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10个宜机收夏玉米品种茎秆抗倒特性比较 被引量:3
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作者 李中建 许洛 +1 位作者 郑书海 冯健英 《河北农业科学》 2019年第5期28-32,共5页
为筛选适宜河北省机械收获的夏玉米品种,搜集近几年通过审定和待审的适宜机械化收获子粒的夏玉米新品种或新组合10个,以目前河北省夏播区推广面积较大且抗倒性较为突出的郑单958和先玉335为对照,利用茎秆强度测定仪对其抽雄期、灌浆期... 为筛选适宜河北省机械收获的夏玉米品种,搜集近几年通过审定和待审的适宜机械化收获子粒的夏玉米新品种或新组合10个,以目前河北省夏播区推广面积较大且抗倒性较为突出的郑单958和先玉335为对照,利用茎秆强度测定仪对其抽雄期、灌浆期、蜡熟期的茎节穿刺强度和压弯力度进行测定,并比较了指标的差异性。结果表明:联创808、迪卡517、同德139、万盛106、德美亚3号、衡玉1702、先玉047和舍玉D101为抗倒性较强品种,其中万盛106、衡玉1702、先玉047和德美亚3号的抗倒性更加突出。研究结果为筛选出适合河北省中南部推广种植的适宜机械化收获子粒的夏玉米新品种提供了理论依据。 展开更多
关键词 宜机收品种 夏玉米 抗倒性 茎秆 穿刺强度 压弯力度 品种比较
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Effects of bending on heat transfer performance of axial micro-grooved heat pipe 被引量:5
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作者 蒋乐伦 汤勇 潘敏强 《Journal of Central South University》 SCIE EI CAS 2011年第2期580-586,共7页
Heat pipe is always bent in the typical application of electronic heat dissipation at high heat flux,which greatly affects its heat transfer performance. The capillary limit of heat transport in the bent micro-grooved... Heat pipe is always bent in the typical application of electronic heat dissipation at high heat flux,which greatly affects its heat transfer performance. The capillary limit of heat transport in the bent micro-grooved heat pipes was analyzed in the vapor pressure drop,the liquid pressure drop and the interaction of the vapor with wick fluid. The bent heat pipes were fabricated and tested from the bending angle,the bending position and the bending radius. The results show that temperature difference and thermal resistance increase while the heat transfer capacity of the heat pipe decreases,with the increase of the bending angles and the bending position closer to the vapor section. However,the effects of bending radius can be ignored. The result agrees well with the predicted equations. 展开更多
关键词 electronics cooling system axial micro-grooved heat pipe BENDING heat transfer performance
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Analysis and Improvement of Standing-Up Action for Elderly People from a Chair Using a Cushion-Type Support Tool
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作者 Masakazu Takahashi Reiji Nanba 《Computer Technology and Application》 2012年第11期713-722,共10页
This paper reports the problems that elderly people have when they stand up from a chair, and proposes an adequate standing-up procedure that solves these problems. The important points for an adequate standing-up pro... This paper reports the problems that elderly people have when they stand up from a chair, and proposes an adequate standing-up procedure that solves these problems. The important points for an adequate standing-up procedure are "leaning the upper body forward" and "pulling the legs to the side". Furthermore, this paper proposes a standing-up support tool. The characteristics of the support tool are a cushion-type shape with an adjustable flange and an air-pressure-driven mechanism. When the proposed standing-up procedure and support tool are applied to elderly people, the measured values related to standing-up, such as maximum acceleration, arm force, standing-up time, heel position and forward-bending angle, are improved. Furthermore, elderly people felt that it made the standing-up action easy. We could confirm the effectiveness of the proposed standing-up procedure and support tool. 展开更多
关键词 Elderly people standing-up procedure standing-up support tool cushion-type shape air-pressure-driven mechanism.
