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基于OCDM（光码分复用）技术和MPLS（多协议标签交换）技术,采用分离编解码方案对可并行光码标签路由技术进行研究。利用光极性特性实现标签与净荷的分离,采用FBG（光纤布拉格光栅）编码器对数据进行编解码。由于系统采用码分复用,允许不同净荷在时间上重叠,同一波长的OCDM标签路径在核心路由器中并行处理,提高了系统的吞吐量。

文章提出了光纤通信网与传感网融合的设想,即利用已有光纤接入网的通信信道,让传感网络发出的传感信号在光纤接入网中传输。首先分析了这种设想的可行性,然后提出了按固定帧复用的方式对传感信号和通信信号进行耦合,并根据已有光纤接入网的结构建立了该系统的网络基本结构,重点分析了传感信号与通信信号复用时的时隙及带宽分配问题。

Copyright of Chinese Journal of Rehabilitation Medicine is the property of China Association of Rehabilitation Medicine, China-Japan Friendship Hospital and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The mobile flume has the advantages of not easy to be silted up and can be moved and reused in many places, etc. Compared with the fixed type, the streamlined shape of the measuring flume has good hydraulic performance, and the diffusion section of the flume has a great influence on the hydraulic performance, however, there is a lack of research on the design principle and method of the diffusion section at present. In order to study the influence of flume structure on hydraulic properties, and to provide theoretical guidance for the design of streamlined flume structure, This paper establishes a D40Ushaped channel simulation model, and then uses FLOW-3D to simulate the semi-elliptical with semi-elliptical, semi-elliptical with parabolic, semi-elliptical with arc, semi-elliptical with Myring curve, and fish-shaped flume under flow rates of 35, 45, and 55 L/s. Furthermore, the accuracy effect of numerical simulation is verified by prototype test, and then the design principle and method of diffusion section are discussed. Finally, based on the isight platform, the semi-elliptical with Myring curve and fish-shaped flume with better hydraulic performance are optimized. The results show that the relative error between the numerical simulation and the experimental water depth is 0.1%-1.3% and the relative errors of velocity in upstream, throat and downstream sections are 0.19%-6.63%, 0.06%-6.15% and 0.02%-6.22% at 45 L/s flow rate, respectively. The numerical simulation results have high accuracy. The Froude number in the upstream of the five flumes is less than 0.5, and the maximum backwater height is 5.71 cm, which meets the requirements of flow measurement accuracy and channel safety. Among them, the head loss and backwater height of the semi-elliptical with Myring curve flume are the lowest, the critical submergence degree of the semi-elliptical with semi-elliptical flume is the highest, and the Froude number is the smallest. The design principle of the diffusion section of the flume is: under the condition of slightly reducing the critical submergence degree, the first half of the diffusion section is designed as a curve with larger curvature to reduce the upstream backwater; the second half is designed as a curve with opposite curvature and smaller curvature to improve the flow state, smooth the water flow and reduce the head loss. After optimization, the curvature of the first half of the semi-ellipse with Myring curve and the fish-shape flume increases, and the curvature of the second half decreases, the backwater and Froude number are reduced, and the head loss is reduced by 5.5% and 6.3%, respectively. The study can provide theoretical guidance for the design and optimization of streamlined measuring tank structures. [ABSTRACT FROM AUTHOR]

