• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권9호
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• pp.449-454
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• 2002

A rectangular straight microchannel, integrated with the resistance temperature detectors(RTDs) for temperature sensing and a micro-heater for generating the Temperature gradient along the channel, was fabricated. Its dimension is 57${\mu}{\textrm}{m}$(H)$\times$200${\mu}{\textrm}{m}$(W)$\times$48,050${\mu}{\textrm}{m}$(L), and RTDs were placed at the inner-channel wall. Si wafer was used as a substrate. For the fabrication of RTDs, 5300$\AA$ thick Pt/Ti layer was sputtered on a Pyrex glass wafer. Finally, the glass wafer was bonded with Si wafer by anodic bonding, so that the RTDs are located inside the microchannel. Temperature coefficient of resistance(TCR) values of the fabricated Pt-RTDs were 2800~2950ppm$^{\circ}C$ and the variation of TCR value In the range of O~10$0^{\circ}C$ was less than 0.3％. Therefore, it was proved that the fabricated Pt-RTDs without annealing were excellent as temperature sensors. The temperature distribution in the microchannel was investigated as a function of mass flow rate and heating power. The temperature increase rate diminished with decreasing the applied power and increasing the mass flow rate. It was confirmed from the comparison with the simulation results that the temperature measured inside the microchannel is more accurate than measuring the temperature measured at the outer wall. The proposed temperature sensing method and microchannel are expected to be useful in microfluidics researches.

• 척추신경추나의학회지
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• 제4권2호
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• pp.61-74
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• 2009

Objectives : The purpose of this study was to investigate the effect of chuna treatment(manipulation) on lumbar sprain caused by traffic accident in early stage, by analysis of the Heart Rate Variability(HRV) and Visual Analogue Scale(VAS). Methods : This study carried out on 20 patients who have received hospital treatment in Daejeon Univ. cheonan Oriental Hospital. Non-chuna group got acupuncture-therapy, herbal medication, physical therapy and Chuna group got all the therapies and chuna treatment. We measured HRV and VAS on 2nd, 4th day. Results : After being treated by our methods, Chuna group showed the inclination to balance between the sympathetic and parasympathetic nerve. In chuna group as compared with non-chuna group, an autonomic nerve activity and stress resistance showed the inclination to increase(p<0.05). And chuna treatment reduced the rate of stress increase. Conclusions : The results suggest that chuna treatment help traffic accident patients in early stage to reduce pain. Refer to autonomic nerve system, chuna treatment seem to do positive effect but Further long term study in a large scale is needed.

• 유기물자원화
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• 제23권1호
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• pp.45-51
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• 2015

본 연구에서는 비귀금속 촉매인 iron(II) phthalocyanine (FePc)와 cobalt tetramethoxyphenylporphyrin(CoTMPP)를 환원전극촉매로 이용하여 미생물연료전지의 연속운전을 진행하였다. 연속운전은 유기물 부하 (0.5~3 g COD/L/d)와 HRT (0.25~1 day)의 조건을 달리 운전하여 미생물연료전지의 성능을 평가하였다. 미생물연료전지의 전력밀도는 환원전극의 성능에 크게 영향을 받았으며, 최대전력밀도는 $3.3W/m^3$로 백금을 사용한 미생물연료전지에서 나타났다. 하지만, HRT의 조건을 달리 한 실험에서 FePc를 사용한 미생물연료전지가 백금을 사용한 미생물연료전지와 유사한 성능을 나타냈으며, 연속운전에서 백금 촉매를 대체할 수 있는 적합한 물질로 나타났다. 반면에 CoTMPP를 사용한 미생물연료전지는 연속운전에서 내부 저항의 급격한 증가로 전력밀도가 급격히 감소하였다.

