성형조건에 따른 무연탄계 활성탄의 세공특성

이송우,나영수,김도한,류동춘,최동훈,류병순,송승구 한국화학공학회 2002 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.40 No.1

본 연구는 무연탄으로 활성탄을 제조할 경우 성형이 세공특성에 미치는 효과를 고찰한 것이다. 3가지 다른 방법으로 활성탄(파쇄형 활성탄, 압축성형 활성탄, 압축성형 활성탄)을 제조하여 특성을 비교했다. 이중에서 25%의 콜타르와 7%의 물을 혼합하여 압출 성형한 활성탄이 비표면적, 세공부피, 그리고 경도에서 가장 좋은 물성을 나타내었다. 압축 및 압출 성형체의 표면은 무연탄 원탄과는 달리 무연탄 분말이 바인더와 혼합되어 있으므로 매우 거친 상태를 나타내었고, 활성화시 거칠게 형성되어 있는 입자사이로 활성화제인 수증기가 쉽게 침투하여 많은 세공을 형성시킴을 알 수 있었다. 이렇게 형성된 세공을 통해 수증기 활성화반응이 잘 일어나 직경 3,000-50,000Å 범위의 거대세공이 발달하였다. 파쇄형 활성탄에 비해 약 2배의 거대세공(macropore)부피를 가지고 있었으며 경도도 30%에서 95% 이상으로 상승되었다. This study was to investigate the effect of granulation process on pore characteristics in manufacturing anthracitebased activated carbons. The activated carbons were made by three different methods to compare characteristics: the crushed activated carbon, the compressed activated carbon, and the extruded activated carbon. Among these activated carbons, the extruded activated carbon using a binder that consists of 25% coal tar and 7% water showed the best characteristics in specific surface area, pore volume, and hardness. Since the compressed and the extruded substances had coarser surfaces than a raw material, steam could penetrate easily through particles and produce macropores especially in the diameter ranges of 3,000-50,000Å during activation process. The extruded activated carbon showed about twice more macropore volumes than the crushed activated carbon and the hardness was increased from 30% up to 95%.

섬유상 담체 종류에 따른 생물학적 오수처리 비교연구

이수구,임병란,한종옥 서울産業大學校 1994 논문집 Vol.40 No.1

This study was performed to investigate the treatability of sewage from department store by attached growth biological treatment method using several fibrous media such as Supermodule made of polyvinylidine chloride and acry fiber(FBC), ringlace made of polyvinylidine chloride(HBC) and polypropylene(PP). The pilot plant was set up in the field of K department store and four consecutive aerated reactors were packed with each media and maintained in the condition of hydraulic retention time 12 hours. Experimental results showed that the effluent BOD concentration was stable even though the influent concentration was largely fluctuated in the range of 300~900㎎/L. BOD removal efficiencies in HBC, PP and FBC systems were 90%, 87% and 94%, respectively. The influent BOD was mainly removed in the first, second and third reactors and the removal rate in the fourth reactor was the lowest due to the low concentration and low influent load. The concentration of biomass attached to fibrous media was the highest in the FBC system compared with HBC and PP systems. Total concentration of volatile solids in the FBC system was 5,900 ㎎/L which was high compared with the other media systems. The production ratios of waste sludge were 9.2, 8.45 and 7.3 gDS/㎥ of influent sewage in HBC, PP and FBC systems, respectively.

집중하중을 받는 변단면 보의 정적거동해석

이병구,모정만 圓光大學校大學院 1992 論文集 Vol.10 No.-

An analytical method was developed to tapered beams subjected to concentrated loads. The rectangular cross-section with constant width and variable depth, so-called depth taper, was chosen. The differential equation of deflected beams based on the small deflection theory was derived and solved by indefinite integration. The unknown parameters and integral constants were calculated by the boundary conditions. The hinged-hinged. hinged-clamped, clamped-clamped and clamped-hinged beams were considered in the numerical examples. As the results of this study, the reaction moments of left ends, the vertical reactions of left ends, the maximum deflections and the maximum stresses versus nondimensional position of concentrated load were presented in figures. Also both typical bending moment diagrams and deflection curves were presented in figures. It is expected that the results of this study including both all equations and figures can be used in design of the tapered beams.

우리나라 數學敎育過程의 變遷과 새 數學 運動(New Math.Movement)의 관계에 대해서

李炳守,具魯美 慶星大學校 1992 論文集 Vol.13 No.2

Views on the mathematical education are dependent on the views of the nature of mathematics. Accordingly the views of the nature of mathematics influences on the organization of the school curricula of mathematical education. In this paper we researched how the curricula of mathematical education in our country changed in connection with the new-math. movement and Back-to-basics movement about 1950 to about 1990.

