• Title/Summary/Keyword: type 347

Search Result 261, Processing Time 0.023 seconds

Fiber optic smart monitoring of concrete beam retrofitted by composite patches

  • Kim, Ki-Soo;Chung, Chul;Lee, Ho-Joon;Kang, Young-Goo;Kim, Hong
    • Structural Engineering and Mechanics
    • /
    • v.17 no.3_4
    • /
    • pp.347-356
    • /
    • 2004
  • In order to extend the lifetime of buildings and civil infrastructure, patch type fibrous composite retrofitting materials are widely used. Retrofitted concrete columns and beams gain stiffness and strength, but lose toughness and show brittle failure. Usually, the cracks in concrete structures are visible to the naked eye and the status of the structure in the life cycle is estimated through visual inspections. After retrofitting of the structure, crack visibility is blocked by retrofitted composite materials. Therefore, structural monitoring after retrofitting is indispensable and self diagnosis method with optical fiber sensors is very useful. In this paper, we try to detect the peel out effect and find the strain difference between the main structure and retrofitting patch material when they separate from each other. In the experiment, two fiber optic Bragg grating sensors are applied to the main concrete structure and the patching material separately at the same position. The sensors show coincident behaviors at the initial loading, but different behaviors after a certain load. The test results show the possibility of optical fiber sensor monitoring of beam structures retrofitted by the composite patches.

Positioning and vibration suppression for multiple degrees of freedom flexible structure by genetic algorithm and input shaping

  • Lin, J.;Chiang, C.B.
    • Smart Structures and Systems
    • /
    • v.14 no.3
    • /
    • pp.347-365
    • /
    • 2014
  • The main objective of this paper is to develop an innovative methodology for the vibration suppression control of the multiple degrees-of-freedom (MDOF) flexible structure. The proposed structure represented in this research as a clamped-free-free-free truss type plate is rotated by motors. The controller has two loops for tracking and vibration suppression. In addition to stabilizing the actual system, the proposed feedback control is based on a genetic algorithm (GA) to seek the primary optimal control gain for tracking and stabilization purposes. Moreover, input shaping is introduced for the control scheme that limits motion-induced elastic vibration by shaping the reference command. Experimental results are presented, demonstrating that, in the control loop, roll and yaw angles track control and elastic mode stabilization. It was also demonstrated that combining the input shaper with the proportional-integral-derivative (PID) feedback method has been shown to yield improved performance in controlling the flexible structure system. The broad range of problems discussed in this research is valuable in civil, mechanical, and aerospace engineering for flexible structures with MDOM motion.

A study on the KLA behaviors in HAZ and the mechanical properties of austenitic stainless steel weld (스테인레스강용접 열영향부의 KLA거동 및 기계적 특성에 관한 연구)

  • 조종춘;김영석;김학민
    • Journal of Welding and Joining
    • /
    • v.8 no.4
    • /
    • pp.27-34
    • /
    • 1990
  • Integranular corrosion behaviors of KAL (Knife Line Attack) and mechanical properties such as tensile and creep rupture were investigated for the tube material used for nearly 20 years under the condition of 463.deg. C and 28 $kg/cm^2$. Based and weld metal were austenitic stainless steel AISI 321 containing Ti, AISI 347 containing Nb, respectively. KLA is a kind of the intergranular corrosion which often occurs just near the HAZ (heat affected zone) of AISI 321 and AISI 347 stainless steel due to the grain boundary sensitization. In KLA zone, intergranular corrosion crack has propagated outwards from the inner surface and carbides of white and narrow band type assuming as (Cr, Fe) carbide were confirmed. All the delta-ferrite formed in the weld metal during weld solidification has been transformed into sigma-phase since delta-ferrte was exposed for 20 years at 463.deg. C. Elongation was very low at the range from room temperature to 600.deg. C and it was confirmed that creep-rupture properties were not consideralbly affected.

