A Coherent Accumulation Detection Method Based on SA-DPT for Highly Maneuvering Target

The emergence of highly maneuverable weak targets has led to a serious degradation or even failure of traditional radar detection. In this paper, a coherent accumulation algorithm based on combination of scaling algorithm(SA) and discrete polynomial-phase Transform(DPT) is proposed in terms of the calculation burden and detection performance, which can, firstly, perform fewer times of speed parameter compensation based on SA for the transmitted signal; secondly, use segmented FFT to estimate the time delay range of the target initial distance for the echo signal, and then use the DPT algorithm to complete the parameter estimation such as target speed and acceleration within the estimated time delay unit, while analyzing the effects of the number of segments, compensation speed and delay unit on the detection performance, and giving out the output SNR and the amount of complex multiplication of the proposed algorithm. Finally, the proposed algorithm has been verified by experimental data for its effectiveness in accumulation gain and parameter estimation. This method is for sub-optimal estimation, requiring much less computation than full-parameter search methods, but performs better than non-parametric search methods in detecting weak signals.

Expert System for Aerial Vehicle Deployment System Selection

An expert system is a programmable device developed to provide automation for engineering problem solving. It is composed of artificial intelligence modules, subroutine functions, and databases. Under this framework, a design process is proposed to assist the conceptual design of aerial vehicles' deployment systems. The problem is first defined by a set of design requirements for take-off, landing, and cruise. The values are then translated to a set of performance parameters needed for the design process via a newly developed parametric search algorithm. Such parameters are categorised by a fuzzy inference module to determine the most suitable deployment-propulsion system, for conventional and V/STOL vehicles. Through the use of linear and neural network regression, a number of aerodynamic terms are estimated to support flight mechanics analyses, where the optimal take-off and landing thrust vectors are determined. Engine specifications are deduced in terms of unit thrust, weight, bypass ratio and dimension. The design process demonstrates effectiveness in sizing engines for V/STOL operations.

Expert System for Aerial Vehicle Deployment System Selection

An expert system is a programmable device developed to provide automation for engineering problem solving. It is composed of artificial intelligence modules, subroutine functions, and databases. Under this framework, a design process is proposed to assist the conceptual design of aerial vehicles' deployment systems. The problem is first defined by a set of design requirements for take-off, landing, and cruise. The values are then translated to a set of performance parameters needed for the design process via a newly developed parametric search algorithm. Such parameters are categorised by a fuzzy inference module to determine the most suitable deployment-propulsion system, for conventional and V/STOL vehicles. Through the use of linear and neural network regression, a number of aerodynamic terms are estimated to support flight mechanics analyses, where the optimal take-off and landing thrust vectors are determined. Engine specifications are deduced in terms of unit thrust, weight, bypass ratio and dimension. The design process demonstrates effectiveness in sizing engines for V/STOL operations.

Investigation of the stress parameter values for the stochastic simulation of shallow (h<45km) interface earthquakes of the southern Aegean Sea subduction zone

