酒钢皮带秤自动分料计量的实现

本文介绍一台皮带秤称不同的物料时如何进行自动分料计量。详细说明自动分料计量中用AB contrologix 5000的实现方法,控件技术在上位监控画面的应用以及计量数据网络发布的实现等。

油脂集中润滑系统的原理与维修

阐述加压式油脂集中润滑系统的特点与原理,总结某类高速桥式铣床导轨润滑系统的维修方法,并改进润滑系统与相关的PLC控制程序。

Design of new biomedical titanium alloy based on d-electron alloy design theory and JMatPro software

A new kind offl biomedical titanium alloy, Ti-35Nb-4Sn-6Mo-9Zr, composed of non-toxic elements Nb, Mo, Zr and Sn with lower elastic modulus and higher strength was designed based on d-electron alloy design theory and JMatPro software using orthogonal experiment. The microstructure and basic mechanical properties of designed alloy were investigated. The results show that the alloy is composed of single fl equiaxed grains after solution treatment at 800 ~C. Compared with Ti-6A1-4V, the mechanical properties of the designed alloy are more excellent： E=65 GPa, σb=834 MPa, σ0.2=802 MPa, and σ=11%, which is expected to become a promising new type implanted material. The research approach adopted can reduce the experimental time and cost effectively, and get the ideal experimental results.

外圆磨床导轨润滑系统的设计优化

介绍了最大磨削直径为Φ320mm及以下规格外圆磨床的常用导轨润滑模式,对现有同时使用两种不同形式导轨的磨床润滑系统做优化,使其润滑模式更统一,并能满足同规格不同磨削长度的需求。同时通过合理的需油量计算及润滑元件选择,优化系统油箱参数。

Research of NS dataflow mechanism and its analyzer implementation

This paper analyzes the main elements in NS network simulator, makes adetailed view of dataflow management in a link, a node, and an agent, respectively, and introducesthe information described by its trace file. Based on the analysis of transportation and treatmentof different packets in NS, a dataflow state machine is proposed with its states exchange triggeringevents and a dataflow analyzer is designed and implemented according to it. As the machine statefunctions, the analyzer can make statistic of total transportation flux of a specified dataflow andoffer a general fluctuation diagram. Finally, a concrete example is used to test its performance.

A novel adaptive classification scheme for digital modulations in satellite communication

To make the modulation classification system more suitable for signals in a wide range of signal to noise ratios （SNRs）, a novel adaptive modulation classification scheme is presented in this paper. Differ-ent from traditional schemes, the proposed scheme employs a new SNR estimation algorithm for small samples before modulation classification, which makes the modulation classifier work adaptively according to estimated SNRs. Furthermore, it uses three efficient features and support vector machines （SVM） in modulation classification. Computer simulation shows that the scheme can adaptively classify ten digital modulation types （i.e. 2ASK, 4ASK, 2FSK, 4FSK, 2PSK, 4PSK, 16QAM, TFM, π/4QPSK and OQPSK） at SNRS ranging from 0dB to 25dB and success rates are over 95% when SNR is not lower than 3dB. Accuracy, efficiency and simplicity of the proposed scheme are obviously improved, which make it more adaptive to engineering applications.

Application of empirical mode decomposition based energy ratio to vortex flowmeter state diagnosis

To improve the measurement performance, a method for diagnosing the state of vortex flowmeter under various flow conditions was presented. The raw sensor signal of the vortex flowmeter was adaptively decomposed into intrinsic mode functions using the empirical mode decomposition approach. Based on the empirical mode decomposition results, the energy of each intrinsic mode function was extracted, and the vortex energy ratio was proposed to analyze how the perturbation in the flow affected the measurement performance of the vortex flowmeter. The relationship between the vortex energy ratio of the signal and the flow condition was established. The results show that the vortex energy ratio is sensitive to the flow condition and ideal for the characterization of the vortex flowmeter signal. Moreover, the vortex energy ratio under normal flow condition is greater than 80%, which can be adopted as an indicator to diagnose the state of a vortex flowmeter.

Optimum control strategy for all-variable speed chiller plant

The optimum control strategy and the saving potential of all variable chiller plant under the conditions of changing building cooling load and cooling water supply temperature were investigated. Based on a simulation model of water source chiller plant established in dynamic transient simulation program (TRNSYS),the four-variable quadratic orthogonal regression experiments were carried out by taking cooling load,cooling water supply temperature,cooling water flow rate and chilled water flow rate as variables,and the fitting formulas expressing the relationships between the total energy consumption of chiller plant with the four selected parameters was obtained. With the SAS statistical software and MATHEMATICA mathematical software,the optimal chilled water flow rate and cooling water flow rate which result in the minimum total energy consumption were determined under continuously varying cooling load and cooling water supply temperature. With regard to a chiller plant serving an office building in Shanghai,the total energy consumptions under different control strategies were computed in terms of the forecasting function of cooling load and water source temperature. The results show that applying the optimal control strategy to the chiller plant can bring a saving of 23.27% in power compared with the corresponding conventional variable speed plant,indicating that the optimal control strategy can improve the energy efficiency of chiller plant.

