测试仪器对产品质量全过程控制的重要性

为了提升中国纺织企业的国际竞争力,通过合理配棉、稳定配棉和量化半制品过程控制进而实现控制纺纱成本及纱线质量,分析了国内棉花检测和过程控制的现状,详细介绍了普瑞美高精度全系列棉纺测试仪器,重点阐述了最精确的原棉和工艺质量管理系统aQura的原理和应用实例。指出:棉花在纱线成本中所占的比例,中国是66%,而世界平均水平仅55%;提高纱线质量、优化工艺、降低成本对纺纱厂来说极为重要,如何在管理中节约原材料,如何持续稳定地控制产品质量刻不容缓;运用高精度的测试仪器对纺纱全过程进行控制可以实现质量和成本的平衡。

名优茶加工机械的发展现状和趋势

在分析了名优茶机械加工的重要作用、名优茶加工机械的发展过程和现状的基础上,指出名优茶加工机械存在的不足,提出了名优茶加工机械的发展趋势。

Influence of carbon and yttrium co-doping on the photocatalytic activity of mixed phase TiO_2

Mixed phase TiO2photocatalysts doped with C and Y were synthesized by a sol‐gel process.The effects of C and Y doping and annealing temperatures on the structural and optical properties,and photocatalytic activity were investigated.We found that both C and Y doping can broaden the absorption spectrum of TiO2to the visible light region and inhibit recombination of photogenerated electron/hole pairs.The incorporation of Y into the TiO2lattice inhibited growth of crystalline grains,which increased the specific surface area and enhanced the photocatalytic activity.The photocatalytic performance of the samples was investigated in the photocatalytic degradation of methyl blue under visible light irradiation.The rate of methyl blue degradation over the(C,Y)‐co‐doped TiO2sample was much higher than those of undoped TiO2,C‐TiO2,and Y‐TiO2.Additionally,the apparent first‐order rate constant of the co‐doped sample was3.5times as large as that of undoped mix phase TiO2under the same experimental conditions.The enhanced photocatalytic activity can be attributed to the synergic effect of(C,Y)‐co‐doping and the formation of an appropriate crystalline structure.

A Method for Surveying Control Network Optimization Based on Reliability Properties

Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying control network simulation optimization design is proposed. This method is based on the inner reliability index of the observation values.

Improving Centralized Path Calculation Based on Graph Compression

Shortest-path calculation on weighted graphs are an essential operation in computer networks. The performance of such algorithms has become a critical challenge in emerging software-defined networks(SDN),since SDN controllers need to centralizedly perform a shortest-path query for every flow,usually on large-scale network. Unfortunately,one of the challenges is that current algorithms will become incalculable as the network size increases. Therefore, inspired by the compression graph in the field of compute visualization,we propose an efficient shortest path algorithm by compressing the original big network graph into a small one, but the important graph properties used to calculate path is reserved. We implement a centralized version of our approach in SDN-enabled network,and the evaluations validate the improvement compared with the well-known algorithms.

Isotopic composition of precipitation over Arid Northwestern China and its implications for the water vapor origin

In order to reveal the characteristics and climatic controls on the stable isotopic composition of precipitation over Arid Northwestern China, eight stations have been selected from Chinese Network of Isotopes in Precipitation(CHNIP).During the year 2005 and 2006, monthly precipitation samples have been collected and analyzed for the composition of δD and δ18O.The established local meteoric water line δD=7.42δ18O+1.38, based on the 95 obtained monthly composite samples, could be treated as isotopic input function across the region.The deviations of slope and intercept from the Global Meteoric Water Line indicated the specific regional meteorological conditions.The monthly δ18O values were characterized by a positive correlation with surface air temperature(δ18O(‰) =0.33 T(℃)-13.12).The amount effect visualized during summer period(δ18O(‰) =-0.04P(mm)-3.44) though not appeared at a whole yearly-scale.Spatial distributions of δ18O have properly portrayed the atmospheric circulation background in each month over Arid Northwestern China.The quan-titative simulation of δ18O, which involved a Rayleigh fractionation and a kinetic fractionation, demonstrated that the latter one was the dominating function of condensation of raindrops.Furthermore, the raindrop suffered a re-evaporation during falling processes, and the precipitation vapor might have been mixed with a quantity of local recycled water vapor.Multiple linear regression equations and a δ18O-T relation have been gained by using meteorological parameters and δ18O data to evaluate physical controls on the long-term data.The established δ18O-T relation, which has been based on the present-day precipitation, could be considered as a first step of quantitatively reconstructing the historical environmental climate.

