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排序方式: 共有33条查询结果,搜索用时 203 毫秒
1.
根据产品跳转的时机、方式以及后果,制药企业产品跳转行为或属于产品创新,或表现为产品垄断。我国与西方国家在规制制药企业产品跳转行为的路径上存在着优先顺序上的差异。在国家促进仿制药市场健康发展的背景下,我国规制制药企业产品跳转行为的合理路径应是优先适用专利法,严格遵守专利授予标准,并推进专利法与反垄断法、药品管理制度等法律规范的和谐共生。  相似文献   
2.
提出了适合无中心控制的对等网络的盲空时自适应干扰消除算法.本算法利用检测信号功率恒定的特点,采用了两个滤波器组,当其中一个工作时,另一个开始调整权系数,从而提高了收敛速度,避免了跳频频率变化带来的波束估计误差.仿真结果表明,提出的盲自适应算法可以明显提高输出信号SINR增益.  相似文献   
3.
We prepared conducting polyaniline (PAn) co-doped with sulfosalicylic acid (SSA) and dodecylbenzoyl sultonic acid (DBSA) in micro-emulsive polymerization, and studied its charge transport behaviors based on the measurement of its electrical conductivity in the temperature range between 203 K and 298 K. The conductivity was found to increase with temperature, similar to the case in semiconductors. Analyzing the experimental data with three models, namely the charge-energy-limitedtunneling model, Kivelson model and the three-dimensional variable range hopping (3D-VRH) model demonstrated that these models all describe well the charge transport behaviors of PAn co-doped with SSA and DBSA within the mentioned temperature range. From calculation with the 3D-VRH model, the hopping distance of the conducting PAn is obviously larger than its localization length. The PAn doped with SSA and DBSA enjoys desirable crystallinity due to the co-doping of two functional sulfonic acids. The macroscopic conductivity may correspond to three-dimensional transport in the network of the bundles, and the metallic islands may be attributed to quasi-one-dimensional bundles.  相似文献   
4.
介绍一种加密和解密技术———滚动码技术,并在对滚动码技术优点进行分析的基础上,利用HCS301滚动码编码器和PIC16C54单片机开发了一种可靠性和安全性较高的车库智能防盗系统.  相似文献   
5.
FFH/MFSK系统抗干扰性能研究   总被引:1,自引:0,他引:1  
针对FFH/MFSK通信系统的特点,推导了在赖斯衰落信道下,多音干扰产生的虚警检测概率和漏检概率数学表达式,并研究了不同参数对系统BER性能的影响. 仿真结果表明,在多音干扰功率大于一定值时,多音干扰数量是造成系统BER性能下降的主要因素.  相似文献   
6.
白娟 《天津电大学报》2003,7(2):31-32,35
在无线通讯领域,蓝牙技术引起了越来越多的人的关注。本文介绍了蓝牙技术的起源及工作原理。阐述了它在实际生活中的应用。并对蓝牙技术的进一步发展提出展望。  相似文献   
7.
Abstract

The aim of the study was to assess the reliability of a mobile contact mat in measuring a range of stretch–shortening cycle parameters in young adolescents. Additionally, vertical leg stiffness using contact mat data was validated against a criterion method using force–time data. The reliability study involved 18 youths completing a habituation and three separate test sessions, while 20 youths completed a single test session for the validity study. Participants completed three trials of a squat jump, countermovement jump, and maximal hopping test and a single trial of repeated sub-maximal hopping at 2.0 Hz and 2.5 Hz. All tests were performed on the contact mat. Reliability statistics included repeated-measures analysis of variance, intraclass correlation coefficient, and coefficient of variation (CV), while the correlation coefficient (r) and typical error of estimate (TEE) were reported for the validity study. Squat jump height was the most reliable measure (CV = 8.64%), while leg stiffness during sub-maximal hopping, and reactive strength index produced moderate reliability (CV = 10.17–13.93% and 13.98% respectively). Measures of leg stiffness obtained from contact mat data during sub-maximal hopping were in agreement with the criterion measure (r = 0.92–0.95; TEE = 6.5–7.5%), but not during maximal hopping (r = 0.59; TEE = 41.9%). The contact mat was deemed a valid tool for measuring stretch–shortening cycle ability in sub-maximal but not maximal hopping. Although reliability of performance was generally moderate, the tests offer a replicable assessment method for use with paediatric populations.  相似文献   
8.
The associations among lower extremity functional performance and quality of life in obese youth are unknown. The aims of this study were to compare lower extremity strength, lower extremity functional performance, and health related quality of life between obese and healthy-weight youth and evaluate the relationships between lower extremity performance and health related quality of life in obese youth. Twenty obese and 20 age and sex matched healthy-weight youth were recruited. Peak torque of the major lower extremity muscles were measured. Functional performance was measured with single leg hop and single leg balance tests. The Paediatric Quality of Life questionnaire's physical and psychosocial health subscales were used. Paired t-tests and multiple regression analyses were performed. Obese youth demonstrated decreased peak torque in all muscles measured (P < 0.05), poorer functional performance (P < 0.05), and worse physical health related quality of life (P < 0.05) compared to healthy-weight youth. Lower extremity functional performance was associated with aspects of quality of life in the obese group (P = 0.002), but not in the healthy-weight group (P < 0.05). These results may assist in encouraging best practices in the promotion of exercise, physical activity, and quality of life in obese youth.  相似文献   
9.
产品跳跃常常被视为原研药企阻击竞争对手仿制药企的一种战略, 从而受到反垄断的审查和规制。然而,排除那些存在制造隐患、恶意诋毁或创新骗局外,更多的产品跳跃是一种创新活动,对其严苛监管将很大程度上抑制整个行业的发展,并最终传导到消费者,降低全社会福祉。  相似文献   
10.
随着科学技术的进步,各类无线数据通信设备的不断推出,无线数据通信事业的发展取得长足进展,同时无线电频率资源却日益紧张,通信干扰现象也较为严重,造成传输速率低下、可靠性降低;迫切需要一种新的技术手段加以解决;通过介绍扩频通信的基本原理、技术特点、实现方案、和在现代高速数据通信中的广泛应用,揭示了扩频技术在解决常规数据通信传输速率低下和频谱利用不合理等方面,起到的主要作用,阐述了扩频技术的广泛应用在无线电频谱资源管理工作中的重大意义和通信技术的优良性能和广阔的发展前景。  相似文献   
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