• Title/Summary/Keyword: similar materials

Search Result 4,776, Processing Time 0.089 seconds

Chronic subtalar joint instability - One case report - (거골하 관절의 만성 불안정성 - 1예 보고 -)

  • Lee, Jin-Woo;Kwon, Oh-Ryong;Park, Kwan-Kyu;Kang, Eung-Shick;Hahn, Soo-Bong
    • Journal of Korean Foot and Ankle Society
    • /
    • v.6 no.2
    • /
    • pp.251-255
    • /
    • 2002
  • Purpose: Chronic subtalar instability is not common and similar to chronic ankle instability and the incidence and cause chronic subtalar instability are not well known. Recently we have experienced chronic subtalar instability without chronic ankle instability which was treated with modified Brostrom procedures. Materials and Methods: The patient is 46 year old man who has suffered from left ankle sprain for 30 years and recently aggravated more than twice a day. On subtalar stress view, 14 degree angulation of subtalar joint was noted and on anterior drawer view, 8 mm anterior displacement of left ankle was seen. Results: In operation, there was no anterior talofibular ligament abnormility but calcaneofibular ligament loosening was found. Ligament reconstruction was performed using modified Brostrom procedure. At 12 months after operation, the patient complains no pain and no limit of motion and no instability. Conclusion: We experienced chronic subtalar instability without ankle instability treated with modified Brostrom procedures. No instability was found after treatment without complication.

  • PDF

A Study on Estimation of Consumption of Mink Clothes (밍크 모피 제품의 소모량(consumption)산출에 관한 연구)

  • Kim, Ji-Young
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.16 no.2
    • /
    • pp.177-188
    • /
    • 2014
  • A fur has emerged as one of fashion staples. there has been a rising interest in fur industry. Therefore, this study investigated how to estimate the amount of raw materials consumed at the production of fur clothes, and the scope of the study was limited to mink clothes. For an empirical study, in addition, Koreans' favorable mink design was chosen based on previous studies and sales of fur clothes, and its consumption was estimated. The consumption of mink clothes depends on the special feature of natural resources such as place of origin, gender and variety. Therefore the method of consumption for mink clothes is inevitably different from it of fiber clothes. Considering the procedure of mink clothe's production as collect same kind of a fur and process though pattern placement, first is outfut work for consumption. At estimation of the consumption of mink clothes, the number of minks was counted by matching the area of mink skin with that of the mink cloth patterns. Then, the usable area of the patterns was calculated after splitting them into diverse figures such as triangle, quadrangle and trapezoid. If we divide area by using the similar in shape of pattern and calculate, We can find high efficiency by reducing extra space. Specially we can expect more efficient work system when we use computers for efficient division of area.

  • PDF

A fundamental Study on the Performance Improvement of Hwangto plaster (황토미장재 성능개선을 위한 실험적 연구)

  • Hwang, Hey-zoo;Lee, Jong-kuk;Kang, Nam-yi
    • KIEAE Journal
    • /
    • v.5 no.3
    • /
    • pp.49-56
    • /
    • 2005
  • Recently the Volatile Organic Compound, HCHO, a harmful object spout from the construction materials is made an issue of social problem. Also the appearance of the building where the confidentiality is high was interior air pollution and it was brought about a huge problem. The government research facility and a relation industry sector conducts a many effort to improves like this actual condition. The Diverse ability building material which contains the natural material of the jade, the charcoal and the hwangto instead of the finish material which contains the harmful chemical material, is becoming development and utility. Hereupon the study have carried out research on hwangto plaster that was composed of hwangto and rice straw. The result of test that is deduced by basic proportion is properly appeared with suitable ratio of the hwangto and the sand to 4:6~5:5 by the compressive strength and crack control, workability. The result of test, that adds the rice straw to basic blending for a crack control, appeared with the fact that it is most suitable 3%to add the rice straw that has a length of 0.5cm~2cm. The result of test that plaster over the large size to compare a cement plaster with a hwangto plaster show a similar efficiency by workability. Also it controlled the crack and peeling off actual condition which is discovered from the hwangto plaster of existing perfectly.