Harmful algal blooms and eutrophication: "strategies" for nutrient uptake and growth outside the Redfield comfort zone

While many harmful algal blooms have been associated with increasing eutrophication, not all species respond similarly and the increasing challenge, especially for resource managers, is to determine which blooms are related to eutrophication and to understand why particular species proliferate under specific nutrient conditions. The overall goal of this brief review is to describe why nutrient loads are not changing in stoichiometric proportion to the "Redfield ratio", and why this has important consequences for algal growth. Many types of harmful algae appear to be able to thrive, and/or increase their production of toxins, when nutrient loads are not in proportion classically identified as Redfield ratios. Here we also describe some of the physiological mechanisms of different species to take up nutrients and to thrive under conditions of nutrient imbalance.

Spatial Process of Green Infrastructure Changes Associated with Rapid Urbanization in Shenzhen,China

Through a case study of Shenzhen City,China,this study focused on a quantitative method for analyzing the spatial processes involved in green infrastructure changes associated with rapid urbanization.Based on RS,GIS and SPSS statistics software,the approach includes selection of the square analysis units and representative landscape metrics,quantification of the change types of landscape metrics in all analysis units through two indices and hierarchical cluster analysis of the above analysis units with different landscape metric change types(i.e.spatial attributes).The analyses verify that there is a significant sequence of continuous changes in green infrastructure in Shenzhen.They are the perforation,the segmentation,the fragmentation,the evanescence and the filling-in processes,which have a good spatio-temporal correspondence with urbanization and reflect the synthetic influence of urban planning,government policies and landforms.Compared with other studies on quantifying the spatial pattern,this study provides an alternative probe into linking the spatial pattern to spatial processes and the corresponding ecological processes in the future.These spatio-temporal processes offer many opportunities for identifying,protecting and restoring key elements in an urban green infrastructure network for areas in the early stages of urbanization or for non-urbanized areas.

Using Energy Conditions to Distinguish Brane Models and Study Brane Matter

Current universe （assumed here to be normal matter on the brahe） is pressureless from observations. In this case the energy condition is po ≥ 0 and po =O. By using this condition, brahe models can be distinguished. Then, assuming arbitrary component of matter in DGP model, we use four known energy conditions to study the matter on the brahe. If there is nonnormal matter or energy （for example dark energy with w 〈-1/3） on the brane, the universe is accelerated.

A Study on Simple Prediction Method of Heat Load： A Use of Linear Approximation Indicial Response in Basements

This study was conducted to establish a predictable method for a heat load of an underground structure with sufficient accuracy. As the first step, our previous paper reported the measurement results of field experiments on an underground experimental basement under internal heat generation conditions. Also, it presented the results of numerical analyses on the heat and moisture behavior and the influence of internal heat generation of the experimental basement and ground. However, it is practically impossible to utilize the model of simultaneous heat and moisture transfer at the design phase because the prediction by the model of simultaneous heat and moisture transfer requires a long calculation time. In this paper, the authors present the simple load calculation technique, using a linearized approximation indicial response of the inner surface heat flux in a basement to outdoor air temperature change. In addition, the approximation indicial responses for each part of the single-walled concrete drawn using this technique are arranged. The heat load calculation example of application to the basement of the optional size by this technique is shown.

Design of Finite Element Tools for Coupled Surface and Volume Meshes

Many problems with underlying variational structure involve a coupling of volume with surface effects.A straight-forward approach in a finite element discretiza- tion is to make use of the surface triangulation that is naturally induced by the volume triangulation.In an adaptive method one wants to facilitate'matching'local mesh modifications,i.e.,local refinement and/or coarsening,of volume and surface mesh with standard tools such that the surface grid is always induced by the volume grid. We describe the concepts behind this approach for bisectional refinement and describe new tools incorporated in the finite element toolbox ALBERTA.We also present several important applications of the mesh coupling.

Study on the Injection Molding and Optimization of Radiator Cap based on CAE Technology

In order to improve the radiator cap of the automobile cover forming quality and efficiency, this paper applies the UG software to carry out the design of the injection mold, and use Moldflow software to simulate and analyze the position of gate filling, flow, cooling and other aspects of application, to determine the best inject location and optimize die structure design. The research results show that the combination of CAD and CAE technology can effectively improve the mold design quality, shorten die development cycle, and reduce the cost of development.

Linear Optical Scheme for Implementing Optimal Real State Cloning

We propose an experimental scheme for implementing the optimal 1 → 3 real state cloning via linear optical elements. This method relies on one polarized qubit and two location qubits and is feasible with current experimental technology.

A two-phase system call arguments attribute analyzing method

To detect more attacks aiming at key security data in program behavior-based anomaly detection,the data flow properties were formulated as unary and binary relations on system call arguments.A new method named two-phrase analysis(2PA)is designed to analyze the efficient relation dependency,and its description as well as advantages are discussed.During the phase of static analysis,a dependency graph was constructed according to the program's data dependency graph,which was used in the phase of dynamic learning to learn specified binary relations.The constructed dependency graph only stores the information of related arguments and events,thus improves the efficiency of the learning algorithm and reduces the size of learned relation dependencies.Performance evaluations show that the new method is more efficient than existing methods.

