• Title/Summary/Keyword: Chracteristics

Search Result 209, Processing Time 0.024 seconds

Model Study of Aesthetic Database System of Architectural Precedents for Design Reference (설계참조를 위한 건축선례의 미학적 정보체계 모형연구)

  • Kim, Kyong-Soo
    • Journal of architectural history
    • /
    • v.5 no.2 s.10
    • /
    • pp.83-95
    • /
    • 1996
  • Computerized visual database construction of architectural precedents has just begun in some research institutes in the world. In Korea the first visual database has shown its testl version by S architectural design firm in september 1996. In this article the author discusses the historical contexts and the recent computerization cases, the traits, the uses and the limits of architectural visual database system of precedents. The forms and contents of data fields in two cases are compared with a focus on the description of architectural traits of each data entry. Compared to the KIA format, the S database has better performance for architectural design reference because it collects more pictures and drawings and larger texts for the field of architectural chracteristics. But this latter also is constrained by its capacity of memory and so lacks the reciprocity of the DOORS in the Graduate School of Design, Harvard University. A visual database system which has more flexible allocation of memory and respondent with the users is yet to be prepared. But this system also should be maintained by some experts in architectural history, theory and criticism, because their knowledge is essential for selection of precedents and revision of the data description. A full-fledged electronic visual database in architecture will not only save much effort for the architect, but also will change the architects' design behavior. Nevertheless this does not mean the automatic promotion of architects' creativity.

  • PDF

COMPOSITIONAL DEPENDENCE OF $128^{\circ}$ Y CUT $LiNbO_3$ CRYSTALS ON SAW CHRACTERISTICS ($128^{\circ}$ Y Cut $LiNbO_3$단결정의 조성비 변화에 따른 SAW특성변화)

  • 이상학;한재용;조순형;윤의박
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.2 no.1
    • /
    • pp.30-36
    • /
    • 1992
  • In order to measure the characteristics of Surface Acousitc Wave(SA W) with compositions of $LiNbO_3$ single crystal, $128^{\circ}$ Y cut wafer was fabricated from $LiNbO_3$ single crystals with the composition range of 47-50 $Li_2O$mol%. Delay lines were formed on the $128^{\circ}$ Y cut wafer using photolithography technique. Delay time was measured by pulse-echo overlap method. The compositional dependence of SAW characteristics, SAW velocity, electro-mechanical coupling coefficient$(K_s^2)$ and temperature coefficient of delay time(TCD), were investigated.

  • PDF

A Study on Thermal Characteristic Carbon and other Elements in Suspended Particulates (대기 입자상물질중 탄소(C)등의 열적특성에 관한 조사연구)

  • 황경철
    • Journal of Environmental Health Sciences
    • /
    • v.16 no.2
    • /
    • pp.31-39
    • /
    • 1990
  • An analytical method for particulate carbon and other elements by using elemental analyzer was investigated. Carbon, hydrogen, and nitrogen was determined as CO$_{2}$, H$_{2}$, and N$_{2}$, respectively. Organic was determined after scparation from elemental carbon(Cae) by volatilization and thermal decomposition in a heated helium flow. With organic materials examined in this reprot, more than 90% of carbon was detected as above 600$^{\circ}$C. But it is considered that a few percents of some compounds were charred above 550$^{\circ}$C. A small amount of Cae was oxidized in the inert atmosphere above 850$^{\circ}$C, but the reason was not explained clearly. Based on the thermal chracteristics of Cao it was found that the optimum temperature of heating in the helium flow of an elemental analyzer for Cao analysis is 630$^{\circ}$C. Carbon in a sample after removing Cao was assumed as Cae and the gramatom ratio of hydrogen to carbon in the sample was 0.4 and less. Rescovery of nitrogen derived from some ammonium salts and nitrates was 100% by two-step measurement with elemental analyzer. By the analytical method investigated in this report, carbon and other elements in suspended particulates(S.P) collected at an urban area in Seoul were measured. There was a good correlation between total nitrogen in SP measured by elemental analyzer and nitrogen estimated form ammonium ions and nitrate ions in SP. The nitrogen from these ions accounts for 80% of the total nitrogen. It is further suggested that the residue(20%) of the total nitrogen is attributed to the other nitrogeneous compounds.

