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611.
姚万勤 《孝感职业技术学院学报》2011,(3):78-82
犯罪构成理论是犯罪论的中心课题,是认定某行为是否成立犯罪的核心环节。但是我国的犯罪构成相较于德日三阶层的犯罪论存在与犯罪概念界定不清,正当化事由在体系中的地位不明,缺乏阶层性,易导致主观归罪,期待可能性地位缺失等诸多不合理之处。有必要对我国的传统犯罪构成理论的缺陷进行深入剖析,以有助于我国犯罪构成体系的完善。 相似文献
612.
The experimental performance of small-sized ground-coupled heat pump (GCHP) is researched intensively. However, there are little data documenting the operation performance of existing large-sized GCHP system. We presented the actual performance measurement of a GCHP installed for apartment buildings in Wuhan, Hubei province, P. R. China. The system was constructed with a closed vertical typed ground heat exchanger with a total pipe length of 32 000 m. During one year, various operating parameters were monitored, including the outdoor temperature, the flow rate, the electrical consumption, and the water temperature. The seasonal coefficients of performances of the heat pumps and the system based on the measured data were found to be 4.01 and 2.96 in the cooling season, and 3.54 and 2.86 in the heating season, respectively. The GCHP system was more economical than the air-source room air conditioner in the energy efficiency which was increased by 29 in cooling mode and 50 in heating mode. There was an obvious heat imbalance of soil between the injection rate and the extraction rate in the residential GCHP system operation. 相似文献
613.
以浙江某高速公路路基工程为例,介绍高压旋喷注浆法加固软土地基的原理、施工工艺、施工方法、质量检测内容及质量控制措施,对处理后的软土地基进行详细的喷射固结质量检测,并列出质量检测的内容。 相似文献
614.
孟庆生 《中国教育技术装备》2003,(2):36-38,40
介绍了目前学校修建塑胶体育场过程中存在的问题,对发生这些问题的原因进行了探讨,还对修建塑胶体育场的设计图纸进行了较详细的说明。 相似文献
615.
王健凡 《福建工程学院学报》2005,3(4):389-391
通过某一工程载荷试验和施工后的沉降观察证明,采用小断面静压预制桩作为高层或小高层建筑复合地基的加固体,对施工条件受周边建筑物限制的岩溶地区进行处理,具有对周边影响小、工效高、桩身质量可靠和承载力有保证等优点。 相似文献
616.
大学生思想政治教育过程方法论探微 总被引:1,自引:0,他引:1
杨艳茹 《辽宁师范大学学报(社会科学版)》2004,27(3):66-68
教育过程中的方法论.是思想政治教育方法论系统研究的关键,是思想政治教育实效性研究的关键。教育的自我定位是人生导师、朋友.还是家长?这是教育过程方法论研究的首要问题和观念问题。 相似文献
617.
Electromyographic (EMG) activity of the leg muscles and the ground reaction forces were recorded in 17 elite male middle-distance runners, who performed isometric maximal voluntary contractions (MVC) as well as running at different speeds. Electromyograms were recorded from the gluteus maximus, vastus lateralis, biceps femoris, gastrocnemius and tibialis anterior. The results indicated that the averaged EMG (aEMG) activities of all the muscles studied increased (P?<?0.05) with increasing running speed, especially in the pre-contact and braking phases. At higher speeds, the aEMG activities of the gastrocnemius, vastus lateralis, biceps femoris and gluteus maximus exceeded 100% MVC in these same phases. These results suggest that maximal voluntary contractions cannot be used as an indicator of the full activation potential of human skeletal muscle. Furthermore, the present results suggest that increased pre-contact EMG potentiates the functional role of stretch reflexes, which subsequently increases tendomuscular stiffness and enhances force production in the braking and/or propulsive phases in running. Furthermore, a more powerful force production in the optimal direction for increasing running speed effectively requires increased EMG activity of the two-joint muscles (biceps femoris, rectus femoris and gastrocnemius) during the entire running cycle. 相似文献
618.
