http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Y.F. Luo,Y.P. Liu,Z. Y. HU,Z. Xiong 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.3
The traditional mode superposition method (MSM) is inefficient when applied to dynamic analyses of spatial lattice structures. The inapplicability and inefficiency of the MSM associated with spatial lattice structures are investigated and summarized in this paper. Based on mode selection and mode construction, a new modal set is constructed named Eigen- Loaddependent Ritz (Eigen-LDR) mode. Additionally, the computational procedure of the Eigen-LDR modes is presented. Furthermore, based on the constructed Eigen-LDR modes, a modified MSM, named the Eigen-LDR mode superposition method (EL-MSM), is proposed. Two typical spatial lattice structures, namely, a latticed shell and a spatial truss, are built as numerical examples. Seismic response analyses using the EL-MSM, including mode-superposition time history analysis and mode-superposition response spectrum analysis, are conducted simultaneously. The numerical results illustrate the accuracy, efficiency and generality of the method proposed in this paper.
EFFECTS OF ALTITUDE ON COMBUSTION CHARACTERISTIC DURING COLD START OF HEAVY-DUTY DIESEL ENGINE
Z. C. KAN,D. M. LOU,Z. Z. CAO,Z. Y. HU,S. LIU,Z. H. YANG 한국자동차공학회 2017 International journal of automotive technology Vol.18 No.2
Altitude has a significant effect on combustion of heavy-duty diesel engines, especially during cold start. An experimental study on a heavy-duty diesel engine operating at different altitudes was conducted. Tests were based on a direct injection (DI) turbocharged diesel engine with intake and exhaust pressure controlled by the plateau simulation test system to stimulate altitude conditions including 0 m, 1000 m, 2000 m, 3000 m and 4000 m. Results indicated that the compression and expansion resistance moment reduced and the speed increased during the cranking period. The peak pressure of several cycles was increased during the start-up period; however, the expansion pressure dropped more and the indicated mean effective pressure (IMEP) reduced as the altitude rose. While at an altitude of over 2000 m, the peak pressure fluctuated obviously during the start-up period. The higher the altitude was, the more the fluctuation amplitude and cycle number increased and combustion instability enhanced, which resulted the start-up period time increasing at high altitude. When the altitude rose, the cycle-to-cycle variation of the peak pressure and speed fluctuation increased during the idle, the ignition and CA50 were delayed and the combustion duration was shortened. The effect of altitude on combustion characteristics of the diesel engine was more significant during the start-up period than during its idle period.
CFD CONFIRMATION OF ABNORMAL SHOCK WAVE INTERACTIONS
Z.M. Hu(후종민),Y.R. Yang(양영록),Y. Zhang(장유),R.S. Myong(명노신),T.H. Cho(조태환) 한국전산유체공학회 2008 한국전산유체공학회 학술대회논문집 Vol.2008 No.-
For the Mach reflection of symmetric shock waves, only the wave configuration of an oMR(DiMR+DiMR) is theoretically admissible. For asymmetric shock waves, an oMR(DiMR+InMR) will be possible if the two slip layers assemble a convergent-divergent stream tube while an oMR(InMR+InMR) is absolutely impossible. In this paper, an overall Mach reflection configuration with double inverse MR patterns is confirmed using the CFD technique. Classical two- and three-shock theories are also applied for the theoretical analysis. In addition, oscillations of shock wave patterns are computed for the interaction of a hypersonic flow and double-wedge-like geometries.
