scholarly journals Performance Bound for Joint Multiple Parameter Target Estimation in Sparse Stepped-Frequency Radar: A Comparison Analysis

Sensors ◽  
2019 ◽  
Vol 19 (9) ◽  
pp. 2002
Author(s):  
Qiushi Chen ◽  
Xin Zhang ◽  
Qiang Yang ◽  
Lei Ye ◽  
Mengxiao Zhao

A performance bound—Cramér-Rao lower bound (CRLB) for target estimation and detection in sparse stepped frequency radars is presented. The vector formulation of this CRLB is used to obtain a lower bound on the estimation error. The estimation performance can be transformed into different types of CRLB structures. Therefore, the expressions of bounds under three equivalent models are derived separately: time delay and Doppler stretch estimator, joint multiple parameter estimator, and sparse-based estimator. The variables to be estimated include the variances of unknown noise, range, velocity, and the real and imaginary parts of the amplitude. A general performance expression is proposed by considering the echo of the target in the line-of-sight. When the relationship between CRLB and various parameters are discussed in detail, the specific effect of waveform parameters on a single CRLB is compared and analyzed. Numerical simulations demonstrated that the resulting CRLB exhibits considerable theoretical and practical significance for the selection of optimal waveform parameters.

2018 ◽  
Vol 27 (03) ◽  
pp. 1850012 ◽  
Author(s):  
Androniki Tamvakis ◽  
Christos-Nikolaos Anagnostopoulos ◽  
George Tsirtsis ◽  
Antonios D. Niros ◽  
Sofie Spatharis

Voting is a commonly used ensemble method aiming to optimize classification predictions by combining results from individual base classifiers. However, the selection of appropriate classifiers to participate in voting algorithm is currently an open issue. In this study we developed a novel Dissimilarity-Performance (DP) index which incorporates two important criteria for the selection of base classifiers to participate in voting: their differential response in classification (dissimilarity) when combined in triads and their individual performance. To develop this empirical index we firstly used a range of different datasets to evaluate the relationship between voting results and measures of dissimilarity among classifiers of different types (rules, trees, lazy classifiers, functions and Bayes). Secondly, we computed the combined effect on voting performance of classifiers with different individual performance and/or diverse results in the voting performance. Our DP index was able to rank the classifier combinations according to their voting performance and thus to suggest the optimal combination. The proposed index is recommended for individual machine learning users as a preliminary tool to identify which classifiers to combine in order to achieve more accurate classification predictions avoiding computer intensive and time-consuming search.


2011 ◽  
Vol 243-249 ◽  
pp. 4261-4264
Author(s):  
Yin Fei Du ◽  
Xin Yu

A reasonable design strength standard is of great practical significance for reducing pavement diseases. First, the bottom layer tensile stress of the typical pavement structure in the operating period is calculated using computer program BISAR while the overload、the interface link status and construction variability are all considered. And then the bottom layer tensile stresses of the upper and lower base are checked under truck load during construction. According to the relationship between cleavage strength (90d) and unconfined compressive strength (7d), it is deemed that the appropriate design strength standard should be 2.1MPa~3.5MPa. Finally, combined with the results of the unconfined compressive strength of core samples in the field it is proved that the current design standard is a little high.


2020 ◽  
pp. 19-24
Author(s):  
Gunel Valiyeva

Aim: The main aim of the article to analyze the principles and methodology of recreational zoning, the related theories, as well as the factors, which must be successively considered in this process. The methodological basis of the article is the theoretical provisions set forth in the works of Azerbaijani and foreign scholars in defining theoretical and methodological peculiarities of the state programs, international experience in the organization of Recreation Zones. Results: The carried work also demonstrates the feasibility of the conduction of recreational zoning in Azerbaijan, with distinguishing sub-regions within the boundaries of touristic-recreational region of Gusar. The tourism- recreation zone of Gusar specifically predicts the main directions of development of the microdistrict by type of tourism. In accordance to the selection of areas for the Gusar tourism-recreation zone are taken into account the potential for the development of various types of tourism, as well as the suitability for the joint organization of many services. From this point of view, in the formation of recreational tourism zones graphic of dependence is considered the basis for the development of areas. The article shows that the advantages of applying this dependence graphic is suitable for the Gusar recreation and tourism zone. At the same time, the separation of Chilagir-Urva-Khuray, Anig-Laza, Hazra-Sudur micro-recreation regions in the Gusar recreation-tourism zone is due to the existence of similar natural-geographical conditions and conditions for the organization of different types of tourism. The structure of employment is dominated by agriculture and, in part, by tourism. Potato-growing and livestock are the main agricultural sectors. Scientific novelty: The practical significance of the article is the selection of areas suitable for tourism development in the Gusar Tourism and Recreation Zone, and the forecasting of tourism development trends, taking into account the ecological balance.