Visualization of flatness pattern recognition based on T-S cloud inference network

Flatness pattern recognition is the key of the flatness control. The accuracy of the present flatness pattern recognition is limited and the shape defects cannot be reflected intuitively. In order to improve it, a novel method via T-S cloud inference network optimized by genetic algorithm(GA) is proposed. T-S cloud inference network is constructed with T-S fuzzy neural network and the cloud model. So, the rapid of fuzzy logic and the uncertainty of cloud model for processing data are both taken into account. What's more, GA possesses good parallel design structure and global optimization characteristics. Compared with the simulation recognition results of traditional BP Algorithm, GA is more accurate and effective. Moreover, virtual reality technology is introduced into the field of shape control by Lab VIEW, MATLAB mixed programming. And virtual flatness pattern recognition interface is designed.Therefore, the data of engineering analysis and the actual model are combined with each other, and the shape defects could be seen more lively and intuitively.

A COM-based Framework for Management,Analysis and Visualization of Large Scope Digital Elevation Models

This paper presents a component object model (COM) based framework for managing, analyzing and visualizing massive multi-scale digital elevation models (DEMs). The framework consists of a data management component (DMC), which is based on RDBMS/ORDBMS, a data analysis component (DAC) and a data render component (DRC). DMC can manage massive multi-scale data expressed at various reference frames within a pyramid database and can support fast access to data at variable resolution. DAC integrates many useful applied analytic functions whose results can be overlaid with the 3D scene rendered by DRC. DRC provides view-dependent data paging with the support of the underlying DMC and organizes the potential visible data at different levels into rendering.

Quasi Serializable Concurrency Control in Distributed Real-Time Database Systems

This paper formally defines and analyses the new notion of correctness called quasi serializability, and then outlines corresponding concurrency control protocol QDHP for distributed real-time databases. Finally, through a series of simulation studies, it shows that using the new concurrency control protocol the performance of distributed real-time databases can be much improved.

On the Existence of an Optimal Control of Ship Automatic Steering Instruments

The existence of linear quadratic optimal control of ship automatic steering instruments is studied. Firstly, the sufficient conditions for the quadratic integrability of the solutions of linear second order time-variant differential equations are developed. Secondly, the optimal control form of the ship automatic steering instrument is obtained by using the dynamic programming method, which guarantees a minimal ship sway range, during long-distance navigation, by using as little energy as possible. Finally, based on the above mentioned sufficient conditions, the conditions for the realization of optimal control are obtained, which provides a foundation for choosing the weighted coefficients for optimal control in engineering.

Visualization Framework for Inter-Domain Access Control Policy Integration

The rapid increase in resource sharing across domains in the cloud comput- ing environment makes the task of managing inter-domain access control policy integration difficult for the security administrators. Al- though a number of policy integration and sec- urity analysis mechanisms have been devel- oped, few focus on enabling the average ad- ministrator by providing an intuitive cognitive sense about the integrated policies, which considerably undermines the usability factor. In this paper we propose a visualization flame- work for inter-domain access control policy integration, which integrates Role Based Ac- cess Control （RBAC） policies on the basis of role-mapping and then visualizes the inte- grated result. The role mapping algorithm in the framework considers the hybrid role hier- archy. It can not only satisfy the security con- straints of non-cyclic inheritance and separa- tion of duty but also make visualization easier. The framework uses role-permission trees and semantic substrates to visualize the integrated policies. Through the interactive policy query visualization, the average administrator can gain an intuitive understanding of the policy integration result.

Accelerated Particle Swarm Optimization for Controlling Virtual Power Plant Consisting of Renewable Energy Sources

RES （renewable energy sources）, such as wind and photovoltaic power plants, suffer from their stochastic nature that is why their behavior on market is very delicate. In order to diversify risk, a concept of VPP （virtual power plant） has been developed. The VPP is composed of several RES, from which at least one of them is fully controllable. Because the production of noncontrollable RES can not be forecasted perfectly, therefore an optimal dispatch schedule within VPP is needed. To address this problem, an APSO （accelerated particle swarm optimization） is used to solve the constrained optimal dispatch problem within VPP. The experimental results show that the proposed optimization method provides high quality solutions while meeting constraints.

Design Automation of the Manufacturing Process of a Mini Biodiesel Plant

The increasing pollution in the atmospheric layer has meant world-wide temperature variations, causing the melting of icecaps and floods, among other environmental factors. This change in temperature has been mainly caused by the indiscriminate emission of CO2, especially due to the rising number of vehicles in circulation. Researchers have identified that, among other types of fuel, diesel has the highest level of CO2 emission. Hence the need for the development of biodiesel, produced from oleaginous plants, aimed at reducing the emission of this harmful gas into the atmosphere, besides using renewable resources. However, as in any automation process, it is necessary to have sensors, actuators, and controllers, which together perform the automation and control of the production process. Besides that, there are other process variables to be accounted for, such as temperature, flow, and level. Considering such concept, and within the academic context, the creation process of a mini biodiesel plant will be described.

