NR과 SBR 가황물의 경도와 강성도에 대한 온도의 영향

진현호 ( Hyun Ho Jin ),홍창국 ( Chang Kook Hong ),조동련 ( Dong Lyun Cho ),강신영 ( Shin Young Kaang ) 한국고무학회 2007 엘라스토머 및 콤포지트 Vol.42 No.3

본 연구에서는 고무제품의 수치 안정성과 성능유지에 직접적으로 영향을 미치는 중요한 특성 중 하나인 온도변화에 따른 고무재료의 경도변화를 고찰하였다. 새롭게 제작된 International Rubber Hardness Degree(IRHD, Normal type) 경도측정 시험기를 사용하여 미충전된 NR과 SBR시편의 여러 온도에서 경도변화를 측정하였으며 Young`s modulus 값과 비교하였다. NR과 SBR 모두 유리전이온도 근처에서 경도와 Young`s modulus의 급격한 변화를 보였다. 온도가 증가함에 따라 경도와 Young`s modulus 값이 증가하는 경향을 보였으며 이는 분자의 운동성과 엔트로피 영향으로 해석할 수 있다. 카본블랙과 실리카가 충전된 NR과 SBR의 경우 충전제의 함량이 증가함에 따라 경도에 미치는 온도의 영향이 감소함을 관찰하였다. Hardness of rubbery materials, which is important for dimensional stability and product performance, was investigated upon temperature change in this study. A newly developed IRHD (International Rubber Hardness Degree) tester was used to measure the hardness changes of NR and SBR specimens at various temperatures and the hardness values were compared with the Young`s modulus. The hardness and Young`s modulus of NR and SBR showed an abrupt change near the glass transition temperatures. The hardness and Young`s modulus were increased by increasing temperature due to the increased random chain conformation of molecules. The effect of temperature on hardness and Young`s modulus of NR and SBR specimens filled with carbon black and silica was decreased by increasing filler content.

고분자형 자외선 안정제를 함유한 SBR과 NR의 UV 노화 거동에 관한 연구

남경태 ( Kyoung Tae Nam ),홍창국 ( Chang Kook Hong ),채규호 ( Kyu Ho Chae ),강신영 ( Shin Young Kaang ) 한국고무학회 2006 엘라스토머 및 콤포지트 Vol.41 No.3

본 연구에서는 고분자형 자외선 안정제 DGEBA-HALS의 광분해 억제 효과를 평가하기 위해 SBR과 NR 고무를 사용하여 광안정제 첨가에 따른 UV 조사 영향을 고찰하였다. 이를 위해 광안정제를 첨가하지 않은 배합고무, 사용화된 광안정제인 Cyabsorb UV-3529를 첨가한 배합고무, 그리고 고분자형 DGEBA-HALS를 첨가한 배합고무의 영율, 인장장고, blow-off 변형, 가교밀도 측정을 통한 시편의 물리적 특성변화 등을 관찰하였다. UV 조사 후 모든 시편에서 영율이 증가하였으며 인장강도는 광안정제를 첨가한 시편이 첨가하지 않은 시편보다 우수했다. 특히 NR의 경우 DGEBA-HALS 첨가 시 인장강도가 향상되었다. Blow-off 변형 실험결과도 영율 실험 결과와 비슷하였다. UV-vis transmissinon spectra를 통한 SBR 배합고무의 투과도를 조사한 결과 광안정제를 첨가함으로써 약 4%의 향상된 투과도를 보였다. Cyabsorb UV-3529와 DGEBA-HALS의 첨가는 비슷한 경향의 투과도를 나타내었다. SEM을 통해 시편의 표면을 관찰한 결과 광안정제를 첨가함으로써 UV 조사에 의한 균열의 크기가 작아짐을 알 수 있었고, 특히 DGEBA-HALS는 상용화된 Cyabsorb UV-3529 보다 더 좋은 광분해 안정효과를 갖는 것을 확인할 수 있었다. The retardation effects of a new polymeric UV stabilizer, DGEBA-HALS, on the UV degradation of SBR and NR were investigated in this study. The UV degradation behaviors of three different rubber compounds, without any photostabilizer and with commercial Cyabsorb UV-3529 and DGEBA-HALS, were compared. Also, the physical characteristics such as Young`s modulus, tensile strength, blow-off deformation and crosslink density were examined. The Young`s modulus was increased by UV irradiation for all samples, and the tensile strength, after UV irradiation, of the compound with UV stabilizer was better than that of the compound without stabilizer. Especially, the tensile strength of UV irradiated NR was improved by adding DGEBA-HALS. The results of blow-off deformation were in accord with those of Young`s modulus. The degree of transmission of SBR compounds obtained from UV-vis transmission spectra was improved about 4% by adding the UV stabilizer. Commercial Cyabsorb UV-3529 and DGEBA-HALS showed similar trends of transmission. The SEM photographs of SBR surface showed that the size of cracks created by UV irradiation became smaller by adding UV stabilizer. In particular, it is observed that the stabilization effect of DGEBA-HALS was better than that of commercial Cyabsorb UV-3529.