• 한국지반공학회지:지반
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• 제12권3호
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• pp.17-34
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• 1996

본 논문의 주된 목적은 폐자원(첨가제로서 pyrolyzed carbon black과 굵을 골재로서 aircooled iron blast furnace slag)을 사용한 아스팔트 콘크리트의 기본특성을 설명하는 것이다. 최적의 아스팔트 함유량을 결정하기 위하여 Marshall Mik Design방법을 이용하였고, 최적의 아스팔트 함유량은 첨가제의 양에 따라 변하며,그 범위는 6.7%에서 7.57%로 나타났다. 최적의 아스팔트 함유량을 이용하여 아스팔트 콘크리트 시편을 제작하였고, dynamic creep 실험을 수행하였다. Pyrolyzed carbon black과 Furnace slag의 사용은 Marshall stability를 증가시켰고, 비교적 높은 온도(5$0^{\circ}C$)와 137.gkpa의 구속 압력하에서 아스팔트 콘크리트의 시간에 따른 변형률을 감소시켰고, 또한 시간에 따른 아스팔트 콘크리트의 stiffness감소 비율을 줄여주는 역할을 하였다. 본 실험결과로 부터 첨가제로서의 pyrolyzed carbon black과 굵은 골재로서의 slag의 사용은 Marshall stability, stiffness, rutting resistance에 좋은 결과를 나타내는 것으로 밝혀졌다.

• 한국어병학회지
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• 제10권1호
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• pp.45-52
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• 1997

단백질 결합 다당류인 PS-K가 Edwardsiella tarda의 감염에 대한 나일 틸라피아(Oreochromis niloticus)의 저항력 증강 효과에 대한 능력분석을 실시하였다. PS-K를 0.1 mg/g 어체중의 농도로 처리한 나일 틸라피아에 대하여 여러 농도외 E. tarda로 공격 실험을 하였다. 저농도($1.2{\times}10^7$ 그리고 $1.2{\times}10^8$ cfu/틸라피아)의 공격에 대하여 PS-K 처리구는 100% 생존율을 나타내었고 대조구는 각각 50%와 100%의 폐사율을 보여 주었다. 그러나 고농도의 E. tarda($1.2{\times}10^9$ 그리고 $1.2{\times}10^{10}$ cfu/틸라피아) 공격에 대해서는 약간의 수명 연장효과만 있었을뿐 대조구와 같이 100%의 폐사율을 보여 주었다. E. tarda($1.2{\times}10^7$ cfu/틸라피아) 공격 1주일 후 PS-K를 복강 투여한 나일 틸라피아는 100%의 생존율을 나타내었으나 대조구는 50% 생존율을 나타내어 PS-K가 가지고 있는 치료제로서의 잠재력을 보여 주었다. 그리고 PS-K 투여 1주일 후 주사된 E. tarda FKC에 대하여 보여준 나일 틸라피아의 높은 항체 반응은 PS-K가 어류의 특이 액성 면역반응에 관여하여 어류가 세균 감염시 높은 저항성을 갖게 하여 주는 것으로 나타났다.

• 한국수처리학회지
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• 제26권6호
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• pp.61-72
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• 2018

In this study, applicability of the decentralized water supply system were investigated by the high flux evaluation using ceramic membrane with combined pretreatment process. A) filtration process increased the transmembrane pressure of 1.4 kPa and 89.5 kPa on 2 and $5m^3/m^2{\cdot}d$ of filtration flux, respectively, the physical backwashing recovery rate were less than 28.6%. The (B) Coag./Floc. - Sedi. combined process with 4 mg / L of A-PAC showed that the transmembrane pressure increased to within 6 kPa, the physical backwashing recovery rate was over 37.9 % higher than (A) Filtration process. (C) Coag./Floc. combined process showed an increase of transmembrane pressure compared with (B) Coag./Floc. - Sedi. combined process, physical backwashing recovery rate was over 84%. As a result of the membrane fouling analysis using the resistance in series model, the combined pretreatment process showed that the cake resistance (Rc) was more than 92% at membrane filtration flux of $2m^3/m^2{\cdot}d$. In the (C) Coag./Floc. combined process, cake resistance(Rc) was over 86% on high flux conditions. The coagulation floc contained in influent was removed by the membrane, and the cake layer formed with the removed floc was identified as reversible fouling resistance which could be recovered by physical backwashing. The decentralized water supply system, which has the limitation of site area and installation space, is considered to could be operation of high flux of ceramic membrane by applying (C) Coag./Floc. combined process without sedimentation process.

