• Title/Summary/Keyword: pre-cut

Search Result 225, Processing Time 0.024 seconds

Performance Comparison of Butterfly Joints between Manual Member and Pre-cut Member (수가공 및 기계가공 된 나비장 접합부의 성능 비교)

  • Kim, Gwang-Chul;Kim, Jun-Ho
    • Journal of the Korea Furniture Society
    • /
    • v.27 no.3
    • /
    • pp.165-174
    • /
    • 2016
  • To modularize the joints of Hanok, the bending strengths of butterfly joints between pre-cut and manual member were compared. Structural size joints were manufactured and the length, width and thickness of each tenon were produced with different sizes. The ultimate load of pre-cut members was 2 times higher than that of manual members. Degree of anchorage for the joints on pre-cut member was also superior to that of manual member. By the F-test results, a great influence between ultimate load and sizes of tenon was found. In result of multiple regression analysis, the length and thickness of tenon were showed proportion relationships with the ultimate load, but the width of tenon was showed inverse proportion with the ultimate load. The results of this study can be used to identify the relationships among the major influence factors. Futhermore, it might be used as basic data for modularization the joints of Hanok.

A Tunnel Blasting Method Favorable to the Environment, which Utilizes Pre-splitting & an Upper Center Cut. (선균열과 상부 심빼기를 이용한 환경 친화적 터널발파공법)

  • 김일중;김영석;기경철
    • Explosives and Blasting
    • /
    • v.20 no.2
    • /
    • pp.7-19
    • /
    • 2002
  • The cut is placed high up in the section, the 1st sloping holes below the cut, and divided all the holes located below the 1st sloping holes into a certain area with longitudinal section, to lower pollution made from tunnel blasting. With the sequential blasting machine, after I first blasted holes around the cut holes by a pre-splitting method, blasted the cut area and the 1st sloping holes. The 1st and 2nd sloping holes divided areas are initiated gradually to free face upwards made by the cut. Especially, I pre-splinted contour holes previous blast the before sloping holes from the contours. The ground vibration from the earth surface just over the advance face decreased about 42.0% compare with the down blasting method under the condition of equal charge weight per delay. I controlled the crack and over break of the mother rock by pre-splitting contour holes before blast the first sloping holes from the contours. The peak values of noise and air blast by blasting decreased about 10dB more than the down blasting method. the noise and air blast diminished gradually as a round. The throw distance of the fly rock was decreased about 55%.

Temperature Effect on Tensile Strength of Filled Natural Rubber Vulcanizates (가황 천연고무의 인장강도에 미치는 온도의 영향)

  • Ko, Young-Chon;Park, Byung-Ho
    • Elastomers and Composites
    • /
    • v.36 no.4
    • /
    • pp.255-261
    • /
    • 2001
  • This study was related with the effect of elevated temperature on the tensile strength of edge-cut samples. There was a different tensile strength behavior of uncut samples and pre-cut samples under different test temperatures. Tensile strength of uncut sample decreases with increasing test temperature. When pro-cut size(C) is larger than critical cut size($C_{cr}$), tensile strength or pre-cut specimen at $80^{\circ}C$ is higher than that of pre-cut specimen at room temperature (RT). Test specimens under $80^{\circ}C$ condition exhibited more secondary cracks at the crack tip region compared to room temperature conditions. However, secondary cracks of pre-cut specimens are not clearly developed at $110^{\circ}C$. Differences in tensile strength induced by different test temperature seem to be responsible for the strain-induced crystallization and micro-cracking patterns.

  • PDF

Performance Comparison of Korean Tongue and Groove Joint between Hand-made and Pre-cut (주먹장 접합부의 수가공과 기계가공의 성능비교)

  • Kim, Gwang-Chul;Kim, Jun-Ho
    • Journal of the Korean Wood Science and Technology
    • /
    • v.44 no.5
    • /
    • pp.664-676
    • /
    • 2016
  • Recently, the demand on the Hanok have been increased with social change. However, Hanok has a major problem of a rising costs caused by hand-made process. So, performance comparison between hand-made process and pre-cut process was conducted to modularize the joints in Hanok. Douglas-fir was used to manufacture the structural size dovetail joints by hand-made and pre-cut precess. The bending strengths on joints with two process were evaluated. The average ultimate load of pre-cut joints was 1.5 times higher than that of hand-made joints. F-test results in both process showed a great relationships between ultimate load and tenon's size variation. The length and thickness of tenon showed a proportional relationship with the ultimate load, but the tenon width showed inverse proportion with the ultimate load. This results may be used as basic data for the joint modularization of Hanok.

