一种分道器在输送系统的应用

本文分析了输送系统的分道器种类及使用现状,针对输送效率问题从技术上比较了各种分道器的特点,并通过相关成功案例验证新型伺服分道器具有更明显的提速效果。

兰州润滑油厂1升2号机分道器改造及应用

兰州润滑油厂1升2号机是集机电仪于一体的生产包装线,主要承担0.9升和1升润滑油的包装任务。在其运行期间,分道器部分出现故障频次较高,为确保完成生产任务,保证经济效益,在坚持安全高效生产原则下,对1升2号包装线分道器部分进行合理改造。简化了机械构造,对其电气和控制程序部分也进行相应改进和调整,使机电仪一体协调工作,减少故障发生,提高生产效率。

第一现场

①9月29日,成都市在金沙遗址的街头举行“龙腾金沙”蓉城之秋,成都风情活动,从而拉开了成都市国庆文化系列活动的序幕。②10月9日,国际(萧山)钱江观潮节迎来最高潮,数万游客和当地群众目睹了钱江潮“涛似连山喷雪来”的壮丽景象。③10月7日,20名日本东京大轰炸遗孤访问团成员在大轰炸隧道惨案遗址凭悼重庆大轰炸的死难亡灵。④10月8日,在贵州省沿河土家族自治县乌江河黎芝峡附近的河漫滩上,纤夫们拉着船,在河滩乱石中艰难前行。据了解,乌江黎芝峡河段悬崖绝璧连绵,滩多水急船难行,因此在拉短滩途货运中可看到少量纤夫的身影。随着乌江流域最下游彭水水电站的即将修建,乌江河畔孕育的靠拉船为生的纤夫这一古老职业将永远退出历史舞台。⑤10月9日,三峡工程三期蓄水正式跨越148米,并直奔156米。这标志着三峡蓄水自成库以来,首次面对高水位运行。

韶钢3^#剪区域故障探析

对韶钢六轧厂 3#剪区域设备的调整要领、动作的工艺原理、工艺动作的控制参数、常见故障产生的原因进行了细致的分析 ;对如何减少、消除故障提出了相应的对策 ;总结了在交接班检查和轧制过程中的巡回点检时应注意的问题 ;对 3#剪区域设备提出了改进意见 .上述工作 ,使3#剪区域设备故障大大减少 ,从而促进了六轧厂的生产 ,最高班产超 850t,日产达 2 30 0t .

Numerical Simulation of Methane Distribution and Sensor Placement in 2-Dimension Roadway

In order to provide a theoretical basis for methane sensor placement in the vertical direction of a tunnel,the software Fluent was used to simulate methane distribution. A geometric roadway model was established and divided by grids. Methane distribution in both level and vertical sections was simulated using a realizable k-ε model with the Fluent software according to a conservation equation in a turbulent state,a turbulent kinetic energy equation and a turbulent dissipation rate equation. The realizable k-ε model and the Fluent software were used to simulate methane distribution according to the principle of the conservation equation in a state of turbulent flow. The results show that after overflow-ing,a methane level with a certain thickness is formed. Methane density curves at three specific levels were internally consistent and methane density at higher levels is denser than that at lower levels. Methane distribution becomes thinner in the direction of wind and methane in the vertical direction becomes uniform if wind speed is high. The distance be-tween sensors and roof should be less than 300 mm which is in agreement with mine safety regulations.

Study of the Opuntia ficus indica and Its Radioactive Potassium Content using the Gamma Spectrometry

Mexico is one of the largest producers of nopal （Opuntiaficus indica）. This ＂vegetable＂ is consumed on a daily basis by the Mexican population, being a source of food nutrients. Among its benefits, it is considered the content of potassium, which is essential for human life and health. In this study, it analyzes the content of potassium of the Mexican cactus （Opuntiaficus indica） grown in 5 different regions in the Mexican Basin, where 67% of the nopal is produced for human consumption. The used methodology is gamma spectrometry with Hyperpure Germanium detector （HPGe） and Multichannel Analyzer （MCA） with Maestro~ software. The results show interesting aspects on the concentration of potassium in the nopal. This concentration will primarily depend on： （a） the geological characteristics of the location where the nopal was grows; （b） that potassium concentrations may vary substantially from a region to another, with the same species of nopal as a reference and （c） that this concentration may also vary from one growing season to another.

XDH-I型半圆式田径场分道画线器的设计原理及其使用

XDH—Ⅰ型半圆式田径分道画线器的主体,主要是由横梁、标志杆和控制调节杆组成,运用数学和机械原理,通过调节控制调节杆,控制标志杆与横梁之间的夹角,以跑道内突沿外沿(或标志线外沿)为基准线,使标志杆沿之运动,获得横梁在跑道直段和弯道上的画线.它的使用将可降低工作强度、提高工效,适用于半圆式田径场的分道画线;既可一次性地画出跑道的各分道线,又能达到规则要求.本文着重介绍了其设计原理、使用方法和适用范围.