  • PDF

The Design Characteristics of Modern Children's Clothes - Focus on Children's Clothes for Girls From The 2006S/S-2010S/S Collections - (현대 아동복의 디자인 특성 분석 - 2006S/S~2010S/S 컬렉션의 여자 아동복를 중심으로 -)

  • Kong, Mi-Ran
    • Fashion & Textile Research Journal
    • /
    • v.14 no.3
    • /
    • pp.347-362
    • /
    • 2012
  • The analysis results of the characteristics of children's clothes for school girls from the 2006S/S-2010S/S collections reveal that the most frequent type of item composition was 2'PS & 3'PS. T-shirts were the popular kind of item for upper garments and pants for lower garments. The major silhouettes were H and A line. The predominant neckline was U, which was followed by camisole and V. The major collar styles were stand-up and flat. Chromatic colors were used more than achromatic ones and after white the most popular colors were blue, pink, red, black, navy, and green. The dominant color scheme was a two-color or three-color scheme. The percentage of solid and patterned material garments was the highest and the most popular pattern was flowers. The most popular style of garment had no decorative detail that was followed by one-item, two-item, and three-item decoration. The major kinds of decorative detail were frills, pleats, and prints.

Estimation of Compressive Strength of Concrete Using Blast Furnace Slag Subjected to High Temperature Environment (고온환경 조건하에서 고로슬래그를 사용한 콘크리트의 압축강도 증진 해석)

  • Han, Min-Cheol;Shin, Byung-Cheol
    • Journal of Environmental Science International
    • /
    • v.16 no.3
    • /
    • pp.347-355
    • /
    • 2007
  • In this paper, estimation of the compressive strength of the concrete incorporating blast furnace slag subjected to high temperature was discussed. Ordinary Portland cement and blast furnace slag cement (BSC;30% of blast furnace slag) were used, respectively. Water to binder ratio ranging from 30% to 60% and curing temperature ranging from $20^{\circ}C{\sim}65^{\circ}C$ were also chosen for the experimental parameters, respectively. At the high temperature, BSC had higher strength development at early age than OPC concrete and it kept its high strength development at later age due to accelerated latent hydration reaction subjected to high temperature. For the strength estimation, the Logistic model based on maturity equation and the Carino model based on equivalent age were applied to verify the availability of estimation model. It was found that fair agreements between calculated values and measured values were obtained evaluating compressive strength with logistic curve. The application of logistic model at high temperature had remarkable deviations in the same maturity. Whereas, the application of Carino model showed good agreements between calculated values and measured ones regardless of type of cement and W/B. However, some correction factors should be considered to enhance the accuracy of strength estimation of concrete.

Development of a New Flue - cured Tobacco Variety KFl13 by Nicotiana africana Method (Nicotiana africana 방법에 의한 황색종 연초 신품종 KF113 육성)

  • 정윤화;금완수;조명조;백기현;신승구;조수헌;진정의;이승철
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.16 no.1
    • /
    • pp.69-75
    • /
    • 1994
  • A new flue - cured tobacco variety KF113 was developed by Nicotiana africana method from a cross of NC82 and Coker 347 at the Suwon Experiment Station. It was tested in the 0fficial Variety Test in 1991-1992 and the flue - cured Regional Farm Test in 1992. KFl13 flowers 4 days later than WC82 (standard variety in Korea) and its harvestable leaves are 2 more than those of NC82. The leaf type and shape of KFl13 resembles Coker 347. It has high resistance to bacterial wilt (Pseudomonas solanacearum) and black shank (Phytophthora parasitica var. nicotianae), and is susceptible to tobacco mosaic virus. It should adapt well to the flue - cured production area and can reduce premature flowering under unfavorable weather conditions. Yield of KFl13 is 5% higher than that of NC82, and nearly equal in value per kg compare with NC82. This variety met acceptable standards for chemical and physical characteristics of cured leaf and for smoking taste evaluated by panel members in Korea Ginseng & Tobacco Research Institute.