EMJ Radiology ◽  
2020 ◽  
Author(s):  
Filippo Pesapane

Radiomics is a science that investigates a large number of features from medical images using data-characterisation algorithms, with the aim to analyse disease characteristics that are indistinguishable to the naked eye. Radiogenomics attempts to establish and examine the relationship between tumour genomic characteristics and their radiologic appearance. Although there is certainly a lot to learn from these relationships, one could ask the question: what is the practical significance of radiogenomic discoveries? This increasing interest in such applications inevitably raises numerous legal and ethical questions. In an environment such as the technology field, which changes quickly and unpredictably, regulations need to be timely in order to be relevant.  In this paper, issues that must be solved to make the future applications of this innovative technology safe and useful are analysed.


Author(s):  
А. I. Grabovets ◽  
V. P. Kadushkina ◽  
S. А. Kovalenko

With the growing aridity of the climate on the Don, it became necessary to improve the methodology for conducting the  breeding of spring durum wheat. The main method of obtaining the source material remains intraspecific step hybridization. Crossings were performed between genetically distant forms, differing in origin and required traits and properties. The use of chemical mutagenesis was a productive way to change the heredity of genotypes in terms of drought tolerance. When breeding for productivity, both in dry years of research and in favorable years, the most objective markers were identified — the size of the aerial mass, the mass of grain per plant, spike, and harvest index. The magnitude of the correlation coefficients between the yield per unit area and the elements of its structure is established. It was most closely associated with them in dry years, while in wet years it decreased. Power the correlation of the characteristics of the pair - the grain yield per square meter - the aboveground biomass averaged r = 0.73, and in dry years it was higher (0.91) than in favorable ones (0.61 - 0.70) , between the harvest and the harvest index - r = 0.81 (on average). In dry years, the correlation coefficient increased to 0.92. Research data confirms the greatest importance of the mass of grain from one ear and the plant in the formation of grain yield per unit area in both dry and wet years. In dry years, the correlation coefficient between yield and grain mass per plant was on average r = 0.80; in favorable years, r = 0.69. The relationship between yield and grain mass from the ear was greater — r = 0.84 and r = 0.82, respectively. Consequently, the breeding significance of the aboveground mass and the productivity of the ear, as a criterion for the selection of the crop, especially increases in the dry years. They were basic in the selection.


2018 ◽  
Vol 2 (2) ◽  
pp. 137
Author(s):  
Muhammad Abi Berkah Nadi

Radin Inten II Airport is a national flight in Lampung Province. In this study using the technical analysis stated preference which is the approach by conveying the choice statement in the form of hypotheses to be assessed by the respondent. By using these techniques the researcher can fully control the hypothesized factors. To determine utility function for model forecasting in fulfilling request of traveler is used regression analysis with SPSS program. The analysis results obtained that the passengers of the dominant airport in the selection of modes of cost attributes than on other attributes. From the result of regression analysis, the influence of independent variable to the highest dependent variable is when the five attributes are used together with the R square value of 8.8%. The relationship between cost, time, headway, time acces and service with the selection of modes, the provision that states whether or not there is a decision. The significance of α = 0.05 with chi-square. And the result of Crame's V test average of 0.298 is around the middle, then the relationship is moderate enough.


Author(s):  
Вадим Леонидович Афанасьевский

В статье анализируется проблема взаимоотношений философии права и научной теории права. Рассматриваемая проблема стала особенно актуальной в российском образовательном пространстве в связи с введением после длительного перерыва в государственный образовательный стандарт магистратуры по юриспруденции учебной дисциплины «Философия права». Автор статьи в качестве базисного принимает тезис, согласно которому философия права, являясь сферой философской мысли, и теория права как область научного социогуманитарного знания представляют собой разные типы теоретического дискурса. Исходя из этого, в статье выстраивается теоретическая концепция, согласно которой задачей философии права как философского типа мышления является конструирование или экспликация онтологических, эпистемологических, аксиологических, феноменологических оснований для формирования и функционирования научных теоретико-правовых и историко-правовых построений. Для реализации поставленной в статье задачи подробно рассматриваются ключевые характеристики как теории философского типа, так и идеалов, норм и характеристик научного знания. Выявленное различие экстраполируется на взаимоотношение теории права как продукта научного творчества и философии права как конструкции, задающей базовые мировоззренческие смыслы. В качестве примера выработанных философией права и государства оснований научных теорий прогресса, государства, морали и права, автор приводит взгляды мыслителей западноевропейской философской классики: Т. Гоббса, Ж.-Ж. Руссо, И. Канта, Г.В.Ф. Гегеля. Именно их философские концепции предопределили образы теоретико- и историко-правовых учений XVIII, XIX, XX и даже начала XXI в. Таким образом, отношение философии права и теории права выстраивается по «вертикали»: от онтологического основания к возведению теоретико-правовых и историко-правовых научных построений. The article analyzes the problem of the relationship between the philosophy of law and the scientific theory of law. The problem under consideration has become especially urgent in the Russian educational space in connection with the introduction of the Philosophy of Law discipline master's degree in law after a long break. The author of the article takes as the basis the thesis that the philosophy of law, being the sphere of philosophical thought, and the theory of law as a field of scientific socio-humanitarian knowledge are different types of theoretical discourse. Based on this, the article builds a theoretical concept according to which the task of the philosophy of law as a philosophical type of thinking is the construction or explication of ontological, epistemological, axiological, phenomenological grounds for the formation and functioning of concrete scientific theoretical and legal and historical and legal constructions. To implement the task posed in the article, the key characteristics of both a theory of a philosophical type and ideals, norms and characteristics of scientific knowledge are examined in detail. The revealed difference is extrapolated to the relationship between the theory of law as a product of scientific creativity and the philosophy of law as a construction that sets basic philosophical meanings. As an example of the foundations of the scientific theories of progress, state, morality and law developed by the philosophy of law and the state, the author gives the views and thinkers of the West European philosophical classics T. Hobbes, J.-J. Russo, I. Kant, G.V.F. Hegel. It was their philosophical concepts that predetermined the images of theoretical and historical-legal doctrines of the XVIII, XIX, XX and even the beginning of the XXI centuries. Thus, the attitude of the philosophy of law and the theory of law is built along the «vertical»: from the ontological foundation to the construction of theoretical and historical and historical legal scientific constructions.


