Evaluation method for spatial straightness errors based on minimum zone condition

A new minimum zone method for evaluating straightness errors

Minimum zone evaluation of conicity error using minimum potential energy algorithms

A practical model for evaluating the calibration uncertainty of force-measuring devices is presented. The method suggests that the calibration uncertainty components of force-measuring device arise from the calibration system, force-measuring device, interaction between the calibration system and force-measuring device, and the resolution of the indicator. The basic mathematical models for uncertainty evaluation arising from the resolution of the indicator and rotation effect are proposed. The present model has been incorporated in the uncertainty evaluation of the force measurements. Some experimental results are presented to demonstrate and support the present model.

The key indicators of social effect are determined, which are the basis for the quantitative evaluation of social changes in the region, where the socio-technical project is implemented. These include raising the employment rate, improving housing provision, increasing the availability and quality of services, and increasing the availability of active and cultural recreation.The factors affecting the manageability of the socio-technical project, which should form the basis of accounting the risks of the socio-technical project are identified. These are high project risks, a high probability of project scope changes, elongated project execution phases, participation of unique resources in the project.The formation mechanism of the social effect, showing its nature is developed. This mechanism helps to understand the importance of prioritization when planning the social outcomes in the implementation of socio-technical projects. The essence of this mechanism is to transform the needs and resources into the positive and negative social effect.The model for simulating the size of the social effect, depending on the needs of a social group and the value of the project output generated in a social group is developed. This model is a graphical interpretation of the social effect formation process.The mathematical model for the quantitative evaluation of the social effect is developed. This model allows obtaining an integral indicator of social changes in the consumer's interaction with the project output. The resulting quantity is dynamic and distributed in time, its numerical value can be both positive and negative.Quantitative evaluation of the social effect of the socio-technical project allows understanding how deep changes occurred in the social life of the territory, what principles should form the basis of new management methodologies, and what results are not achieved. It should be considered that the social effect indirectly contributes to economic efficiency, since the socio-technical system usually increases the attractiveness of the territory in which it is located.

An enhanced mathematical model is introduced to study and evaluate the performance of a core node in an optical burst switched network. In the proposed model, the exact Poisson traffic arrivals to the OBS node is approximated by assuming that the maximum allowed number of arrivals to the OBS node, in a given time slot, is two (instead of infinity). A detailed state diagram is outlined to illustrate the problem, and then a mathematical model based on the equilibrium point analysis (EPA) technique is presented. The steady-state system throughput is derived from the model which is built in the absence of wavelength conversion capability. Our proposed model is aided by a simulation work which studies the performance of an OBS core node under the assumption of Poisson traffic arrivals (the exact case) and calculates the steady- state system throughput. The results obtained from the proposed mathematical model are consistent with that of simulation when assuming Poisson traffic arrivals and this consistency holds for a wide range of traffic load.

The welding volume of ship blocks plays an important role in the material supply and production management of shipyards. The traditional welding volume is estimated by empirical formula, which is easy to cause a large waste of materials and human resources when it is used to estimate the welding quantity of atypia blocks. Firstly, this paper analyzes the hull section assembly and welding process and lists the calculation formula of the cross section area of the weld deposit metal according to different section weld groove forms. And then, this paper establishes the mathematical model for the intelligent evaluation of the ship blocks welding volume. Finally, based on DELMIA, an intelligent evaluation software for the hull section welding volume is developed, which realizes the automatic recognition of the hull section weld and the intelligent evaluation of the welding volume. By comparing the calculation results of the intelligent evaluation module with the actual hull section volume data, the evaluation accuracy of this software is improved by 7.2% compared with the traditional method, and has higher stability. This evaluation software provides an accurate data basis for the reasonable allocation of welding resources, the reasonable arrangement of personnel and the reasonable formulation of production plan in the process of ship construction, and has important engineering significance.

Characterization of interaction between protein and carbohydrate using CZE

A dynamic analysis of the fluid flow and thermal behaviour of iron inside blast furnace hearth is considered. The model employs Navier Stokes two-dimensional turbulent k-ε formulation, together with corresponding energy equations, the latter considering thermal energy and permanent fluid flow equations. The differential equations are solved by means of finite element tools, with the help of ANSYS/FLOTRAN software. The obtained results allow the determination of the 1150°C isothermal, which is a crucial element for pig iron production. The results is an analysis of potential importance to the iron making industry, evolving strategies for optimising energy consumption observing the quality of the final product, refractory wear, by means of control of the process parameters.

Based on the characteristics of green appliances, the green degree evaluation index system is established from environment,resources,energy,economic,technology and society six areas. Fuzzy-EAHP applies the extension analytic hierarchy process (EAHP) to determine index weight of different levels. EAHP, which is more accurate and more objective than the traditional AHP, can quantitatively show the relative important degree between indexes with the extension interval number. Building the Mathematical model of three-lever fuzzy comprehensive evaluation, the first process comprehensive evaluation result is as input data of the latter process. At last, Fuzzy-EAHP is used to synthetically evaluate the green degree of four refrigerators. Key words: Extension analytic hierarchy process (EAHP); Green degree; Green appliance