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7303-7307
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• 2014

Objective: To explore the clinical efficacy of gemcitabine concomitant with nedaplatin and drug resistance in the treatment of non-small cell lung cancer (NSCLC) and associated molecular predicators. Materials and Methods: A total of 68 patients diagnosed with NSCLC by histology served as the study objects and were randomly divided into an observation group treated with gemcitabine concomitant with nedaplatin and a control group with cisplatin concomitant with gemcitabine, 34 cases for each group. Short-term and long-term efficacies, adverse responses as well as the expression of nucleotide excision repair cross complementing 1 (ERCC1), ribonucleotide reductase subunit M1 (RRM1) and lung resistance-related protein (LRP) in NSCLC tissues in both groups were assessed. Results: The short-term objective response rate (ORR) and disease control rate (DCR) were 35.3% (12/34) and 76.5% (26/34) in the observation group and 38.2% (13/34) and 85.3% (29/34) in the control group, respectively, the differences not being statistically significant. The time to progression (TTP) in both groups were 1~12 months, while the median TTP was 135 d and 144 d, respectively. Though the survival was slightly higher in the control group, there were no significant differences in TTP and survival time. The rates of decreased hemoglobin, vomiting and nausea as well as renal toxicity were evidently lower in the observation group, while other adverse responses demonstrated no significant difference. The positive expression rates of ERCC1, RRM1 and LRP were 47.1% (16/34), 61.8% (21/34) and 64.7% (22/34) in the observation group, respectively. Compared with negative ERCC1 expression, ORR had decreasing trend and the overall survival time (OS) decreased significantly in patients with positive ERCC1 expression, which were markedly decreased by the positive expressions of RRM1 and LRP. Conclusions: Gemcitabine concomitant with nedaplatin has significant effects in the treatment of NSCLC, with an adverse response rate obviously lower than for cisplatin concomitant with gemcitabine, suggesting that wider use in the clinic is warranted. Additionally, the positive expressions of ERCC1, RRM1 and LRP may increase patient drug resistance, so they can be applied as the chemotherapeutic predicators to guide individualized therapy of NSCLC patients.

• The Journal of Advanced Prosthodontics
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• 제1권2호
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• pp.85-90
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• 2009

STATEMENT OF PROBLEM. Over the years, resin-bonded fixed partial dentures (RBFPDs) have gone through substantial development and refinement. Several studies examined the biomechanics of tooth preparation and framework design in relation to the success rate of RBFPDs and considered retention and resistance form essential for increase of clinical retention. However, these criteria required preparations to be more invasive, which violates not only the original intentions of the RBFPD, but may also have an adverse effect on retention due to loss of enamel, an important factor in bonding. PURPOSE. The object of this in vitro study was to compare the dislodgement resistance of the new types of RBFPDs, the conventional three-unit fixed partial denture, and conventional design of RBFPD (Maryland bridge). MATERIAL AND METHODS. Fifty resin mandibular left second premolars and second molars were prepared on dentiforms, according to the RBFPD design. After model fabrication (five group, n = 10), prostheses were fabricated and cemented with zinc phosphate cement. After cementation, the specimens were subjected to tensile loading at a cross head speed of 4 mm/min in a universal testing machine. The separation load was recorded and analyzed statistically using one-way analysis of variance followed by Duncan's multiple range test. RESULTS. Group V, the pin-retained RBFPDs, had the highest mean dislodgement resistance, whereas specimens of group II, the conventional RBFPDs, exhibited a significantly lower mean dislodgement resistance compared to the other 4 groups (P <.05). There were no significant differences between group I, III, and IV in terms of dislodgement resistance (P>.05). Group V had the highest mean MPa (N/$mm^2$) (P <.05). There was no significant difference between groups I, II, III and IV (P > .05). CONCLUSION. Within the limits of the design of this in vitro study, it was concluded that: 1. The modified RBFPDs which utilizes the original tooth undercuts and requires no tooth preparation, compared with the conventional design of RBFPDs, has significantly high dislodgement resistance (P < .05). 2. The modified RBFPDs which utilizes the original tooth undercuts and requires minimal tooth preparation, compared with the conventional FPDs, has significantly no difference in retention and dislodgement resistance)(P>.05). 3. The pin-retained FPDs showed a high dislodgement resistance compared to the conventional three-unit FPDs (P<.05).