도심 지역 전파 전달 특성 해석

구연건,이병훈 弘益大學校 科學技術硏究所 1997 科學技術硏究論文集 Vol.8 No.-

Characteristics of microwave reflections and diffractions in an urban crossroad is presented in this thesis utilizing geometrical optics(GO), Uniform geometrical theory of diffraction(UTD) and ray tracing technique. At first, three-dimensional multiple paths between a transmitter and a receiver at various line-of-sight(LOS) or out-of-sight(OOS) positions in the crossroad were traced using the image method. The multiple paths include direct incidence, specular wall and ground reflections and corner diffractions. Then, signal path losses to the receiver at various positions in the crossroad were computed using GO, UTD and total path lengths and reflection angles. The appropriate number of reflection for numerical convergence was computed and the effects of polarization, frequency and dielectric constant of the wall and ground on the pathloss to LOS and OOS positions are also studied. The accuracy of this method is verified by the experimental measurement in a constructed cross road. It was also applied in more complicated road structures.

被陰이 韓國잔디의 生長에 미치는 영향에 관하여

李一球,金仁澤,裵秉鎬 건국대학교 1977 學術誌 Vol.21 No.2

For the evaluation of shade tolerance of the garden plant, the growth of Zoysia, japonica Steudel was anlyzed by varing the light intensities. Light level semployed in Exp. 1 were 5, 10, 15, 20, 25, 30, and 100% daylight; and those in Exp.]2 were 7, 15, 30, 60, 70, and 100% daylight. The varing light intensities were obtaind in both case with reed screens and nylon nylon screens supported on wooden frames (1.2m 1.2m 0.6m). 1. The growth of total plant dry weight showed high value in proportion to the increase of light intensity and was depressed markedly by deeper shading. 1) The growth in total plant dry weight : The depressive effect of shading (5 and 10% plots) on the growth of total weight was conspicuously marked. Afterwards, the total plant decreased in weight and finally failed to survive after 150 days of shading. 2) The growth in root dry weight (less than 25% plot) decreased gradually until it reach almost zero after 115 days of shading. 3) The growth in leaf dry weight (less than 20% plot) decreased gradually until it reached almost zero after 115 days of shading. But the later growth condition of the leaves in the 23 and 30% plots was roughly similar to the earlier period of growth. 2. In heavy shade (5, 10, 15, 20, 25, and 30%), the depression of grwoth by sahding was conspicuoulsy marked, while the growth of the lightly shaded plants (60 and 70%) showed the same effect as the growth in full light. 3. At first the relative value of each plant organ was extraordinarily similar between 25, 30% plots and 100% daylight. However the value markedly decreased at later periods. The relative value of 60 and 70% plots was roughly the same as in the 100% plot (control plot).

菊花의 忌地性과 이에 미치는 生長物質의 影響에 관한 硏究

李一球,張秉旭 건국대학교 1968 學術誌 Vol.9 No.1

The chrysanthemum, as a perannual plant, are propergated and transplanted by root division through years. This is because of causes that chrysanthemum are inhibited in growth and development at same places, In this work we researched the soil sick and effect of growth regulators in chry-santhemum plant, supposed that such bad growth of CHRY will have a same causes in the water washing of root through CHRY in Artificial methods. The results getted through this work are as following. (1) The water washing of root inhibited clearly the growth and become a cause of soil sick in chrysanthemum. (2) The much and less of inhibitors in chrysanthemum were influenced by the environment factors (day-length), especially the inhibitor resulted in short-day treatment inhibited the growth in Chrysanthemum (3) The growth regulators increased the resistances to soil sick, and its incorporation into CHRY controlled and inhibited the action of inhibitors (TAA of these is most effective). A sample variety of the same white small line of Chrysanthemum moliforium was used for the effects of W.W.R. on the growth and rooting of treated plant were observed, and effects of G.R in relation to sick soil of Chrysanthemum was measured to inhibit and remove the unfavorable actions of W.W.R on their growth and development. In all cases the W.W.R. of chrysanthemum inhibited the growth and rooting of their self-plant and the W.W.R. resulted under short-day inhibited all growth and rooting of than the other day-length. The G.R. increased the resistances to the soil sick in chrysanthemum and their incorporation into the leaves could moderate and inhibit the effectiveness of W.W.R.

한국산 가시톡토기과의 분류학적 검토

이병훈,이원구,김학렬 全北大學校 生物學硏究所 1984 生物學硏究年報 Vol.5 No.-

A preliminary test concerning variabilities of some Tomoceridae species of collembola has been made using scanning electron microscopy and enzyme analysis. No definite taxono mical characters were detected in the integument of 6 species belonging 2 subgenera of Tomocerus genus. The zymograms obtained by electrophoresis, however, revealed that th subgeneric characters at times should be questioned for its monophyletic meaning as suggested by those of Tomocerus (Tomocerus) kinoshitai showing a particular pattern and Tomocerus (Tomocerina) liliputanus for its apprectable variability. The distinctive zymograms of T.laxalamella might also justify the creation of a new subgenus when considered in combination with the morphological characteristics of mucron. Neither population nor interspecific difference were observed, however, in and between T. cuspidatus and T. ocreatus, which would remain problematic and necessitate further works to confirm. Tomocerus laxalamella and T. liliputanus showed more of less variabilites whereas Homidia koreana of Entomobryidae, used as out-group for comparison, displayed a prominent individual variations in a few loci.

