装配型企业面向产品CAPP系统中关键技术研究与实现

以装配型企业为研究对象,研究了装配型企业面向产品CAPP系统的几个关键技术和实现方法。为构建一个具有开放性、适用性、分层递阶的装配型企业CAPP与工艺信息管理应用系统铺平了道路。     

装配型企业面向产品CAPP系统体系结构的研究

以装配型企业为研究对象，提出并研究了装配型企业面向产品CAPP系统体系结构、功能模型、信息模型；构建一个具有开放性、适用性、分层递阶的装配型企业CAPP与工艺信息管理应用系统，以提高装配型企业工艺设计及工艺信息管理水平和企业竞争力。     

项目驱动型制造企业信息化需求特点分析

越来越多的企业开始采取项目驱动型管理模式,以满足客户日益提高的个性化需求.相应的,该类企业的特点对其信息化建设提出了新的要求.研究首先从项目驱动型与作业驱动型制造企业的区别入手,探讨了项目驱动型制造企业信息化建设的任务;然后,基于项目驱动型制造企业的基本作业链和基本业务逻辑过程,总结了该类企业对信息化建设的需求.     

项目驱动型制造企业信息化需求特点分析

越来越多的企业开始采取项目驱动型管理模式,以满足客户日益提高的个性化需求。相应的,该类企业的特点对其信息化建设提出了新的要求。研究首先从项目驱动型与作业驱动型制造企业的区别入手,探讨了项目驱动型制造企业信息化建设的任务;然后,基于项目驱动型制造企业的基本作业链和基本业务逻辑过程,总结了该类企业对信息化建设的需求。     

行业型企业联盟的信息化研究与实践

Ｉｎｔｅｒｎｅｔ技术对生产方式最大的影响是促进了企业的各种联盟。行业型企业联盟有着其重要的特点,本文在对行业型企业联盟信息建模的基础上,分析讨论行业型企业联盟信息化建设的方式、方法及其具体表现形式,并针对流体动力领域的信息化建设,进行了应用研究。     

以信息网络为核心的行业型企业联盟

】Ｉｎｔｅｒｎｅｔ 技术的发展，促进了企业的各种联盟。本文通过对各种企业联盟的分析研究，提出要对基于行业的企业联盟方式进行研究。并以信息技术为基础，对行业型企业联盟的现代化改造，开展信息建模研究以及行业型企业联盟的关键技术－ － 行业信息网络的实现方法的研究     

现代制造型企业装配过程质量管理方案的探究

伴随着生产力水平和科学技术水平的提高,制造型企业装配过程中的控制因素更加复杂和多变,这使得研究现代制造型企业装配过程的质量管理方案迫在眉睫.在阐述现代制造型企业过程质量管理新理念的基础上,就其如何实施装配过程质量管理,提出了几点自己的看法和建议.     

产业补贴模式下的制造企业低碳生产行为选择

为研究政府低碳产业补贴对处于不同市场地位的制造商低碳生产决策的影响,考察由领导型制造企业和追随型制造企业组成的双寡头市场,构建了双方的Stackelberg博弈模型。研究发现:补贴政策对不同企业低碳生产行为的激励效果不同,当补贴力度达到某一阈值后,领导型企业率先选择低碳生产,随着补贴力度的进一步提高,追随型企业也将选择低碳生产;当企业面临较高的低碳产品生产成本和较低的消费者低碳偏好时,政府应该给予低碳企业较高的补贴;实现社会福利最大化的低碳补贴政策与消费者低碳偏好负相关,而与低碳产品减排标准、低碳产品环境效益、政府对环境的重视程度等因素正相关。     

基于Web本体语言的横向型企业集群生产能力建模

在研究企业能力的基础上,提出一种基于本体的横向型企业集群生产能力的表示方法,从概念、概念的基本属性和关联属性三个方面建立横向型企业集群生产能力的本体语义模型,使用最新的Web本体建模语言OWL建立横向型企业集群生产能力本体。实例应用表明,该方法能完整地勾勒出横向型企业集群的生产能力。     

