Determination of the efficiency of a multiple launch rocket system

Up-to-date multiple launch rocket systems (MLRSs) are adopted by many countries of the world, and they are an effective weapon against dispersed multiple targets. Developing and upgrading MLRSs calls for estimating their efficiency with the aim to select an optimum alternative. For an MLRS, the basic measure of area target destruction efficiency is the relative damage area. This measure depends on the damage area of the MLRS itself (extent of damage by one salvo). The paper suggests a relative criterion that allow one to estimate and optimize the salvo damage area. The criterion is based on the ratio of the salvo damage area to the maximum damage area and that of the undamaged area to the coverage area. The coverage area is defined as the area of the enveloping convex polygon for all points of missile impact in a salvo. It is shown that the domain of variation of the suggested criterion is the interval [0, 1]. Using the suggested criterion for 4 points of missile impact with a circular damage area, two basic structures are studied: a rhomb (two regular triangles) and a square. For them, optimum distances between the missile impact points that maximize the destruction level are determined. It is shown that the obtained optimum arrangement of missile impact points allows one to bring the extent of damage for the square structure to the more optimum rhomb layout (represents a part of the hexagonal structure, which is the most efficient from the standpoint of the packing problem). For a 16-missile salvo, it is shown that from the standpoint of the suggested criterion there exists an optimum relation between the missile damage area (radius) and the technical scattering parameters. The maximum value of the criterion for a missile salvo with account for the technical spread does not exceed 0.33 and is much lower than the value that can be obtained for the optimum structures (rhomb and square). The paper shows possibilities of using the criterion in deciding on optimum missile impact points with account for various typical targets within a multiple target and missile damage area configurations other than a circle.

The Significance of Extra-Cage Bridging Bone via Radiographic Lumbar Interbody Fusion Criterion

Study Design: Prospective observational study. Objectives: We aimed to analysis the distributional patterns of the intra- and extra-cage bridging bone (InCBB and ExCBB) and the significance of ExCBB using suggested lumbar interbody fusion criterion. Methods: This study included the patients with planned single-level transforaminal lumbar interbody fusion. We divided bridging bone into InCBB (in void of right or left cage) and ExCBB (outside of cages; anterior, posterior, intermediate, right, or left) and graded bridging scores from 0 to 2 on postoperative 1-year computed tomography. The fusion was defined as at least having one or more graded 2 and the evaluation were conducted twice by 2 raters. Results: Sixty-five patients were enrolled. All values of intra- and inter-rater reliability in left InCBB, anterior, and posterior ExCBB showed good agreements (≥0.75). Both InCBBs showed similar mean bridging scores (Rt:1.43 vs Lt:1.48), and in ExCBBs, the anterior was the highest (1.43), followed by the posterior (1.14); the right and left were the lowest (0.49 and 0.52 respectively). In subjects determined as fusion (85.4%), complete bridging was observed more in ExCBB (88.8%) than in InCBB (69.9%). Conclusions: Given the higher bridging scores in both InCBBs and Ant. ExCBB, bone grafting is important promoting factor to increase the interbody bridging bone regardless of outside or in void of cages. Based on our suggested criterion, ExCBB has a greater proportion compared to InCBBs for determining the fusion and extra-cage bone grafting should be considered as important procedures for interbody fusion.

Structural failure criterion for spatially-reinforced carbon-carbon composite materials

This paper defines the structural strength criterion for 4DL-reinforced carbon-carbon materials. For this scheme, fiber reinforcement consists of four groups of reinforcing elements, three of them are located in parallel planes with the angles of 120° between them and the fourth one is normal to them. The paper addresses the first failure of the material corresponding to its yield stress, in this point, one of the material components deviates from linear elastic behavior. A composite material is considered to be non-uniform structurally and consists of a matrix and reinforcing elements, rods. Those rods, in their turn, represent a unidirectional composite. To analyze the stress-strain state of individual components of the material, a three-level elastic model is built that uses the analytic approach at the micro level, while at higher levels it uses the finite element method. For numerical calculations, a structural cell of the material is taken. The boundary conditions provide small to negligible influence of the edge effects, thus simulating the behavior of the infinite volume of the material. For the material components, local strength criteria are introduced, where the fields of the criterion quantities are averaged over the volume of the structural cell. The strength surface of the material that corresponds to its first failure is obtained, and the conclusion is made that the suggested criterion provides a reasonable agreement with the available data on the typical carbon-carbon composite characteristics. Based on the calculated dependencies of the material’s yield stress on the load direction, a procedure is suggested to identify the model parameters based on the material failure behavior analysis using standard tensile and compressive tests. Estimated discrepancies between the results calculated using the suggested criterion and those obtained using the limiting stress criterion for biaxial stress states are given. It is shown that the discrepancy may reach tens of percent and in some cases the material strength increases in comparison with that in the uniaxial stress state. The results are subject to verification tests in order to verify the model for advanced spatially reinforced carbon-carbon composite materials.

