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1.
This article describes designing, implementation and tuning processes of multiple-tapped-delay-line (MTDL). Obtained MTDL can be implemented in various field-programmable-logic-devices (FPGA) devices and applied for time-to-digital-converters (TDC) construction. The task of tuning process is the tapped-delay-line (TDL) linearisation, and consists of two stages. The first stage depends on selecting an appropriate configurable-logic-block (CLB) for particular delay-segment realization and selecting proper connection between these blocks. The second tuning stage, that is essential from this article viewpoint, depends on inter CLBs connecting wires delay regulation realized directly by load regulation. The Load regulation depends on connecting an appropriate number of unused three-state-buffers or CLB inputs to the wire which delay is adjusted. Depending on the number of inputs connected to the wire its capacitance changes that influences its time-constant and finally changes its time-delay.The MTDL mathematical model, obtained characteristics and results of time-interval (TI) measurements are also presented. The derived TDL model provides information about how the particular wire delay should be changed and in which order the changes should be executed. This makes the designing process predictable and easy to carry out. Presented characteristics confirm the proper operation of presented linearisation technique. The proper operation of the whole measuring module is confirmed by obtained TIs histograms presentation.  相似文献   
2.
Measurement of liking with consumers is often performed on a single sip or mouthful of the product and results in a single liking score that does not necessarily reflect the liking over consumption of a whole product. A dynamic approach could provide this type of information. Thus, obtaining reasons why the liking score is changing over consumption could help to gain insights for product improvement. Recently, Thomas, Visalli, Cordelle, and Schlich (2015) suggested collecting with the same consumers liking scores dynamically and Temporal Dominance of Sensations (TDS) during mono-intakes of flavored cheeses, in two independent sessions. This new type of sensory data has been analysed at individual level to identify “temporal drivers of liking” for each product.The present paper further develops this method consisting of collecting TDS and dynamic liking data in the same session and during the consumption of the full portion of a product. The products used to experiment this new method were two commercial oral nutritional supplements (ONS) assessed by 65 consumers over two lab sessions separated by one week.The protocol consisted of a TDS evaluation of 5 flavor, 2 texture and 3 taste sensations during each sip, immediately followed by a liking scale. This protocol was repeated over sips. This method, named “Alternated Temporal Drivers of Liking” (A-TDL), required that consumers record liking changes and do TDS over sips during food consumption. Results showed that one of the two ONS was more liked than the other and consumed in a larger volume resulting in a higher energy intake. In contrast, the other product resulted in a stronger thirst and presented more negative temporal drivers of liking (dry, metallic, filming) over the consecutive sips.  相似文献   
3.
在数据链系统的生命周期中,仿真是不可缺少的一个环节。针对商用软件成本高,教育版无源代码难以二次开发问题,采用新型开源网络仿真软件OMNeT^++,利用Mobility Framework组件构架,编写了轮询协议模型,建立了数据链仿真系统模型和Link 11网络模型,通过场景和统计模块的设计,对Link 11进行了性能仿真实验。仿真结果表明,网络性能良好,基本满足了消息传输的实时性和可靠性。  相似文献   
4.
In this paper, the performance of uncoded uplink transmissions in a broadband code division multiple access (CDMA) system using tapped delay line (TDL) antenna array under multipath conditions is investigated. An expression for broadband CDMA system is derived to calculate the optimal weights of TDL antenna array. Using the derived broadband expression, the performance of TDL antenna array is investigated and compared with that of the already existing narrowband systems. Simulation results show that TDL antenna array can reduce multipath fading and multiple access interference (MAI). It is shown that if the signal‐to‐noise ratio (SNR) level is maintained at 20 dB and two‐ray channel model is used, two antennas with four taps each can support 30 users with a BER of 10?3. If three‐ray channel model is used, the same antenna arrangement is not enough to support 30 users. To support these 30 users with BER of 10?3, the number of taps needs to be increased to eight. Finally, the number of taps needs to be further increased to 16 if four‐ray channel model is used. Not only that, the SNR should also be increased to 25 dB to achieve the same BER. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
5.
战术数据链(TDL)的作用就是在战场上能够更准确、有效和快速地传递战术情报。随着军事信息技术的发展,战场上的节点数量和传输数据呈现快速增长趋势。传统的战术数据链媒介访问控制(MAC)协议为了保证QoS,一般采用固定资源分配的多址访问算法,如TDMA,在面对大容量、高速率的需求时缺乏灵活性和有效性。为此,研究了基于统计优先级多址访问(SPMA)算法,提出了直接映射和差分趋势两种动态门限方法。仿真结果表明,动态门限比固定门限能够有效提高系统效率,更接近目标信道忙闲比设计,并且在相同负载下网络吞吐量也较固定门限高。  相似文献   
6.
7.
运动估计算法分析   总被引:7,自引:1,他引:6  
对常用的运动补偿图像算法(如全搜索法、三步法、共轭方向搜索法、两维对数下降法等)从各个方面进行了比较,最终选出最快、最准确的算法-两步搜索法。  相似文献   
8.
主要通过GGE到本模、TDS(TD-SCDMA)模、TDL(TD-LTE)模的重定向过程,来进一步探讨GGE与LTE多模终端之间的重定向关系。结合多模终端重定向过程中的协议栈的流程进行了设计和实现,通过规范化和描述语言(SDL)和树表结合法(TTCN)进行了仿真测试产生MSC图,验证了信令流程的正确性。  相似文献   
9.
依据雷州半岛东岸的东寮岛滨海地下水测井潮周期取样测试数据,以Cl-为保守离子,应用海水稀释方法,探讨了在海水入侵过程中Ca2+的迁移性。结果显示,Ca2+含量随海水进退呈现波动势态,含量很高,远高于背景值和雷州半岛东岸其它测井,也明显高于海水中的含量;Ca2+表现出明显的非保守性和迁移性,实际数据点位于理论稀释线TDL的上方,存在明显的阳离子交换现象;Δ表示测井实测值与理论值的差异,可体现出海水入侵过程中孔隙介质对离子的吸附和释出。ΔCa2+平均为527.26~574.85mg/L,ΔNa+、ΔMg2+、ΔK+均0,ΔCa2+与这三者逐时变化存在着反相特征,ΔNa++ΔMg2++ΔK+绝对值很高为阳离子充分置换提供了基础,ΔNa+当量比例超过50%,三种阳离子共同参与对Ca2+的置换,但以Na+为主;ΔCa2+时间变化趋势为基本不变,线性或者对数缓慢单增;Ca2+的阳离子置换促使Na+滞留于孔隙介质,降低了测井地下水的总溶解性盐类含量,但同时大量钙离子的迁出又使得测井地下水硬度增高。  相似文献   
10.
战术数据链系统中,平台的差异性以及消息自身的特点导致了平台对网络资源需求的不均匀性。为了满足繁重网络业务量产生的特殊传输需求,设计了一种战术消息流量管理器(TM)。首先给出其设计原理,接着介绍系统建模,最后给出了TM的仿真性能结果及其分析。  相似文献   
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