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A study on the factors influencing at corner area material thickness changes of rectangular drawing products (각통드로잉 제품의 모서리 재료두께 변화에 영향을 미치는 인자에 대한 해석 연구)

  • Yun, Jae-Woong;Cho, Sang-Hee;Lee, Chun-Kyu
    • Design & Manufacturing
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    • v.14 no.1
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    • pp.22-29
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    • 2020
  • The analysis was carried out using the press molding analysis program by applying six parameters such as material type change, material thickness, friction coefficient, rp, rd and blank holder pressure. As a result of CAE analysis of the soft material DC04 and the relatively hard material HX300LAD, the thickness of the punch R part of the soft material was significantly reduced. The flange portion is greatly increased in thickness in the hard material by the compression action. As a result of considering the deformation amount of 0.6mm, 1.0mm, 1.5mm according to the material thickness, the influence of the thickness is considered to be very small. In case of the material thickness of 0.6mm, the rate of change increases due to the deep drawing depth relative to the material thickness. The sizes of the punches R and die R have the greatest influence on the change in thickness of the material in drawing molding, the smaller the punch R, the thinner the edges of the product, The larger the R of the die, the greater the material thickness of the flange portion. As the coefficient of friction and the blank holder pressure increase, the frictional force of the flange portion increases, which increases the radial force in the drawing process and increases the thickness change of the flange portion.

A Simple, Reliable, and Inexpensive Intraoperative External Expansion System for Enhanced Autologous Structural Fat Grafting

  • Oranges, Carlo M.;Tremp, Mathias;Ling, Barbara;Wettstein, Reto;Largo, Rene D.;Schaefer, Dirk J.
    • Archives of Plastic Surgery
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    • v.43 no.5
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    • pp.466-469
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    • 2016
  • External volume expansion of the recipient site by suction has been proposed as a way of improving fat graft survival. The objective of this study was to present an innovative and simple intraoperative external expansion system to enhance small-volume autologous fat grafting (40-80 mL) and to discuss its background and its mechanism of action. In this system, expansion is performed using a complete vacuum delivery system known as the Kiwi VAC-6000M with a PalmPump (Clinical Innovations). The recipient site is rapidly expanded intraoperatively 10 times for 30 seconds each with a negative pressure of up to 550 mm Hg before autologous fat injection. During this repetitive stimulation, the tissues become grossly expanded, developing macroscopic swelling that regresses slowly over the course of hours following the cessation of the stimulus. The system sets various mechanisms in motion, including scar release, mechanical stimulation, edema, ischemia, and inflammation, which provide an environment conducive for cell proliferation and angiogenesis. In order to maintain the graft construct in its expansive state, all patients are encouraged postoperatively to use the Kiwi three times daily for one minute per session over the course of three days. The handling of this system is simple for both the patients and the surgeon. Satisfactory clinical outcomes have been achieved without significant complications.

An Experimental Evaluation on Flexural Performance of Light-Weight Void Composite Floor using GFRP (GFRP를 이용한 경량합성바닥의 휨성능에 대한 실험적 평가)

  • Ryu, Jae-Ho;Park, Se-Ho;Ju, Young-Kyu;Kim, Sang-Dae
    • Journal of Korean Society of Steel Construction
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    • v.23 no.1
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    • pp.125-135
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    • 2011
  • To obtain a lower story height with a long span and better fire resistance, a new composite floor system using GFRP (glass-fiber-reinforced plastics) was proposed. This floor system consists of asymmetric steel with a web opening, a hollow core ball, concrete, and GFRP. To evaluate the flexural performance of the new composite floor system, an experiment was conducted. The test parameters were the presence of GFRP, the void ratio in relation to the hollow core balls, and the web opening. The test results showed that the resistance and stiffness of the specimen with GFRP were 10% higher than those of the reference specimen, and that fully composite action was accomplished up to the yielding point. After the attainment of the yield strength, the ductility of the specimen was reduced due to the stress concentration around the web openings. The slip between the concrete and steel beam, however, was small. Thus, in the design of the proposed new floor systems, it is desirable that the calculated resistance be reduced by 15%, for safety.

