclusion : Miso Facial Acupuncture on Orbicularis Oculi muscle showed significant improvement in facial nerve palsy.

디지털 치의학의 과거와 현재 그리고 미래

김창환,Kim, Chang Hwan 대한심미치과학회 2015 Journal of the Korean Academy of Esthetic Dentistr Vol.24 No.1

치과계에서 캐드캠이 보급되면서 본격적으로 사용한 지 15년이 넘었다. 코핑 정도의 역할에서 구치부 전부관으로 확대되었고, 최근에는 전치부에서도 많이 사용하는 추세이다. 장비의 발전도 비약적이었지만 지르코니아 블록의 발전이 가장 많이 이루어졌다. 개개인의 능력이나 경험 차에 의해 차이는 있을 수 있겠지만, 도재를 올리지 않고 지르코니아에 컬러링만으로도 얼마든지 색을 표현 할 수 있다. 또한 캐드 디자인 만으로도 표면의 질감을 표현하는 것에 우리가 알고 있는 만큼 가능하다. 본 논문에서는 이러한 디지털 치과학의 변천과정을 정리해 보고자 한다. Since its introduction to the dentistry, the CAD/CAM technology has been used over fifteen years. The application of CAD/CAM started from coping fabrication, expanded to the posterior full crown, and anterior restoration manufacture has also become widespread recently. While the development of machine was rapid, the advance of zirconia block was the fastest. Although some differences exist among individuals, the various natural tooth color can be expressed through the zirconia coloring itself without porcelain build up. And the texture characteristics can be reproduced just by CAD design. In this article, the development history of digital dentistry was summarized.

하지길이균차에 대환 임상평가와 치료

김창환,김종덕,Kim, Chang-Hwan,Kim, Jong-Deog 척추신경추나의학회 2004 대한추나의학회지 Vol.5 No.1

Objectives : Visual check and X-ray are commonly used by chiropractors to estimate ieg length inequality, This study have three categories: diagnosis for anatomic leg length inequality; difference between anatomic and functional leg length inequality; theraphies for anatomic or functional leg length inequality. Methods : We referred to a PubMed site by using word of 'leg length [JU] J Manipulative Physiol Ther', only items with abstracts. Results : We searched 26 articles in J Manipulative Physiol Ther with the key word-Ieg length. Conclusion : 1. Radiographs were most accurate and commonly used by chiropractors to measure anatomic leg length inequality, clinically wood block, tape measure, visual check are acceptable. 2. There was no article about difference between anatomic and functional leg length inequality. 3. Heel lift was commonly used with conservative theraphy for anatomic leg length Inequality. 4. Chiropractors have not yet proved that the supposed positive effects are a result of a reduction of subluxation, The detection of the manipulative lesion in the sacroiliac joint depends on valid and reliable tests, Because such tests have not been established, the presence of the manipulative lesion remains hypothetical. Great effort is needed to develop, establish and enforce valid and reliable test procedures.

한강수계 하수관거정비 시범사업

김창환,Kim, Chang-Hwan 한국상하수도협회 2003 한국상하수도협회지 Vol.4 No.-

Glycyrrhizin의 Hypocholesteroleinic Action에 관(關)한 연구(硏究)

김창환,Kim, Chang-Hwan 대한약리학회 1965 대한약리학잡지 Vol.1 No.1

Glycyrrhizin, an active constituent of Glycyrrhiza, was chemically extracted and its hypocholesterolemic activities were studied in rats. Following were the results: 1. The Sprague Dowley rats fed with the standard diet were divided into 4 groups, $50{\sim}60$ in each, and glycyrrhizin was given in doses of 0 (control), 0.5, 1.0 and 2.0mg per 100gm body weight daily for 10, 20, 30, and 60 days. Glycyrrhizin showed more or less the hypocholesterolemic activities in all animals. All of the animal groups to which 1. 0mg and 2.0mg of glycyrrhizin were given died before 60 days, while no mortality cases was noted in the group to which 0.5mg of glycyrrhizin was given. 2. Cholesterol administration induced hypercholesterolemia in all experimental animals, however, simultaneous administration of cholesterol with 0.5mg of glycyrrhizin suppressed the rise of the total serum cholesterol levels. The former group did not survive until 56 days, while the latter did. 3. Glycyrrhizin also Suppressed the cholesterol biosynthesis and incorporation of cholesterol in the liver tissues. 4. Glycyrrhizin induced the increase of the fecal excretion of the sterol compounds.

시론-2000년대를 내다 보면서

김창환,Kim, Chang-Hwan 한국과학기술단체총연합회 1986 과학과 기술 Vol.19 No.7

미사일 Fin 액츄에이터용 서보모터의 외란 토크 억제 제어

김창환,Kim, Chang-Hwan 대전대학교 군사연구원 2003 군사학연구 Vol.1 No.-

In this paper, we propose a generalized disturbance torque suppression control scheme of servo motors for missile fin actuators. Our controller consists of both a model based feed-forward controller and a stabilizing feedback controller. The feed-forward controller is designed such that the output of nominal plant tracks perfectly the reference position command with a desired dynamic characteristics. The feedback controller stabilizes the overall closed loop system. Furthermore, the feedback controller contains a free function that can be chosen arbitrary. The free function can be designed so as to achieve both the suppression of disturbances and the robustness to model uncertainties. In order to illuminate the superior performance of our control scheme to the conventional ones, we present some simulation results.

도시근린공원 식생의 생태학적 진단 -전주화산공원을 중심으로-

김창환,명현,Kim, Chang-Hwan,Myung, Hyun 한국조경학회 2001 韓國造景學會誌 Vol.28 No.6

This study is to offer the basic information and materials for the restoration of the urban forest and the ecologically healthy and continuous green belt through the investigation and the analysis on the vegetation in Hwasan Park, Chonju-City. The flora of Hwasan Neighborhood park was composed of 86 families 230 genera, 261 species, 35 varieties, 1 formae or 298 Taxa. Among them, calculation of Pte-Q Index represented 0.60, Fisher's Index. Some characteristics of the plants in this area have represented such as Th-D1-R5 type in biological type, erect form(64.6%) in growth type, 30 taxa in naturalized plants. The life form spectra investigated from Hwasan neighborhood park was recognized as the following M"17.4%, N:11.4%, E:0.3%, Ch:0%, H:29.8%, G:6.7%, HH:0%, Th:34.2%. By the Z-M method 5 plant communities and 3 afforestation were recognized; Quercus variabilis community, Q.acutissima community, Q.serrata community, Sorbus alnifolia community, Pinus densiflora community, P.rigida afforestation, Robinia pseudo-acacia afforestation and Larix leptolepis afforestation. The actual vegetation map constructed on the grounds of the communities classified and other data. The pattern of successional trend of tree species might be suggested: L. leptoleipis, P. rigida and P. densifloralongrightarrowQ.variabilis and Q.acutissimalongrightarrowS.alnifolia and Q.serratalongrightarrowCarpinus tschonoskii community. Three measurements of species diversity (richness index(SR), Shannon-Wiener index(H'), evenness index(J')) and their relationship with community type were studied in the surveyed plant communities. Q.serrata community was higher in SR, H', J' than the other communities, whereas R.pseduo-acacia afforestation was low. Finally, The vegetation of the Hwasan neighborhood park must not allowed any more. Nothing ca be better than native states in preserving the ecosystems.tems.