基于发育阶段的设施黄瓜水肥一体化技术

水肥一体化技术是未来农业生产中具有广阔前景的新技术,设施蔬菜最具潜力发展水肥一体化技术。设施黄瓜水肥一体化技术的核心是借助压力灌溉系统,将完全水溶性固体肥料或液体肥料,按设施黄瓜生长各阶段对养分的需求和土壤养分的供给状况,配兑而成的肥液与灌溉水融为一体,适时、定量、均匀、准确地输送到设施黄瓜根部土壤。本文简要介绍了基于发育阶段的设施黄瓜水肥一体化技术要点,主要包括施肥总量的推荐方法、基肥用量的确定方法、滴灌水量的运筹方案、滴灌追肥的运筹方案等内容。该技术节水40%以上,节肥30%以上,提高氮肥利用率40%以上,增产10%以上,增收15%以上。

浅谈机电一体化技术在汽车设计中的应用

经济的发展和汽车科技水平的提高大大加快了汽车机电一体化技术的发展速度,这对汽车产业的发展具有重要的推动作用。在汽车设计中应用机电一体化技术可以将汽车的性价比大大提升。但是在汽车设计中应用机电一体化技术仍然存在一些问题,对其造成不利影响。所以本文主是对汽车设计中机电一体化应用的进行了具体的研究。

工程机械中机电一体化技术的运用

机电一体化技术作为现代科技发展下的产物,以其独特优势在工程机械领域中得到了广泛应用,提高了工程机械设备的运行性能与安全性,减少了成本投入,还增强了工程机械企业的市场竞争力.那么机电一体化技术在工程机械企业中的实践应用具体表现在哪些方面？今后将朝着什么方向发展？这些均是本文重点探究内容.

机电一体化技术的发展趋势及应用分析

近年来,随着科学技术的不断发展与进步,以及机电一体化技术在各领域中的广泛应用,我国的机电一体化技术迎来了快速发展的新机遇。在交通工程中,通过机电一体化技术的应用,可以促进我国道路交通事业实现跨越式发展。文章就机电一体化技术在交通工程中的应用及发展趋势展开全面分析。

燃煤烟气脱硫脱硝一体化技术的应用研究

针对燃煤烟气脱硫脱硝一体化技术中应用现状,如材料吸附力较低、化学危险性较大等,进行科学分析,本文详细介绍联合脱硫脱硝技术与同时脱硫脱硝一体化技术,干式吸附再生技术、络合吸收法与光催化法的具体应用,希望能够给相关工作人员提供一定的参考。

FSU机械工程技术专业课程体系构架与实践教学条件建设的借鉴与启示

通过参加美国菲利斯州立大学(简称FSU)骨干教师教育教学提升培训项目的培训,对比研究FSU机械工程技术专业与长沙民政职业技术学院(简称CSMZ)机电一体化技术专业课程体系构架与实践教学条件,分析它们之间的异同。借鉴FSU建设经验,完善CSMZ机电一体化技术专业技能与课程设置的对应关系,将FSU机械工程技术专业的机械设计与制造类课程,融入到CSMZ机电一体化技术专业的课程体系,同时改善校内与校外实践教学条件,提高机电一体化技术专业整体办学水平。

RESEARCH OF VOXELIZATION PROCESS IN SWEPT-VOLUME TECHNIQUE

Now the image display techniques have made great progress. The planar display and a fully new true 3-D volumetric display technique are rapidly researched and come into the application. A method based on the voxel makes the observer able to get a true 3-D effect freely without any additional facilities. This paper introduces the basic form of the swept-volume display technique and discusses its voxelization process. By the translational motion prototype, this paper emphasizes how to get the voxel mapping matrix. The translated image data are the data of the beam source deflections. Finally the voxel ordering and the optimizing are also discussed.

Determination of Structure and Polarity of Si C Single Crystal by X-Ray Diffraction Technique

Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam ple has a6 H modification.The difference between the integrated intensities m easured byω scan in the triple- axis diffraction set- up finds some convincing evidence that the surface is either a Si- terminated face or C- terminated face.The experi- mental ratios of| F( 0 0 0 L) | 2 / | F( 0 0 0 L) | 2 are in good agreem entwith the calculated ones after the dispersion cor- rections to the atomic scattering factors( L=6 ,12 and18,respectively) .Thus,this m easurem ent technique is con- venient for the application of the materials with remarkable surface polarity.

