• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.60-60
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• 2017

화석연료의 고갈과 환경오염이 문제시 되면서 친환경 에너지개발에 대한 연구가 진행되고 있다. 그중 바이오디젤은 동,식물성유지 및 폐식용유를 이용하여 생산이 가능할뿐더러 농용엔진에 특별한 개조 없이 사용가능하다. 또한 바이오디젤 자체에 산소를 함유하고 있어 이산화탄소 저감에 효율적이다. 바이오 디젤에 관한 많은 연구가 수행되었으며, 기존의 연구는 단일유지의 폐식용유를 사용하여 바이오디젤을 생산하는 연구가 진행되었다. 하지만 가정에서 배출되는 식물성 폐식용유의 경우 여러 가지가 혼합되어 배출되고 있어, 혼합폐식용유지의 바이오디젤 특성평가가 필요하다. 따라서 본 연구에서는 폐식물성유지(폐대두유, 폐카놀라유, 폐해바라기유)를 중량비(1:4, 1:1.5 1:0.66, 1:0.25)로 혼합하여 바이오디젤을 생산하고, 생산한 바이오디젤을 농용기관에 이용하여 농용기관의 출력특성 및 배기배출물특성 평가를 실시하였다. 실험에 사용된 농용기관은 배기량이 673cc인 직접분사식 디젤기관(ND10DE, Daedong, Korea)이며, 엔진성능평가를 위해 토크는 토크센서(YDL-704s, Setech, Korea)를 사용하였다. 배기배출물 평가는 배기가스분석기(HG-550, Airlex, Germany)를 이용하여 이산화탄소, 질소산화물을의 배출량을 측정하였다. 폐식용유를 이용하여 생산한 바이오디젤과 경유의 기관성능을 비교한 결과 토크와 축출력의 경우 BD의 혼합량이 증가할수록 줄어들었다. 토크는 혼합된 유지에 따라 상용운전범위인 1500rpm~2400rpm에서 평균 대두와 카놀라유를 혼합하여 생산한 BD10은 7.2%, BD20은 12.1% 감소하였고, 대두와 해바라기유를 혼합하여 생산한 BD10은 11.3% BD20은 16.3% 감소하였다. 또한 해바라기와 카놀라유를 혼합하여 생산한 BD10은 8.3%, BD20은 14.6% 감소하였다. 이는 BD의 발열량이 경유에 비해 낮아 토크가 감소한 것으로 판단된다. 또한 배기배출물 평가의 경우 질소산화물은 BD의 함랑이 증가함에 따라 경유에 비해 배출량이 증가하는 경향을 보였고, 이산화탄소는 저감되는 것으로 나타났다. 이는 바이오디젤이 함산소연료이므로, 연료내의 산소로 인해 완전연소를 촉진시켜 이산화탄소를 저감시키고 질소산화물은 증가된 것으로 판단된다.

• Journal of the Korean Ceramic Society
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• v.32 no.4
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• pp.507-515
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• 1995

The monolithic dry gels of the Li2O-Al2O3-TiO2-SiO2 system were prepared by the sol-gel technique using metal alkoxides as starting materials to obtain monolithic glass-ceramics at low temperature without melting. Activation energy for the crystal growth of the gel with 6.05% TiO2, nucleating ageng, for the preparation of Li2O-Al2O3-TiO2-SiO2 system glass-ceramic was 101.14kcal/mol. As a result of the analysis of DTA & XRD, it was confirmed that the crytallization of Li2O-Al2O3-TiO2-SiO2 system glass-ceramic was the most efficient when 6.05% TiO2, nucleating agent, was added. $\beta$-eucryptite solid solution crystals and $\beta$-spodumene solid solution crystals were detected in the sample heat treated above 85$0^{\circ}C$. The sintered gel heat treated at 85$0^{\circ}C$ had the specific surface area of 185$m^2$/g, the pore volume of 0.19cc/g and the average pore radius of 20.8$\AA$. This shows that the sintered gel is also comparatively porous material. In temperature range of 25~85$0^{\circ}C$ thermal expansion coefficient of the specimen which was crystallized for 10hrs at 85$0^{\circ}C$ was 6.7$\times$10-7/$^{\circ}C$, which indicated that the crystallized specimen was turned out to be the glass-ceramic with low thermal expansion.

