에폭시 수지를 혼합한 아스팔트 방식재의 특성

홍석표,최상구,강석근,이화우 全北大學校 1995 論文集 Vol.39 No.-

Epoxy resins were mixed with asphalt solution in the range of 0 - 60phr for the total components. The blending properties, curing properties, and surface properties for mixtures were investigated experimentally. Compatability of epoxy resins with asphalt were relatively good over mixture temperature 50℃. Interpenetrated polymer networks(IPNs) were partially formed between epoxy resins and asphalt. Increase of hardness was depended on the crosslinking density of epoxy resins and oxidation of asphalt. Defects of coated surface including crater, pinhole, and crack could be improved by adding epoxy resins 20 phr.

쓰레기종량제 실시전후의 생활폐기물 소각장 배출 유해가스 농도

홍성철,장봉기,이종영,구영수 순천향대학교 기초과학연구소 1998 순천향자연과학연구 논문집 Vol.4 No.1

This study was conducted to compare the concentration of sulfur oxides and nitrogen oxides emitted from the household incineration facility in Taegu city before and after the adoption of garbage packing system. Their concentrations were measured by an automatic analyzing equipment(MCS 100) at Sung-Suh household waste incineration facility in Taegu city using the non-dispersion infrared absorption analysis method from January 1 to June 30, 1994 before the adoption of the garbage packing system, and from January 1 to June 30, 1995 after the adoption of the system. The means of daily maximal concentration and daily average concentration of the emitted sulfur oxides were 40.9±23.00ppm and 21.4±6.18ppm in 1994, and 75.7±59.43ppm and 22.0±8.95ppm in 1995, respectively. In 1994, the concentration showed a gradual reduction from January until June, but there was a marked variation in 1995. By the day of the week, both 1994 and 1995 showed the lowest figures on Sundays. In the multi-variable analysis of variance to nitrogen oxides, there was not a noticeable statistical figure by the year and by a day of the week, but there did exist a noteworthy difference among the monthly emission concentrations (p<0.05). The means of daily maximal concentration and daily average concentration of the emitted nitrogen oxides were 175.6±23.82ppm and 122.3±26.92ppm in 1994, and 143.7±16.57ppm and 100.2±25.85ppm in 1995, respectively. By month, the means of its daily average concentration was lowest in June, 1994 at 89.4±26.29ppm and 72.7±31.36ppm in April, 1995. By the day of week, there was not much variation, it was lowest on Saturdays at 116.6±24.74ppm in 1994 and on Wednesdays at 93.4±25.79ppm in 1995. In the result of the multi-variable analysis of variance, it was significant that there was a difference in the nitrogen oxides emission concentration between the by-the-year figure of p<0.05 and by-the-mouth figure of p<0.05. This result suggests that the adoption of garbage packing system may affect the emission concentration of emitted nitrogen oxides from household waste incineration facility.

자외선 경화형 불포화 폴리에스테르 수지의 합성과정이 저장안정성에 미치는 영향

洪錫杓,崔相久 全北大學校 1992 論文集 Vol.34 No.-

Storage stability of UV curable unsaturated polyester was studied in accordance with synthesis process and inhilitor charging. When resin was synthesized at 160∼170℃, storage stability was mainly influencd by reaction time. THQ showed best storage stability among inhibitors. Appropriate charge of THQ was 150ppm in initial of first reaction, 350ppm in initial of second reaction and 350ppm in SM thinning.

벽시계틀 소재로 사용되는 목재와 플라스틱의 접착력 향상에 관한 연구

洪錫杓,崔相久,金鍾石 全北大學校 1991 論文集 Vol.33 No.-

Wood and plastic were used as elemental materials of the frame of clock. In this research, it was studied to improve adhesive strength between this materials by new adhesion process. Vinyl or acryl emulsion(H-403, H-422, Y-840, Y-850) was used as the adhesive. The adhesive properties was tested experimantally on various partial process including sanding, cleaning of sanded surface and pressing of bonded areas. The results obtained in this experiments were follows : 1) Y-850 represented most excellent adhesive properties. 2) The maximum of adhesive strength could be obtained by sanding with sand paper #600, pressing of 0.3∼0.5kg/㎠, and cleaning with acetone. In that case, increase of 20% in adhesive strength was showed than obtained by traditional process.

