• Title/Summary/Keyword: Extension Surface

Search Result 655, Processing Time 0.029 seconds

Effect of Concrete Surface Coating on the Service Life Extension (콘크리트 표면도장에 의한 내구수명 연장효과)

  • Kim, Ki-Hyun;Cha, Soo-Won;Jang, Seung-Yup
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2010.05a
    • /
    • pp.193-194
    • /
    • 2010
  • Developed is a chloride penetration analysis program that can consider a concrete surface coating. The effect of concrete surface coating on the service life is simulated by the developed finite element program. It was revealed that the coating at the earlier age is the more effective way to extend the service life.

  • PDF

Comparison of the Surface Chemical Properties of Plastic Film House, Upland, and Orchard Soils in Gyeongbuk Province

  • Park, Sang-Jo;Park, Jun-Hong;Kim, Chan-Yong;Seo, Young-Jin;Kwon, Oh-Heun;Won, Jong-Gun;Lee, Suk-Hee
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.49 no.2
    • /
    • pp.115-124
    • /
    • 2016
  • The objectives of this study were to evaluate the soil fertility about plastic film house, upland, and orchard in Gyeongbuk Province, Korea. The surface chemical properties of soil samples were investigated every 4 year from 2000 year at upland, 2001 year at orchard, and 2002 year at plastic film house. During 12 year's monitoring, mean soil pH was increased by 0.7 and 0.8 pH unit from pH 5.7 in upland and orchard, respectively, 0.5 pH unit from pH 6.5 in plastic film house. About 50% of all the field samples occupied within the recommended pH range (pH 6-7). Although soil organic matter (SOM) was gradually increased by about $10g\;kg^{-1}$ for 12 years, 40% of orchard, 49% of plastic film house, and 77% of upland soil samples were still below the 3% SOM. The mean concentration of available phosphate for 12 years in upland, orchard, and plastic film house were 530, 600, and $760mg\;kg^{-1}$, respectively. The relative frequencies exceeding the recommended available phosphate range ($300-550mg\;kg^{-1}$) were 43%, 53%, and 66% at upland, orchard, and plastic film house soils, respectively. $NH_4OAc$ exchangeable $K^+$ of upland, orchard, and plastic film house in the last soil test were 0.8, 0.9, and $1.6cmol_c\;kg^{-1}$, respectively. The relative frequencies above the recommended K level were 56% and 70% of orchard and plastic film house soil samples, respectively. The levels of crop nutrients except exchangeable Ca and Mg in upland soil were tended to increase gradually in the three fields. Exchangeable Mg, EC, available phosphate, organic matter and soil pH could be used as principle components to differentiate the chemical properties of three land fields. This analysis revealed that the soil fertility was affected by cropping method and field management, although additional research is needed to assess the importance of management on soil chemical properties and many fields indicate an opportunity for improvement in fertilizer management.

Comparison of BOD, COD, TOC and DOC as the Indicator of Organic Matter Pollution of Agricultural Surface Water in Gyeongnam Province

  • Lee, Seong-Tae;Lee, Young-Han;Hong, Kwang-Pyo;Lee, Sang-Dae;Kim, Min-Kyeong;Park, Jong-Hwan;Seo, Dong-Cheol
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.46 no.5
    • /
    • pp.327-332
    • /
    • 2013
  • This survey was conducted to obtain basic data about organic matter such as BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), DOC (Dissolved Organic Carbon) and TOC (Total Organic Carbon) in agricultural water in Gyeongnam province. BOD and COD are currently used for water quality indices, but adoption of TOC is being suggested. The surface water samples were collected at 39 locations in Gyeongnam province in April, July and October. Average concentrations of BOD, COD, DOC and TOC were 1.6, 3.3, 5.3 and $5.7mg\;L^{-1}$, respectively. In July, average concentrations of BOD and COD were 2.4 and $3.9mg\;L^{-1}$, respectively, showing these values were higher than other months. Average concentrations of TOC in April, July and October were 4.8, 7.4 and $4.8mg\;L^{-1}$, respectively. This suggested that the highest value of TOC was in July. Average decomposition efficiencies for BOD-C/TOC and COD-C/TOC were 11.4 and 23.9%, respectively. Correlation coefficient of TOC and DOC was higher by 0.995, whereas that of TOC and COD was lower by 0.763. Especially, TOC and DOC were highly related than others.