• Journal of the Korean Data and Information Science Society
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• v.19 no.3
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• pp.937-949
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• 2008

The purpose of this meta-analysis was to investigate the anti-hepatotoxic effect of ginseng in rats induced with CC14 or TCDD, the toxicities that cause liver damages. Primary studies were collected from the ScienceDirect database, the DBpia, and the KISS. The data on the effect factors in plasma and in enzyme are listed as many as possible: The effect factors were alanine transaminase(ALT), aspartate transaminase(AST), liver aminopyrine N-demethylase(AD), liver aniline hydroxylase(AH), liver 3,4-Methylenedioxyamphetamine(liver MDA), cytochrome P450(P450), serum alkaline phosphatase(ALP), serum lactate dehydrogenase(LDH), cytochrome b5(Cyto b5), glutathione reductase (GR), Liver glutathione S-transferase(GST), liver glutamyltransferase (GT), Liver($\gamma$-GCS), serum liver 3,4-Methylenedioxyamphetamine(serum MDA), serum sorbitol dehydrogenase(SDH), serum total protein(TP), and serum $\gamma$-glutamyltransferase($\gamma$-GT). In order to investigate the effect of ginseng, the standard mean difference(HG) between the group of rats induced with toxicity(RH) and the group of rats induced with ginseng(RHG) were combined, and the significance of HGs were tested. The combined HGs checked the biases caused by heterogeneity among studies and the publication biases. Then they were adjusted by using the random effect model and trim and fill method. Although the publication biases were assumed, among all plasma factors the HGs of ALT, AST, serum MDA, SDH, TP, and $\gamma$-GT were significant, and among all enzyme factors the HGs of liver MDA, Cyto b5, GR, GST, and GT were significant. The treatment with ginseng significantly affected the plasma and enzyme levels in rats induced with toxicity.

• Journal of Korean Neurosurgical Society
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• v.41 no.3
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• pp.157-160
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• 2007

Objective : The purpose of this study was to evaluate the efficacy and safety of the surgical treatment for lumbar spinal stenosis in elderly patients. Methods : The authors reviewed the medical records of 49 patients older than 65 years of age with lumbar spinal stenosis who underwent surgical treatment from January 2002 to December 2004 in our institute. Results : Average age of patients was 70 years old [32 women, 17 men]. Twenty-four patients had chronic medical disorders. All patients were operated under the general anesthesia of these, 29 patients underwent decompressive laminectomy and decompressive laminectomy with instrumentation and fusion in 20 patients. The mean operation time was 193.5 minutes, mean estimated blood loss was 378cc and mean postoperative hospital stay length was 15.3 days. The mean follow-up duration was 11.9 months. The evaluation of outcome was assessed by Macnab classification. At first month after operation, the outcome showed excellent in 7 [14.3%]. good in 35 [71.4%], fair in 5 [10.2%], and poor in 2 [4.1%]. And at 6 months after operation, 17 patients were lost in follow-up, the outcome showed excellent in 4 [12.5%], good in 25 [78.1%], fair in 3 [9.4%], and no poor cases. There was no significant difference between outcome of laminectomy alone and that of laminectomy with fusion. Six patients [12.2%] experienced postoperative complications which included wound infection [3], nerve root injury [1], disc herniation [1], and reoperation due to insufficient decompression [1]. There were no deaths related to operation. Conclusion : We conclude that the surgical treatment for lumbar spinal stenosis in elderly patients can provide good results with acceptable morbidity when carefully selected. In addition, decision on lumbar spinal fusion should not be against solely on advanced age.

• Korean Journal of Oriental Medicine
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• v.14 no.1
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• pp.137-143
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• 2008

In this research, as a method for verifying the efficacy of Ssangwhatang and fungus-fermentated Ssangwhatang, a comparative study on the liver protection effect was conducted using animal experiments by inducing the liver toxicity with the $CC_{l4}$ treatment. Inducing the liver damage resulted in the increase in the serum AST and ALP activity, and one day administration of the test material($CCI_4$: 0.5 ml/kg/day) caused 520 IU/L of the ASP activity leading to 29% enhancement in comparison with the normal group and 93% and 81% reductions in the fungus-fermentated Ssangwhatang-administered groups, BFST1 and BFST2, respectively. ALT is 42 IU/L for the normal group and 99 IU/L for the negative control group leading to 135% enhancement. 15 ml/kg/day and 30 ml/kg/day administrations of fungus-fermented Ssangwhatang(BFST) resulted in 51% and 45% decreases in the ALT concentration, respectively. One day administration of 30 ml/kg Ssangwhatang and fungus-fermentated Ssangwhatang caused the LDH in the plasma to tend to decrease. $CCI_4$(1.0 ml/kg/day) administered at the 0th and 4th days led to the observation of the tendency toward the decrease in AST, ALT, and LDH contents. The results indicate that the function of Ssangwhatang is partly reinforced under the fungus-fermentated Ssangwhatang performed in order to verify the efficacy of Ssangwhatang' s effect on the recovery from fatigues.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.952-964
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• 2005