Effect of arranging Angles and Sucrose Concentration on Vase life and Quality of Cut Rose 'Marina' (삽지각도와 Sucrose 농도가 절화 장미의 수명과 품질에 미치는 영향)

  • Song, Chae Eun
    • FLOWER RESEARCH JOURNAL
    • /
    • v.19 no.3
    • /
    • pp.151-157
    • /
    • 2011
  • This research was aimed to extend the vase life and improve the quality of cut roses 'Marina'. This study investigated the effect of three different angles and sucrose concentration on the vase life and the quality of cut rose flowers. In first experiment, cut roses were placed in three different angles ($0^{\circ}$, $45^{\circ}$ and $90^{\circ}$) in holding solutions containing 0.5, 1 and 2% sucrose (soaking treatment), and examined the number of petals of cut roses. In second experiment, cut roses were placed in three different angles after pre-treated in 0, 1, 2 and 4% sucrose solution for 2 and 20 hours, and examined the flower diameter of cut roses. In third experiment, cut roses were examined the pigmentation, flowing response and chlorophyll contents in cut roses by three different angles after pulsing treatment (pre-treatment) in holding solution containing 2% sucrose for 2 and 20 hours. Results of this study showed that cut roses were influenced by arranging angles and sucrose concentrations. The vase life of cut roses were extended in $45^{\circ}$ and $90^{\circ}$ arranging angle, as compared with the control (distilled water), and the holding solution containing 2% sucrose significantly increased vase life of cut roses(P < 0.05). Flower diameter of cut roses pre-treated in 4% sucrose solution for 2 and 20 hours significantly decreased (P < 0.05). The pigmentation and flowing response in cut roses were beneficial in $45^{\circ}$ arranging angle treated with 2% sucrose solution for 2 and 20 hours. Chlorophyll content in leaves of cut roses was not influenced by arranging angles. The pigmentation and flowing response of $0^{\circ}$ and $45^{\circ}$ arranging angles were better than that of 90 arranging angle. The vase life of cut roses in $45^{\circ}$ arranging angle was more prolonged than that in $90^{\circ}$ arranging angle. In conclusion, the arranging angles seem to be effective in retarding senescence of cut rose flowers.

Seismic analysis and dynamic behavior characterization of rib-reinforced pre-cast tunnels (리브 보강 프리캐스트 터널의 내진 해석 및 동적거동 특성 파악)

  • Song, Ki-Il;Jung, Sung-Hoon;Cho, Gye-Chun
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.11 no.3
    • /
    • pp.287-301
    • /
    • 2009
  • The novel cut-and-cover tunnel construction method using rib-reinforced pre-cast arch segments has been recently developed and applied for practice to secure a structural stability of high covering and wide width section tunnels. Cut-and-cover tunnels are usually damaged by the seismic behavior of backfill grounds in case of a low covering condition. Seismic analyses are performed in this study to characterize the dynamic behavior of rib-reinforced pre-cast arch cut-and-cover tunnels. Seismic analyzes for 2 lane cast-in-place and rib-reinforced pre-cast arch cut-and-cover tunnels are carried out by using the commercial FDM program (FLAC2D) considering various field conditions such as the covering height embankment slope and excavation slope. It can be concluded that the amplification of seismic wave is reduced due to an increase in the structural stiffness induced by rib-reinforcement. The results show that the rib-reinforced pre-cast arch cut-and-cover tunnels are more effective against the seismic loading, compared to the cast-in-place cut-and-cover tunnels.

Robust Extraction of Lean Tissue Contour From Beef Cut Surface Image

  • Heon Hwang;Lee, Y.K.;Y.r. Chen
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 1996.06c
    • /
    • pp.780-791
    • /
    • 1996
  • A hybrid image processing system which automatically distinguished lean tissues in the image of a complex beef cut surface and generated the lean tissue contour has been developed. Because of the in homegeneous distribution and fuzzy pattern of fat and lean tissue on the beef cut, conventional image segmentation and contour generation algorithm suffer from a heavy computing requirement, algorithm complexity and poor robustness. The proposed system utilizes an artificial neural network enhance the robustness of processing. The system is composed of pre-network , network and post-network processing stages. At the pre-network stage, gray level images of beef cuts were segmented and resized to be adequate to the network input. Features such as fat and bone were enhanced and the enhanced input image was converted tot he grid pattern image, whose grid was formed as 4 X4 pixel size. at the network stage, the normalized gray value of each grid image was taken as the network input. Th pre-trained network generated the grid image output of the isolated lean tissue. A training scheme of the network and the separating performance were presented and analyzed. The developed hybrid system showed the feasibility of the human like robust object segmentation and contour generation for the complex , fuzzy and irregular image.