Control of the degradation of the mineral transformer oils hydrocarbon base

Currently, the degree of degradation of the oils hydrocarbon base remains outside the field of vision of operating services. The aim of this work was to analyse the process of regeneration of aged mineral transformer oils using adsorption cleaning. IR spectroscopy shows that the hydrocarbon composition of oils undergoes changes during operation. And those changes are cannot be restored. We propose the concept for the control of destruction degree of the mineral oils hydrocarbon base. The suggested criterion based on the IR method may be used when decision is making whether the transformer oil should be replaced with a new one.

Information Theoretic Multi-Target Feature Selection via Output Space Quantization

A key challenge in information theoretic feature selection is to estimate mutual information expressions that capture three desirable terms—the relevancy of a feature with the output, the redundancy and the complementarity between groups of features. The challenge becomes more pronounced in multi-target problems, where the output space is multi-dimensional. Our work presents an algorithm that captures these three desirable terms and is suitable for the well-known multi-target prediction settings of multi-label/dimensional classification and multivariate regression. We achieve this by combining two ideas—deriving low-order information theoretic approximations for the input space and using quantization algorithms for deriving low-dimensional approximations of the output space. Under the above framework we derive a novel criterion, Group-JMI-Rand, which captures various high-order target interactions. In an extensive experimental study we showed that our suggested criterion achieves competing performance against various other information theoretic feature selection criteria suggested in the literature.

ASSESSMENT OF AVIATION SECURITY SCREENERS PROFFICIENCY BY MEANS OF APPLYING THE A. BIRNBAUM TWO-PARAMETER MODEL

The necessity to improve assessment of aviation security screeners’ competence has been analyzed. Computer based training systems have been widely used in the process of screeners’ training and evaluating the results of training. The main advantage of similar systems application is the possibility of adaptation to the individual screeners’ requirements by changing the level of training task complexity. The efficiency of applying these systems is proved by foreign researches. To assess the results of screeners’ activity the dangerous image projection data is also used. The analysis of modern approaches to assess the screeners’ activity efficiency showed that they do not completely take into account x-ray image complexity factors affecting the results of screeners’ activity monitoring. There have been presented and tested A. Birnbaum two-parameter model, which is used to assess the screeners’ proficiency competence by means of testing. According to International Civil Aviation Organization recommendations the x-ray image data base has been formed; it includes four blocks of prohibited items. Within the suggested model the probability of detecting prohibited items by aviation security screeners is considered as functions of such parameters as the difference between level of qualification and level of x-ray images complexity, and also between the aviation security screeners’ structure of their professional knowledge. The solution of the task to search A. Birnbaum model parameters values by using maximum likelihood method have been offered. Within the model the qualification level characteristic functions, which describe multi-complexity level of x-ray image interpretation competency of the aviation security screener, were generated and explored. Complex criterion to assess the level of the aviation security screener qualification is offered and tested. The suggested criterion allows to evaluate aviation security screeners’ competency taking into account not only the average level of qualification, but its possible variance. The suggested criterion may be used while selecting and certificating the screeners when the requirement to detect at least 95% prohibited items is applied.

Optimization of regimes of functioning of RTK GPS geodesy networks for cadastre measurements

It is well-known that shift of some points leads to abnormal errors in active geodesy sets which stressed out the importance of research of questions on reliability of measurements results. The aim of the article is forming of basic relations of optimum regimes of RTK cadastre measurements using the suggested criterion of optimality that is requirement to achieve in measurement set the minimum rest informativeness. Solution of this task make it possible to get the transcendental equation allowing to calculate such value of temporal parameters which provides the maximum of residual entropy. Such regime is stated as worse and not recommended for practice. The second research task in the present article is optimization of set of averaged results of measurements. On the basis of results of held measurements it was concluded that the operation of averaging carried out in RTK GPS sets of cadastre measurements while is carried out in low interval of variation of averaging time increasing the accuracy of measurements results doesn’t lead to significant increase of informativeness of such systems and can not be submitted as an effective technical solution for increasing of informativeness.

Chance Hypotheses Testing

This paper considers the problem of testing hypotheses about hybrid distributions which are models representing situations where impreciseness (explained through fuzzy measure) and randomness (explained through probability measure) coexist. A criterion similar to the Neyman-Pearson criterion is proposed for testing a simple chance null hypothesis against a simple chance alternative hypothesis. The suggested criterion has been applied for testing hypotheses about hybrid triangular Bernoulli distribution and hybrid Poisson distribution. Optimal properties of the resulting tests have also been investigated.

Psychiatric detention and treatment: a suggested criterion

<p>Calls for a new Mental Health Act for England and Wales, and the government’s response to those calls, raise the question of why we have mental health legislation. One answer is that we wish to provide criteria for psychiatric detention and compulsory treatment. It is argued that we are willing to coerce some people with mental disorders in this way when we conclude that their ability to make a proper choice is impaired. Mental health legislation could and should be designed to take this into account.</p>