  • PDF

Combustion Chracteristics of Veneers Treated by Ammonium Salts (암모늄염 처리 베니어의 연소특성)

  • Chung, Yeong-Jin
    • Applied Chemistry for Engineering
    • /
    • v.18 no.2
    • /
    • pp.194-198
    • /
    • 2007
  • Veneer plate was painted by the treatment with ammonium salts such as ammonium chloride (AMCR), ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP) at room temperature. The physical property and flammability of painted veneer plate were investigated. In order to evaluate flammability of the treated veneer with ammonium salts, heat release rate (HRR) of the veneer was measured by a cone calorimeter according to ISO 5660-1 standard. The flammability painted veneener plate with ammonium salts was reduced compared to virgin veneer plate. The flashover possibility of veneer plates treated with these ammonium salts was examined by R. V. Petrella's classification using time to ignition and peak heat release rate. The specific gravities of veneer plates treated with only ammonium sulfate were higher than that of virgin veneer plate. Also, the veneer plates treated with ammonium salts showed lower equilibrium moisture contents over virgin veneer.

Present and Future Prospect in Zoysia Grass Breeding (한국잔디류(Zoysia Grass)의 육종현황)

  • 주영규;김두환;이재필;모숙연
    • Asian Journal of Turfgrass Science
    • /
    • v.11 no.1
    • /
    • pp.73-85
    • /
    • 1997
  • Although zoysia grass (Zoysia spp.) has a lot of excellent chracteristics as warm-season grass, it have been limited in use due to slow establishment, low seed production, poor shade tolerance and other factors. Breeding trials have been continued from 1900's, much attentions have been paid especially in U.S.A., Korea and Japan recently. In U.S.A., more than 24 varieties had been evaluated at National Turfgrass Evaluation Program(NTEP) from 1991 to 1995 and some were regsistered as commercial. After the 6th International Turfgrass Research Conference at Japan in 1989, Japan Turfgrass In-corporation (JTI) sponsored by private companies and government carried out breeding programs for pest, salt, and shade tolerant and herbicide resistant varieties. JTI also has been trying to im-prove vigor and breed evergreen zoysia Korean breeders collected germplasms since 1960's. After USDA breeders came to Korean penesula in 1982, Korean breeders joined with USDA zoysia breeding project for several years. Many interspecific hybrids and natural selected varieties were breeded that period both in U.S.A and Korea. Breeding objectives were to extend green color period, improve leaf quality and density, and better leaf color at dormant stage. Since 1990's, zoysia grass breeding trials are getting more diverse in many points such as random amplified polymorphic DNA (RAPD) assay for ecotype identification. The objectives of this study are to evaluate germplasms in Korea, and also review the present status and future prospect in zoysia grass breeding in the world.

  • PDF

Fabrication and Chracteristics of Magnetic Sensor using Ceramic Superconductor (산화물 초전도체를 이용한 자기센서의 제작 및 특성)

  • Lee, Sang-Heon
    • Journal of IKEEE
    • /
    • v.3 no.2 s.5
    • /
    • pp.243-249
    • /
    • 1999
  • A magnetic field sensor is fabricated with superconducting ceramics of Y-Ba-Cu-O system. The prepared material shows the superconductivity at about 95K. The sensor at liquid nitrogen temperature shows the increase in electrical resistance by applying magnetic field. Actually, the voltage drop across the sensor is changed from zero to a value. more than $100{\mu}V$ by the applied magnetic field. The change in electrical resistance depends on magnetic field. The sensitivity of this sensor is 2.9 ohm/T. The sensing limit is about $1.5{\times}10^{-5}T(=1.5{\times}10^{-1}G)$. The increase in electrical resistance by the magnetic field is ascribed to a modification of the Josephson junctions due to the penetrating magnetic flux into the superconducting material.

  • PDF

Behavior of Steel Beam Connections under Cyclic Loading (반복하중을 받는 철골보 접합부의 거동)

  • 이승준;김상배
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.3 no.4
    • /
    • pp.23-32
    • /
    • 1999
  • Behavior of H-beam connections under cyclic loadings is investigated experimentally in this study. The purpose of this study is to study the effect of steel properties and coping shape on the hysteretic behavior of H-beam connections. Five beam-to-column connection specimens were fabricated and tested under cyclic loadings. The load-rotation curves of the beam connections were mainly obtained. Deformation capacity and energy dissipation capacity of the connections are compared each other. The connections fabricated from SS400 showed good deformability and energy dissipation capacity, but those from SM490 showed brittle fracture at the connection. The coping shape at the connections showed a little difference in cyclic behavior.