&lt;p&gt;In the present work, we examine the stress parameter values for the stochastic simulation modeling of shallow interface (h&lt;45km) earthquakes in the southern Aegean Sea subduction zone. Using the extended-source model (EXSIM code), the stochastic stress parameter is estimated for several of these earthquakes, which are typically associated with thrust faulting. The assessment is performed using a Monte Carlo parametric search (non-linear optimization) of the stress parameter values, realized through an adapted neighborhood algorithm (Wathelet, 2008). In this approach, we estimate the stress parameter which minimizes the total root mean square (rms) misfit between observed and simulated Fourier Amplitude Spectra (FAS) for all records of each event available in the strong motion database. We also employ appropriate source and path parameters (e.g., moment magnitude, fault dimensions, high-frequency spectral attenuation, etc.), from previous works on strong-motion simulations, considering earthquakes in the range &lt;strong&gt;M&lt;/strong&gt;4.4 to &lt;strong&gt;M&lt;/strong&gt;6.6. For several recording stations, we employed site-specific transfer functions, derived from a generalized inversion of strong motion records, considering the seismic source and propagation path of the seismic events in terms of their frequency content (Drouet et al., 2008; Grendas et al., 2018). For the remaining stations, the assessment of site-effects on seismic motions was performed based on the Vs30 values available for all recording stations. Using these values, soil classes according to NEHRP (1994) have been assigned and we employed generic transfer functions for NEHRP site conditions A/B, C and D (together with the corresponding &amp;#954;0 values), as these were available from previous work for Greece by several authors (Margaris and Boore, 1998, Margaris and Hatzidimitriou, 2002; Klimis et al., 1999, 2006). The final comparisons show that the FAS of the strong motion data can be adequately matched (in most cases) by the synthetic data from the EXSIM simulations, using stress parameter values less than 100bars. This value is quite different from results obtained for larger depth interface and inslab events of the Aegean Sea and Vrancea subduction zones (e.g., Sokolov et al., 2005; Kkallas et al., 2018), which show much larger stress parameters (&gt;200bar) for &lt;strong&gt;M&lt;/strong&gt;&gt;6 events. These findings suggest that the event hypocentral depth is a critical factor regarding the observed stress parameter affecting accordingly the seismic hazard estimation. Strong Intermediate-depth events (h&gt;45km) require large stress parameters, while shallow interface thrust events show rather similar stress parameter values with the typical shallow back-arc normal and strike-slip events of the Aegean region. &lt;strong&gt;This research is co-financed by Greece and the European Union (European Social Fund- ESF) through &lt;/strong&gt;&lt;strong&gt;the Operational Programme &amp;#171;Human Resources Development, Education and Lifelong Learning&amp;#187; in &lt;/strong&gt;&lt;strong&gt;the context of the project &amp;#8220;Reinforcement of Postdoctoral Researchers - 2&lt;/strong&gt;&lt;strong&gt;nd &lt;/strong&gt;&lt;strong&gt;Cycle&amp;#8221; (MIS-5033021), &lt;/strong&gt;&lt;strong&gt;implemented by the State Scholarships Foundation (&amp;#921;&amp;#922;&amp;#933;).&lt;/strong&gt;&lt;/p&gt;

Robust parameter search for IC tray injection molding using regrind resin

Quality consistency is essential in maximizing the productivity rate of the injection molding process and minimizing the production cost. The quality consistency problem is particularly acute in the case of injection molding processes performed using regrind resin, for which the rheological properties are less uniform and more unpredictable than those of virgin material. Accordingly, the present study proposes a two-stage approach for optimizing the injection molding process parameters in such a way as to achieve a consistent molding quality over repeated injection molding cycles. In the first stage, the values of the injection speed/pressure, velocity-to-pressure (V/P) switchover point, and packing pressure are individually determined based on an inspection of the cavity pressure profile and machine parameters provided by the injection molding machine controller. In the second stage, a robust parametric search method based on a first-order regression model is employed to determine the optimal combination of the process parameter settings. Using an Integrated Circuit (IC) tray fabricated from regrind resin for illustration purposes, the results confirm that the proposed method overcomes the problem of small variations in the melt quality and therefore provides an effective technique for improving the yield rate and quality of the continuous mass production.

Low energetic Interstellar hydrogen atoms in the heliosphere: Decade of IBEX observations