Study on the Effect of a New Antiseptic Preparation ″Swi-Se-Yo″ on the Carry-Over Cocoons in Silk Reeling Process (새로 개발한 조월견방부제 ″쉬세요(Swi-Se-Yo)″의 효과에 관하여)

  • 이장낙;정태암;송기언;하정근
    • Journal of Sericultural and Entomological Science
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    • v.18 no.2
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    • pp.107-110
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    • 1976
  • In silk reeling process the carry-over cocoons must be submerged in the reeling baths filled with reeling water and left until reopening the operation. Under the detention the carry-over cocoons are apt to decay without any antiseptic treatment. Thus an useful antiseptic for the cocoons is urgently needed, and various antseptic agents have been tested for their applicability to the process. However, such an useful agent has not been developed yet. Formalin has been the only chemical used for antisepticizing carry-over cocoons, although it has many defects as the antiseptic for the cocoons. In these circumstances, recently we newly prepared an antiseptic useful for preventing the carryover cocoons from decaying. We named the new antiseptic preparation "Swi-Se-Yo." The Korean term "Swi-Se-Yo" literally means "please take a rest". Through a series of experiments with Swi-Se-Yo we obtained the following results: 1) Swi-Se-Yo, in 0.05% aqueous solution, exerted a good antiseptic effect on the boiled Cocoons submerged in the reeling baths and the effect lasted for 45 hours. The duration of the effect is about two times longer than that of Formalin. 2) The percentage of cocoon reel ability of the carry-over cocoons treated with Swi-Se-Yo was 6% higher than that of Formalin and was equal to that of flowing cold water. 3) The percentage of raw silk yield of the carry-over cocoons treated with Swi-Se-Yo was almost equal to that of Formalin and to that of flowing cold water. 4) The quality of raw silk of the carry-over cocoons treated with Swi-Se-Yo is the same as that of flowing cold water. Besides the above favourable results, Swi-Se-Yo has many advantages as an antiseptic. Chemically it is very stable. Its antimicrobial action is very strong and the spectrum is very broad. It can be available in water-soluble powder and in small bulk. And it is not harmful to human and domestic animals. Considering these profitable properties of Swi-Se-Yo, it will have a good reputation as a carry-over cocoon antiseptic. (The chemical composition and manufacturing method of Swi-Se-Yo will be published in the near future.)

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An Isotopic Study of the Effects of Refining on Fiber

  • FRANCES L WALSH; SUJIT BANERJEE
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2006.06a
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    • pp.31-36
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    • 2006
  • Tritium has been used to directly measure the exchangeable hydrogen in bleached softwood kraft pulp. The hydrogen atoms associated with hydroxyl groups in pulp or with water contained in the pulp can dissociate and exchange with the hydrogen atoms in bulk water. Tritium is a radioactive isotope of hydrogen and behaves almost identically to it. The distribution of tritium between pulp and water ($k_{pw}$) can be easily measured and becomes an index of the protons available fur hydrogen bonding. Bleached kraft pulp was refined in a PFI mill to a range of freenesses. Tritiated water was added and the amount exchanged measured. There was a slight steady increase in $k_{pw}$ until approximately 300 CSF; $k_{pw}$ then rose sharply between 300 CSF and 100 CSF. This rise appears to correlate with FSP. It is likely that the action of refining on the fiber reaches a threshold at about 300 CSF causing the fiber surface to break open creating exponentially more surface area. This theory is visually confirmed through light microscopy. The slow increase in fibrillation of the fibers above 300 CSF correlates with the increase in $k_{pw}$. Beyond the threshold of 300 CSF a dramatic difference in fibrillation is shown, also corresponding with the large increase in $k_{pw}$. The freeness difference around 300 CSF is small, but the change in fiber properties is extreme within this region. This change in properties could lead to sheet breaks and other disruptions when producing products around the threshold. This study leads to a better understanding of how fiber changes during refining, resulting in a practical benefit of target freeness determination. Presently, freeness is selected based on product quality and on some measure of runnability. Yet, there are other considerations, demonstrated by the extreme change in fiber properties around 300 CSF.

