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Effects of Different Facilities on Laying Performance,Egg Quality and Air Quality for Layers Under Free Range System 被引量:1
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作者 GENG Ai-lian WANG Liang +2 位作者 ZHOU Yong-xiao ZENG Min LIU Hui 《Animal Husbandry and Feed Science》 CAS 2013年第2期87-91,共5页
[ Objective] This paper aimed to study the effects of different facilities on laying performance, egg quality and air quality for commercial layers under free range system. [Metbod] The single factorial arrangement wa... [ Objective] This paper aimed to study the effects of different facilities on laying performance, egg quality and air quality for commercial layers under free range system. [Metbod] The single factorial arrangement was used in the tdal. 2 800 commercial Beijing You Chicken (BYC) at 23 weeks of age were chosen and randomly divided into four groups, three replicates each group, and 210 birds each replicate. The layers lived in loose housing condition with deep litter inside. Group 1 was the control, equipped with standard laying boxes, and flat-type perches; group 2 was e- quipped with common laying boxes, and flat-type perches; group 3 was equipped with common laying boxes, and erect-type perches, and group 4 was equipped with standard laying boxes, and erect-type perches. The laying performance, laying position and egg quality of birds during 24 to 32 weeks of age were recorded and measured, and average NH3, CO~ concentration of each group at 32 weeks of age were measured and detected. [Result] The results showed that laying performance of commercial BYC under loose housing condition were significantly different during 24 -32 weeks of age. The laying rate of the control group equipped with flat-type porches and standard laying boxes (33.25%) was significantly higher than in group equipped with flat-type perches and common laying boxes (21.83%) (P〈0.05), and other two groups (26.04% and 27.48%) (P 〈0.05). The ratio of floor eggs was significantly lower in groups with standard laying boxes than in the groups with common laying boxes (P 〈0. 05), and the laying proportion in the first floor of layer boxes were much higher than those in the second floor ( P 〈 0.05). There were no significant differences on egg quality among the groups (P〉0.05). Average NH3, CO2 concentration of group 3 and 4 at 82 weeks of age were both signifi- cantly higher than of group 1 and 2 (P 〈0.05). [ Conclusion] All of the above indicated that the utilization of facilities could improve layer's laying rate, especially with flat-type perches and standard laying boxes, and the indoor air quality was also affected to some extent. 展开更多
关键词 free range system Facilities Laying performance Egg quality Air quality
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无线传感器网络Range-free自身定位算法仿真分析 被引量:16
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作者 衣晓 刘瑜 黄越平 《海军航空工程学院学报》 2009年第4期369-375,共7页
定位技术是无线传感器网络重要的支撑技术之一。文章在总结有关定位算法的文献和研究成果的基础上。介绍了6种代表性的Range-free定位算法的原理,在Matlab环境下构造了网络拓扑场景进行了仿真实验,对6种代表性算法的性能进行比较并分... 定位技术是无线传感器网络重要的支撑技术之一。文章在总结有关定位算法的文献和研究成果的基础上。介绍了6种代表性的Range-free定位算法的原理,在Matlab环境下构造了网络拓扑场景进行了仿真实验,对6种代表性算法的性能进行比较并分析总结,指出了今后无线传感器网络定位算法的研究中所需解决的问题。 展开更多
关键词 无线传感器网络 rangefree 自身定位 定位算法
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基于Range-free的WSN定位技术研究
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作者 吴文平 潘正高 张晓梅 《贵阳学院学报(自然科学版)》 2017年第2期35-37,共3页
通过对无线传感器网络WSN中的非测距定位(Range-free)技术进行分析,阐述非测距定位技术的基本思想,并对一些经典的非测距定位技术进行研究与比较。首先,阐述WSN中非测距定位技术的主要思想;其次,分析和比较一些典型的非测距定位技术;最... 通过对无线传感器网络WSN中的非测距定位(Range-free)技术进行分析,阐述非测距定位技术的基本思想,并对一些经典的非测距定位技术进行研究与比较。首先,阐述WSN中非测距定位技术的主要思想;其次,分析和比较一些典型的非测距定位技术;最后,分析非测距定位技术的研究现状与发展趋势。 展开更多
关键词 WSN rangefree 定位技术
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无线传感器网络Range-free节点定位算法研究
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作者 张清国 谢松 《现代计算机》 2013年第16期3-9,18,共8页
作为一种全新的信息获取和处理技术,无线传感器网络在现代社会中起着越来越大的作用,其中网络节点的自身定位是应用的前提条件。综合分析大量无线传感器网络节点定位算法相关文献,详细说明一些常见无线传感器网络range-free自身定位算... 作为一种全新的信息获取和处理技术,无线传感器网络在现代社会中起着越来越大的作用,其中网络节点的自身定位是应用的前提条件。综合分析大量无线传感器网络节点定位算法相关文献,详细说明一些常见无线传感器网络range-free自身定位算法并对其中一些改进算法进行介绍。通过对这些算法进行比较,指出未来的研究方向。 展开更多
关键词 无线传感器网络 rangefree 节点定位
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A Highly Compact Third-Order Silicon Elliptical Micro-Ring Add-Drop Filter with a Large Free Spectral Range 被引量:1