AN ITERATIVE PARTICLE FILTER SIGNAL DETECTOR FOR MIMO FAST FADING CHANNELS

For flat fast fading Multiple-Input Multiple-Output(MIMO) channels,this paper presents a sampling based channel estimation and an iterative Particle Filter(PF) signal detection scheme. The channel estimation is comprised of two parts:the adaptive iterative update on the channel distribution mean and a regular update on the "adaptability" via pilot. In the detection procedure,the PF is employed to produce the optimal decision given the known received signal and the sequence of the channel samples,where an asymptotic optimal importance density is constructed,and in terms of the asymptotic update order,the Parallel Importance Update(PIU) and the Serial Importance Update(SIU) scheme are performed respectively. The simulation results show that for the given fading channel,if an appropriate pilot mode is selected,the proposed scheme is more robust than the conventional Kalman filter based superimposed detection scheme.

Simulation of Liquid Argon Flow along a Nanochannel： Effect of Applied Force

Liquid argon flow along a nanochannel is studied using molecular dynamics (MD) simulation in this work.Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) is used as the MD simulator.The effects of reduced forces at 0.5,1.0 and 2.0 on argon flow on system energy in the form of system potential energy,pressure and velocity profile are described.Output in the form of three-dimensional visualization of the system at steady-state condition using Visual Molecular Dynamics (VMD) is provided to describe the dynamics of the argon atoms.The equilibrium state is reached after 16000 time steps.The effects on system energy,pressure and velocity profile due to reduced force of 2.0 (F2) are clearly distinguishable from the other two lower forces where sufficiently high net force along the direction of the nanochannel for F2 renders the attractive and repulsive forces between the argon atoms virtually non-existent.A reduced force of 0.5 (F0.5) provides liquid argon flow that approaches Poiseuille (laminar) flow as clearly shown by the n-shaped average velocity profile.The extension of the present MD model to a more practical application affords scientists and engineers a good option for simulation of other nanofluidic dynamics processes.

Turbidity measurement based on a multi-wavelength spectral sensor

A method of measuring turbidity based on a multi-wavelength spectral sensor is proposed by using SFH4737 broad-band infrared LED,a multi-wavelength spectral sensor and independently developed data processing software.Combining multiple wavelength data from the sensor,the unitary and multivariate fitting models were constructed to investigate the relationship among light intensity information,absorbance and turbidity,respectively.The turbidity of the actual water bodies was measured separately by using proposed method and a commercially visible spectrophotometer.The independent-samples T test(p>0.05)showed that there was no significant difference between the method in this paper and the standard assay method.The method is simple and inexpensive,and can be applied to the rapid detection of water turbidity,providing a new way of industrial online measurement.

Throughput analysis for relay-aided interference channel in cognitive radio networks

This paper considers a two-user Gaussian interference channel aided by a single relay. Two source-destination pairs and the relay share a single common chaunel, and the relay assists both sources in communicating the messages to their respective destinations. This paper mainly focuses on the ＂amplify-and-forward＂ （AF） relaying strategy for relay, and derives upper bound and lower bound on achievable sum rate accordingly. Next, the application of the above model in cognitive radio （CR） networks is considered. The schemes that can ensure the coexistence of the secondary user with the primary user are proposed, in the sense that there is no rate degradation for the primary user due to sharing of the channel. Further, the throughput of the secondary user in different communication scenarios is investigated.

Resource allocation for relay assisted cognitive radio network

Different schemes, which performed channel, power and time allocation to enhance the network performance of overall end-to-end throughput for cooperative cognitive radio network, were investigated. Interference temperature limit of corresponding primary users was considered. Due to the constraints caused by multiple dual channels, the power allocation problem is non-convex and NP-hard. Based on geometric programming (GP), a novel and general algorithm, which turned the problem into a series of GP problems by logarithm approximation (LASGP), was proposed to efficiently solve it. Numerical results verify the efficiency and availability of the LASGP algorithm. Solutions of LASGP are provably convergent and globally optimal point can be observed as well as the channel allocation always outperforms power or timeslot allocation from simulations. Compared with schemes without any allocation, the scheme with joint channel, power and timeslot allocation significantly increases the overall end-to-end throughput by no less than 70% under same simulation conditions. This scheme can not only maximize the throughput by increasing total maximum power of relay node, but also outperform other resource allocation schemes when lower total maximum power of source and relay nodes is restricted. As the total maximum power of source node increases, the scheme with joint channel and timeslot allocation performs best in all schemes.

A Modified Methodology to Evaluate Viscosity of Non-Newtonian Liquid Foods with a Flow Channel Instrument

Through experimental analysis of the liquid flows in a flow channel instrument, prompt evaluation of the physically defined viscosity of non-Newtonian liquid foods was investigated for development into a structurally simple and easy-to-use viscometer. For Newtonian and non-Newtonian test liquids, a relation between the friction coefficient and Reynolds number, which was dimensionless as derived from an expression of analysis as a gravity current, indicated a condition under which the flow in the instrument was laminar and under which an average shear rate was on the order of less than 1 s~. Prediction organized based on this empirical relation reproduced practically the flow curve determined for the liquid foods using a rotor type viscometer. Utilization of the channel instrument as a viscometer was formulated in terms of physical meanings of measurements such as the flow length and elapsed time.

