탄소나노튜브/그래핀 기반의 1차원 나노구조체 합성 및 나트륨이온 저장특성평가

김수연, 권중인, 조중상 충북대학교 산업과학기술연구소 2018 산업과학기술연구 논문집 Vol.32 No.2

본문 참조

유아용 언어학습지에 대한 내용 분석

원중연 천안대학교 2001 천안외국어대학논문집 Vol.- No.1

As the educating activities for pre-school children are recently getting increased utilizing various language educating program sheets in child edu-cating organizations or private home, this study was conducted to investigate the language educating contents being taught in the sheets and to analyze some problems of the sheets. As a first step of the study I surveyed 30 parents of children aged 4 to 5 in order to select proper program sheets which are widely used for children. From the above survey total 3 home sheets are selected arbitrarily for this investigation. As a result, most sheets have made children read the contents separating the syllables or words in reading emphasizing part, instead of making them read the contents as a whole sentence or story. In writing educating field also, it was emphasized to dictate the syllables or words just after listening to or watching them, not to the recognition of overall sentence. Also in speaking area which was low in weight as educating contents, there was a problem of repeating the names of simply suggested pictures, not inducting children to express their own thinking or feeling regarding educating contents. Even in listening field, it was not desirable to train children listen to the contents for the dictating purpose only, not helping them to understand the global flow of story.

수직점프 수행시 두 발의 동시· 비동시 스텝에 따른 운동학적 특성 분석

윤희중,이연종,이경식,유실,정남주 韓國體育大學校附屬 體育科學硏究所 1997 韓國體育大學校附屬 體育科學硏究所論文集 Vol.16 No.1

The purpose of this study is to quantify the differences between synchronous and asynchronous step during vertical jump. The subjects of this study were 3 males college students. And 2 S-VHS vedio cameras were used for the data collection. The Direct Linear Transformation (DLT) method was employed to obtain 3-D position coordinates of 21 landmarks. And the following conclusions were drawn ; 1. Synchronous step was faster in approach velocity than asynchronous step. 2. Asynchronous step was smaller in knee flexion angle than synchronous step. 3. Synchronous step was faster in angular velocity at knee flexion than asynchronous step and asynchronous step was faster in angular velocity at knee extention. 4. Asynchronous step was higher in take-off height and loss height than synchronous step. 5. Synchronous step was higher in flight height top height and reach height than asynchronous step.

김의 殼胞子에 대한 γ-線 照射效果 : I. 殼胞子의 發芽生長에 미치는 γ-線의 照射效果

金重來,金鍾連 군산대학교 1983 群山水産專門大學 硏究報告 Vol.17 No.3

I. □胞子의 發芽生長에 미치는 γ -線의 照射效果 r - Irradiation effects from □Co at 250r - 3000r on conchospores of laver (P. tenera) were examined. The major investigation was to clarify the biological effects of gamma irradiation on the germination and growth of conchospores at 48hrs after liberation, which mostly were composed of one cell yet. The results obtained were summarized as follows. 1) All conchospores served as materials germinated and developed normally to young germs at any irradiations. 2) In general, the visible irradiation effects on growth were observed at every irradiation dosage, and thus the highest growth-rate was 365% in frond-area at 1.0 KR and 126% was recorded as minimum at 250 r. 3) There is a tendency for the growth-rate curve, whose peak was at 1.0KR, to reduce slowly with increasing irradiation dosage in the range of 3.0 KR. 4) Antheridums, carpogoniums and carpospores resulted from their fertilization were observed on the fronds exposed at 1.0-1.5 KR irradiation. 5) Some giant cells and callus-like tissues multiplied abnormally were found on a few fronds at 250 r and 1.0 KR.