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Uneven frozen heave can cause some damage to the canal lining structure, particularly in the frozen soil in the north cold region of China. The frost-heaving damage of canal lining is closely related to the lining-frozen soil contact action. Some relations of contact consist of the contact surface, such as the freezing constraint, and friction slip. The lining stress can also depend directly on the separate conditions. However, the current simulation of the lining-frozen soil contact is mostly focused on the steady state. It is still lacking in the experimental verification of the mechanical parts. Taking the integral U-shaped canal frost heaving damage experiment in the Hetao irrigation area as the prototype, this research aims to construct the canal frost heave model with/without the contact relationship. Finite element (FE) software ABAQUS was selected to simulate the frostheaving damage process of the model. Two models were evaluated to compare the experimentally monitored data from the subsoil temperature field, layered frost heave displacement, and soil stress. A systematic analysis was made to determine the stress state and damage mechanism of the canal lining. The experimental and simulation were integrated to clarify the influence of lining-frozen soil separation and sliding process on the frost-heaving damage of the canal. The results show that the simulation considering the contact model was more consistent with the field test conditions, compared with no contact. There were the basically same distributions of temperature field between the experiment and simulation with/without contact. Specifically, the simulated freezing depths of the shady and sunny slopes increased by 2.44% and 1.68%, respectively, whereas, the freezing depth of the canal bottom decreased by 4.26%, compared with the experimental. Small errors were found between the experimental and simulated subsoil and lining normal frost heave displacement. The consideration of contact posed a weak limiting effect on the canal slope subsoil freezing. The average relative errors were 7.1% and 13.9% between the simulated and experimental data with/without contact, respectively. Moreover, the simulated stress peak at the side slope reached 3.3 times of the contact model. The voids were generated between the canal bottom lining and the foundation soil in the experimental and the considered contact model. By contrast, there were continuously increasing tensile stresses in the simulations without considering contact. The separation and sliding process between the lining-frozen soil contact surface were visualized dynamically to combine the considered contact model with the experiment. The lining at the bottom of the canal was the first to separate from the subsoil after the onset of frost heave, due to the inhomogeneity of the subsoil frost heave. There was no transferred contact stress. After that, relative sliding occurred between the lining and the frozen soil at the side slope. As such, the