카본블랙의 종류 및 배합제의 혼합방법에 따른 NR/HNBR 블렌드의 특성

洪錫勻,庾吉祥,金鍾石,崔相久 全北大學校 1992 論文集 Vol.34 No.-

It was studied how physical properties, heat resistance, oil resistance, ozone resistance of NR(natural rubber)/HNBR(hydrogenated acrylonitrile butadiene rubber) blends influenced by different mixing methods and various carbon black types. Of the various mixing methods, masterbatch mixing method was better than others in considering the overall stabilities of the compounds. The most important parameter which influenced on heat, oil and ozone resistance was rubber material than sorts of carbon black. The resistance for heat, oil and ozone of NR compounds were improved by blending HNBR and these effects were revealed clearly at elevated temperatures.

太谿穴의 臨床 活用에 대한 文獻考察

구성태,송문영,강정묵,김용명,박보라,이은석,홍정아,김경식,손인철 한국전통의학연구소 2003 한국전통의학지 Vol.13 No.1

Literally, the mean of Tae-gye is highest brook. And on the basis of the acupuncture theory, Tae-gye point is the Soo earth point and source point of the Kidney Channel as well. In addition, Tae-gye point is one of the Yang-Returning Nine points. We were trying to study bibliographically on the Tae-gye point because Tae-gye point can be used very broadly across the symptoms in the theoretical aspect described above. As a results, we found out that according to the classical books of acupuncture, Tae-gye point is entering point of the Meridian Water as a source point and can be used at both Kidney-Sufficient Syndrom and Kidney-Deficient Syndrom. And Tae-gye can be applied to the disease of kidney or bladder that is urogenital symtoms, Also, Tae-gye is an useful option of tooth-ache, asthma, indigestion, constipation, edema etc whose cause is related with decrease of Kidney ki.

CTBN고무 분산 에폭시 복합재의 기계적물성 및 파단면에 관한 연구

洪錫杓,崔相久 全北大學校 1989 論文集 Vol.31 No.-

We examined the mechanical properties (flexural and impact) and fracture surface of CTBN(carboxyl terminated butadiene acrylonitrile) rubber dispersed epoxy composites which are cured with MTHPA(methyl tetrahydro phthalic anhydride) or DICY(dicyandiamide). Rubber dispersed epoxy composites are prepared to blend epoxy mixture with CTBN rubber or CTBN rubber modified epoxy. It contains 0-25% CTBN rubber of liquid compoment. The results obtained in this experiment are as follows ; 1. The flexural stength is better in using the CTBN rubber than CTBN rubber modified epoxy. 2. In excess of 25% CTBN rubber, the cured epoxy composites are closed to rubber rather than epoxy in properties. It is very flexible. 3. In respect of the flexural stength and flexural modulus, CTBN x13 rubber is superior to CTBN x8 rubber. In excess of 5% CTBN rubber, The mechanical properties of both decrease sharply. 4. In respect of the impact stength, flexural stength and rubber dispersion, MTHPA is superior to DICY.

유전자 알고리즘에 의한 모발로봇의 자세/위치 제어

한성현,이우송,김윤구,김홍래,조창제 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

This paper proposed trajectory tracking control of Mobile Robot. Trajectory tracking control scheme are Real coding Genetic-Algorithm and Back-propergation Algorithm. Control scheme ability experience is proposed by simulation.