A Study on Selection of Pipe Materials Considering EWT (EWT를 고려한 지중열교환기 파이프 선정에 관한 연구)

  • Ryu, Hyung-Kyou;Chung, Min-Ho;Lee, Byung-Seok;Choi, Hyun-Jun;Choi, Hang-Seok
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.10 no.2
    • /
    • pp.13-18
    • /
    • 2014
  • This paper proposes an optimum pipe material (PVC vs. PE) design & selection for open loop ground heat exchangers. Heat exchange efficiency and/or workability, and the need for trench insulation were investigated by comparing EWT (cooling mode) of each system. CFD simulations for the PVC and PE pipe with the same inner diameter show similar EWT. This is because the PVC pipe has a small thickness but a low thermal conductivity as compared to the PE pipe, and thus these two properties tend to offset each other. However, a hypothetically insulated pipe led to a meaningful drop of EWT. This means pipe insulation is of importance in performance of ground heat exchangers. From analyzing climate data and system operation, it is not advantageous to insulate trench pipes due to construction difficulties and ground temperature characteristics that are seasonally varied.

Manufacture and Properties of Coal Fly Ash-Clay Body (석탄회-점토계 소지의 제조 및 물성)

  • 송종택;윤성대;류동우;한경섭
    • Journal of the Korean Ceramic Society
    • /
    • v.33 no.7
    • /
    • pp.771-778
    • /
    • 1996
  • Utilization of fly ash by-produced from coal fired power plants and classified as general waste became very important problem to solve in the environmental protection and recycling of waste materials. The possibility of large scale substitution of fly ash as a raw material for bricks and wet tiles was highly expected because the chemical compositions of fly ash were mostly Al2O3 and SiO2 and the properties of it were very similar with clay. Accordingly in order to investigate the substitutional limit these specimens were substituted from 0 to 100 wt% fly ash by 20wt% increment for clay. Fly ash-clay bodies were fired at 1200, 1250 and 130$0^{\circ}C$ and then their properties were measured, It was found that these specimens sintered at 125$0^{\circ}C$ had a good bending strength. Especially when these sintered bodies were added to 20, 40 and 60 wt% fly ash the bending strength of those were 201 , 205 and 191kg.cm2 respectively with the water absorption below 1%, This showed that fly ash could be substituted ab 60 wt% in this experiment.

  • PDF

A Study on the Synthesis of Anorthite and its Characteristics. (Anorthite의 합성 및 그 특성에 관한 연구)

  • 백용혁;이종권
    • Journal of the Korean Ceramic Society
    • /
    • v.20 no.2
    • /
    • pp.153-160
    • /
    • 1983
  • This study was carried out to research the change of mineral phases and the characteristics(apparent specific gra-vity water absorption firing shrinkage modulus of rupture thermal expansion and specific dielectric constant) of the sintered bodies manufactured by kaolin and limestone. Samples were composed of the same theoretical composition as it of anorthite and fired up to 145$0^{\circ}C$ Investigated the change and micro-structure of the mineral phases by XRD and SEM the characterisdtics of the sintered bodies by TMA Automatic Capacitance Bridge and etc. The results were as follow. 1. Reactions of sintering are occurred between 860-95$0^{\circ}C$ and 1200-138$0^{\circ}C$ and state of bloating is occurred at 1410-145$0^{\circ}C$ 2. For the inclusion of feldspar and its fine particles of materials the temperature of producing and collapsing is decreased. 3. Pseudo-wollastonite and gehlenite are formed about 95$0^{\circ}C$ 4. At 114$0^{\circ}C$ anorthite are begin to forming and increase continuously to 138$0^{\circ}C$. Above 141$0^{\circ}C$ content of anorthite are decreased. 5. The variations of bending strength with sintering temperature reflect similar trend of sintered contraction and in-crease continuously from 120$0^{\circ}C$. At 145$0^{\circ}C$ reached about 680kg/cm2. 6. Specific dielectric constant$($\varepsilon$_s)$ of specimen sintered at 141$0^{\circ}C$ is 7.12 and that value is most favorable.

