• Title/Summary/Keyword: Restrained effect

Search Result 243, Processing Time 0.032 seconds

Application of shrinkage prediction models to restraint crack formation in unbonded post-tensioned slabs

  • Gabriela R. Martínez Lara;Myoungsu Shin;Yong-Hoon Byun;Goangseup Zi;Thomas H.-K. Kang
    • Computers and Concrete
    • /
    • v.33 no.4
    • /
    • pp.349-359
    • /
    • 2024
  • This study aims to investigate the effect of restraint configuration on crack formation due to shrinkage-and-creep-induced volumetric change in unbonded post-tensioned slabs. The first part of this study focuses on the comparison of existing shrinkage and creep calculation models that are used to predict the volume-changing behavior of concrete. The second part of this study presents the finite element analysis of a series of architectural configuration prototypes subjected to shrinkage and creep, which comprise unbonded post-tensioned slabs with various restraint configurations. The shrinkage and creep effects were simulated in the analysis by imposing strains obtained from one selected calculation model. The results suggest that a slab up to 300 ft. (90 m) in length does not require a closure strip if it is unrestrained by perimeter walls, and that the most effective restraint crack mitigation strategy for a slab restrained by perimeter walls is a partial wall release.

Research on Relations Between Intermittent Suspension Treatments of irrigation at Different Growing Stages and yields of Paddy Rice (논벼의 생육시기별 간단단수처리와 수확량과의 관계에 관한 연구)

  • 이기춘
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.17 no.3
    • /
    • pp.3795-3814
    • /
    • 1975
  • The purpoes of this thesis is to study the effect of the variation of the beginning date of the suspension of irrigation and the length of intermittent suspension period of irrigation in the paddy field on the growth and yield of rice, so as the provide a critical limit of saving irrigation water and an irrigation method to prevent drough damage in rice cultivation. In this experiment, the rice variety adopted was NONGRIM No.29. There were seven main test plot, each test plot having a different beginning date of the suspension of irrigation. A main test plot was susdivided into five small test plots, each having a different length of the suspension period of irrigation. The results obtained in this experiment are summarized as follows: 1. The number of tillers is controlled by the treatment of the suspension of irrigation, its beginning date being early of late. The reductive effects of beginning dates of suspension upon the number of tillers. investigated on July 30, are about 84% for the treatment suspended on July 8, 87% on July 12, and 92% on July 19, respectively, in comparison with the standard plot. However. the suspenion treatments after the foregoing dates does not affect the control of their numbers. On the other hand, the lengths of intermittent suspension periods influence highly on the number of tillers to be restrained considerably, the decrease ratio ranging from 91% to 80% Both treatments on dates and periods are so intermingled that the restraining effects of suspension periods become greater as the dates of its beginning are earlier. 2. The elongation of plant hieghts also restrained considerably by the longer periods and earlier dates of suspension treatments of irrigation. Especially, the effects of the lengths of suspension periods become more serious. 3. Heading dates are delayed by two to five days through the suspension treatments of irrigation. However, the heading stage ends almost on the same day without relation to the differences between the irrigation suspension treatments. In the test plot where the suspension date of irrigation comes after the young panicle forming stage, the heading stage ends one or two days later than in the standard test plot. 4. Both culm lengths and panicle lengths show significant differences in their values, i.e., their lengths are shorter, as the begining dates of irrigation suspension are earlier and the suspension periods are longer. 5. The earlier the beginning date and the longer the period of irrigation suspension, the less is the number of panicles per hill in comparison with the standard plot. 6. The earlier the beginning date and the longer the period of irrigation suspension, the higher is the significant difference in the number of kernels per panicle in comparison with that in the standard test plot, i.e., the less is the number of kernels per panicle. 7. The earlier the beginning date and the longer the period of irrigation suspension, the lighter are the weights of rough rice and straws per hill in comparison with those in the standard plot.