제자리 점프헤딩의 운동학적 연구

윤희중,문동안,이연종 한국운동역학회 1997 한국운동역학회지 Vol.7 No.1

The purpose of present study was to clarify the kinematics characteristics of standing-jump-heading by means of three-dimensional analysis of cinematography. Twenty male students were participated in the experiment as subjects. They consisted of 10 soccer players as a skilled group, and 10 control students which did never participated in the soccer club as an unskilled group. Each subject was instructed to jump by two legs for the ball which suspended with ball-pendurum. The movements of standing-jump-heading were filmed with 16mm high speed cameras that set at perpendicular position. From the obtained results, the characteriatics of standing-jump-heading was summarized as follows 1) From comparison between skilled and unskilled groups, skilled subjects showed significantly higher practical displacements during the pre-impact and post-impact phase. 2) The velocities of head and shoulder part of the body were significantly higher in skilled subjects. But focused on the velocity of hip in subjects, negative velocity appeared, change of velocity was lower than unskilled. The higher impact velocities in skilled subjects were seemed that the head and shoulder rotated about center of gravity. 3) It is considered that acceleration at impact is substituted for developed force. Then, the accelerations of head, shoulder and hip in skilled subjects were 14.6, 2.8 and 1.4 time in unskilled subjects, respectively. It is concluded that to perform standing-jump-heading, skilled subjects made their upper bodies and heads rotate strongly about center of gravity.

백서 Paraquat 두여에 의한 간과 폐 조직의 산화성 손상에서 Vitamin C와 Deferoxamine의 항산화 효과에 관한 연구

정연권,서길준,정중식,정성은,최국진,윤여규 대한응급의학회 2000 대한응급의학회지 Vol.11 No.4

Background: The toxicity of paraquat has been known to be caused by oxygen free radicals which leads to the lipid peroxidation and multiple organ failure. Although vitamin C has been known to be a potent antioxidant, recently there are numerous data which have shown that a low dose of vitamin C may act as a prooxidant due to the stimulation of the Fenton reaction with metal ions, which produces hydroxyl radicals. It has been reported that a deferoxamine in paraquat intoxication could reduce the production of the hydroxyl radicals by the inhibition of the Fenton reaction through the reduction of iron ion in tissue. The aim of this study was to evaluate the effect of the high and low dose of vitamin C and deferoxamine on lipid peroxidation and plasma TNF-α in paraquat intoxication. Methods: Female Sprague -Dawley rats were divided into seven groups: control group which was not given paraquat(20 mg/kg), P group which was given paraquat only, PVH group given paraquat and high dose of vitamin C(100 mg/kg), PVL group given paraquat and low dose of vitamin C(10 mg/kg), PVHD given paraquat, high dose of vitamine C and deferoxamine(100 mg/kg), PVLD given paraquat, low dose of vitamin C and deferoxamine, and PD given paraquat and deferoxamine. Animals were killed at 6 and 24 hours after treatment. Malondialdehyde(MDA), superoxide dismutase(SOD) and glutathione(GSH) contents, catalase activity, plasma TNF-α, and histologic changes in the lung and liver tissue were measured. Results: The lung histology in the PVH and PD or PVHD groups showed the significant decreases in the alveolar edema and interstitial thickness compared to the P group. The liver histololgy in the PVH and PVHD groups demonstrated marked differences in the central venous and sinusoidal dilatation compared to that of the P group. While the MDA levels of the lung and liver in the PVH and PD groups showed the significant reduction compared to that of the P group at 6 hours after treatment, all groups showed the significant changes compared to the P group at 24 hours. There was no significant change of the SOD levels of the lung and liver at 6 hours among all groups. At 24 hours, the SOD levels of the lung in PVH, PVL, and PVHD groups showed the significant increases compared to the P group. The increase of the SOD level in groups combined with deferoxamine, however, revealed a little reduction. The SOD level of the liver in PVH group only significantly increased compared to the P group at 24 hours. There was no significant change of the GSH level of the lung and liver among all groups at 6 hours. At 24 hours, the GSH level of the lung and liver were significantly increased in both PVH and PD group and PVH group, respectively, compared to the P group. Although the catalase activity of the lung was not significantly increased, that of liver was signiflcantly increased in both PVHD and PD groups compared to the P group at 6 hours. The catalase activities of the lung and liver were significantly increased in PVH, PD, and PVHD at 24 hours. The concentrations of the plasma TNF-α were slightly decreased at 6 hours and slightly increased at 24 hours compared to that of the P group, but they were not significant. Conclusion: This study showed that although the low dose of vitamin C had no effect, the high dose of vitamin C revealed a decrease of the MDA level and an increase of SOD, GSH, and catalase activity in the lung and liver tissues, and the effect of the high dose of vitamin C increased with time. The administration of the deferoxamine with or without high dose of vitamin C, however, significantly showed the inhibition of the lipid peroxidation and antioxidant effect and low dose vitamin C decreased the effect of deferoxamine. The effects of the vitamin C and deferoxamine on plasma TNP-α were not clearly shown.