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作者 关欢 李智勇 +2 位作者 沈海华 王睿 俞育德 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期61-63,共3页
We demonstrate a highly compact third-order elliptical micro-ring add-drop filter based on a silicon-on-insulator wafer. The elliptical micro-ring resonator has a major radius of 6μm (minor radius of 4.112μm) and ... We demonstrate a highly compact third-order elliptical micro-ring add-drop filter based on a silicon-on-insulator wafer. The elliptical micro-ring resonator has a major radius of 6μm (minor radius of 4.112μm) and a large free spectral range of 18 nm. Experimental results show a box-like channel dropping response, which has a 3 dB bandwidth of -2.7nm, high out-of-band signal rejection of around 40dB and a very low drop loss (〈0.5dB). Simulation agrees well with the experiments. The footprint of the whole chip is only 0.0003mm2. 展开更多
关键词 FSR A Highly Compact Third-Order Silicon Elliptical Micro-Ring Add-Drop Filter with a Large free Spectral range
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Distortion-Free Data Embedding Scheme for High Dynamic Range Images
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作者 Chin-Chen Chang Thai-Son Nguyen Chia-Chen Lin 《Journal of Electronic Science and Technology》 CAS 2013年第1期20-26,共7页
Distortion-free data embedding is a technique which can assure that not only the secret data is correctly extracted but also the cover media is recovered without any distortion after secret data is extracted completel... Distortion-free data embedding is a technique which can assure that not only the secret data is correctly extracted but also the cover media is recovered without any distortion after secret data is extracted completely. Because of these advantages, this technique attracts the attention of many researchers. In this paper, a new distortion-free data embedding scheme for high dynamic range (HDR) images is proposed. By depending on Cartesian product, this scheme can obtain higher embedding capacity while maintaining the exactly identical cover image and stego image when using the tone mapping algorithms. In experimental results, the proposed scheme is superior to Yu et aL's scheme in regard to the embedding rate——an average embedding rate of 0.1355 bpp compared with Yn et aL's scheme (0.1270 bpp). 展开更多
关键词 Data hiding distortion free high dynamic range image high embedding rate stegano-graphy.
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Dynamic Free-Spectral-Range Measurement for Fiber Resonator Based on Digital-Heterodyne Optical Phase-Locked Loop
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作者 Hongchen Jiao Tao Wang +2 位作者 Heli Gao Lishuang Feng Honghao Ma 《Optics and Photonics Journal》 2021年第8期332-340,共9页
<div style="text-align:justify;"> We propose a novel scheme, based on digital-heterodyne optical phase-locked loop with whole-fiber circuit, to dynamically measure the free-spectral-range of a fiber re... <div style="text-align:justify;"> We propose a novel scheme, based on digital-heterodyne optical phase-locked loop with whole-fiber circuit, to dynamically measure the free-spectral-range of a fiber resonator. The optical phase-locked loop is established with a differential frequency-modulation module consists of a pair of acousto-optic modulators. The resonance-tracking loop is derived with the Pound-Drever-Hall technique for locking the heterodyne frequency of the OPLL on the frequency difference between adjacent resonance modes. A stable locking accuracy of about 7 × 10<sup>?9</sup> and a dynamic locking accuracy of about 5 × 10<sup>?8</sup> are achieved with the FSR of 8.155 MHz, indicating a bias stability of the resonator fiber optic gyro of about 0.1?/h with 10 Hz bandwidth. In addition, the thermal drift coefficient of the FSR is measured as 0.1 Hz/?C. This shows remarkable potential for realizing advanced optical measurement systems, such as the resonant fiber optic gyro, and so on. </div> 展开更多
关键词 free Spectral range Fiber Resonator Dynamic Measurement Digital-Heterodyne Optical Phase-Locked Loop Resonant Fiber Optic Gyro
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无线传感器网络一种改进的convex定位算法 被引量:3
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作者 范磊 刘锋 《无线电通信技术》 2007年第1期52-55,共4页