  • PDF

Optimization of Fused Quartz Cantilever DRIE Process and Study on Q-factors (비정질 수정 캔틸레버의 식각 공정 최적화 및 Q-factor 연구)

  • Song, Eun-Seok;Kim, Yong-Kweon;Baek, Chang-Wook
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.2
    • /
    • pp.362-369
    • /
    • 2011
  • In this paper, optimal deep reactive ion etching (DRIE) process conditions for fused quartz were experimentally determined by Taguchi method, and fused quartz-based micro cantilevers were fabricated. In addition, comparative study on Q-factors of fused quartz and silicon micro cantilevers was performed. Using a silicon layer as an etch mask for fused quartz DRIE process, different 9 flow rate conditions of $C_4F_8$, $O_2$ and He gases were tested and the optimum combination of these factors was estimated. Micro cantilevers based on fused quartz were fabricated from this optimal DRIE condition. Through conventional silicon DRIE process, single-crystalline silicon micro cantilevers whose dimensions were similar to those of quartz cantilevers were also fabricated. Mechanical Q-factors were calculated to compare intrinsic damping properties of those two materials. Resonant frequencies and Q-factors were measured for the cantilevers having fixed widths and thicknesses and different lengths. The Q-factors were in a range of 64,000 - 108,000 for fused quartz cantilevers and 31,000 - 35,000 for silicon cantilevers. The experimental results supported that fused quartz had a good intrinsic damping property compared to that of single crystalline silicon.

An Experimental Research on the Standardized Production of Hedge Materials Using Nonwoven Fabric Containers (부직포를 이용한 생울타리 소재 규격생산화의 실험적 연구)

  • 박용진
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.29 no.6
    • /
    • pp.82-91
    • /
    • 2002
  • This study was conducted to investigate methods to overcome serious problems in hedge making. The growth response of Enonymus japonica was investigated, using different sizes of nonwoven fabric containers. Changes of shoot length, fresh weight and chlorophyll contents were measured a period of growth in each size of container. The results of this study are as follows; 1) The maximum growth of shoot length in all treatments was observed in May and August. The significant difference was found in the smaller size of container containing a less amount of soil than the control. 2) The soil amount of rhizosphere for the production of a standardized hedge seemed to be over 2,400-3,600㎤ per plant. 3) The depth of containers had a greater influence on growth of shoot length than the width of containers. 4) The fresh weight in 40cm width containers and 30$\times$20cm containers was similar to the control, but the rest of the containers showed significant difference compared with the control. 5) A significant difference of chlorophyll content was found in A, B, C, D and G treatment but I treatment did not show significant difference at the 5% level.

A Study on the Four-Season Cooling Performance by Color of Water Proofing Membrane Materials Considering the View of Area (지역의 경관을 고려한 도막방수재의 색채별 사계절 차열 및 축열 성능에 관한 연구)

  • Ko, Jin-Soo;Kim, Byung-Yun
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.17 no.2
    • /
    • pp.9-16
    • /
    • 2015
  • This study comparatively analyzed thermal characteristics of the green color, which is currently used the most, and other various colors of a rooftop urethane water proofing sheet. This study also analyzed the cooling performance by color of the water proofing sheet that fused cooling paints, and presented the effective water proofing sheet color for building energy savings. The experimental results are as follows: (1) The value of L (brightness) diminished, and brilliance also became lower from the white color to the black color, and thus, it was confirmed that relatively more heat was absorbed. In a and b chromaticity, which is the color attribute that ignores brightness, no special relationship was identified. (2) Considering that the cooling performance effect is bigger in summer than winter, due to heat reflection, the white water proofing sheet is more effective in building energy savings than the green water proofing sheet that is currently used the most. (3) The water proofing sheet's color has an impact more on cooling performance than the color of the background side of a structure on which water proofing sheet is installed. The experiment object of gray, of which background side is similar to cement mortar, was lower by $5.7^{\circ}C$ than the white background side.

A Study on the Silicone Rubber of Sabot Assembly for the Velocity Multiplication of Mini Ball (소형구의 속도증폭을 위한 사보 조립체의 실리콘고무 특성 연구)

  • Kim, Young-Min;Jin, Doo-Han;Chung, Dong-Teak
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.18 no.4
    • /
    • pp.395-401
    • /
    • 2015
  • A mini ball launch system was developed for the study of dynamic fracture of ceramic materials. The principle of velocity multiplication system is similar to two stage gun. The plastic sabot assembly houses steel plunger and the void filled with silicone rubber. The sabot is stopped by the stopper block then the steel plunger inside the sabot compress the silicone rubber to high pressure. Then the compressive energy of the silicone rubber is transferred to the ball. More than ten times of initial speed was attained. In this study, most effective silicone rubber for the highest final speed was chosen out of three different varieties by launch tests.