  • PDF

Study on Effects of the Mixture of Ginseng Radix Rubra, Astragadi Radix and Chrysanthemi Flos (홍삼(紅蔘), 황기, 감국(甘菊) 혼합물(混合物) 제재 효과에 관한 연구)

  • Sung Hyun-Jea;Chung Chong-Un;Ryu Choong-Yul;Her Erk
    • Herbal Formula Science
    • /
    • v.12 no.1
    • /
    • pp.149-157
    • /
    • 2004
  • 1. All the male students and female students who had taken these herb medicines showed a strong increase in immunity (P<0.01) and they were more effective to the male students (P<0.01) rather than the female students (P<0.05) (figure 1). Generally, immunity may be reduced at the time of fatigue and overwork but as these herb medicines have the effect of increasing immunity. Therefore, it is considered that they not only reduce the fatigue of human body but also heighten immunity against disease. 2. The students who had taken these herb medicines showed some reduction in Cortisol concentration in blood, which didn't show the difference of concentration up to statistical meaning compared to before taking the medicines (figure 2). Accordingly, it is regarded that these herb medicine drink restrained stress slightly. 3. The students who had taken these herb medicines showed some reduction in BUN concentration in blood, which didn't show the difference of concentration up to statistical meaning compared to before taking the medicines (figure 3). For the women, they restrained the toxicity of the kidneys just a little. Accordingly, it shows that these medicines are safe herb medicines without the toxicity of the kidneys. 4. The students who had taken these herb medicines didn't show the difference of concentration up to statistical meaning in sFOT and sGPT concentration in blood compared to taking them (figure $4{\sim}5$). Accordingly, it is suggested that these medicines are safe stuffs without the toxity of the liver. 5. Seven members of the university students answered to the questionaire that they were pleasant while taking the medicines and didn't feel fatigue. They answered very positively that they had better effects than before taking the medicines in many things (Refer to the Questionaire). However, one male student and two female students of them complained of temporary headache and indigestion for 2 days after taking these herb medicines but they said they had been taking cold medicines due to cold symptom before taking the medicines. Accordingly, it turns out that such temporary symptom is not irrelevant to these medicines. In conclusion, it is considered that these herb medicines have the effects of increasing immunity, restraining fatigue and stress through this clinical study carried out in simple way and that they are valuable as herb medicines without the toxity of the liver and kidneys.

  • PDF

The Effects of Injinchunggantang on Interferon Signaling Pathway of HepG2 Cells (인진청간탕(茵蔯淸肝湯)이 HepG2 cell의 인터페론 신호전달계에 미치는 영향)

  • Yi, Jong-Hoon;Kim, Young-Chul;Lee, Jang-Hoon;Woo, Hong-Jung
    • The Journal of Internal Korean Medicine
    • /
    • v.26 no.1
    • /
    • pp.74-92
    • /
    • 2005
  • Objectives/Methods : To analyze the effect of Injinchunggantang(IJCGT) to Interferon-${\alpha}/{\beta}$ signal transmission system in HepG2 cells, HepG2 Cell were treated with IJCGT. Also, revelation of MxA, 2'5'-OAS mRNA leaded by Interferon-${\alpha}/{\beta}$ and revelation and activation of Jak1, TYK1, and STAT 1, all main signal transmission factors, were analyzed. Results : The analysis resulted in the following 1. With interferon ${\alpha}/{\beta}$ there was no affect cell propagation of Hep G2 cells. With IJCGT alone, cell propagation of HepG2 was promoted, and cell propagation control function was recovered. 2. With interferon ${\alpha}/{\beta}$ cell death was unaffected. With IJCGT apoptosis of HepG2 cell was restrained, and the cell's reaction to interferon was unaffected. 3. With interferon ${\alpha}/{\beta}$ treatment mRNA revelation of MxA and 2'5'-OAS was induced. When HepG2 cells were injected with IJCGT without interferon ${\alpha}/{\beta}$ treatment, mRNA revelation of MxA and 2'5'-OAS increased in proportion to the treatment density. With pre-treatment of IJCGT, leaded with interferon ${\alpha}/{\beta}$, promoted revelation of MxA, 2'5' -OAS mRNA. 4. Though mRNA revelation of lakl, TYK1 and STAT1 was unaffected with IJCGT, activation of STAT1 was promoted with an increase of phosphorylation of STAT1 protein. With pre-treatment of IJCGT, Jak1, TYK2, STAT1 phosphorylation, leaded with interferon, strengthened. 5. TNF-a, IL-1b and LPS present, revelation of MxA and 2'5'-OAS mRNA leaded by interferon was restrained when HepG2 cells were treated with IJCGT, and the interferon signal transmission system restraint action leaded by inflammatory cytokines was moderated. Conclusion : These results support a role for IJGCT in promotion of anti-virus action through maintainance of the liver's sensibility toward interferon. A clinical study of an interferon treated patient treated also with IJGCT is needed to determine its efficacy.