2018 ◽  
Vol 15 (5) ◽  
pp. 429-442 ◽  
Author(s):  
Nishant Verma ◽  
S. Natasha Beretvas ◽  
Belen Pascual ◽  
Joseph C. Masdeu ◽  
Mia K. Markey ◽  
...  

Background: Combining optimized cognitive (Alzheimer's Disease Assessment Scale- Cognitive subscale, ADAS-Cog) and atrophy markers of Alzheimer's disease for tracking progression in clinical trials may provide greater sensitivity than currently used methods, which have yielded negative results in multiple recent trials. Furthermore, it is critical to clarify the relationship among the subcomponents yielded by cognitive and imaging testing, to address the symptomatic and anatomical variability of Alzheimer's disease. Method: Using latent variable analysis, we thoroughly investigated the relationship between cognitive impairment, as assessed on the ADAS-Cog, and cerebral atrophy. A biomarker was developed for Alzheimer's clinical trials that combines cognitive and atrophy markers. Results: Atrophy within specific brain regions was found to be closely related with impairment in cognitive domains of memory, language, and praxis. The proposed biomarker showed significantly better sensitivity in tracking progression of cognitive impairment than the ADAS-Cog in simulated trials and a real world problem. The biomarker also improved the selection of MCI patients (78.8±4.9% specificity at 80% sensitivity) that will evolve to Alzheimer's disease for clinical trials. Conclusion: The proposed biomarker provides a boost to the efficacy of clinical trials focused in the mild cognitive impairment (MCI) stage by significantly improving the sensitivity to detect treatment effects and improving the selection of MCI patients that will evolve to Alzheimer’s disease.


Author(s):  
Kiran Ahuja ◽  
Brahmjit Singh ◽  
Rajesh Khanna

Background: With the availability of multiple options in wireless network simultaneously, Always Best Connected (ABC) requires dynamic selection of the best network and access technologies. Objective: In this paper, a novel dynamic access network selection algorithm based on the real time is proposed. The available bandwidth (ABW) of each network is required to be estimated to solve the network selection problem. Method: Proposed algorithm estimates available bandwidth by taking averages, peaks, low points and bootstrap approximation for network selection. It monitors real-time internet connection and resolves the selection issue in internet connection. The proposed algorithm is capable of adapting to prevailing network conditions in heterogeneous environment of 2G, 3G and WLAN networks without user intervention. It is implemented in temporal and spatial domains to check its robustness. Estimation error, overhead, estimation time with the varying size of traffic and reliability are used as the performance metrics. Results: Through numerical results, it is shown that the proposed algorithm’s ABW estimation based on bootstrap approximation gives improved performance in terms of estimation error (less than 20%), overhead (varies from 0.03% to 83%) and reliability (approx. 99%) with respect to existing techniques. Conclusion: Our proposed methodology of network selection criterion estimates the available bandwidth by taking averages, peaks, and low points and bootstrap approximation method (standard deviation) for the selection of network in the wireless heterogeneous environment. It monitors real-time internet connection and resolves internet connections selection issue. All the real-time usage and test results demonstrate the productivity and adequacy of available bandwidth estimation with bootstrap approximation as a practical solution for consistent correspondence among heterogeneous wireless networks by precise network selection for multimedia services.


Author(s):  
A. A. Sheptulin ◽  
O. A. Storonova

Aim of review. Interpretation of published evidence on the relationship between the excessive belching syndrome and functional dyspepsia (FD) and their management in patient care.Key points. According to the Rome IV criteria of functional gastrointestinal disorders (FGID), excessive belching in the absence of other dyspeptic symptoms is to be considered a manifestation of the excessive belching syndrome, which can be of gastric or supragastric nature. Combination of high-resolution manometry and impedancemetry allows an accurate diagnosis of belching and selection of optimal treatment strategy. Belching complicated by other symptoms of dyspepsia is to be considered yet another FD symptom according to the Rome IV criteria of FGID. Prokinetics are recommended to relieve belching in such cases.Conclusion. Understanding the relationship between the excessive belching syndrome and FD requires further research.


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