기어加工用 챔퍼링머신의 構造解析

權赫洪,金善浩 대진대학교 1994 大眞論叢 Vol.2 No.-

In this study the structure analysis of chamfering m/c is developed to improve dynamic characteristics To this purpose a chamfering m/c is mathematically modelled and dynamic response analysis of the model are investigated by use of Finite Element Method(FEM). The investigation procedures are as follows. The finite element modelling of the chamfering m/c is done with triangular and rectangular plate elements and each node of the elements has 6 degrees of freedom. And this model is idealized as a forced vibration system under impulse load by cutting force Model parameters, natural frequency and mode shape, and dynamic response for displacement and stress are analyzed by use of mode superposition method. To reduce computing time of dynamic response analysis, lower vibration mode is analyzed with master-DOF and mass participation factor. In this case maximum relative displacement is occured at 17.483 Hz in the right column. this result

壓縮코일스프링의 設計自動化

권혁홍,최선준 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.6

Springs for vehicle suspension control the vibration of a car and influence on the ridability, safety, and life of a car. In the paper, the computer aided design program has been developed, which design the leaf spring shape from the given spec-ifications using basic theory and the expert's knowledge, and the design results arc checked by the analysis theory in order to increase the accuracy, and feed back to the design input. For the purpose of easy use, this program consists of pull-down menu and interactive input mode. To prove the effec-tiveness of this program, two springs, of which one is symmetric, other asymmetric, arc designed and analyzed, and the outputs are compared to the experiments. Considering the tolerance of the given specifications, the results are good.

원주 법천리출토 금동식리에 대한 연구

권혁남,유혜선 국립중앙박물관 2001 박물관보존과학 Vol.3 No.-

Scientific analysis are carried on gilded ornamental shoes, which have been excavated from tomb No 1. and No 4. in Beopcheon-ri, Wonju dated from Baekje Period. This object is a very important because it provides valuable information on the development of metal-making techniques of that period. Thus, this article illustrates the investigation conducted to reveal how the object was created using what materials and techniques. Instead of the spikes-attached to the bottom plate of the object-that couldn't be sampled, a sample of a decorative rivet showing a similar structure to the spikes-attached to the other parts of the shoes-was prepared for a cross-section examination. Using radiography and microscopes, it was found that the head of a spike was placed and then punched to the gilded plate, so it can be held to the shoes. Under the SEM-EDS, the cross-section of the rivet shows that the gilding layer was applied before the attachment of the rivets. It also shows that the gilding layer is distributed unevenly and there are empty spaces indicating amalgam gilding was employed. This was confirmed as Mercury was detected on the SEM-EDS analysis of the object. The examination of the microstructure of the plate using the SEM-EDS revealed that the object is made of a single copper alloy plate with recrystallized twining and non metallic white inclusions, which found to be lead in this case. 백제 문화의 중요한 자료가 되고 있는 원주 법천리 고분군 중 1호분과 4호분에서 금동식리편이 발굴되었다. 특히 이 식리에는 스파이크가 존재하여 백제의 식리 제작과 금동 기술에 대한 정보를 제공할 수 있다. 본 연구는 이곳에서 출토된 식리편을 분석하여 식리의 제작 방법, 당시 사용된 동의 특성 등을 조사하였다. 스파이크는 투과X-선과 현미경 등을 통해 관찰해 본 결과 하나의 몸체로 제작되어 머리 부분을 두드려 금동판에 부착하였다. 이 금동판은 대부분 구리로 되어 있으며 재결정에 의한 쌍정이 나타나고 있고, 비금속 개재물의 EDS 분석 결과 납을 함유하고 있다. 또한 금동판이 두 개로 되어있다는 증거가 나타나지 않아 장식용으로 리벳을 사용한 것으로 보인다. 금동판의 도금은 금도금층의 두께가 불균일하고 내부가 비어 있으며 EDS 분석에서 수은이 검출되는 것으로 보아 아말감법에 의한 도금을 하였다.

박판스프링 교정시스템 구축에 관한 연구

권혁홍,김선호 대진대학교 1997 大眞論叢 Vol.5 No.-

This paper describes that study which construct a theoretic and experimental algorithm in order to make the automatic correction system of detent spring, and when load for correction pressed at spring, it can be found elastic and plastic deformation quantities by Finite Element Analysis. As a result, it has been found that the simulation datas are in good agreement with experimetal results.