  • PDF

Seismic vibration control of an innovative self-centering damper using confined SMA core

  • Qiu, Canxing;Gong, Zhaohui;Peng, Changle;Li, Han
    • Smart Structures and Systems
    • /
    • v.25 no.2
    • /
    • pp.241-254
    • /
    • 2020
  • Using confined shape memory alloy (SMA) bar or plate, this study proposes an innovative self-centering damper. The damper is essentially properly machined SMA core, i.e., bar or plate, that encased in buckling-restrained device. To prove the design concept, cyclic loading tests were carried out. According to the test results, the damper exhibited desired flag-shape hysteretic behaviors upon both tension and compression actions, although asymmetric behavior is noted. Based on the experimental data, the hysteretic parameters that interested by seismic applications, such as the strength, stiffness, equivalent damping ratio and recentering capacity, are quantified. Processed in the Matlab/Simulink environment, a preliminary evaluation of the seismic control effect for this damper was conducted. The proposed damper was placed at the first story of a multi-story frame and then the original and controlled structures were subjected to earthquake excitations. The numerical outcome indicated the damper is effective in controlling seismic deformation demands. Besides, a companion SMA damper which represents a popular type in previous studies is also introduced in the analysis to further reveal the seismic control characteristics of the newly proposed damper. In current case, it was found that although the current SMA damper shows asymmetric tension-compression behavior, it successfully contributes comparable seismic control effect as those having symmetrical cyclic behavior. Additionally, the proposed damper even shows better global performance in controlling acceleration demands. Thus, this paper reduces the concern of using SMA dampers with asymmetric cyclic behavior to a certain degree.

The effects of the face reinforcement at shallow tunnels in fractured rock masses (파쇄대 암반에서 얕은 심도의 터널 굴착시 막장보강효과에 관한 연구)

  • Nam, Kee-Chun;Heo, Young;You, Kwang-Ho
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.5 no.4
    • /
    • pp.323-336
    • /
    • 2003
  • Recently, the development of tunnel reinforcement method has been required relating to the shallow tunnelling in soft ground. In this study, the improvement method on tunnel stability is proposed by evaluating the efficiency of face reinforcement which enables to control extrusion of advance core, however, it is often neglected in urban tunnelling under the poor ground conditions. Systematic pre-confinement ahead of the face improves the tunnel stability, subsequently, displacement of the crown and surface settlement can be restrained by proper method. 3-dimensional numerical analysis including horizontal reinforcement modelling on a face is applied to estimate the behaviour of a tunnel in relation to the ground and reinforcement conditions. Consequently, extrusion at the face decreases significantly after using the horizontal reinforcement and the effect of reinforcement is much increased in case of applying the supplemental reinforcement ahead of the face together. Especially, confinement effect around the tunnel and the core is proved by means of the core reinforcement in poor ground conditions.

  • PDF

Curcumin Analogue A501 induces G2/M Arrest and Apoptosis in Non-small Cell Lung Cancer Cells

  • Xia, Yi-Qun;Wei, Xiao-Yan;Li, Wu-Lan;Kanchana, Karvannan;Xu, Chao-Chao;Chen, Da-Hui;Chou, Pei-Hong;Jin, Rong;Wu, Jian-Zhang;Liang, Guang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.16
    • /
    • pp.6893-6898
    • /
    • 2014
  • Curcumin and its analogues have been reported to exert anti-cancer activity against a variety of tumors. Here, we reported A501, a new curcumin analogue. The effect of A501 on cell viability was detected by MTT assay, the result showed that A501 had a better inhibiting effect on the four non-small cell lung cancer (NSCLC) cells than that of curcumin. Moreover, Colony forming experiment showed A501 significant restrained cell proliferation. Flow cytometry displayed A501 can cause G2/M arrest and induce apoptosis. Western blotting showed that A501 decreased the expression of cyclinB1, cdc-2, bcl-2, while increased the expression of p53, cleaved caspase-3 and bax. In conclusion, curcumin analogues A501 played antitumor activity by inhibiting cell proliferation and inducing apoptosis of NSCLC cells. And it was likely to be a promising starting point for the development of curcumin-based anticancer drugs.