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Seismic response of active or semi active control for irregular buildings based on eigenvalues modification

  • Pnevmatikos, Nikos G.;Hatzigeorgiou, George D.
    • Earthquakes and Structures
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    • v.6 no.6
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    • pp.647-664
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    • 2014
  • A reduction of the response of irregular structures subjected to earthquake excitation by control devices equipped by suitable control algorithm is proposed in this paper. The control algorithm, which is used, is the pole placement one. A requirement of successful application of pole placement algorithm is a definition-selection of suitable poles (eigen-values) of controlled irregular structures. Based on these poles, the required action is calculated and applied to the irregular structure by means of control devices. The selection of poles of controlled irregular structure, is a critical issue for the success of the algorithm. The calculation of suitable poles of controlled irregular structure is proposed herein by the following procedure: a fictitious symmetrical structure is considered from the irregular structure, adding vertical elements, such as columns or shear walls, at any location where is necessary. Then, the eigen-values of symmetrical structure are calculated, and are forced to be the poles of irregular controlled structure. Based on these poles and additional damping, the new poles of the controlled irregular structure are calculated. By pole placement algorithm, the feedback matrix is obtained. Using this feedback matrix, control forces are calculated at any time during the earthquake, and are applied to the irregular structure by the control devices. This procedure results in making the controlled irregular structure to behave like a symmetrical one. This control strategy can be applied to one storey or to multi-storey irregular buildings. Furthermore, the numerical results were shown that with small amount of control force, a sufficient reduction of the response of irregular buildings is achieved.

A numerical and theoretical investigation on composite pipe-in-pipe structure under impact

  • Wang, Yu;Qian, Xudong;Liew, J.Y. Richard;Zhang, Min-Hong
    • Steel and Composite Structures
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    • v.22 no.5
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    • pp.1085-1114
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    • 2016
  • This paper investigates the transverse impact response for ultra lightweight cement composite (ULCC) filled pipe-in-pipe structures through a parametric study using both a validated finite element procedure and a validated theoretical model. The parametric study explores the effect of the impact loading conditions (including the impact velocity and the indenter shape), the geometric properties (including the pipe length and the dimensions of the three material layers) as well as the material properties (including the material properties of the steel pipes and the filler materials) on the impact response of the pipe-in-pipe composite structures. The global impact responses predicted by the FE procedure and by the theoretical model agree with each other closely. The parametric study using the theoretical approach indicates the close relationships among the global impact responses (including the maximum impact force and the maximum global displacement) in specimens with the equivalent thicknesses, proposed in the theoretical model, for the pipe-in-pipe composite structures. In the pipe-in-pipe composite structure, the inner steel pipe, together with the outer steel pipe, imposes a strong confinement on the infilled cement composite and enhances significantly the composite action, leading to improved impact resistance, small global and local deformations.

Anti Tumoral Properties of Punica Granatum (Pomegranate) Peel Extract on Different Human Cancer Cells

  • Modaeinama, Sina;Abasi, Mozhgan;Abbasi, Mehran Mesgari;Jahanban-Esfahlan, Rana
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.14
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    • pp.5697-5701
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    • 2015
  • Background: Medicinal plants, especially examples rich in polyphenolic compounds, have been suggested to be chemopreventive on account of antioxidative properties. Punica granatum (PG) (pomegranate) is a well known fruit in this context, but its cytotoxicity in cancer cells has not been extensively studied. Here, we investigated the antiproliferative properties of a peel extract of PG from Iran in different human cancer cells. Materials and Methods: A methanolic extract of pomegranate peel (PPE) was prepared. Total phenolic content(TPC) and total flavonoid conetnt (TFC) were determined by colorimetric assays. Antioxidant activity was determined by DPPH radical scavenging activity. The cytotoxicity of different doses of PPE (0, 5, 20, 100, 250, 500, $1000{\mu}g/ml$) was evaluated by MTT assays with A549 (lung non small cell cancer), MCF-7 (breast adenocarcinoma), SKOV3 (ovarian cancer), and PC-3 (prostate adenocarcinoma) cells. Results: Significant (P<0.01) or very significant (P<0.0001) differences were observed in comparison with negative controls at all tested doses (5-$1000{\mu}g/ml$). In all studied cancer cells, PPE reduced the cell viability to values below 40%, even at the lowest doses. In all cases, IC50 was determined at doses below $5{\mu}g/ml$. In this regard, MCF-7 breast adenocarcinoma cells were the most responsive cells to antiprolifreative effects of PPE with a maximum mean growth inhibition of 81.0% vs. 69.4%, 79.3% and 77.5% in SKOV3, PC-3 and A549 cells, respectively. Conclusions: Low doses of PPE exert potent anti-proliferative effects in different human cancer cells and it seems that MCF-7 breast adenocarcinoma cells are the most cells and SKOV3 ovarian cancer cells the least responsive in this regard. However, the mechanisms of action need to be addressed.