  • PDF

Experimental Testing and Finite Element Modelling of Steel Columns Weakened to Facilitate Building Demolition

  • van Jaarsveldt, W.J.;Walls, R.S.;van der Klashorst, E.
    • International journal of steel structures
    • /
    • v.18 no.5
    • /
    • pp.1483-1496
    • /
    • 2018
  • Negligible research has been conducted to date on how to analyse weakened columns, thus safety risks are still involved when structures are weakened prior to demolition. There are various methods available for demolishing steel structures. One of the most effective methods that has been developed involves pre-cutting steel columns at a certain height, so that the least effort can be used to collapse the structure by means of pulling out some of the columns. This paper presents (a) an experimental setup developed to test the capacity of axially loaded weakened columns, which is used to (b) validate a finite element (FE) model. The two pre-cuts that are presented in this paper are (1) the double window cut and (2) the triangular window cut, which are both commonly used in industry. A column weakened with a double window cut or triangular window cut reduces the axial load capacity by up to 50 and 40%, respectively. The FE models developed predict the axial failure load of weakened columns for a double window cut and triangular window cut are generally within an accuracy of less than 8 and 10%, respectively. It is shown at higher slendernesses the influence of column cuts is less than would be intuitively expected because global buckling becomes dominant.

Effects of pre-heat treatments on the quality of cut kimchi cabbages during short-term storage (절단배추의 단기 저장에 대한 예열처리 효과)

  • Kim, Sang-Seop;Ku, Kyung-Hyung;Jeong, Moon-Cheol;Hong, Joo-Heon;Chung, Shin-Kyo
    • Food Science and Preservation
    • /
    • v.21 no.6
    • /
    • pp.776-783
    • /
    • 2014
  • Kimchi cabbages were cut ($3{\times}3cm$), and were pre-heat treated at $40^{\circ}C$, and their physicochemical qualities and browning degrees were investigated during 8 weeks storage at $5^{\circ}C$. The Cut kimchi cabbages were treated at $40^{\circ}C$ (1~8 hrs) and their protein bands profiles were determined by sodium dodecyl sulfate polyacrylamide electrophoresis (SDS-PAGE). The 60, 39, 33, and 12 kDa bands considered heat shock proteins (HSPs) were expressed in the cut kimchi cabbage, and the 4-hr pre-heat treatment (HS 4) exhibited the strongest band ratio. The weight ratios and titratable acidities of the pre-heat treated cut kimchi cabbages were not changed so much after 8 weeks storage at $5^{\circ}C$, and the soluble solid contents of HS 4 decreased less than that of any other treatments. The browning degree of HS 4 after 8 week storage was also shown to be the least among the treatments. The polyphenol oxidase (PPO) activities of all treatments slightly rose during the over all storage period, in contrast with the decrease of total phenolic contents. The expression of HSPs was identified in the pre-heat treated cut kimchi cabbages, and HS 4 exhibited the best quality and appearance after 8 weeks storage at $5^{\circ}C$.

Consumption and Satisfaction with Fresh-Cut Produce in Korean Adults (신선편의 농산물 소비 현황 및 만족도 조사)

  • Bae, Yun-Jung;Yu, Kwang-Won;Lee, Kyung-Haeng
    • The Korean Journal of Food And Nutrition
    • /
    • v.35 no.2
    • /
    • pp.150-158
    • /
    • 2022
  • The purpose of this study was to assess consumption and satisfaction with fresh-cut produce in Korean adults. In this study, an online survey November 9~13, 2020 was conducted with 982 Korean adults age 19~64 (490 males and 492 females) with experience in purchasing fresh-cut produce in the past year. Among all respondents, the percentage with experience in buying 'washed or peeled vegetables' was the highest (71.18%), followed by those in buying 'packaged salads/sprouts/ssam vegetables' (64.15%), 'pre-cut fruits/fruit cups' (59.98%), 'pre-cut or minced vegetables' (56.01%), and 'washed or peeled fruits' (53.67%), respectively. Among the types of fresh-cut produce, 'packaged salads/sprouts/ssam vegetables' showed the highest satisfaction score at 3.73 pts, and the overall satisfaction score of fresh-cut produce consumption was also 3.73 pts. Compared to male respondents, female respondents showed a significantly higher percentage of respondents that purchased 'packaged salads/sprouts/ssam vegetables' (p=0.0409), significantly higher satisfaction scores (p=0.0124), and a higher percentage of respondents considering 'freshness' important when purchasing (p<0.0001). Additionally, the group with high household income comprised a significantly higher ratio of respondents considering 'eco-friendly or organic status' important. The study results may facilitate identify areas for improvement of fresh-cut produce in the future.