복합재를 이용한 구조물의 균열보수 대책에 관한 연구

李晟熙,韓秀贊,韓秉基,具秉俊 弘益大學校 科學技術硏究所 1997 科學技術硏究論文集 Vol.8 No.-

Recently, composite materials have widely become available to engineers. This paper briefly explains the applications of these materials and shows how these materials can be used to repair structures with damages such as crack, notch, etc. Before the fatigue test, notched and repaired specimens with thin laminate composite are prepared. Also, test apparatus is designed to perform four point fatigue test of specimens. From the experimental result, it was found that present repair technique could be used to enhance the life of damaged structures.

생물학적 소양의 함양을 위한 BSCS 통합 권고안과 6, 7차 교육과정 비교

구수정,김영신,김병석,이성조,정완호 한국교원대학교 과학교육연구소 2000 청람과학교육연구논총 Vol.10 No.1

본 연구에서는 BSCS 위원회가 생물학적 소양의 함양을 위하여 제시한 중등 생물 교육과정 개발 지침과 우리 나라 제6차, 제7차 교육과정을 개념 제시 형태, 하위 개념들의 내용 일치도, 개념 수의 측면에서 비교 분석하였다. 연구 결과 우리 나라 교육과정의 내용 체계에서의 상의 수준으로서의 지식 영역과 하위수준으로서의 내용 요소 부분에 제시되어 있는 개념들이 포괄성의 차이 없이 단순히 개념 나열적으로 제시되어 있는 상태라서 개념 수준간 등급화가 충분하지 못한 것으로 나타났다. 그리고 우리 나라 생물 교육과정에는 생태계, 유전과 생식, 물질대사 부분에 너무 많은 개념들이 들어 있는 것으로 나타났는데 이로부터 BSCS가 학문중심 교육 과정기에 제시했던 많은 개념들에 대해서 현 시대 흐름에 비추어 학생들의 생물학적 소양의 함양을 위해 재조정하도록 권고하면서 제시한 6개의 통합 원리들을 편중되지 않게 고르게 포하하기 위해서는 우리 나라에서도 생물교육과정에 대한 재구성 노력이 필요한 것을 알 수 있었다. 한편 생물 Ⅰ보다 생물 Ⅱ에 생물학적 소양의 함양을 위한 필수 개념들이 더 많이 제시되어 있는 것으로 분석되었는데 이는 우리 나라 제7차 교육과정의 과학 10에서 과학적 소양이, 그리고 생물 Ⅰ에서 생물학에 대한 기초 소양이 강조되고 있고, 생물 Ⅱ에서는 생물학 관련 전공 과목 이수 준비를 강조하고 있는 과목별 성격과 목표에 부합되지 않는 것이며 따라서 우리나라 교육과정에서도 각 과목별 특성을 분명히 제시 및 반영하려는 노력이 필요함을 알 수 있었다. 이상과 같은 연구 결과로부터 현재 우리 나라 과학 및 생물 교육의 중요한 목적의 하나로 설정되어 있는 학생들의 생물학적 소양의 함양을 위해서 제7차 교육과정에 의한 생물 교과서의 교수 자료 개발 및 장차 제8차 교육과정 개발에 사용할 수 있는 실제적인 지침을 마련하기 위한 구체적인 논의가 있어야 함을 시사받았다. In this study, the concept presentation form, the content coherence of sub-dimensional concepts and the number of concepts of the 6th and the 7th Korean curriculum were analyzed comparing the guide to developing the secondary biology curricula to develop biological literacy with BSCS. According to the result, the discrimination between concept levels in the frame of contents of the Korean curricula is insufficient, because each of concepts presented in the knowledge domain as upper level and sub-dimensional concept elements as lower level are simply arrayed. Considering too much concepts of ecosystem, genetics, reproduction and metabolism, there should be an effort to reform the biological curriculum to include concepts evenly, not in the biased state, to reflect all the 6 unifying principles by BSCS for developing students' biological literacy. Finally there should be an effort to reflect the characteristics of each subjects concretely among Science 10, Biology Ⅰ and Biology Ⅱ in the 7th curriculum considering the result that essential concepts to develop biological literacy are presented more in some principles of Biology Ⅱ than Biology Ⅰ. Thinking the results of the present study, concrete discussions should be made to set up the standard reference about biological literacy and to present essential concepts for teaching and learning to develop it in the process of biology textbook development for meeting the 7th Korean curriculum and in the development of 8th Korean curriculum in advance.