originally restrained lining stress was released. More importantly, the frost heave displacement of the lining was still increasing in the process of stress release. The sliding process changed the stress development trend from the "force increase" to the "force release". The peak values of normal stress were reduced by 903% and 164% on the upper and lower surfaces of the lining under the releasing force of the simulated slip in the considering contact model, compared with the simulation without considering contact. Meanwhile, the peak value of tangential force was reduced by 248% on the lower surface. All peak stresses occurred on the slightly shady slope at the bottom of the canal, where the frost-heaving damage was more likely to occur. The finding can provide a strong reference for the design and structural optimization of the frost heave prevention of canals in cold regions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of China Medical University is the property of Journal of China Medical University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Southwest China Journal of Agricultural Sciences is the property of Editorial Department of Southwest China Journal of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ｔｅｃｈｎｏｌｏｇｉｃａｌ ｍｅｔｈｏｄｓ ｆｏｒ ｉｍｐｒｏｖｉｎｇ ｉｒｒｉｇａｔｉｏｎ ｅｆｆｉｃｉｅｎｃｙ ａｒｅ ｗｉｄｅｌｙ ｒｅｇａｒｄｅｄ ａｓ ｅｆｆｅｃｔｉｖｅ ｆｏｒ ｒｅｄｕｃｉｎｇ ｗａｔｅｒ ｕｓｅ． Ｈｏｗｅｖｅｒ， ｉｔ ｈａｓ ｎｏｔ ａｃｈｉｅｖｅｄ ｔｈｅ ｅｘｐｅｃｔｅｄ ｗａｔｅｒ ｓａｖｉｎｇｓ； ｗａｔｅｒ ｕｓｅ ｉｎ ｓｏｍｅ ａｒｅａｓ ｅｖｅｎ ｉｎｃｒｅａｓｅｄ． Ｔｈｉｓ ｓｉｔｕａｔｉｏｎ ｉｍｐｌｉｅｓ ｔｈａｔ ｔｈｅ ｓｏ⁃ｃａｌｌｅｄ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔ ｍａｙ ｏｃｃｕｒ， ｗｈｉｃｈ ｍｅａｎｓ ｔｈｅ ｅｘｐｅｃｔｅｄ ｗａｔｅｒ ｓａｖｉｎｇｓ ａｒｅ ｏｆｆｓｅｔ ｂｙ ｔｈｅ ａｄｄｉｔｉｏｎａｌ ｗａｔｅｒ ｄｅｍａｎｄ ａｒｉｓｉｎｇ ｆｒｏｍ ａｇｒｉｃｕｌｔｕｒａｌ ｏｕｔｐｕｔ ｉｎｃｒｅａｓｉｎｇ． Ｒｅｓｅａｒｃｈ ｏｎ ｉｒｒｉｇａｔｉｏｎ ｅｆｆｉｃｉｅｎｃｙ ｉｍｐｒｏｖｅｍｅｎｔ′ｓ ｅｆｆｅｃｔ ｏｎ ｗａｔｅｒ ｓａｖｉｎｇｓ ｈａｓ ｐａｌｐａｂｌｅ ｂｅｎｅｆｉｔｓ ｎｏｗａｄａｙｓ． Ｎｅｖｅｒｔｈｅｌｅｓｓ， ｔｈｅ ｌｉｔｅｒａｔｕｒｅｓ ｏｎ ｔｈｅ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔ ｏｆ ｉｒｒｉｇａｔｉｏｎ ｗａｔｅｒ ｎｏｔ ｂｅｅｎ ｒｅｖｉｅｗｅｄ ｓｙｓｔｅｍａｔｉｃａｌｌｙ． Ｔｈｉｓ ｐａｐｅｒ ｒｅｖｉｅｗｓ ｔｈｅｓｅ ｌｉｔｅｒａｔｕｒｅｓ ｆｒｏｍ ｔｈｅｓｅ ａｓｐｅｃｔｓ ｏｆ ｔｈｅ ｆｏｌｌｏｗｉｎｇ： ａ ｄｅｆｉｎｉｔｉｏｎ ｏｆ ｗａｔｅｒ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔ， ｓｃａｌｅ ｅｆｆｅｃｔｓ ｏｆ ｗａｔｅｒ ｓａｖｉｎｇｓ， ａｎｄ ｔｈｅ ｒｅｂｏｕｎｄ ｍｅｃｈａｎｉｓｍ ａｎｄ ｍａｇｎｉｔｕｄｅ ｏｆ ｔｈｅ ｗａｔｅｒ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔ． Ｔｈｅ ｉｒｒｉｇａｔｉｏｎ ｗａｔｅｒ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔ ｎｅｅｄｓ ｔｏ ｂｅ ｒｅｓｅａｒｃｈｅｄ ｆｕｒｔｈｅｒ， ａｎｄ ｃａｎｎｏｔ ｂｅ ｓｔｕｄｉｅｄ ｗｉｔｈ ｔｈｅ ｆｒａｍｅｗｏｒｋ ａｎｄ ｍｅｔｈｏｄ ｆｏｒ ｅｎｅｒｇｙ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔｓ， ｄｕｅ ｔｏ ｔｈｅ ｍｅａｓｕｒｉｎｇ ｃｏｍｐｌｅｘｉｔｙ ｏｆ ｗａｔｅｒ ｕｓｅ， ｓａｖｉｎｇｓ ａｎｄ ｅｆｆｉｃｉｅｎｃｙ． Ｆｕｔｕｒｅ ｒｅｓｅａｒｃｈ ａｒｅａｓ ｓｈｏｕｌｄ ｆｏｃｕｓ ｏｎ ｔｈｅ ｆｏｌｌｏｗｉｎｇ： ① ｐｒｏｖｉｄｉｎｇ ａ ｃｌａｒｉｆｉｅｄ ｄｅｆｉｎｉｔｉｏｎ ｏｆ ｉｒｒｉｇａｔｉｏｎ ｗａｔｅｒ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔ， ａｓ ｔｏ ｄｉｓｔｉｎｇｕｉｓｈ ｔｈｅ ｈｙｄｒｏｌｏｇｉｃａｌ ａｎｄ ｅｃｏｎｏｍｉｃ ｒｅｂｏｕｎｄ， ｗａｔｅｒ ｕｓｅ ａｎｄ ｃｏｎｓｕｍｐｔｉｏｎ ｒｅｂｏｕｎｄｓ， ａｎｄ ｔｈｅ ｇｅｎｅｒａｌ ｒｅｂｏｕｎｄ ａｎｄ ｔｈｅ ｂａｃｋｆｉｒｅ ｅｆｆｅｃｔｓ； ② ｄｅｅｐｌｙ ｓｔｕｄｙ ｔｈｅ ｍｅｃｈａｎｉｓｍ ｏｆ ｉｒｒｉｇａｔｉｏｎ ｗａｔｅｒ ｒｅｂｏｕｎｄ； ③ ｄｅｖｅｌｏｐ ａ ｒｅａｓｏｎａｂｌｅ ｍｅｔｈｏｄ ｆｏｒ ｃａｌｃｕｌａｔｉｎｇ ｔｈｅ ｉｒｒｉｇａｔｉｏｎ ｗａｔｅｒ ｒｅｂｏｕｎｄ ｅｆｆｅｃｔ． [ABSTRACT FROM AUTHOR]

Copyright of Tianjin Medical Journal is the property of Tianjin Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tianjin Medical Journal is the property of Tianjin Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)