국내 살모넬라 분리주에서 spvR 유전자 분포와 단일 뉴클레오티드 다형 연구

권혁준,박경윤,박주연,박용호,김선중,유한상 대한감염학회 2004 감염과 화학요법 Vol.36 No.6

목적 : 지금까지 병원성 살모넬라를 확인하기 위해 분자량이 큰 플라스미드의 존재 유무를 확인하여 왔으나 살모넬라 혈청형 및 검출 방법에 따라 양성율에 큰 차이를 보이고 있고, 일부 병원성 살모넬라 분리주에서 병원성 플라스미드가 관찰되지 않아 spv 유전자들의 유무에 대한 아른 확인방법이 필요하다. 본 실험은 국내 동물 유래 주요 살모넬라 혈청형에서 spvR 유전자의 분포를 알아보고, 병원성 살모넬라 분자진단을 위한 분자표지로써의 가치를 평가하기 위해 실행하였다. 재료 및 방법 : 국내 가축 유래 S. lyphimurium (ST, 26주), S. enteritidis (SE, 10주), S. pullorum (SP, 40주), S. gallinarum (SG, 53주)에 대해 GenBank에 등록된 ST, SE, SP의 spvR 유전자를 비교하여 ST와 SE 간에 차이를 보이는 single nucleotide polymorphism (SNP, 625번 뉴클레오티드)을 포함하도록 시발자를 합성하여 집락-PCR을 수행하였다. 증폭 산물(194bp)은 자동 염기서열장치를 이용하여 염기서열을 결정하였고, 제한효소인 MseI을 사용하여 PCR-RFLP를 실시하였다. 결과 : 집락-중합효소연쇄반응 결과 SP, SG, SE의 모든 (100%) 분리주에서 특이 증폭산물이 검출되었으나 ST의 경우 19주(73%)에서만 증폭되었다. 특히 병원성 관련 플라스미드가 관찰되지 않았던 SP 4주에서 특이적인 증폭산물이 검출되었다. 염기서열 분석결과 SE, SG, SP는 625번 뉴클레오티드에 아데닌을, ST는 구아닌을 가지고 있어 PCR-RFLP를 이용하여 쉽게 구분할 수 있었다. 결 론 : spvR에 대한 집락-중합효소연쇄 반응법은 병원성 플라스미드 검출법보다 SE, SP, SG 병원성 주를 신속하게 검출하는데 유용하고, 625번 뉴클레오티드의 SNP는 ST와 SE, SG, SP를 구분하는 분자표지로 사용될 수 있을 것으로 기대되며, ST에 비해 SE는 진화적으로 SG와 SP에 가까운 것으로 생각되었다. Background : The Salmonella virulence plasmid (spv) genes (spvR, A, B, C and D) on the large virulence plasmids of pathogenic Salmonella serotypes can replace the virulence of the whole plasmid. Recently, virulence plasmid-negative pathogenic Salmonella isolates were isolated. However, positive rates of spv genes among Korean Salmonella serotypes have been obscure. spv genes are conserved in compared to other virulence genes but there are single nucleotide polymorphisms (SNPs) conserved in only certain serotype. Such SNPs are useful for differentiation and understanding evolution of certain serotypes. Materials and Methods : Salmonella serotypes isolated from live stocks [Salmonella typhimurium (ST, 26), S. enteritidis (SE, 10), S. gallinarum (SG, 40) and S. pullorum (SP, 53)] were used for colony-PCR. A primer set covering single nucleotide polymorphism (SNP) at 625th nucleotide of spvR was designed. The nucleotide sequences of amplicons were determined by cyclic sequencing method and RFLP was performed by using MseI. Results : All isolates of SE, SG and SP, including four plasmid-negative isolates, showed specific amplicons but not all of ST (19/26, 73%) were positive to spvR. Based on the nucleotide sequence of 625th nucleotide and PCR-RFLP, SE, SG and SP [A(625)] and ST [G(625)] could be differentiated. Conclusion : spvR can be used as a molecular marker to detect virulent SE, SG, SP and the SNP may be useful for differentiation of SE, SG, SP and ST. According to the SNP study SE may be evolutionarily closer to SG and SP than ST.