PARTIAL CHANNEL STATE INFORMATION BASED SUB-OPTIMAL SDMA STRATEGIES IN MULTIPLE RELAY CHANNELS

Joint sub-optimization of cooperative relays in Multiple-Input and Multiple-Output (MIMO) multiple relays aided communication system is discussed in this paper. Because the instantaneous channel state information of all source-relay channels and all relay-user channels is difficult to get at each relay node, an unjoined solution is designed according to the channel state information of that relay only. Then a multi-user loading algorithm is proposed to utilize the space diversity through multi-relay transmission. The simulation results show that with the newly proposed multi-user loading algorithm, the unjoined solution can achieve better system performance comparing with joint one in low SNR. However, the complexity of the former is much lower, for only partial CSI is needed.

Low Noise Distributed Amplifiers Using a Novel Composite-Channel GaN HEMTs

Low noise distributed amplifiers （DAs） using the novel low noise composite-channel Al0.3 Ga0.7N/ml0.05 Ga0.95 N/ GaN HEMTs （CC-HEMTs） with 1μm-gate-length are designed and fabricated. Simulated and measured results of the DAs are characterized. The measured results show that the low noise DAs have input and output VSWR （voltage standing wave ratio） of less than 2.0,associated gain of more than 7.0dB and gain ripple of less than ldB in the frequency range from 2 to 10GHz. Noise figure of the DAs is less than 5dB in the frequency range from 2 to 6GHz,and less than 6.5dB in the frequency range from 2 to 10GHz. The measured results agree well with the simulated ones.

杭州BRT全体验

6月27日,记者体验了全国仅有的两条BRT线路之一的杭州BRT线路。杭州的BRT线路全长近28公里,整条快速公交的线路从杭州西端的黄龙体育中心站开始,横穿杭州市的东西两端。

Deterministic quantum communication using the symmetric W state

This study proposes a new coding function for the symmetric W state. Based on the new coding function, a theoretical protocol of deterministic quanama communication （DQC） is proposed. The sender can use the proposed coding function to encode his/her message, and the receiver can perform the imperfect Bell measurement to obtain the sender＇s message. In comparison to the existing DQC protocols that also use the W class state, the proposed protocol is more efficient and also more practical within today＇s technology. Moreover, the security of this protocol is analyzed to show that any eavesdropper will be detected with a very high probability under both the ideal and the noisy quantum channel.

Over 15.5% efficiency organic solar cells with triple sidechain engineered ITIC

Bulk-heterojunction(BHJ)organic solar cells(OSCs)showcase great advantages in device fabrication via low-cost and convenient solution-processing techniques for diverse applications(e.g.,flexible and semitransparent devices)[1,2].

Necessary and sufficient conditions of the rendezvous between a single spacecraft and three non-coplanar Walker constellation satellites

The probability of the rendezvous between a single spacecraft and three non-coplanar constellation satellites is studied,and the necessary and sufficient conditions of the rendezvous without orbital maneuver are deduced.The rendezvous orbit design can be transformed into the patching of two spacecraft orbits,either of which can achieve the rendezvous with two satellites.Firstly,due to the precious quality of spherical geometry,the unique existence of the rendezvous orbit for two constellation satellites is proved.Then,according to the difference between equispaced and non-equispaced orbital planes of three satellites,the necessary and sufficient conditions are given respectively,and the calculating method of the spacecraft orbit is proposed.At last,the constraint conditions between two different rendezvous orbits is derived,while the relative position of two groups of objects are under specific distribution.The results can be applied to the rendezvous between a single spacecraft and multiple constellation satellites without orbital maneuver.

High resolution scanning gate microscopy measurements on InAs/GaSb nanowire Esaki diode devices

Gated transport measurements are the backbone of electrical characterization of nanoscale electronic devices. Scanning gate microscopy （SGM） is one such gating technique that adds crucial spatial information, accessing the localized properties of semiconductor devices. Nanowires represent a central device concept due to the potential to combine very different materials. However, SGM on semiconductor nanowires has been limited to a resolution in the 50-100 nm range. Here, we present a study by SGM of newly developed III-V semiconductor nanowire InAs/GaSb heterojunction Esaki tunnel diode devices under ultra-high vacuum. Sub-5 nm resolution is demonstrated at room temperature via use of quartz resonator atomic force microscopy sensors, with the capability to resolve InAs nanowire facets, the InAs/GaSb tunnel diode transition and nanoscale defects on the device. We demonstrate that such measurements can rapidly give important insight into the device properties via use of a simplified physical model, without the requirement for extensive calculation of the electrostatics of the system. Interestingly, by precise spatial correlation of the device electrical transport properties and surface structure we show the position and existence of a very abrupt （〈10 nm） electrical transition across the InAs/GaSb junction despite the change in material composition occurring only over 30-50 nm. The direct and simultaneous link between nanostructure composition and electrical properties helps set important limits for the precision in structural control needed to achieve desired device performance.