The Structural Behavior of $700kg/cm^2$ High Strength Concrete Frames Considering Extension Distances at Joints (내민길이를 고려한 $700kg/cm^2$ 고강도 콘크리트 골조의 구조적거동)

  • 신성우;안종문;윤영수;이승훈
    • Magazine of the Korea Concrete Institute
    • /
    • v.6 no.5
    • /
    • pp.140-148
    • /
    • 1994
  • RCI 318-8!4 recommends that when the specified cornpresslve strength of concrete In a column is greater than 1.4 times thdt spec~f~ed for a floor svsttm. top surface of the colunm concrete shall extend 2ft(600mm) into the slab from the face of colurnn to avoid unexpected brittle failure. Six test specimens were cast arid tested on 2/3 scale frame specmiens havlng different extension distances and compressive strength of concrete as the major variables. The paper discusses the performance of the frames in terms of ductility and also presents the assessment of the ACI 318-89 provisions.The test results showed that the ductility index were incrrased with increasing of compressive strength of concrete and extension distance. And top surface of the column concrete should extend 2h(h overall depth of beam) into the beam from the face of the column to avoid unexpected brittle failure in frame.

An Improved Tracing algorithm for surface/surface intersection (곡면간의 교차곡선 계산을 위한 개선된 Tracing 알고리즘)

  • 조두연;이규열;임중현
    • Korean Journal of Computational Design and Engineering
    • /
    • v.4 no.3
    • /
    • pp.269-283
    • /
    • 1999
  • Surface/surface intersection is a common and important problem in geometric modeling and CAD/CAM. Several methods have been used to approach this problem. All possible intersection curves can be obtained by using the subdivision algorithm, while it requires a great deal of memory and is somewhat inefficient. The tracing algorithm is much faster than the subdivision algorithm, and can find points on the intersection curve sequentially. But, the tracing algorithm has some problems in the intersection curves on surface boundaries. In this paper, an Improved tracing algorithm that includes some ideas such as a new trace-terminating condition for the intersection curves on surface boundaries, detecting closed intersections and extension for composite surfaces is suggested. This algorithm consists of three step: generating state points for curve tracing, tracing intersection curves and sorting pieces of the intersection curves. The results of this algorithm and comparisons to the 'DESIGNBASE' and 'ACIS' system are presented.

  • PDF

Arthroscopic-assisted Reduction and Percutaneous Screw Fixation for Glenoid Fracture with Scapular Extension

  • Kim, Se Jin;Lee, Sung Hyun;Jung, Dae Woong;Kim, Jeong Woo
    • Clinics in Shoulder and Elbow
    • /
    • v.20 no.3
    • /
    • pp.147-152
    • /
    • 2017
  • Background: To evaluate the clinical and functional outcomes of arthroscopic-assisted reduction and percutaneous screw fixation for glenoid fractures with scapular extension, and investigate the radiologic and clinical benefits from the results. Methods: We evaluated patients treated with arthroscopic-assisted reduction and percutaneous screw fixation for glenoid fractures with scapular extension from November 2008 to September 2015. Fractures with displacement exceeding one-fourth of the anterior-articular surface or more than one-third of the posterior-articular surface in radiographic images were treated by surgery. Clinical assessment was conducted based on range of motion, Rowe score, and Constant score of injured arm and uninjured arm at last follow-up. Results: Fifteen patients with Ideberg classification grade III, IV, and V glenoid fracture who underwent arthroscopic-assisted reduction using percutaneous screw fixation were retrospectively enrolled. There were no differences in clinical outcomes at final follow-up compared to uninjured arm. Bone union was seen in all cases within five months, and the average time to bone union was 15.2 weeks. Ankylosis in one case was observed as a postoperative complication, but the symptoms improved in response to physical therapy for six months. There was no failure of fixation and neurovascular complication. Conclusions: We identified acceptable results upon radiological and clinical assessment for the arthroscopic-assisted reduction and percutaneous fixation. For this reason, we believe the method is favorable for the treatment of Ideberg type III, IV, and V glenoid fractures. Restoration of the articular surface is considered to be more important than reduction of fractures reduction of the scapula body.