여재의 개선에 따른 유기물 제거효율 및 질산화 비교

민선홍,김병욱,권재혁 三陟大學校 2000 論文集 Vol.33 No.2

Where control of algal growths in the receiving water is necessary to protect beneficial uses, removal or reduction of nitrogen in wastewater prior to charge may be desirable. An object of this study is development of nitrification(conversion TKN to nitrate) rate in domestic wastewater treatment. A bench scale reactor used in this study has reused media(SWPP media). This study was conducted to investigate the performance and bioflim characteristics of modified media(RUN 2) in comparison with conventional media(RUN 1) on wastewater treatment system. Influent BOD, COD and TKN concentration were ranged 254.1 to 270.4 mg/L, 473.0 to 498.4 mg/L and 19.3 to 21.4 mg/L, respectively. During operating time for 116 day, organic loading rates were 0.254 to 1.044 kgBOD/㎥/day and nitrogen loading rates were 19 to 86 gTKN/㎥day. The results were as follows ; Nitrogen removal efficiency was 22.3, 36.1, 90.4 and 95.8% in RUN 1 and 25.2, 75.1, 95.1 and 96.7% in RUN 2. Effluent NO₃-N concentration in RUN1 and RUN2 were 0∼15.54mg/L, 0.09∼15.99 mg/L, respectively.

Al-Si합금용탕과 Al₂O₃의 젖음성에 관한 연구

朴昌宣,金鍾贊,朴相俊,權赫茂 忠南大學校 産業技術硏究所 1992 산업기술연구논문집 Vol.7 No.1

The purpose of this study is to obtain basic infotmation on the wettability of pure-Al/Al₂O₃, Al-alloy/Cu, Al-alloy/Ni and Al-12%Si/Al₂O₃systems, by using the Sessile drop method. The wettability of Al alloy-melt on Al₂O₃increases with increasing temperature from 750℃ to 850℃ for Al-12%Si-y% (Cu, Zn and Mg) (y:0∼2)/Al₂O₃system, the contact angle decreases with increasing Cu, Zn and Mg content. The wettability of Al alloy on Cu and Ni-palte is better than that on Al₂O₃-plate : this is attributed to the interfacial reaction between the Al aiioy and the metal substrate.

상온재생 유화아스팔트 개질 혼합물의 배합방법 및 특성에 관한 실험적 연구

박승범,권혁준,이봉춘,김선용 충남대학교 산업기술연구소 1999 산업기술연구논문집 Vol.14 No.2

Recently, the quantities of waste asphalt concrete at construction sites have much increased greatly, but maintaining a filling-up and final disposal place is a difficult problem. Therefore, we are faced with a worsening environmental problem brought about present illegal measures. One of the most effective recycling method is cold recycling. This method will satisfies treatment and recycling of construction waste is a very important question in the preservation of environmental and natural resources. So, in this paper, we dealt cold recycling modified mixtures using emulsified asphalt to concern the effect of adding reclaimed asphalt concrete 30, 40, 50%, and using SBR Latex for modified mixtures.

급성 심근경색증을 동반한 혈전성 혈소판 감소성 자반증 1예

이태희,김진혁,김완중,박지영,강흥선,조정휘,김권삼,송정상,배종화 대한순환기학회 2003 Korean Circulation Journal Vol.33 No.11

브로콜리 추출물의 향장활성 효과

김대용ㆍ조석철ㆍ권혁선ㆍ김미경(Dae Young KimㆍSeok chul ChoㆍHyuk sun KwonㆍMee Kyung Kim) 한국인체미용예술학회 2016 한국인체미용예술학회지 Vol.17 No.1

In this study, we investigated the anti-oxidative effects, antimicrobial, and anti-inflammatory activities of the extracts from broccoli to evaluate its use as a functional ingredient in cosmetics. The extracts are WE (water extract at RT), MWE (mineral water extract at RT), EE (70% ethanol extract at RT), and USEE (heat process for 12 hours at 60℃ after ultrasonification for six hours with 70% ethanol). The measurements of the total polyphenol content from broccoli extracts were highest in EE at 425.24±13.9 mg/g dry. The result of electron donating ability of EE was the highest at 10,000 ㎍/㎖ as 97.81% and increased in a concentration-dependent manner. The ferric reducing antioxidant powder (FRAP) of EE was the highest at 10,000 ㎍/㎖ as 1235.6 μM. In an antimicrobial activity test, the EE showed significant antimicrobial activity against S. epidermidis, S. aureus, E. coli, P. acnes, and P. ovale. Furthermore, broccoli extract exhibited no cytotoxicity in RAW 264.7 cells. Also anti- inflammatory activity by NO assay showed LPS-induced NO was significantly inhibited following treatment with EE of 1,000 ㎍/㎖. Therefore, the broccoli ethanol extract can be used as a resource of natural cosmetic material for functional cosmetics.