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A new adaptive bending method using closed loop feedback control 被引量:3
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作者 T.WELO B.GRANLY 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第11期2111-2117,共7页
As the competition from companies in low cost countries increases,the need for more automated production which reduces labour cost while improving product quality is required.A new rotary compression bending set-up wi... As the competition from companies in low cost countries increases,the need for more automated production which reduces labour cost while improving product quality is required.A new rotary compression bending set-up with automated closed-loop feedback control is thus being developed.By transferring in-process measurement data into an algorithm for predicting springback and bend angle prior to the unloading sequence,the dimensional accuracy is improved.This work focuses on the development of this steering model.Since the method used does not increase cycle time,it is attractive for high-volume industrial applications.More than 150 bending tests of AA6060 extrusions were conducted to determine the capability of the technology.The results show that by activating the automated closed-loop feedback system,the dimensional accuracy of the bent parts is more than three times better than that obtained by traditional compression bending.Since the steering model permits the direct use of additional process data,such as instant wall thickness and cross sectional distortions,it is believed that extension of the measurement capabilities would improve the accuracy of the methodology even further. 展开更多
关键词 adaptive bending closed-loop feedback dimensional accuracy SPRINGBACK aluminium EXTRUSION
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Pressure Wave and Fluid Velocity in a Bend-Mode Inkjet Nozzle with Double PZT Actuators 被引量:3
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作者 Sungu Kim Jaeyong Sung Myeong Ho Lee 《Journal of Thermal Science》 SCIE EI CAS CSCD 2013年第1期29-35,共7页
A new concept of bend-mode inkjet nozzle with double PZT (lead zirconate titanate) actuators has been designed and fabricated in the present study. Then the pressure wave and fluid velocity at the nozzle exit have bee... A new concept of bend-mode inkjet nozzle with double PZT (lead zirconate titanate) actuators has been designed and fabricated in the present study. Then the pressure wave and fluid velocity at the nozzle exit have been investigated. The complex pressure behavior inside the channel was solved numerically based on the narrow channel acoustic theory. The two PZTs attached to a rectangular channel were actuated sequentially by setting the waveforms of each PZT to be center-aligned with various pulse widths. As a result, the double PZT actuation is superior to the single PZT actuation in view of strong momentum force and fast dissipation of residual pressure. The maximum fluid velocity at the nozzle exit is observed when the respective pulse widths equal to their optimum pulse widths. The numerical results are supported by the experimental results with the fabricated inkjet device by measuring the speed of meniscus just out of the nozzle. 展开更多
关键词 double PZT actuators inkjet nozzle narrow channel theory pressure wave sequential actuation
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Supersonic Cavity Flows over Concave and Convex Walls
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作者 A Ran Ye Rajarshi Das +1 位作者 Toshiaki Setoguchi Heuy Dong Kim 《Journal of Thermal Science》 SCIE EI CAS CSCD 2016年第2期145-152,共8页
Supersonic cavity flows are characterized by compression and expansion waves, shear layer, and oscillations inside the cavity. For decades, investigations into cavity flows have been conducted, mostly with flows at ze... Supersonic cavity flows are characterized by compression and expansion waves, shear layer, and oscillations inside the cavity. For decades, investigations into cavity flows have been conducted, mostly with flows at zero pressure gradient entering the cavity in straight walls. Since cavity flows on curved walls exert centrifugal force, the features of these flows are likely to differ from those of straight wall flows. The aim of the present work is to study the flow physics of a cavity that is cut out on a curved wall. Steady and unsteady numerical simulations were carried out for supersonic flow through curved channels over the cavity with L/H = 1. A straight channel flow was also analyzed which serves as the base model. The velocity gradient along the width of the channel was observed to increase with increasing the channel curvature for both concave and convex channels. The pressure on the cavity floor increases with the increase in channel curvature for concave channels and decreases for convex channels. Moreover, unsteady flow characteristics are more dependent on channel curvature under supersonic free stream conditions. 展开更多
关键词 Cavity flow Supersonic Flow Compressible Flow Unsteady flow Pressure Oscillation
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