일부 부인과 양성 질환자의 지방조직 및 혈청의 PCBs와 DDE 농도

박성균,이강숙,노영만,구정완,민선영,한진구,고원경,김미란,정재근,이종승,김진홍 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.1

목적 : 본 연구는 지방조직과 혈청의 PCBs와 DDE 농도를 측정하고, 이에 영향을 미치는 것으로 알려진 요인들과의 관련성을 평가하고자 하였다. 방법 : 유방암, 자궁내막증 등 유기염소계 화합물의 영향이 있는 것으로 알려진 호르몬 관련 질병을 제외한 부인과 환자 52명을 대상으로 지방조직과 혈청을 분석하였으며, 설문조사를 통하여 연령, 교육수준, 직업, 비만도, 흡연과 음주, 출산력, 수유력등을 조사하였다. 지방조직과 혈청의 PCBs와 DDE 농도는 가스크로마토그래피를 사용하여 측정하였다. 결과 : 지방조직의 경우, 13개 PCBs congeners 농도의 합은 중앙값이 48.29 ng/g, 기하평균값이 56.78 ng/g이었고, DDE 농도는 중앙값이 142.89ng/g, 기하평균값이 117.06 ng/g이었으며, 혈청의 경우는 PCBs congeners 농도의 합은 중앙값이 4.67 ㎍/L, 기하평균값이 4.85 ㎍/L이었고, DDE 농도는 중앙값이 1.75 ㎍/L, 기하평균값이 2.09 ㎍/L로 나타났다. 지방조직과 혈청의 DDE 농도 사이는 높은 상관성을 보였으나(r²=0.310, p=0,0002), PCBs는 상관성이 약한 것으로 나타났다(r²=0.029, p=0.2582). 영향요인을 범주화한 후 로그변환 시킨 지방조직과 혈청의 PCBs, DDE 평균의 차이를 분석한 결과, 지방조직의 DDE만이 출산자녀수(p=0.015), 초산연령 (p=0.014), 비만지수(p=0.035)와 연관성이 발견되었다 다중회귀분석의 결과 지방조직의 DDE는 출산자녀수가 적을수록, 초산연령이 늦을수록 증가하는 경향을 보였다. 결론 : 출산자녀수와 초산연령, 비만도가 지방조직의 DDE와 관련성을 보였으며, 또한 유기염소계 화합물의 장기간의 노출에 의한 영향을 평가하는데 있어서 혈청보다 지방조직이 더 유용한 생물지표임을 알 수 있었다. Objectives : This study was purposed to determine the levels of PCBs and DDE in adipose tissue and serum and to evaluate the relations with factors affecting these levels. Methods : We analyzed adipose tissues and sera from 52 gynecologic benign disease patients aged 27-78 years, except hormonal diseases such as breast cancer and endometriosis. We also surveyed age, education, occupation, body mass index (BMI), smoking, drinking, number of children, and duration of breastfeeding by questionnaires. Tissue and serum levels of PCBs and DDE were measured using gas chromatography. Results : The median and geometric mean levels of PCBs were 48.29 ng/g, 56.78 ng/g for adipose tissue and 4.67 ㎍/L, 4.85 ㎍/L for serum, and those of DDE were 142.89 ng/g, 117.06 ng/g for adipose tissue and 1.75 ㎍/L, 2.09 ㎍/L for serum, respectively. Adipose tissue and serum levels for DDE showed high correlation (r²=0.310, p=0.0002), but those of PCBs didn't (r²=0.029, p=0.2582). In analyses of the differences of the means of log transformed adipose tissue and serum PCBs and DDE levels for groups of potential covariates, only adipose tissue DDE levels were significantly associated with number of children (p=0.015), age at first birth (p=0.074) and BMI (p=0.035). In multiple regression analysis, adipose tissue DDE levels were significantly increased with decreasing number of children and increasing age at first birth. Conclusions : This study suggested that parity and adiposity were associated with levels of DDE in adipose tissue, and adipose tissue is a better biomarker than serum for evaluating the long-term exposure of organochlorines.

보강섬유의 배향이 고분자 복합재료의 물성에 미치는 효과

崔相久,李和雨,洪錫杓 全北大學校 1993 論文集 Vol.35 No.-

The tensile and flexural strength of unsaturated polyester laminated with 20% glass-fiber(volume %) were tested. Those were compared with its abtained from Holister's equation. The strengths of laminated polyester were mainly depended on the properties of interface between fiber and resin than the strengths of material itself. For crossplied laminates, correct strength coincided with Holister's were not abtained, but could be explained by Holister's theory. The fractural strength of orientation angle 0∼5˚ was influenced by shear resistance besides the strength of glass fiber.