Nathan W. Saunders Nicholas Hanson Panos Koutakis Ajit M. Chaudhari 《Journal of sports sciences》2013,31(11):1042-1049
AbstractResearchers and clinicians have suggested that overuse injuries to the lower back and lower extremities of figure skaters may be associated with the repeated high impact forces sustained during jump landings. Our primary aim was to compare the vertical ground reaction forces (GRFs) in freestyle figure skaters (n = 26) and non-skaters (n = 18) for the same barefoot single leg landing on a force plate from a 20 cm platform. Compared with non-skaters, skaters exhibited a significantly greater normalised peak GRF (3.50 ± 0.47 × body weight for skaters vs. 3.13 ± 0.45 × body weight for non-skaters), significantly shorter time to peak GRF (81.21 ± 14.01 ms for skaters vs. 93.81 ± 16.49 ms for non-skaters), and significantly longer time to stabilisation (TTS) of the GRF (2.38 ± 0.07 s for skaters vs. 2.22 ± 0.07 s for non-skaters). Skaters also confined their centre of pressure (CoP) to a significantly smaller mediolateral (M–L) (25%) and anterior–posterior (A–P) (40%) range during the landing phase, with the position of the CoP located in the mid to forefoot region. The narrower and more forward position of the CoP in skaters may at least partially explain the greater peak GRF, shorter time to peak, and longer TTS. Training and/or equipment modification serve as potential targets to decrease peak GRF by distributing it over a longer time period. More comprehensive studies including electromyography and motion capture are needed to fully characterise the unique figure skater landing strategy. 相似文献
619.
Abstract Dynamic postural stability has been widely studied for single-leg landing, but seldom considered for double-leg landing. This study aimed to evaluate the dynamic postural stability and the influence mechanism of muscle activities during double-leg drop landing. Eight recreationally active males and eight recreationally active females participated in this study and dropped individually from three heights (0.32?m, 0.52?m, and 0.72?m). Ground reaction force was recorded to calculate the time to stabilisation. Electromyographic activities were recorded for selected lower-extremity muscles. A multivariate analysis of variance was carried out and no significant influence was found in time to stabilisation between genders or limb laterals (P?>?0.05). With increasing drop height, time to stabilisation decreased significantly in two horizontal directions and the lower-extremity muscle activities were enhanced. Vertical time to stabilisation was not significantly influenced by drop height. Dynamic postural stability improved by neuromuscular change more than that required due to the increase of drop height. Double-leg landing on level ground is a stable movement, and the body would often be injured before dynamic postural stability is impaired. It is understandable to protect tissues from mechanical injuries by the sacrifice of certain dynamic postural stability in the design of protective devices or athlete training. 相似文献
620.
Claudia Knoepfli-Lenzin Jennifer Carole Waech Turgut Gülay Florian Schellenberg Silvio Lorenzetti 《Journal of sports sciences》2013,31(18):1671-1679
AbstractRunning shoe construction influences the forces experienced by the human body while running. The aim of this study was to ascertain whether the new sole architecture of the On running shoe reduces ground reaction forces compared with running barefoot or with a conventional running shoe and whether it changes the physiological parameters of running in shoes. Thirty-seven trained male participants were studied while running at submaximal speeds wearing their conventional running shoe, wearing the On running shoe and while barefoot. Additional biomechanical and physiological values were investigated to determine whether the On running shoe induced any changes in these parameters compared with conventional running shoes. The On exhibited similar ground reaction forces as conventional shoes, and these were different from the forces experienced while running barefoot, showing that the On was more similar to typical shoed running. No difference was observed in running economy between the On and a conventional shoe model. However, a slightly lower heart rate (HR) (≈1.3%) and blood lactate concentration (≈5.5%) were observed during submaximal running with the On running shoe compared with a conventional running shoe, as well as a greater lateral deviation of the centre of pressure mid-stance. The ramifications of the reduced HR and blood lactate concentration for competitive performance are unknown. 相似文献