  • PDF

Arabidopsis SIZ1 positively regulates alternative respiratory bypass pathways

  • Park, Bong-Soo;Kim, Sung-Il;Song, Jong-Tae;Seo, Hak-Soo
    • BMB Reports
    • /
    • v.45 no.6
    • /
    • pp.342-347
    • /
    • 2012
  • Plant mitochondria possess alternative respiratory pathways mediated by the type II NAD(P)H dehydrogenases and alternative oxidases. Here, E3 SUMO ligase was shown to regulate alternative respiratory pathways and to participate in the maintenance of carbon and nitrogen balance in Arabidopsis. The transcript abundance of the type II NAD(P)H dehydrogenases NDA2 and NDB2 and alternative oxidases AOX1a and AOX1d genes was low in siz1-2 mutants compared to that in wild-type. The addition of nitrate or ammonium resulted in a decrease or an increase in the expression of the same gene families, respectively, in both wild-type and siz1-2 mutants. The amount of free sugar (glucose, fructose and sucrose) was lower in siz1-2 mutants than that in wild-type. These results indicate that low nitrate reductase activity due to the AtSIZ1 mutation is correlated with an overall decrease in alternative respiration and with a low carbohydrate content to maintain the carbon to nitrogen ratio in siz1-2 mutants.

Prosthetic rehabilitation for a glossectomy patient - a clinical report (혀절제술을 시행한 환자의 보철적 수복 증례)

  • Yoon, Jiyoung;Lee, Siho;Lee, Jiyoen;Oh, Namsik
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.51 no.4
    • /
    • pp.347-352
    • /
    • 2013
  • Malignant tumours of the oral cavity that require resection of the tongue result in severe deficiencies in speech and deglutition. In such patients, improvements in mastication, swallowing, and speech may be reasonable goals for treatment. The viability of a prosthodontic approach to treatment depends on the type and extent of surgery. In a total glossectomy, a mandibular tongue prosthesis is the treatment of choice. Mandibular tongue prosthesis occupies the space in the floor of the oral cavity. It provides the patients with a platform for directing food into the esophagus and aids in speaking. This type of prosthesis can achieve that protection of the underlying fragile tissue and improvement in appearance and psychosocial adjustment. This case report describes the technical steps involved in prosthetic rehabilitation for a glossectomy patient.

Field Application of High Strength Concrete by Cement Types Using Maturity (적산온도를 이용한 시멘트 종류별 고강도 콘크리트의 현장 적용성)

  • Kim, Dong Baek
    • Journal of the Society of Disaster Information
    • /
    • v.16 no.3
    • /
    • pp.472-478
    • /
    • 2020
  • Purpose: The purpose of the study is to help economic and safe construction by accurately predicting the initial strength of high-strength concrete (70MPa) for each type of cement, securing reliability of concrete quality, and drawing accurately the timing of form deformed, tensioning time of PS concrete, and openning of traffic after road repair with maturity. Method: Calculate the maturity by measuring the hydration heat with cement type for each age, and measure the strength of concrete with age to predict the strength corresponding to the any maturity. Result: In estimating the time required for traffic opening in road repair, ASTM C1074 was theoretically estimated at 16.4 hours for high-strength concrete, but in this study, maturity was calculated at 307, 14.4 hours for OPC and maturity at 2700, 34 hours for LHPC and maturity 200, 8 hours for ESPC. Conclusion: The timing of form deformed of structures using high-strength concrete and the opening of traffic of road repair may be much faster than in the case of concrete using OPC below the design basis strength 40MPa applied by ACI Committee 347.

OPTICAL PROPERTIES Of SEA WATER IN THE NORTHWEST PACIFIC (북서태평양에서의 해수의 광학적 성질)

  • YANG Yong Rhim
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.10 no.4
    • /
    • pp.237-241
    • /
    • 1977
  • Optical properties were studied in the Northwest Pacific near Kamchatka Peninsula based on ten oceanographic stations from September 20 to 24, 1976. Submarine light intensity was measured by usins a submarine illuminometer (RIGO, Type: 2501-A) ; equipped with a red filter (RIGO, Type: V-R-60, wave length: 600-620 nm). Light intensity in the upper 40 m depth layer was measured at 1 m depth intervals. The absorption coefficient for red color in the area ranged from 0. 178 to 0.376 (mean 0.278) : the Secchidisc depth in the area ranged from 9 to 12 meters (mean 10.6 meters). The relationship between absorption coefficient (m) and transparency depth (D) was m=5.347/D. The rates of light penetration for red color at three different depths are computed with reference to the surface light intensity. The mean rates of light penetration were $16.36\%\;(6.45\~23.5\%),\;3.65\%\;(1.38\~7.31\%)\;and\;0.276\%(0.048\~0.647\%) $ at the depths of s m, 10 m, and 20 m, respectively.

  • PDF