  • PDF

A Study on the Alkaline treatment of Polyester Fabric - The effect of correlation with the physical, sensory properties and handle- (폴리에스테르 직물의 알칼리가공에 관한 연구 -물리량, 관능량과 태와의 상호관계를 중심으로-)

  • Jeong Je Seok
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.10 no.3
    • /
    • pp.9-16
    • /
    • 1986
  • In this research, we tested the fertile physical and the sensory properties and the handle of the domestic polyester fabrics were treated with the varying alkaline concentrations and temperatures were tested. The tests were conducted to determine the effects of the alkaline treatment on the changes of the physical and the sensory chrateristics of the domestic polyester fabrics. The results were as follows; 1. When treated with the varying alkaline concentrations from $7.5\%$ to $15\%$ at temperatures from $60^{\circ}C$ to $90^{\circ}C$, the weight decreasing phenomena were shown to as a linear equations increase in that range. 2. As the weight loss increased, the softness and the smoothness were increased but the fullness and the tightness were decreased. 3. The positive correlations were found between the sensory and the physical properties, and the fullness ana the tightness, while a negative correlation was found between softness and the smoothness. 4. The regression equations obtained by the sensory chrateristics related with the physical chracteristics were as follows ; Softness: y=84.01-0.74x Fullness : y=0.06+0.78x Smoothness: y=88.67-0.82x Tightness : y= 0.34+0.79x

  • PDF

The Influences of America on 20th Century Men's Fashion - From 1890's to World War II- (20세기 남성패션에 미친 미국의 영향 -1890년대부터 2차대전 까지-)

  • 이숙희
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.20 no.1
    • /
    • pp.87-97
    • /
    • 1996
  • Journal of the Korean Society of Clothing and Textiles Vol. 20, No. 1 (1996) p. 87∼9'F The purpose of this study was to identify the change and chracteristics of 20th men's fashion under the influences of America. The result of the study as follows: 1. England had led men's fashion and introduced new styles of men's fashion such as oxford bags, plus fours, drape cut etc. in the early of 20th century. But America, which had the strongest Political and financial power after World War I, II, proposed Americans cut, soot sit, bold look. 2. In the first half of 20th century men's fashion was no longer created by imitation royalty and students of private school. American movies exerted tremendous influences on the clothing styles. Genereal public adopted the dress of movie stars and American men's fashion magazines inspired the new fashion and generated sales. So America made a contribution towards democratization of men's fashion. 3. Automobile industry and leisure living of America changed American life styles and clothing styles. The wealthy made fashionable tours to foreign country and European beach resorts. So their casual styles, summer business suits and dinner jackets effected 20th men's fashion. Therefore America played an important role in casualization of men's fashion.

  • PDF

Evaluation of wear chracteristics for $Al_{2}O_{3}-40%TiO_{2}$ sprayed on casting aluminum alloy (주조용 알루미늄합금의 $Al_{2}O_{3}-40%TiO_{2}$ 용사층에 대한 마멸특성 평가)

  • 채영훈;김석삼
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
    • /
    • 1997.10a
    • /
    • pp.183-190
    • /
    • 1997
  • The wear behaviors of $Al_2O_3-40%TiO_2$ deposited on casting aluminum alloy(ASTM A356) by plasma spray against SiC ball have been investigated experimentally. Friction and wear tests are carried out at room temperature. The friction coefficient of $Al_2O_3-40%TiO_2$ coating is lower than that of pure $Al_2O_3$ coating(APS). It is found that low friction correspond to low wear and high friction to high wear in the experimental result. The thickness of $Al_2O_3-40%TiO_2$ coatings indicated the existence of the optimal coating thickness. It is found that a voids and porosities of coating surface result in the crack generated. As the tensile stresses in coating increased with the increased friction coefficient. The columnar grain of coating will be fractured to achieve the critical stress. It is found that the cohesive of splats and the porosity of surface play a role in wear characteristics. It is suggested that the mismatch of thermal expansion of substrate and coating play an important role in wear performance. Tensile and compressire under thermo-mechanical stress may be occurred by the mismatch between thermal expansion of substrate and coating. This crack propagation above interface is observed in SEM.

  • PDF