The Effect of The Flexural Strength Ratio on Beam-Column Joint with High and Low Strength Concrete (고강도와 보통 강도 콘크리트를 사용한 보-기둥 접합부의 휨강성화에 따른 이력거동)

  • Shin, S.W.;An, J.M.;Moon, J.I.;Kim, D.K.;Lee, K.S.;Park, H.M.;Lee, S.H.;Oh, J.G.
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1992.10a
    • /
    • pp.185-190
    • /
    • 1992
  • ACI318-89 Recommended that when the specified compressive strength of concrete in a column is greater than1.4 times that specified for a floor system, top surface of the column concrete shall extend 2ft(600mm)into the slab from the face of column to avoid unexpected brittle failure. The major variables are extension distance, flexural strength ratio(Mr), and shear reinforcement ratio(Vs). Test results are as follows ; (1) The failure modes of specimens under cyclic loading were concentrated at critical region from beam-column joint face. (2) Ductility index($\mu$f) were increased with increasing of shear confinement ratio and flexural strength ratio. (3)The specimens with 2ft extension distance showed more ductility than the specimens with 1ft extension distance.

  • PDF

Separation and Quantification of Parasitic Resistance in Nano-scale Silicon MOSFET

  • Lee Jun-Ha;Lee Hoong-Joo;Song Young-Jin;Yoon Young-Sik
    • KIEE International Transactions on Electrophysics and Applications
    • /
    • v.5C no.2
    • /
    • pp.49-53
    • /
    • 2005
  • The current drive in a MOSFET is limited by the intrinsic channel resistance. All other parasitic elements in a device structure perform significant functions leading to degradation in the device performance. These other resistances must be less than 10$\%$-20$\%$ of the channel resistance. To meet the necessary requirements, the methodology of separation and quantification of those resistances should be investigated. In this paper, we developed an extraction method for the resistances using calibrated TCAD simulation. The resistance of the extension region is also partially determined by the formation of a surface accumulation region that gathers below the gate in the tail region of the extension profile. This resistance is strongly affected by the abruptness of the extension profile because the steeper the profile is, the shorter this accumulation region will be.

Identification of the Relationship between Surface Variations of Lower Body Parts by Movement Using 3D Scan Data - A Focus on Women Aged 20 to 24 Years - (3D 스캔데이터를 활용한 동작에 따른 하반신 주요 부위별 체표면 변화 및 상관관계 - 20-24세 여성을 중심으로 -)

  • Lee, So-Young;Kim, Ji Min
    • Journal of the Korean Society of Costume
    • /
    • v.67 no.3
    • /
    • pp.81-98
    • /
    • 2017
  • The purpose of this study is to provide basic information for the development of pants patterns with a high level of fit and comfort through calculating surface variations of lower body parts by movement, grouping them into factors, and analyzing how their surface variations link to one another. The achieved results will help determine essential elements for constructing pants patterns, such as key measurements of lower body parts, the amount of ease values and selection of fabrics, which should be taken into consideration for allowing better movement in clothing. The study required lower body 3D scanning of women for analysis, and 13 women between the ages of 20-24 participated in the scanning, which was done by using Artec Eva 3D scanner. Their scanned data were digitalized and converted to measure the values of their lower body surface length and girth in pre-determined positions such as walking, stair climbing and sitting on a chair. These measurements have been statistically analyzed through SPSS 21.0 to obtain the average amounts and rates of extension for each of the measurement item. Some of the highlighted study results are as follows: The surface length and girth measurements were grouped into 4 factors based on their average extension rates. The results from correlation analysis between measurement items within each factor demonstrated that common items linked to all the changes in the values of other items in the three movements. But in most cases, items were not always correlated with each other for different movements. The results also showed that there were correlations between girth measurements, length measurements, and girth and length measurements. Therefore, key measurements for daily pants should be determined within reasonable estimations between relevant measurement items, while the measurements for work pants, which often withstand certain postures or repetitive movements, may require measurement items that are appro priate for, and closely related to, certain movements or tasks.