Hu, Y.D.,Lan, D.,Zhu, Y.,Pang, H.Z.,Mu, X.P.,Hu, X.F. Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.8
Objective: A 28-d trial was conducted to evaluate the effect of diets with different energy and lipase levels on performance, nutrient digestibility, serum profiles, gut health, and carcass quality in broilers. Methods: A total of 720 one-day-old male Ross 308 broilers ($45.4{\pm}0.5g$) were randomly assigned to one of the following four treatments: i) RET, reduced energy treatment (metabolizable energy = 2,950 and 3,100 kcal/kg for starter and finisher diet), ii) BDT, basal diet treatment (metabolizable energy = 3,050 and 3,200 kcal/kg for starter and finisher diet, iii) RET015, RET+0.15 g/kg lipase, and iv) RET03, RET+0.3 g/kg lipase. There were 10 replications (cages) per treatment with 18 birds per cage. Results: During d 1 to 14, broilers fed BDT, RET015, and RET03 diets had higher (p<0.05) body weight gain than those fed RET diet. During d 1 to 14, 15 to 28 and the overall experiment, feed conversion ratio in RET03 treatment was lower (p<0.05) compared with RET treatment. On d 14, the apparent total tract digestibility (ATTD) of dry matter (DM), ether extract (EE), and gross energy in RET03 treatment was higher (p<0.05) than those in RET treatment, while the ATTD of N was increased (p<0.05) by RET03 treatment. On d 28, broilers fed RET03 diet had higher (p<0.05) ATTD of DM than those fed RET and RET015 diets, while the ATTD of EE in BDT and RET03 treatments was increased (p<0.05) compared with RET and RET015 treatments. Broilers fed RET03 diet had higher villus height (VH) and VH:crypt depth (CD) ratio than those fed RET and BDT diets. The activity of pancreatic lipase in BDT and RET03 treatments was higher (p<0.05) than that in RET treatment. Conclusion: Taken together, lipase supplementation (3,000 U/kg feed) increased growth performance, nutrient digestibility, VH, VH:CD ratio and lipase activity, but decreased triglyceride, low-density lipoprotein cholesterol and the abdominal fat percentage in broilers fed reduced energy diet.
Y. Li,Y.L. Pei,R.Q. Hu,Z.M. Chen,Y. Zhao,Z. Shen,B.F. Fan,J. Liang,G.Wang 한국물리학회 2014 Current Applied Physics Vol.14 No.7
We have investigated the electrical performance of amorphous indiumegalliumezinc oxide (a-IGZO) thin-film transistors with various channel thicknesses. It is observed that when the a-IGZO thickness increases, the threshold voltage decreases as reported at other researches. The intrinsic field-effect mobility as high as 11.1 cm2/Vs and sub threshold slope as low as w0.2 V/decade are independent on the thickness of a-IGZO channel, which indicate the excellent interface between a-IGZO and atomic layer deposited Al2O3 dielectric even for the case with a-IGZO thickness as thin as 10 nm. However, the source and drain series resistances increased with increasing of a-IGZO channel thickness, which results in the apparent field-effect mobility decreasing. The threshold voltage shift (DVth) under negative bias stress (NBS) and negative bias illumination stress (NBIS) were investigated, also. The hump-effect in the sub threshold region under NBS and threshold voltage shift to negative position under NBIS were enhanced with decreasing of a-IGZO channel thickness, owing to the enhancement of vertical electrical field in channel.
Applications of conservation integral to indentation with a rigid punch
Xie, Y.J.,Lee, K.Y.,Hu, X.Z.,Cai, Y.M. Pergamon Press ; Elsevier Science Ltd 2009 Engineering fracture mechanics Vol.76 No.7
When a substrate of the brittle material is indented by a relatively rigid, square-ended punch, a singular stress field and K-dominant region will arise at the near-surface adjacent to the punch corners. The singularity of this stress field is identical with the mode I crack. The stress intensity factor in this case represents the intensification of the stress fields induced by indentation. In present article, a new method to determine the stress intensity factors of the indentation problems is developed based on the conservation law. The physical meanings of the proposed method and some numerical analysis have been investigated.
Wu, Y.,Chen, Z.,Meng, Z.,Hu, L.,Gonzalez de Vicente, S.M.,Merrill, B.,Panayotov, D.,Zucchetti, M.,Kolbasov, B.,van Houtte, D.,Bustreo, C.,Kim, Y.,Sakamoto, Y.,Kim, K.,Maisonnier, D.,Clark, D.,Kalashni International Atomic Energy Agency 2018 Nuclear fusion Vol.58 No.9
<P>The 2nd International Workshop on Environmental, Safety and Economic Aspects of Fusion Power (ESEFP) was held on 23 September 2017 in Kyoto, Japan. The workshop was initiated by the International Energy Agency Technology Collaboration Program on ESEFP. The workshop was well attended with approximately forty participants representing fifteen institutions in eight countries. The presentations covered safety issues and environmental impacts, availability improvement and risk control and socio-economic aspects of fusion power. Quantitative safety assessment of fusion reactors was discussed in depth with the consensus output presented as a plenary presentation at the 13th International Symposium on Fusion Nuclear Technology (ISFNT-13). The next workshop is planned to be held in conjunction with the ISFNT-14 in 2019.</P>