The diesel-degrading activities of biofilms sampled from petroleum-contaminated groundwaters in urban subway drainage systems were examined in liquid cultures, and the microbial populations of the biofilms were characterized by denaturing gel gradient electrophoresis (DGGE) and 16S rDNA sequence analysis. Biofilm samples derived from two sites (19 K and 20 K) at subway Station N and Station I could degrade around $80\%$ of applied diesel within 20 and 40 days, respectively, at $15^{\circ}C$, and these results were strongly correlated with the growth patterns of the biofilms. The closest phylogenetic neighbor of a dominant component in the 19 K biofilm was Thiothrix fructosivorans strain Q ($100\%$ similarity). Four dominant strains in the 20 K biofilm were closely related to Thiothrix fructosivorans strain Q ($100\%$ similarity), Thiothrix sp. CC-5 ($100\%$ similarity), Sphaerotilus sp. IF14 ($99\%$ similarity), and Cytophaga-Flexibacter-Bacterioides (CFB) group bacterium RW262 ($98\%$ similarity). Three dominant members in the Station I biofilms were very similar to uncultured Cytophagales clone CRE-PA82 ($91\%$ similarity), Pseudomonas sp. WDL5 ($97\%$ similarity), and uncultured CFB group bacterium LCK-64 ($94\%$ similarity). The microbial components of the biofilms differed depending on the sampling site. This is the first report on the isolation of clones highly similar to Thiothrix fructosivorans and Thiothrix sp. from biofilms in petroleum-polluted groundwaters, and the first evidence that these organisms may play major roles in petroleum degradation and/or biofilm-development.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2917-2922
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• 2014

Background: The p53-binding protein 1 (TP53BP1) gene may be involved in the development of cancer through disrupting DNA repair. However, investigation of associations between TP53BP1 rs2602141 A/C polymorphism and cancer have yielded contradictory and inconclusive outcomes. We therefore performed a meta-analysis to evaluate the association between the TP53BP1 rs2602141 A/C polymorphism and cancer susceptibility. Materials and Methods: Published literature from PubMed, Medline, the Cochrane Library, EMbase, Web of Science, Google (scholar), CBMDisc, Chongqing VIP database, and CNKI database were retrieved. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using fixed or random-effects models. Publication bias was estimated using funnel plots, Begg's and Egger's test. Results: A total of seven studies (3,018 cases and 5,548 controls) were included in the meta-analysis. Our results showed that the genotype distribution of TP53BP1 rs2602141 A/C was not associated with cancer risk overall. However, on subgroup analysis, we found that TP53BP1 rs2602141 A/C was associated with cancer risk within an allele model (A vs C, OR=1.14, 95%CI: 1.01-1.29) and a codominant model (AA vs CC, OR=1.36, 95%CI: 1.06-1.74) in Asians rather than in Caucasians. Subgroup analysis by cancer type, genotype, and with or without adjustment for controls showed no significant association. Conclusions: The findings suggested an association between rs2602141 A/C polymorphism in TP53BP1 gene and increased risk of cancer in Asians.

• Journal of Korean Neurosurgical Society
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• v.42 no.1
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• pp.6-10
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• 2007