用于行业型企业联盟的公共数据中心的研究

行业型企业联盟的建立是我国国有企业进行信息化改造的重要突破口之一。在行业型企业信息网需求分析的基础上 ,研究行业公共数据中心的逻辑结构和关键技术 ,并针对机床行业公共数据中心进行了应用开发 ,有利于行业信息化的发展     

EXPERIMENTAL RESEARCH AND DESIGN ON HEAT TRANSFER OF EVAPORATOR USED IN THE LARGE QUICK FREEZE PLANT

The evaporator is the main part of a quick-freeze equipment. There are many factors influencing the heat transfer coefficient of an evaporator. The most important factors among them are the fin shape, tube diameter, distance of fin space, frost, and velocity of air flow etc. They mainly influence the thermal efficiency of an evaporator, and therefore its thermal efficiency has direct relationship with the whole efficiency of the quick freeze plant. Evaporators with different structural types have different heat transfer efficiency. In order to obtain high efficiency structure of evaporator, 8 evaporator models with different fin shape, tube diameter and tube arrangement are analyzed and compared. The calculation results show that the integral waved fins, equilateral-triangle arranged small diameter tubes and varying fin-spacing has the highest heat transfer coefficient. The experimental result also shows that the evaporator with this type of structure has better thermal efficiency. The experimental result is in good agreement with the calculation result. It can instruct engineering design for usual designer. A real quick-freeze equipment is designed and put into production. The result shows that, compared with traditional domestic quick-freeze equipments, this equipment decreases by 40% in size and by 20% in energy consumption.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

The use of chemiluminescence in determining the thermal and oxidative stability of motor oils

Chemiluminescence is reviewed as a method of characterising different behaviour of lubricating oils. This includes mineral oils containing additives such as zinc dialkyl-dithiophosphates, sulphonates, succinamides. alkylphenols and polymers. Using a chemiluminescence apparatus and manometric apparatus, various lubricant oil fractions blended with additives were examined. The basic emitters of chemiluminescence are excited carbonyl compounds, and results are presented showing the measurement of chemiluminescence at elevated temperatures.     

GENERATE ROUGH TOOL-PATHS FROM UNORGANIZED POINT-CLOUD DIRECTLY

An approach is presented to generate rough interference-free tool-paths directly from massive unorganized data in rough machining that is performed by machining volumes of material in a slice-by-slice manner. Unorganized point-cloud is firstly converted to cross-section data. Then a robust data-structure named tool-path net is constructed to save tool-path data. Optimal algorithms for partitioning sub-cut-areas and computing interference-free cutter-locations are put forward. Finally the tool-paths are linked in a zigzag milling mode, which can be transformed into a traveling sales man problem. The experiment indicates optimal tool paths can be acquired, and high computation efficiency can be obtained and interference can be avoided successfully.     

PHENOMENON OF CARVED DRIVING WHEELS

A newly found phenomenon of carved driving wheels of a rear-wheel-drive tractor used in an airport is discussed. The circum of every driving wheel is damaged at three regions,which distribute regularly and uniformly. Everyday,the tractor tows a trailer which are times heavier than the tractor,and moves on the same road in the airport. The phenomenon is explained by the torsional self-excited vibration system of the powertrain. The simplified torsional vibration system is discribed by a 2-order ordinary differential equation,which has a limit circle. Experiments and numerical simulations show the followings: Because of the heavy trailer,the slip ratio of the tractor’s driving wheels is very large. Therefore,there is severe torsional self-excited vibration in the tractor’s drivetrain,and the self-excited vibration results in severe and regular fluctuations of the rear wheel’s velocity. The severe fluctuations in velocity fastens the damage of the driving wheels. At the same time,the time interval in which an arbitrary point in the circum of the driving wheel contacts with the road twice is two times more than the period of the torsional self-excited vibration,and this times explained the existence of three damaged regions. At last,it points out that the phenomenon can be avoided when the torsional damping is large enough.     