• 콘크리트학회논문집
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• 제23권5호
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• pp.551-558
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• 2011

경량 골재 콘크리트의 역학적 특성에 대한 천연모래 치환율과 경량 굵은 골재 최대 크기의 영향을 평가하기위해 15배합의 실험이 진행되었다. 경화된 경량 골재 콘크리트의 공극률 및 기건 단위 질량, 재령에 따른 압축강도 발현, 인장저항성능, 탄성계수, 파괴계수 및 응력-변형률 관계를 측정하였다. 측정된 역학적 특성들은 ACI 318-08, EC2 및 CEB-FIP 기준 또는 Slate 등, Yang 등 및 Wang 등의 제안모델들과 비교하였다. 실험 결과 경량 골재 콘크리트의 압축강도는 굵은 골재 최대 크기가 클수록 그리고 경량 잔골재 양이 증가할수록 감소하였다. 경량 골재 콘크리트의 압축강도 발현에 대한 상수는 굵은 골재의 비중과 천연모래 치환율의 함수로서 제시될 수 있었다. 한편, 측정된 경량 콘크리트의 파괴계수 및 인장강도는 설계기준 및 제안모델들에 비해 일반적으로 낮았는데, 이는 경량 콘크리트의 인장저항성은 압축강도뿐만 아니라 기건 단위 질량에 의해서도 영향을 받기 때문이다.

• 한국농공학회지
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• 제20권2호
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• pp.4645-4687
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• 1978

This study was attempted to investigate the mechanical properties of concrete and crack control effects of reinforced concrete with steel and glass fiber. The experimental program includes tests on the properties of fresh concrete containing fibers, compressive strength, tensile strength, flexural strength, Young's modulus, Shrinkage and deformation of steel or glass fiber reinforced concrete. Also this study was carried out to investigate the effect of steel or glass fiber to retard the development in reinforced concrete subject to uniaxial tension and thus facilitate the use of steels of higher strength. The major conclusions that can be drawn from the studies are as follows: 1. The effect of the fibers in various mixes on fresh concrete confirmed that fibers do have a significant effect on the properties of fresh concrete, bringing much more stable and exhibiting a signiflcant reduction in surface bleeding, and that the cohesion is greatly improved and the internal resistance increases with fiber concentration. But the addition of an excess contents and length of fibers brings about the reduction of workability. 2. With the addition of steel fibers(1.5% Vol.) to concrete, the compressive strength as compared with plain concrete showed a very slight increase, but excess addition, over 1.5% Vol. of steel and glass fiber reduced its strength. 3. Splitting tensile strength of fiber reinforced concrete showed a significant increase tendency, as compared with plain concrete. In case of containing steel fiber (2.5%, 30mm), it showed that the maximum increase rate of 1.48 times as much rate, and in case of containing glass fiber (2.5%, 30mm), the increase rate of strength was 1.25 times as much rate. 4. Flexural strength of fiber reinforced concrete showed a significant tendency, as compared with plain concrete. Containing steel fiber (2.5%, 30mm) showed the maximum increase rate of 1.64 times as much rate and containing glass fiber (2.5%, 30mm) showed the increase rate of strength of 1.32 times as much rate, and in general, the 30mm length brougth the best results. 5. The strength ratio ($\sigma$b/$\sigma$c and $\sigma$t/$\sigma$c) increased, when steel fiber's average spacing was up to 3.05mm, but decreased when beyond 3.05mm, and it was confirmed that tensile or flexural strengths of steel fiber reinforced concrete are apparently governed by fiber's average spacing. 6. The compressive strain of fiber reinforced concrete showed a significant increasing tendency as the fiber was added, but Young's modulus. with the addition of steel and glass fibers, showed a slight decrease tendency. And according to the increase of flexural strength, a considerable increase was seen in toughness. 7. With the addition of fiber's the shrinkage of concrete was significantly decreased, in both case of adding steel fibers 12.5%, 30mm, and showed a significant decrease ratio, in average 30.4% and 36.7%, as compared with plain concrete. 8. With the increase of fiber volume fraction and length, the gained stress in reinforcing bar in concrete specimens increased in all crack widths, but at different rates, with the decrease of fiber diameter, the stress showed a considerable increasing tendency. And the duoform steel fibers showed the greatest improvement, as compared with the other types tested. 9. The influence of fiber dimensions in order of significanse on the machanical properties of concrete and the crack control of reinforced concrete was explained as follows: content, length, aspect ratio and dimeter.