Objective : The purpose of this study was to determine the effect of bone cement augmentation of pedicular screwing in severe osteoporotic spondylolisthetic patients. Methods : Twenty patients with spondylolisthesis (8 : spondylolytic spondylolisthesis 12 : degenerative spondylolisthesis) who had undergone pedicular screwing and interbody fusion for osteoporotic lumbar spine (T-score on bone mineral density<-3.0) from 2002 to 2005 were reviewed. Mean age was 62.3 years with 3 male and 17 female patients. Average follow-up period was 14 months. Average T-score on bone mineral density (BMD) was -3.62. After decompression of neural elements, about 6cc of polymethylmethacrylate (PMMA) was injected into the each vertebral body through transpedicular route. All patients underwent one level interbody fusion and pedicular screw fixation. Clinical outcome was assessed using Oswestry Disability Index (ODI) on the last clinical follow-up. In addition, a modified MacNab's grading criteria was used to objectively assess patient's outcome postoperatively. Radiographic analysis of sagittal contour was assessed preoperatively, immediately postoperatively, and at final follow-up including fusion rate. Results : Eighteen of 20 patients were graded as excellent or good according to the modified MacNab's criteria. An significant improvement of ODI was achieved in both groups. Mean sagittal angle at the preoperative state, postoperative state and at the last follow-up state was $11.0^{\circ},\;20.1^{\circ}$ and $18.3^{\circ}$, respectively, with mean sagittal angle correction gain $7.3^{\circ}$. Firm fusion was achieved in all patients. There were one compression fracture above the fused segment after 6 months follow-up and one case of seroma. But there were no postoperative complications related to bone cement leakage and pedicular screwings such as screw pullout or screw cut-up. Conclusion : Bone cement augmentation of pedicular screwing can be an effective procedure for osteoporotic lumbar spine in spondylolisthetic patients.

• Journal of Korean Neurosurgical Society
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• v.44 no.6
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• pp.358-363
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• 2008

Objective : This study was performed to assess the efficacy of GKS in patients with ten or more brain metastases. Methods : From Aug 2002 to Dec 2007, twenty-six patients (13 men and 13 women) with ten or more cerebral metastatic lesions underwent GKS. The mean age was 55 years (32-80). All patients had Karnofsky performance status (KPS) score of 70 or better. According to recursive partitioning analysis (RPA) classification, 3 patients belonged to class I and 23 to class II. The location of primary tumor was lung (21), breast (3) and unknown (2). The mean number of the lesions per patient was 16.6 (10-37). The mean cumulated volume was 10.9 cc (1.0-42.2). The median marginal dose was 15 Gy (9-23). Overall survival and the prognostic factors for the survival were retrospectively analyzed by using Kaplan Meier method and univariate analysis. Results : Overall median survival from GKS was 34 weeks (8-199). Local control was possible for 79.5% of the lesions and control of all the lesions was possible in at least 14 patients (53.8%) until 6 months after GKS. New lesions appeared in 7 (26.9%) patients during the same period. At the last follow-up, 18 patients died; 6 (33.3%) from systemic causes, 10 (55.6%) from neurological causes, and 2 (11.1 %) from unknown causes. Synchronous onset in non-small cell lung cancer (p=0.007), high KPS score (${\geq}80$, p=0.029), and controlled primary disease (p=0.020) were favorable prognostic factors in univariate analysis. Conclusion : In carefully selected patients, GKS may be a treatment option for ten or more brain metastases.

• Journal of Korean Neurosurgical Society
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• v.50 no.3
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• pp.179-184
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• 2011

Objective : The aim of this study is to evaluate the therapeutic effects of gamma knife radiosurgery (GKRS) in patients with multiple brain metastases and to investigate prognostic factors related to treatment outcome. Methods : We retrospectively reviewed clinico-radiological and dosimetric data of 36 patients with 4-14 brain metastases who underwent GKRS for 264 lesions between August 2008 and April 2011. The most common primary tumor site was the lung (n=22), followed by breast (n=7). At GKRS, the median Karnofsky performance scale score was 90 and the mean tumor volume was 1.2 cc (0.002-12.6). The mean prescription dose of 17.8 Gy was delivered to the mean 61.1% isodose line. Among 264 metastases, 175 lesions were assessed for treatment response by at least one imaging follow-up. Results : The overall median survival after GKRS was $9.1{\pm}1.7$ months. Among various factors, primary tumor control was a significant prognostic factor ($11.1{\pm}$1.3 months vs. $3.3{\pm}2.4$ months, p=0.031). The calculated local tumor control rate at 6 and 9 months after GKRS were 87.9% and 84.2%, respectively. Paddick's conformity index (>0.75) was significantly related to local tumor control. The actuarial peritumoral edema reduction rate was 22.4% at 6 months. Conclusion : According to our results, GKRS can provide beneficial effect for the patients with multiple (4 or more) brain metastases, when systemic cancer is controlled. And, careful dosimetry is essential for local tumor control. Therefore, GKRS can be considered as one of the treatment modalities for multiple brain metastase.