삼작용성 단량체인 TTE-3MA 또는 TTE-3MPA를 포함한 공중합체의 중합수축율과 중합전환율

신영국 충북대학교 과학교육연구소 2003 과학교육연구논총 Vol.19 No.1

삼작용성 단량체로 알려진 TTE-3MA(tris[4-(2'-hydroxy-3'-methacryloloxypropoxy)phenyl]methane) 또는 새롭게 합성한 TTE 3MA의 유도체인 TTE-3MPA (tris[4-(2'-hydroxy-3'- (2″-methyl-2″-pentenoloxy)propoxy)phenyl]methane)을 포함한 공중합체의 중합수축율과 중합전환율을 부피측정법과 적외선 분광광도법을 이용한 봉우리 높이 측정법에 의하여 각각 조사하였다. 기존에 사용하고 있는 이작용성 단량체인 2.2-bis[4-(2'-hydroxy-3'-methacryloyloxypropoxy)-phenyl]propane(bis-GMA)와 Tri(ethylene glycol) dimethacrylate (TEGDMA) 만을 포함한 치과충전재용 공중합체에 비하여, 중합수축율은 10% 이상 향상되었으며, 중합전환율도 적당하였다. 따라서 새롭게 개발한 삼작용성 단량체를 포함한 공중합체들을 치과용 레진시멘트 주성분으로 사용할 수 있을 것이다. The polymerization shrinkage ratios(%) and polymerization conversion ratios(%) of the copolymers including tri-functional monomer, tris[4-(2'-hydroxy-3'-methacryloyloxy-propoxy)phenyl]methane (TTE-3MA), or newly synthesized tri-functional monomer, tris[4-{2'-hydroxy-3'-(2"-methyl-2"-pentenoyloxy)propoxy)phenyl]methane (TTE-3MPA) were investigated by volumetric method and peak height method using IR spectrophotometry, respectively. The shrinkage ratios were improved by more than 10% and the conversion ratios were optimal in comparison with the usually used copolymer for dental filler including only bi-functional monomer 2,2-bis[4-(2'-hydroxy-3'-methacryloyl-oxyproposy)phenyl]propane (bis-GMA), and tri(ethylene glycol) dimethacrylate (TEGDMA). Therefore, the newly developed copolymers with the tri-functional monomers are expected to be applied to the dental composite resin cements for fillers.

不當廣告規制手段으로서의 訂正廣告命令에 관한 硏究

신승국,김영조 龍仁大學校 1998 용인대학교 논문집 Vol.16 No.-

At present, the corrective advertising orders is not applied to regulation of unfair or deceptive advertising. It is necessary to make use of corrective advertising orders positively for the sake of eliminating deceptive residual effects in consumers minds. In the light of corrective advertising cases in the United States, the following conclusions are derived as follows : First, in the type of corrective advertising orders, the type of inserting corrective message in the future advertising is more effective than it of public notice., Second, in principle, corrective advertising should be campaigned in all adversing media that deceptive advertising was committed. Third, it is desirable that corrective advertising should be required in within the limits of one gear and 25% of advertising costs.