나사산이 있는 관이음의 효과적인 해석모델의 개발

임중연,이호용,고광일 東國大學校 1996 東國論叢 Vol.35 No.-

This paper is concerned with and efficient model for the structural analysis of threaded connections which is used to assemble the tubular connections such as pipes. Advanced mechanics has been used to develop the model which yields acceptably accurate solutions for stresses when compared to other methods such as experimental or finite element analysis procedures. Beam-on-elastic-foundation equations are used to compute stresses due to assembly of the connection while bolt-nut equation and Lame' equation are used for axial loads and pressures. Numerical results show that our model is computationally efficient and valid in terms of stress distribution for make-up. The current model can provide the quick and inexpensive analysis tools to the production engineer with reasonable accuracy.

단순상한 및 확장된 일반상한제약을 갖는 선형배낭문제의 O(n^2log n) 해법

원중연 한국경영과학회 1997 한국경영과학회지 Vol.22 No.3

We present an extension of the well-known generalized upper bound(GUB) constraint and consider a linear knapsack problem with both the extended GUB constraints and the simple upper bound(SUB) constraints. An efficient algorithm of order O(n^2log n0 is developed by exploiting structural properties and applying binary search to ordered solution sets, where n is the total number variables. A numerical example is presented.

상자형 제약을 갖는 이차원 선형배낭문제의 해법연구

원중연 경기대학교 1999 論文集 Vol.43 No.2

We present a two-dimensional linear knapsack problem with the box constraint. The presented Problem is an extension of the cardinality constrained linear knapsack problem[4.5] and the two-dimensional linear knapsack problem with the GUB constraint.[2] We identify some new properties of the presented problem and derive a solution algorithm based on the parametric analysis for the knapsack right-hand-side. A numerical example is given.

수동변속기 트랜스미션케이스의 피로파괴 분석

임중연 동국대학교 산업기술연구원 1996 산업기술논문집 Vol.7 No.-

본 논문은 로드-로드 스펙트럼 분석기법을 적용하여 자동차 트랜스미션케이스의 피로파괴분석을 다룬 것이다. 수동변속기의 트랜스미션케이스는 다양한 주기적 하중을 받고 있으며 결과적으로 케이스표면에 가끔 균열이 발생되기도 한다. 본 연구에서는 지지방식이 엔지 3점지지 방식에서 트랜스미션 3점지지 방식으로 바뀌면서 발생하는 균열의 원인분석에 관한 것이다. 트랜스미션 3점지지 방식은 내구시험중 드레인플러그 부위에서 균열이 조기발생되었다. 이러한 원인을 정량적으로 분석하기 위하여 1 사이클 내구시험동안 각각의 지지방식에 대하여 누적손상량을 계산할 수 있는 실험 및 컴퓨터를 이용한 분석이 병행되었다. 결과적으로 트랜스미션 3점지지 방식이 엔진 3점지지 방식보다 트랜스미션케이스의 드레인플러그부위에 더 많은 손상을 준다는 것이 판명되었다. This paper is concerned with the fatigue fracture analysis of the automobile transmission case by applying road-load spectrum analysis technique. The manual transmission case receives various cyclic load and sometimes results in crack on the surface of case. Our study investigates the crack occurrence of new model which employes the three-point mounting support on transmission while previous one used three-point mounting support on engine. The crack has been detected near the drain plug for the type of three-point mounting support on transmission during the early stages of endurance test. To find out the cause quantitively, experiment and computational analysis have been carried out to calculate the cumulative damage for both support types during one cycle endurance test. The numerical results show that the type of three-point mounting support on transmission gives larger damages on the surface of transmission case than that of three-point mounting support on engine.