&lt;p&gt;This work is devoted to the analysis of the interstellar hydrogen fluxes measured by IBEX spacecraft from 2009 to 2018. To calculate the fluxes we use our 3D time-dependent kinetic model of the hydrogen distribution in the heliosphere that takes into account non-maxwellian behavior of the velocity distribution function of hydrogen atoms due to charge exchange with protons at the heliospheric boundary. The temporal variations of the hydrogen fluxes during the entire solar cycle are considered and analyzed by comparison of the IBEX-Lo data and the model results. During solar maximum the measured fluxes are too low, therefore we choose several years 2009-2011 and 2017-2018 when the signal-to-noise ratio is appropriate. A parametric search is performed to determine the influence of different model parameters on the full sky maps of the fluxes. It is found that solar radiation pressure is the most crucial parameter for the position of the maximum fluxes, while the heliolatitudinal variations of the charge exchange ionization rate influence the shape of the maps during solar minimum conditions. The quantitative differences between the data and the model results are demonstrated, and several possible reasons for them are discussed.&lt;/p&gt;

Computing the Yolk in Spatial Voting Games without Computing Median Lines

The yolk is an important concept in spatial voting games: the yolk center generalises the equilibrium and the yolk radius bounds the uncovered set. We present near-linear time algorithms for computing the yolk in the plane. To the best of our knowledge our algorithm is the first that does not precompute median lines, and hence is able to break the best known upper bound of O(n4/3) on the number of limiting median lines. We avoid this requirement by carefully applying Megiddo’s parametric search technique, which is a powerful framework that could lead to faster algorithms for other spatial voting problems.

C/VDdb: a multi-omics expression profiling database for a knowledge-driven approach in cardiovascular disease (CVD)

The cardiovascular disease (C/VD) database is an integrated and clustered information resource that covers multi-omic studies (microRNA, genomics, proteomics and metabolomics) of cardiovascular-related traits with special emphasis on coronary artery disease (CAD). This resource was built by mining existing literature and public databases and thereafter manual biocuration was performed. To enable integration of omic data from distinct platforms and species, a specific ontology was applied to tie together and harmonise multi-level omic studies based on gene and protein clusters (CluSO) and mapping of orthologous genes (OMAP) across species.CAD continues to be a leading cause of death in the population worldwide, and it is generally thought to be an age-related disease. However, CAD incidence rates are now known to be highly influenced by environmental factors and interactions, in addition to genetic determinants. With the complexity of CAD aetiology, there is a difficulty in research studies to elucidate general elements compared to other cardiovascular diseases.Data from 92 studies, covering 13945 molecular entries (4353 unique molecules) is described, including data descriptors for experimental setup, study design, discovery-validation sample size and associated fold-changes of the differentially expressed molecular features (p-value<0.05). A dedicated interactive web interface, equipped with a multi-parametric search engine, data export and indexing menus are provided for a user-accessible browsing experience.The main aim of this work was the development of a data repository linking clinical information and molecular differential expression in several CVD-related traits from multi-omics studies (genomics, transcriptomics, proteomics and metabolomics). As an example case of how to query and identify data sets within the database framework and concomitantly demonstrate the database utility, we queried CAD-associated studies and performed a systems-level integrative analysis.URL: www.padb.org/cvd

The (1|1)-Centroid Problem in the Plane with Distance Constraints

In 1982, Drezner proposed the [Formula: see text]-centroid problem on the plane, in which two players, called the leader and the follower, open facilities to provide service to customers in a competitive manner. The leader opens the first facility, and the follower opens the second. Customers will each patronize the facility closer to them (with ties broken in favor of the first one), thereby deciding the market share of the two facilities. The goal is to find the best position for the leader’s facility so that its market share is maximized. The best algorithm of this problem is an [Formula: see text]-time parametric search approach, which searches over the space of market share values. In the same paper, Drezner also proposed a generalized version of [Formula: see text]-centroid problem by introducing a minimal distance constraint [Formula: see text], such that the follower’s facility is not allowed to be located within a distance [Formula: see text] from the leader’s. He proposed an [Formula: see text]-time algorithm for this generalized version by identifying [Formula: see text] points as the candidates of the optimal solution and checking the market share for each of them. In this paper, we develop a new parametric search approach searching over the [Formula: see text] candidate points, and present an [Formula: see text]-time algorithm for this generalized version, thereby closing the [Formula: see text] gap between the two bounds.