Simulation Based Synthesis, Design and Optimization of Actual Pressure Swing Adsorption （PSA） Unit

The present study demonstrates the potential of the simulation based on-line synthesis, design and optimization strategy for pressure swing adsorption （PSA） processes developed in our earlier study by implementing on an actual two-bed unit. The unit is very flexible and allows process synthesis from the PSA cycle configuration point of view. The model parameters are regressed and updated using live experimental data. The on-line monitoring and controlling of the operating parameters and operating configurations are done by multi-loop processor programmable logic controller. Separation of air into nitrogen free oxygen as raffinate stream and enriched nitrogen as extract stream using 5A zeolite as adsorbent has been chosen as a specific system for implementing the strategy. The philosophy of the typical optimization and process synthesis exercise implemented on the unit is described. The results show the successful implementation of the developed strategy on the two-bed O2-PSA unit and the application of this general approach to commercial PSA processes.

Network Reliability Analysis of Digital Instrument and Control System with GO-FLOW Methodology

In this paper,the network reliability of an actual digital instrument and control system (DICS) network is analyzed by using GO-FLOW methodology (GFM).The evaluations of common-cause failure (CCF) and uncertainty are incorporated.Three significant CCF groups (real time servers,gateways,reactor protection system) and three typical time intervals (10 min,1 h,and 24 h) are selected in the analysis.It is concluded that the network contribution of CCF accounts for over 68% of the system failure probability.The result indicates that GFM is suitable for the network reliability analysis.

Controllable synthesis of two-dimensional tungsten nitride nanosheets as electrocatalysts for oxygen reduction reaction

A facile synthetic strategy was developed for insitu preparation of two-dimensional (2D)highly crystalline tungsten nitride (WN)nanosheets with controllable morphology as oxygen reduction reaction (ORR)catalysts.The dependence of the crystal structure and morphology of WN on K2SO4content,pH,and pyrolysis temperature was thoroughly examined.The electrocatalytic performance of WN toward ORR in an alkaline electrolyte indicated that K+plays an important role in the control of size and shape in the hydrothermal and nitridation process,thereby promoting the formation of plate-like WO3and 2D WN nanosheets.The WN nanosheets,with largely exposed edge sites,provide abundant catalytic active sites and allow fast charge transfer.Furthermore,they exhibit high stability for ORR and methanol tolerance.

Impulse Observability and Impulse Controllability of Regular Degenerate Evolution Systems

Impulse observability and impulse controllability of regular degenerate evolution systems are discussed by using functional analysis and operator theory in Banach space. Necessary and sufficient conditions for the impulse observability and impulse controllability of the system are obtained. This research is theoretically important for studying the design of the degenerate evolution system.

Carbon nanotube: Controlled synthesis determines its future

Carbon nanotubes(CNTs) have received broad attention in the past decades due to their excellent physical and chemical properties and thus been regarded as a powerful candidate for future star-materials. Although various CNT products and their related applications have been demonstrated recently, their performance can hardly meet the researchers’ expectations compared with their theoretical properties. The current predicament is caused by the immature synthesis method, including the basic science and the producing technology. As the synthesis with controlled structures determines its future, this review summarizes the progress on the basic research and industrialization of CNTs in the past decades, including the fine structure control, aggregation status design and scale-up production, and further points out the way for the future development of CNTs combining with specific applications.

Periodical shedding of cloud cavitation from a single hydrofoil in high-speed cryogenic channel flow

In order to explain criteria for periodical shedding of the cloud cavitation, flow patterns of cavitation around a piano-convex hydrofoil were observed using a cryogenic cavitation tunnel of a blowdown type. Two hydrofoils of similarity of 20 and 60 mm in chord length with two test sections of 20 and 60 mm in width were prepared. Working fluids were water at ambient temperature, hot water and liquid nitrogen. The parameter range was varied between 0.3 and 1.4 for cavitation number, 9 and 17 m/sec for inlet flow velocity, and -8° and 8° for the flow incidence angle, respectively. At incidence angle 8°, that is, the convex surface being suction surface, periodical shedding of the whole cloud cavitation was observed on the convex surface under the specific condition with cavitation number and inlet flow velocity, respectively, 0.5, 9 m/sec for liquid nitrogen at 192℃ and 1.4, 11 m/sec for water at 88℃, whereas under the supercavitation condition, it was not observable. Periodical shedding of cloud cavitation occurs only in the case that there are both the adverse pressure gradient and the slow flow region on the hydrofoil.

Size and shape controllable preparation of graphene sponge by freezing, lyophilizing and reducing in container

Graphene sponge(GS) is a porous 3D structure of graphene. Although hydrothermal reduction, chemical vapor deposition, solution reduction and high temperature annealing could be used for the preparation of GS, the size and shape cannot be well controlled. Herein, we reported a facile method to prepare GS under mild condition in a size and shape controllable way. Graphene oxide was lyophilized to form the spongy structure and reduced by steamy hydrazine hydrate to produce GS. The size and shape of GS prepared were nearly identical to that of the container. The reduction degree of GS could be regulated by the reduction temperature and time.