Prognostic Value of Prepro-Gastrin Releasing Peptide in Lung Cancer Patients; NCI-Prospective Study

  • Shafik, Nevine F;Rahoma, M;Elshimy, Reham AA;El kasem, Fatma M Abou
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.12
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    • pp.5179-5183
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    • 2016
  • Background: Prior series investigated the expression of prepro-gastrin releasing peptide (prepro-GRP) in the peripheral blood of lung cancer patients. Our aim was to assess any prepro-GRP role as a prognostic factor for small cell lung cancer (SCLC) and NSCLC and correlations with clinical presentation and treatment outcome. Methods: A prospective study was conducted during the time period from the beginning of January 2012 till the end of January 2014. Prepro-GRP expression was analysed using a nested RT-PCR assay in peripheral blood of 62 untreated lung cancer patients attending the National Cancer Institute (NCI), Cairo University, and 30 age and sex matched healthy volunteers. Results: Among the 62 lung cancer cases, there were 24 (38.7%) SCLC, and 38 (61.3%) NSCLC (10 squamous cell carcinomas, 12 adenocarcinomas, 11 large cell carcinomas, 4 undifferentiated carcinomas, and 1 adenosquamous carcinoma). Twenty six patients (41.9%) were prepro-GRP positive. Prepro-GRP expression was higher (58.3%) among SCLC patients compared to NSCLC (squamous cell carcinoma (15.4%), large cell carcinoma (36.4%), and adenocarcinoma (25%)). Mean OS among prepro-GRP negative cases was longer than that among preprogastrin positive cases (17.6 vs 14.9 months). The mean PFS durations among preprogastrin negative versus positive cases were 7.7 vs 4.6 months (p= 0.041). No difference in response to chemotherapy was identified between the groups (p=0.983). Conclusion: Prepro-GRP is suggested to be a useful prognostic marker for lung cancer patients, especially with the fast- growing, bad prognostic SCLC type. More studies should aim at detailed understanding of the mechanisms of prepro-GRP action and its use in monitoring the response to treatment in a larger cohort.

Effects of Magnetic Pole on Orientation of Bull Sperm Treated by Dithiothreitol or Heparin

  • Pham, Du Ngoc;Shinjo, Akihisa;Kurnianto, Edy
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.2
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    • pp.155-162
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    • 2001
  • Effect of the north (N) or south pole (S) of a magnet and dithiothreitol (DTT) or heparin sodium (H) on the orientation of bull sperm were studied. Sperm were collected from four Japanese Black bulls of Okinawa Prefectural Livestock Experimental Station were treated with various concentrations of DTT or H during the first and sixth days and were then exposed them to N or S with a magnetic field of 3,000 Gauss for 24 hours. Experimental results showed that both N and S significantly increased the perpendicular oriented percentage of bull sperm in most treatments not treated or treated with DTT or H. Anisotropy of magnetic field of bull sperm was the main cause which induced them to orient perpendicular to the magnetic direction. The results of the experiment also showed that, in most cases, the two polarities had the same effect on the orientation of bull sperm. However, in some cases, N exerted a stronger effect on the perpendicular percentage of bull sperm than S, such as with the 20 mM DTT treatment at the first and sixth days and the 100 units H treatment at the sixth day. These cases showed that the perpendicular oriented percentage of bull sperm at N was significantly higher than that of S. It was only the 100 units heparin treatment at S both at the first and sixth days that upward perpendicular orientation was higher than that at N. This might be due to the fact that protamin-DNA structure of a small number of bull sperm nuclei slightly changed because of heparin action.