女性 同性愛 1例 : 精神力動的 考察을 中心으로

申榮宇,梁昌國,廉泰鎬,張煥一 서울대학교 의과대학 정신과학교실 1983 精神醫學報 Vol.7 No.12

3차원 곡면의 비접촉 측정법에 관한 연구 : 광촉침법에 의하여 by the Optical Probe Method

申聖國,姜永準 全北大學校 1993 論文集 Vol.35 No.-

This paper proposes a non-contact measuring system using one point measuring method to measure surface profiles of dies and clay models for practical use in the field of production engineering. The system has laser beam as a measuring probe in a contact measuring system. The CCD linear image sensor is used to detect 300㎜ measurement range and displacement of measured surfaces from an origin. There is no mechanical interference between the measuring system and a measured surface in this system. Therefore, high speed measurement is to be possible. In this measuring system, short time of 500-600㎳ including data processing time was needed to measure one point. As experimental results, the standard deviation was estimated to be 800㎛.

보안정책 정보모델링과 보안정책 관리구조

서명국,송현교,신영석 호남대학교 대학원 2004 호남대학교 대학원 논문집 Vol.4 No.-

The purpose of network administration is to give clients the high quality services of well-managed stability and efficiency. Contemporary network administration has been managed by the way of controlling network elements through network status monitoring. The larger in scale and the more complex the network is, the more complicated and difficult network administration has become because of the obstacles which are simultaneously occurred. Therefore, the PBNM(Policy-Based Network Management is proposed to ensure the simplicity and automatism in the administration of computer networks. Recently, the DMTF which is a PBNM standards technology adapted to WBEM, DEN, and IETF is leading policy modeling. In the paper, We show a modeling and sharing of secure policy object-oriented and secured network administration by showing PBNM or reinforced LDAP (Lightweight Directory Access Protocol). Also, LDAP server is applied iPlanet and suggested the way of how to share network security information and LDAP schema. Tested to manage policy information stored in LDAP server by domain browser using Ponder toolkit that is PMT (Policy Management Tool).

유기용제 폭로 근로자의 자각증상에 관한 연구

엄영익,신혜련,우극현,안규동,이병국 순천향대학교 산업의학연구소 1997 순천향산업의학 Vol.3 No.1

To investigate the relationship of subjective symptoms of organic solvent exposed workers with their exposure level and urinary excretion of hippuric acid, 61 male workers who worked in 5 organic solvent using industries were studied. 89 workers were randomly selected from workers group for detailed health examination who visited hospital and had no exposure history to organic solvent as a control group. Personal air concentrations of organic solvent were checked for all organic solvent workers and urinary concentration of hippuric acid for both exposed and control group were also measured. Subjective symptom questionnaire of 31 organic solvent related item were provided to all workers and filled up by themselves and rechecked by medical doctor. The results obtained were as follows: 1. The overall prevalence rate of symptoms were significantly higher in exposed group than control group with statistical difference of 13 symptoms. 2. The overall prevalence rate of symptoms seemed to be increased by the exposure level of organic solvent. 3. The excretion of hippuric acid was more closely related to the level of toluene exposure than the level of mixed organic solvent exposure. 4. In the analysis of multiple stepwise regression using hippuric acid concentration as dependent variable and the concentration of each organic solvents as independent variables, only toluene had significant relationship with hippuric acid and none of other solvent did not affect on the concentration of hippuric acid. 5. In the analysis of multiple stepwise regression using symptom prevalence as dependent variable and the concentration of each organic solvents as independent variables, toluene had most significant effect to the symptom prevalence and the contribution of other solvents was minimal.

자율주행 운반체의 경로 계획

李基聖,신영국 弘益大學校 科學技術硏究所 2000 科學技術硏究論文集 Vol.11 No.-

In the path planning for a mobile robot, Distance Transform(DT), Certainty Grid Map and Artificial Intelligent algorithms are widely used. The above three algorithm have several drawbacks to generate the best path of all possible paths. In this paper new path planning algorithms are proposed. Three methods of path planning are Primitive Transform, Fast Primitive Distance Transform, Land Gambling Distance Transform. The simulation is performed to show that the proposed algorithms can generate the best path for a mobile robot.

비만세포주에서 Histamine 유리에 관한 연구

김형룡,국윤아,신민,이홍수,원진숙,김형민,이영미,정헌택,이혜숙,안녕형 원광대학교 생명공학연구소 1995 생명공학연구소보 Vol.3 No.1