Housing Correlates of Under-Five Mortality in Urban Ethiopia

Little studies and analysis have been undertaken to investigate the housing determinants of under-five mortality in Ethiopia. This study, therefore, explores the impacts of urban housing variables on the levels and patterns of under-five mortality in the country based on the SPSS （Statistic Package for Social Science） file of the 2005 Ethiopian Demographic and Health Survey （EDHS）. This survey covered a sample of about 4,420 households/housing units of urban Ethiopia. The under-five deaths are computed for women in the age group 15-49 by subtracting the number of children living from children ever born （CEB） and established the proportion dead by dividing deaths by CEB corresponding to the categorical variables of housing structure, facilities, and household durables. The analytical techniques of the study included univariate, bivariate, and multivariate data analysis of the proportional variations of childhood mortality patterns being manifested by ＂bar graphs＂ with respect to housing situations as well as household durables. Amongst the categorical variables of the housing structures, facilities, and household durables with the highest no prevalence of under-five mortality levels are found to be the units of unconventional walls, thatched/leaf/reed roofing, animal dung flooring, shared pit latrine/use of bucket/bush, using kerosene, firewood/straw/charcoal for cooking, unconventional lighting, unprotected water supply, households with no durables.

Effect of Rootstocks on Growth, Yield and Bean Quality of Coffea canephora Clones

Coffee cultivation on dry area lately faces more often drought condition because of global warming effect. One effort to solve the problem is by using tolerant clones or varieties as the rootstocks. The aim of this research is to observe influence of BP 308, BP 409, and Exelsa as rootstocks, on growth, yield and bean quality of BP 409, BP 534, BP 936 and BP 939 clones as scions. The research was conducted in Temanggung district of Central Java, Indonesia, using randomized complete block design with 5 replications 10 plants per replication. The result showed that rootstock influenced stem height and number of branches, leaf relative water content （RWC） during dry season, but not stem diameter. BP 308 and BP 409 rootstocks supplied water more than Exelsa, it seem RWC scion on both rootstocks were higher （82.0%） than that of Exelsa （80.0%）. Exelsa rootstock cause scion grow more slowly, so bean yield was lower than on BP 308 and BP 409. Yield accumulation until 4 years old on Exelsa was 55% to BP 308, and 52.2% to BP 409 rootstock. Yield of BP 939/BP 308 and BP 409/BP 409 （scion/rootstock） tend to the highest. Rootstocks did not influence percentage of normal and abnormal beans and the outturns. Bean outturn was more influenced by clones. Exelsa rootstock improves caffeine content, body, astringent and bitterness characters of scion cherries, but decreases fragrance and aroma characters of scion yield. It is concluded that farther taxonomical relationship of rootstock, their influence on scion growth, yield and cup test characters are stronger.

Calibrations of Amber Perspex-PMMA Dosimeter in the CDTN Gamma Irradiator Operational Conditions

This paper presents results of PMMA （polymethylmethacrylate） dosimeters calibrations that are used as routine dosimeters in CDTN （Nuclear Technology Development Center） Gamma Irradiation Laboratory. The study was carried out within the framework of the Facility Quality Assurance Program with the purpose of to determine the calibration curve and accuracy of the Harwell Amber Perspex 3042 W dosimeters. The irradiations of the dosimeters were made in operational conditions of a Gamma lrradiator at CDTN, an R ＆ D （research and development） institute connected to the CNEN （National Nuclear Energy Commission） （Brazil）. The values for estimate of the expanded uncertainties achieved are typical of a routine dosimetry system.

Impact of Risk on Performance of Design and Build Projects in Lagos State, Nigeria

＂Design and Build＂ procurement method has been in use in Nigeria and this method has been latent with a lot of risks. This study intends to identify the risk inherent in ＂Design and Build＂ and also to evaluate the impact of the identified risks on project performance. A descriptive research survey is undertaken for this study. Snowballing sampling technique was used via the use of questionnaires. Population of the study includes contracting organizations, consultants and clients＇ organizations that are recently involved in ＂Design and Build＂ projects. A total of 39 questionnaires were distributed and 27 were returned and used for the analysis. Statistical Package for Social Sciences was used for analyzing the data collected. Descriptive statistical tool of mean item score was employed for the analysis. The results show that the most prominent risk is change in quantity/scope of work in terms of cost related risk while in terms of time related risks the most prominent risk is design changes. Errors and omissions during construction are the risks prominent in terms of quality. In conclusion, ＂Design and Build＂ procurement has a lot of inherent, unresolved and undefined cost, time and quality related factors that can trigger off risks that will affect performance of DB project. Implications of this study to practitioners in the construction is such that the findings of this study can create awareness for stakeholders and construction practitioners of the prominent risks that affect DB projects and this can help in better management of future DB projects in Nigeria and other developing countries. Design and Build procurement in spite of these plethora of risks is still strongly recommended for clients, stakeholders and other practitioners in the construction industry for use in their future projects. This procurement method delivers project faster, within cost and offers good quality of workmanship and product to users of this method.