Space Charge Behavior of Oil-paper Insulation Thermally Aged under Different Temperatures and Moistures

  • Zhou, Yuan-Xiang;Huang, Meng;Chen, Wei-Jiang;Jin, Fu-Bao
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.3
    • /
    • pp.1124-1130
    • /
    • 2015
  • Moisture and high temperature are the most important factors that lead to the ageing of oil-paper insulation, but the research about space charge characteristics of oil-paper insulation does not take the combined effect of ambient temperature, moisture and thermal ageing into account. The pulsed electroacoustic (PEA) method was used to investigate the influence of moisture and temperature on space charge characteristics of oil paper at different ageing stages. The results showed that moisture could speed up formation of space charge in oil paper when water concentration was low, but the formation was restrained if the water concentration was high. At the beginning of thermal ageing, heterogeneous charge accumulation had predominance, but it gradually changed to homogeneous charge injection with ageing. It was believed that moisture concentration could speed up ageing and enhance charge accumulation on one hand, and accelerate or slow down the establishment speed of space charge on the other hand, therefore, charge accumulation type changed with ageing. The more seriously the oil-paper insulation was thermally aged, the deeper the trap energy level was, hence more space charge was trapped, which could be speeded up by increasing the ageing temperature, but the effect of ambient temperature did not fit the Arrhenius law.

Effect of Growth Regulator Treatments on Growth and Yield of Sweet-potato (생장조절제처리가 고구마의 생육 및 수량에 미치는 영향)

  • Tae-Seok Kim;Don-Kil Lee;Il-Hea Kim
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.14
    • /
    • pp.139-145
    • /
    • 1973
  • Effects of Choline Chloride on growth and yields of sweet-potato cultivated with the single crop and after-barley crop were summarized as follows. 1. The greatest effect was obtained when the sprout-bases of sweet potato were soaked in the solution of Choline Chloride for 24 hours, while the optimum concentration of Choline Chloride was 32.3ppm in case of single crop and 31.1ppm in after barley crop respectively. 2. Choline Chloride restrained the growth of stem; the length shortened and the dry weight decreased. 3. The number of tubers and yields were increased by treating choline chloride. It may be thought that the translocations of assimilation substance from leaves and stem to tubers, was stimulated by treating choline chloride. The tendancy of higher yielding was shown in the early harvesting than in the usual harvesting 4. Sugar and starch content were higher, crude fiber and crude protein content were lower as compared with the control.

  • PDF

Effect of Bonding Condition on the Tensile Properties of Diffusion Bonded Haynes230 (고상확산접합된 Haynes230의 인장성질에 미치는 접합조건의 영향)

  • Kang, Gil-Mo;Jeon, Ae-Jeong;Kim, Hong-Kyu;Hong, Sung-Suk;Kang, Chung-Yun
    • Journal of Welding and Joining
    • /
    • v.31 no.3
    • /
    • pp.76-83
    • /
    • 2013
  • This study investigated the effect of bonding temperature and holding time on microstructures and mechanical properties of diffusion bonded joint of Haynes230. The diffusion bonds were performed at the temperature of 950, 1050, and $1150^{\circ}C$ for holding times of 30, 60, 120 and 240 minutes at a pressure of 4MPa under high vacuum condition. The amount of non-bonded area and void observed in the bonded interface decreased with increasing bonding temperature and holding time. Cr-rich precipitates at the linear interface region restrained grain migration at $950^{\circ}C$ and $1050^{\circ}C$. However, the grain migration was observed in spite of short holding time due to the dissolution of precipitates to base metal in the interface region at $1150^{\circ}C$. Three types of the fracture surface were observed after tensile test. The region where the coalesce and migration of grain occurred much showed high fracture load because of base metal fracture whereas the region where those did less due to the precipitates demonstrated low fracture load because of interface fracture. The expected fracture load could be derived with the value of fracture area of base metal ($A_{BF}$) and interface ($A_{IF}$), $Load=201A_{BF}+153A_{IF}$. Based on this equation, strength of base metal and interface fracture were calculated as 201MPa and 153MPa, respectively.