以convex(凸规划)定位算法为基础,针对range-free定位算法中anchor(已知节点)比例低带来的定位精度低、网络覆盖率低的问题,提出了二跳信息改进定位算法。该算法中,未知节点在通信中加入自身邻居anchor的ID和位置信息并发送给邻居节点,... 以convex(凸规划)定位算法为基础,针对range-free定位算法中anchor(已知节点)比例低带来的定位精度低、网络覆盖率低的问题,提出了二跳信息改进定位算法。该算法中,未知节点在通信中加入自身邻居anchor的ID和位置信息并发送给邻居节点,相应的邻居节点从中确定自己的二跳邻居anchor,并利用二跳邻居anchor的二跳通信范围来减小未知节点的可能存在区域,进而提高未知节点的定位精度。仿真表明,二跳信息改进定位算法在anchor节点比例较低情况下能有效提高定位精度,而在anchor节点比例较高时接近原convex算法定位精度,并且网络规模越大这种提高越显著。 展开更多
关键词 rangefree定位算法 无线传感器网络 CONVEX
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Impact of cavity symmetry on mode suppression and increase of free spectral range in solid-state dye microlaser
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作者 Sergei Popov Sebastien Ricciardi +1 位作者 Ari T.Friberg Sergey Sergeyev 《Chinese Optics Letters》 SCIE EI CAS CSCD 2007年第11期651-653,共3页
We describe modeling the solid-state dye laser with the microcavity size comparable to light wavelength. Certain symmetry in the allocation of gain material leads to depletion of odd longitudinal modes that, in turn, ... We describe modeling the solid-state dye laser with the microcavity size comparable to light wavelength. Certain symmetry in the allocation of gain material leads to depletion of odd longitudinal modes that, in turn, increases the tunability range of the microlaser. We provide simple physical explanation for the modeling results. 展开更多
关键词 MODE Impact of cavity symmetry on mode suppression and increase of free spectral range in solid-state dye microlaser free
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A 12-bit 40 MS/s pipelined ADC with over 80 dB SFDR
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作者 魏琦 殷秀梅 +1 位作者 韩丹丹 杨华中 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2010年第2期59-63,共5页
This paper describes a 12-bit 40 MS/s calibration-free pipelined analog-to-digital converter(ADC),which is optimized for high spurious free dynamic range(SFDR) performance and low power dissipation.With a 4.9 MHz ... This paper describes a 12-bit 40 MS/s calibration-free pipelined analog-to-digital converter(ADC),which is optimized for high spurious free dynamic range(SFDR) performance and low power dissipation.With a 4.9 MHz sine wave input,the prototype ADC implemented in a 0.18-μm 1P6M CMOS process shows measured differential nonlinearity and integral nonlinearity within 0.78 and 1.32 least significant bits at the 12-bit level without any trimming or calibration.The ADC,with a total die area of 3.1×2.1 mm^2,demonstrates a maximum signal-to-noise distortion ratio(SNDR) and SFDR of 66.32 and 83.38 dB,respectively,at a 4.9 MHz analog input and a power consumption of 102 mW from a 1.8 V supply. 展开更多
关键词 analog-to-digital converter PIPELINE spurious free dynamic range
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High performance 14-bit pipelined redundant signed digit ADC
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作者 Swina Narula Sujata Pandey 《Journal of Semiconductors》 EI CAS CSCD 2016年第3期71-80,共10页
A novel architecture of a pipelined redundant-signed-digit analog to digital converter(RSD-ADC) is presented featuring a high signal to noise ratio(SNR), spurious free dynamic range(SFDR) and signal to noise plu... A novel architecture of a pipelined redundant-signed-digit analog to digital converter(RSD-ADC) is presented featuring a high signal to noise ratio(SNR), spurious free dynamic range(SFDR) and signal to noise plus distortion(SNDR) with efficient background correction logic. The proposed ADC architecture shows high accuracy with a high speed circuit and efficient utilization of the hardware. This paper demonstrates the functionality of the digital correction logic of 14-bit pipelined ADC at each 1.5 bit/stage. This prototype of ADC architecture accounts for capacitor mismatch, comparator offset and finite Op-Amp gain error in the MDAC(residue amplification circuit)stages. With the proposed architecture of ADC, SNDR obtained is 85.89 d B, SNR is 85.9 d B and SFDR obtained is 102.8 d B at the sample rate of 100 MHz. This novel architecture of digital correction logic is transparent to the overall system, which is demonstrated by using 14-bit pipelined ADC. After a latency of 14 clocks, digital output will be available at every clock pulse. To describe the circuit behavior of the ADC, VHDL and MATLAB programs are used. The proposed architecture is also capable of reducing the digital hardware. Silicon area is also the complexity of the design. 展开更多
关键词 pipelined ADC MDAC non-ideal errors signal to noise ratio(SNR) spurious free dynamic range(SFDR) signal to noise plus distortion(SNDR)
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