Hydrogen storage properties of Mg-TiO_2 composite powder prepared by arc plasma method

Mg-based Mg-TiO2 composite powder was prepared by arc plasma evaporation of the Mg＋5%TiO2 mixture followed by passivation in air. ICP, XRD and SEM techniques were used to characterize the composition, phase components and microstructure of the composite powder. The hydrogen sorption properties of the composite powder were investigated by DSC and PCT techniques. According to the data from PCT measurements, the hydrogenation enthalpy and entropy changes of the composite powder are calculated to be-71.5 kJ/mol and-130.1 J/（K·mol）, respectively. Besides, the hydrogenation activation energy is determined to be 77.2 kJ/ mol. The results indicate that TiO2 added into Mg by arc plasma method can act as a catalyst to improve the hydrogen sorption kinetic properties of Mg.

Necessary and Sufficient Conditions for Consensus in Third Order Multi-Agent Systems

We deal with a consensus control problem for a group of third order agents which are networked by digraphs.Assuming that the control input of each agent is constructed based on weighted difference between its states and those of its neighbor agents, we aim to propose an algorithm on computing the weighting coefficients in the control input. The problem is reduced to designing Hurwitz polynomials with real or complex coefficients. We show that by using Hurwitz polynomials with complex coefficients, a necessary and sufficient condition can be obtained for designing the consensus algorithm. Since the condition is both necessary and sufficient, we provide a kind of parametrization for all the weighting coefficients achieving consensus. Moreover, the condition is a natural extension to second order consensus, and is reasonable and practical due to its comparatively decreased computation burden. The result is also extended to the case where communication delay exists in the control input.

Experimental Research on Single-Pass SHG from Periodically Poled LiNbO_3 Crystal

Quasi phase matching (QPM) periodical poled LiNbO 3(PPLN) is designed and successfully fabricated to enable second harmonic generation(SHG).The samples were Z cut 0.5 mm thick and grating period is Λ=6.8 μm for the first order QPM of continual wave λ=1.064 μm which is emitted by Nd∶YAG laser at room temperature 27 ℃. The output single pass SHG power was tested by an authorized optical system. The normalized max conversion efficiency is calculated to be 0.25 0 0(W·cm) -1 .The fabrication and parameters calculated method are introduced, and testing scheme is described in this paper. Even some ideas to improve conversion efficiency are offered.

Development of 8-inch Key Processes for Insulated-Gate Bipolar Transistor

Based on the construction of the 8-inch fabricat ion line, advanced process technology of 8-inch wafer, as well as the fourth-generation high-voltage double-diffused metal-oxide semiconductor(DMOS+) insulated-gate bipolar transistor(IGBT) technology and the fifth-generation trench gate IGBT technology, have been developed, realizing a great-leap forward technological development for the manufacturing of high-voltage IGBT from 6-inch to 8-inch. The 1600 A/1.7 kV and 1500 A/3.3 kV IGBT modules have been successfully fabricated, qualified, and applied in rail transportation traction system.

Trimming self-intersections in swept volume solid modeling

Swept volume solid modeling has been applied to many areas such as NC machining simulation and verification, robot workspace analysis, collision detection, and CAD. But self-intersections continue to be a challenging problem in the boundary representation of swept volume solids. A novel algorithm is presented in this paper to trim self-intersection regions in swept volume solids modeling. This trimming algorithm consists of two major steps: (1) roughly detecting self-intersection regions by checking intersections or overlapping of the envelop profiles; (2) splitting the whole envelop surfaces of the swept volume solid into separate non-self-intersecting patches to trim global self-intersections, and to trim local self-intersections, dividing local self-intersecting regions into patches and replacing self-intersecting patches with non-self-intersecting ones. Examples show that our algorithm is efficient and robust.