The authors of this study propose a methodological approach to modelling the reliability evaluation of aircraft operation in combat conditions. When developing recommendations on operational and strategic requirements for promising aircraft, a very important aspect is the elicitation of the requirements for their reliability, namely no-failure operation. Reliability as a parameter of any equipment should be set in the technical specifications for development together with other operational requirements in the form of reasonable quantitative indicators – reliability standards. The establishment of specific reliability standards stimulates its growth and creates the basis for rational design, taking into account the requirements of reliable operation. The analysis showed that different models can be used to simulate aircraft reliability. In this case, for example, the final values of mean time to failure (MTTF) would be different. The test results show that the methods and mathematical models used to substantiate the values of time and probability of trouble-free operation of aircraft do not fully correspond to the actual processes of changing their state during the use in the military. This is confirmed by a significant discrepancy in the values of reliability indicators implemented in practice. This was due to the fact that the acquainted mathematical models of aircraft reliability do not take into account the combat conditions in which they are supposed to operate. In addition, the reliability indicators used do not take into account possible changes (decrease) in these indicators during the period of aircraft operation. In general, the shortcomings inherent in the methods and mathematical models currently used to describe the aircraft reliability reduce the accuracy of the results obtained, and also do not quite adequately reflect the features of the corresponding process. When using different models, the cost of time to failure differs significantly. The more factors are taken into account, the greater the operating time to failure will be. This means that when designing aircraft, it is necessary to set the value of this indicator greater than indicated in the form. Taking into account additional factors complicates the model, but at the same time makes it more accurate.

We found that the electrical equipment has a dynamics of failure rate growth according to the results of the processing of the statistical information of electric transport enterprises and analysis of the operating conditions of rolling stock systems and aggregates. We established that traction electric motor failures make up 20 % of all failures of electrical equipment. We analyzed the conditions of operation of traction electric motors and estimated the reliability. The study of probabilistic and statistical characteristics of the functions of the distribution density of traction electric motors failure shows that some failures are approximated by an asymmetric distribution. In this regard, it is advisable to use a truncated normal distribution function N N{t; T; }, which will make possible tp increase the adequacy of models. We established that the number of failures in the interval 0-t1 decreases significantly for large probability Q. We can consider the flow of failures in this interval as stationary for certain values. We proposed a mathematical model for reliability evaluation (14), which, unlike existing models, is based on the system analysis of the probabilities of failure of subsystems, which are subjected to diagnosis (brush-holding unit, stator, anchor, collector), on a base of structural and functional diagrams of traction electric motor elements. It makes possible to determine parameters of various elements of traction electric motors during operation. The model differs qualitatively from the existing ones by taking into account structural and electromagnetic characteristics and gibes possibility to optimize parameters of different units in relation to the requirements of the system of planned and preventive repair, when traction motors developed a given resource and continue to operate. Thus, it is possible to estimate reliability parameters a traction electric motor of any type according to the results of the studies and the above calculations.

Based on a comparative analysis of the definitions of reliability and resistance, the article substantiates the possibility of using the probability of failure of radio-electronic equipment of an information system (REA IS) as an indicator of resistance to the effects of EMR. The interrelation of these definitions is shown and an analytical model is proposed for assessing the stability of equipment to the effects of a sequence of electromagnetic radiation. As an indicator of resistance, it is proposed to use the probability of failure of the REA during operation.

The construction of professional dynamic adjustment early warning evaluation model in higher vocational colleges is the need to promote and improve the construction and management of the national "double high plan", the need to complete the construction objectives and tasks of the "double high plan" with high quality, and the practical need to innovate and enrich the performance index evaluation system of higher vocational colleges. Based on AHP analytic hierarchy process, this paper designs the mathematical model of dynamic adjustment and early warning evaluation of Higher Vocational Majors, which is monitored from six first-class indicators: student source and scale, school enterprise cooperation, professional teaching guarantee conditions, professional teaching and construction, scientific research and social services, training quality and social reputation, and calculates the comprehensive ranking of Majors Based on the data of higher vocational talent training status, which is an important basis for professional dynamic adjustment. The model is used to measure the specialty of Chengdu Vocational and technical college. The calculation results are consistent with the actual situation of the University, which proves that the evaluation model is effective and can be popularized.

Power supply enterprises for avoiding the customer credit risks which exist in management, should establish the analysis model of customer credit risk analysis model, carries on the effective appraisal to the customer credit risks. This article used AHP to determine each evaluating indicator's weight in the customer risk, used the method of the fuzzy quality synthetic evaluation to carry on risk assessment. The combination of the analytic hierarchy process and fuzzy comprehensive evaluation establishes the mathematical model of fuzzy comprehensive evaluation about risk real estate development, which offers a combination of qualitative and quantitative analysis for the assessment of customer credit risks.

Since the dose delivery pattern is different between intensity-modulated radiotherapy (IMRT) and conventional radiation, radiobiological assessment of the physical dose delivered by IMRT is considered necessary. In IMRT, the daily dose is usually given intermittently over a time longer than that used in conventional radiotherapy. During prolonged radiation delivery, sublethal damage repair takes place, leading to the decreased effect of radiation. This phenomenon is universarily observed in vitro. In in vivo tumors, however, this decrease in effect may be counterbalanced by rapid reoxygenation; we demonstrated it in murine tumors. Studies on reoxygenation in human tumors are warranted to better evaluate the influence of prolonged radiation delivery. Another issue related to high-dose-per-fraction intensity-modulated stereotactic radiotherapy is the mathematical model for dose evaluation and conversion. Many clinicians use the linear–quadratic (LQ) model and biologically effective dose (BED) to estimate the effects of various radiation schedules, but it has been suggested that the LQ model is not applicable to high doses per fraction. Recent experimental studies verified the inadequacy of the LQ model in converting hypofractionated doses into single doses. The LQ model overestimates the effect of high fractional doses of radiation. BED is particularly incorrect when it is used for tumor responses in vivo, since it does not take reoxygenation into account. For normal tissue responses, improved models have been proposed, but, for in vivo tumor responses, the currently available models are not satisfactory, and better ones should be proposed in future studies.