Stromules and the dynamic nature of plastid morphology

Investigation of plastids via green fluorescent protein (GFP) has led to the rediscovery of tubular extensions of the plastid membrane, termed stromules, for stroma‐filled tubules. These unique structures are challenging our understanding of plastid structure and function. Stromules are highly dynamic, branching and elongating across the plant cell. Recent experiments indicate that cytoplasmic microtubules and microfilaments control the shape and motility of stromules. Whether stromule formation involves plastid‐specific structural systems, such as the plastid division machinery, remains open to debate. Fluorescence photobleaching experiments have revealed that GFP can traffic between plastids joined by stromules. As a result, interest has grown in whether other macromolecules can also travel through these connections. Although the function of stromules is unknown, several aspects of their biology suggest they play a role in molecular exchange between plastids and other organelles.     

A microscope diffusion chamber for the determination of the equilibrium and non-equilibrium osmotic response of individual cells

A microscope diffusion chamber has been developed which allows direct observation of the dynamic osmotic response of individual cells in micro-volume suspensions. Continuous observation of stationary cells is possible including short experimental times while the extracellular chemical composition is changed. Multiple changes of solute type or concentration are easily imposed upon a single sample volume. Response times are a function of chamber configuration but response times as low as 1–10 s are possible with negligible solute concentration gradients within the sample region. The chamber is simple and economical to construct and use. It is the size of an ordinary glass microslide and it can be adapted easily to any common laboratory microscope. All standard optical techniques may be used with the chamber. Construction details and operating characteristics including important limitations are discussed. Example photomicrographs and osmotic data are included.     

VOLUME DEFECT FATIGUE FAILURE OF CERAMIC BALLS UNDER ROLLING CONDITION

A newly developed pure rolling fatigue test rig with three contact points is used to test the rolling contact fatigue properties of silicon nitride ceramic balls. Ball surfaces are examined after failure with optical microscopy and scanning electron microscopy. The failure cause,fatigue phenomenon and mechanics are analyzed. The research shows that subsurface cracks play a dominant role in the formation of spalling failure. These cracks originated from volume defects of the material and propagate,to form elliptical fatigue spalls under the action of principal tensile stresses. The principal tensile stress increases with increasing contact load,causing spall formation and reduction of rolling contact life. The greater the principal tensile stress is,the more severe the peeling of near surface is. Under the same condition,the closer volume defects are to the surface,the more likely failure occurs,the shorter the rolling contact life is.     

气化炉三维扫描测量与数据处理

以德士古气化炉耐火砖的内壁蚀损检测设备为基础,对采集到的点云数据做了进一步处理.通过对数据的筛选和剔除,实现了数据点的平滑降噪细化和精简.然后利用点云对整、网格划分和分色显示等方法,最终完成了内壁腐蚀情况的三维建模.重点讨论了点云数据的预处理及后处理的方法,并根据内壁耐火砖的腐蚀阈值,提出了一种气化炉内壁腐蚀区域的识别与分割方法.对耐火砖的腐蚀分析、气化炉的生产与维修提供了可靠依据,并在工程应用中获得了一致认可.     

Multiple-tapped-delay-line hardware-linearisation technique based on wire load regulation

This article describes designing, implementation and tuning processes of multiple-tapped-delay-line (MTDL). Obtained MTDL can be implemented in various field-programmable-logic-devices (FPGA) devices and applied for time-to-digital-converters (TDC) construction. The task of tuning process is the tapped-delay-line (TDL) linearisation, and consists of two stages. The first stage depends on selecting an appropriate configurable-logic-block (CLB) for particular delay-segment realization and selecting proper connection between these blocks. The second tuning stage, that is essential from this article viewpoint, depends on inter CLBs connecting wires delay regulation realized directly by load regulation. The Load regulation depends on connecting an appropriate number of unused three-state-buffers or CLB inputs to the wire which delay is adjusted. Depending on the number of inputs connected to the wire its capacitance changes that influences its time-constant and finally changes its time-delay.The MTDL mathematical model, obtained characteristics and results of time-interval (TI) measurements are also presented. The derived TDL model provides information about how the particular wire delay should be changed and in which order the changes should be executed. This makes the designing process predictable and easy to carry out. Presented characteristics confirm the proper operation of presented linearisation technique. The proper operation of the whole measuring module is confirmed by obtained TIs histograms presentation.