SDSA: A Framework of a Software-Defi ned Security Architecture

The fact that the security facilities within a system are closely coupled and the security facilities between systems are unconnected results in an isolated protection structure for systems, and gives rise to a serious challenge to system security integrations and system controls. Also, the need for diversified services and flexible extensions of network security asks for more considerations and contribu?tions from the perspective of software engineering in the process of designing and constructing security systems. Based on the essence of the virtualization technique and the idea of software-defined networks, we in this paper propose a novel software-defi ned security architecture for systems. By abstracting the traditional security facilities and techniques, the proposed security architecture provides a new, simple, effective, and programmable framework in which security operations and security controls can be decoupled, and thereby reduces the software module sizes, decreases the intensity of software deve?lopments, and improves the security extensibility of systems.

Design of small-area multi-bit antifuse-type 1 kbit OTP memory

A multi-bit antifuse-type one-time programmable （OTP） memory is designed, which has a smaller area and a shorter programming time compared with the conventional single-bit antifuse-type OTP memory. While the conventional antifuse-type OTP memory can store a bit per cell, a proposed OTP memory can store two consecutive bits per cell through a data compression technique. The 1 kbit OTP memory designed with Magnachip 0.18 μm CMOS （complementary metal-oxide semiconductor） process is 34% smaller than the conventional single-bit antifuse-type OTP memory since the sizes of cell array and row decoder are reduced. And the programming time of the proposed OTP memory is nearly 50% smaller than that of the conventional counterpart since two consecutive bytes can be compressed and programmed into eight OTP cells at once. The layout area is 214 μm× 327 μ,, and the read current is simulated to be 30.4 μA.

Waveforms analysis and optimization of new electro-hydraulic excitation technology

A new electro-hydraulic exciter that consists of rotary valve and micro-displacement double-functioned hydraulic cylinder was proposed to realize different kinds of waveforms.Calculated fluid dynamics(CFD) simulation of rotary valve orifice reveals that orifice exists the two-throttle phenomenon.According to the finding,the revised flow area model was established.Vibration waveforms analysis was carried out by means of mathematic model and the related experiments were validated.Furthermore,as a new analysis indicator,saturation percentage was introduced first.The experimental results indicate that the revised flow area model is more accurate compared to the original one,and vibration waveforms can be optimized through suitable spool parameters and the revised cylinder structure.

Three-dimensional image reconstruction in capsule endoscopy

To date,limited research has been carried out in developing methods and materials that offer three-dimensional(3-D) representation of the digestive tract.In the field of capsule endoscopy(CE),hardware approaches have been developed that provide real time both 3-D information and texture using an infrared projector and a complementary metal oxide semiconductor camera.The major drawbacks of this system are its size,power consumption and packaging issues.A software approach to approximate a 3-D representation of digestive tract surface utilising current CE technology has been proposed.The algorithm utilizes the Shape from Shading technique and seem to provide promising results for polypoid structures and angioectasias.Further clinical evaluation is currently under way.

Stability of the Newton-Like algorithm in optimization flow control

The stability of the Newton-like algorithm in optimization flow control is considered in this paper. This algorithm is proved to be globally stable under a general network topology by means of Lyapunov stability theory,without considering the round trip time of each source. While the stability of this algorithm with considering the round trip time is analyzed as well. The analysis shows that the algorithm with only one bottleneck link accessed by several sources is also globally stable,and all trajectories described by this algorithm ultimately converge to the equilibrium point.

High-quality multi-resolution volume rendering in medicine

In order to perform a high-quality interactive rendering of large medical data sets on a single off-the-shelf PC, a LOD selection algorithm for multi-resolution volume rendering using 3D texture mapping is presented, which uses an adaptive scheme that renders the volume in a region-of-interest at a high resolution and the volume away from this region at lower resolutions. The algorithm is based on several important criteria, and rendering is done adaptively by selecting high-resolution cells close to a center of attention and low-resolution cells away from this area. In addition, our hierarchical level-of-detail representation guarantees consistent interpolation between different resolution levels. Experiments have been applied to a number of large medical data and have produced high quality images at interactive frame rates using standard PC hardware.

A communication-aware scheduling algorithm for heterogeneous systems

Previous work mostly employs an ideal system model that assumes fully connected processors and concurrent communication, which leads to inaccurate and inegicient schedule results. In this paper, a new scheduling model which integrates the communication awareness was proposed. Then, a novel scheduling algorithm based on list heuristic was put forward for the new model, which can produce optimal schedule by serializing the communications edges. Experimental results show that the accuracy and efficiency of the new model and algorithm are significantly improved.