Implementation of novel methods of global and nonsmooth optimization : GANSO programming library

We discuss the implementation of a number of modern methods of global and nonsmooth continuous optimization, based on the ideas of Rubinov, in a programming library GANSO. GANSO implements the derivative-free bundle method, the extended cutting angle method, dynamical system-based optimization and their various combinations and heuristics. We outline the main ideas behind each method, and report on the interfacing with Matlab and Maple packages. <br /

Predicting and controlling the dynamics of infectious diseases

This paper introduces a new optimal control model to describe and control the dynamics of infectious diseases. In the present model, the average time of isolation (i.e. hospitalization) of infectious population is the main time-dependent parameter that defines the spread of infection. All the preventive measures aim to decrease the average time of isolation under given constraints

Dynamics of Ebola epidemics in West Africa 2014

This paper investigates the dynamics of Ebola virus transmission in West Africa during 2014. The reproduction numbers for the total period of epidemic and for different consequent time intervals are estimated based on a newly suggested linear model. It contains one major variable - the average time of infectiousness (time from onset to hospitalization) that is considered as a parameter for controlling the future dynamics of epidemics. Numerical implementations are carried out on data collected from three countries Guinea, Sierra Leone and Liberia as well as the total data collected worldwide. Predictions are provided by considering different scenarios involving the average times of infectiousness for the next few months and the end of the current epidemic is estimated according to each scenario

The Origin of Doping in Quasi-Free Standing Graphene on Silicon Carbide

We explain the robust p-type doping observed for quasi-free standing graphene on hexagonal silicon carbide by the spontaneous polarization of the substrate. This mechanism is based on a bulk property of SiC, unavoidable for any hexagonal polytype of the material and independent of any details of the interface formation. We show that sign and magnitude of the polarization are in perfect agreement with the doping level observed in the graphene layer. With this mechanism, models based on hypothetical acceptor-type defects as they are discussed so far are obsolete. The n-type doping of epitaxial graphene is explained conventionally by donor-like states associated with the buffer layer and its interface to the substrate which overcompensate the polarization doping.Comment: 10 pages, 1 figur

Accepting a scholarly identity: Gifted students, academic crowd membership, and identification with school

This study examined identification with school among middle school students and its relationship with academic crowd membership, a public expression of one’s academic orientation. Of the 127 Grade 6 to 8 students in the sample, 55 reported participation in a gifted program; 44% of these gifted students did not claim affiliation with the academic crowd. There was a positive correlation between identification with school and the importance placed on membership for students in the academic crowd, both gifted and nongifted. The California Bully Victimization Scale was used to determine that no group was more likely to have been victimized. Cluster analysis of crowd memberships indicated that gifted students not in the academic crowd had few other crowd memberships, suggesting that middle school may be an important time to encourage a willingness to be viewed by peers as academically oriented through promoting identification with school

Computed tomography data colouring based on photogrammetric images

Nowadays various methods and sensors are available for 3D reconstruction tasks; however, it is still necessary to integrate advantages of different technologies for optimizing the quality 3D models. Computed tomography (CT) is an imaging technique which takes a large number of radiographic measurements from different angles, in order to generate slices of the object, however, without colour information. The aim of this study is to put forward a framework to extract colour information from photogrammetric images for corresponding Computed Tomography (CT) surface data with high precision. The 3D models of the same object from CT and photogrammetry methods are generated respectively, and a transformation matrix is determined to align the extracted CT surface to the photogrammetric point cloud through a coarse-to-fine registration process. The estimated pose information of images to the photogrammetric point clouds, which can be obtained from the standard image alignment procedure, also applies to the aligned CT surface data. For each camera pose, a depth image of CT data is calculated by projecting all the CT points to the image plane. The depth image is in principle should agree with the corresponding photogrammetric image. The points, which cannot be seen from the pose, but are also projected on the depth image, are excluded from the colouring process. This is realized by comparing the range values of neighbouring pixels and finding the corresponding 3D points with larger range values. The same procedure is implemented for all the image poses to obtain the coloured CT surface. Thus, by using photogrammetric images, we achieve a coloured CT dataset with high precision, which combines the advantages from both methods. Rather than simply stitching different data, we deep-dive into the photogrammetric 3D reconstruction process and optimize the CT data with colour information. This process can also provide an initial route and more options for other data fusion processes

Psychological heterogeneity among honors college students

Greater knowledge of the psychology of honors college students will help to inform program administrators, counselors, residence life assistants, and faculty about how they may provide support to those with the greatest need. Via an online survey, personality, perfectionism, and suicidal ideation data were collected from honors college students (N = 410, 73% female). Using latent profile analysis, students were classified by their responses to the Big Five Inventory personality measure into five profiles. Risk factors of high perfectionism and suicidal ideation scores were found in two of the profiles, suggesting students with these personality characteristics may need enhanced psychological support. The largest profile (35% of students) had extraversion scores above the norm, but all other profiles had introverted scores below the norm. Neuroticism scores were also higher than the norm in the introverted profiles, which represented a majority of the honors college students

Coverage in WLAN: Optimization Model and Algorithm

When designing wireless communication systems, it is very important to know the optimum numbers of access points (APs) in order to provide a reliable design. In this paper we describe a mathematical model developed for finding the optimal number and location of APs. A new Global Optimization Algorithm (AGOP) is used to solve the problem. Results obtained demonstrate that the model and software are able to solve optimal coverage problems for design areas with different types of obstacles and number of users

Модель и метод определения оптимальной структуры системы обеспечения безопасности для критической информационной инфраструктуры

The article investigates the problem of information security of critical information infrastructures. The features of critical objects from the point of view of collecting, processing, storing and transmitting information are analysed. The set of functions performed by the information security system in critical infrastructures and the dependencies between these functions are studied. A model of the security system is proposed and the require ments for this model are defined. At the same time, the set of relations between objects and threats is represented in the form of an object-threat relationship graph, in which an edge connecting the j-th object with the i-th threat exists only when the i-th threat can directly affect the j-th object. To protect objects of critical information infrastructures from possible threats, a set of necessary methods and tools has been introduced into the model of the security system, which converts a two-sided graph into a three-sided one, such as “object – method – threat”. Further in the article, the problem of determining the optimal structure of the security system for critical information infrastructure objects is considered. It is assumed here that each threat can affect several objects, and that any object can be affected by more than one threat. The solution of this problem makes it possible to minimize the material costs to implement the methods and tools for protection and minimize damage from a security breach. Исследована проблема информационной безопасности критических информационных инфраструктур. Проанализированы особенности критически важных объектов с точки зрения сбора, обработки, хранения и передачи информации. Изучены совокупность функций, выполняемых системой обеспечения безопасности информации в критических инфраструктурах, и зависимости между этими функциями. Предложена модель системы обеспечения безопасности и определены требования, предъявляемые к ней. Множество отношений между объектами и угрозами представлено в виде графа отношений «объект – угроза», в котором ребро, связывающее j-й объект с i-й угрозой, существует только тогда, когда i-я угроза может воздействовать напрямую на j-й объект. Для защиты объектов критических информационных инфраструктур от возможных угроз в модель системы обеспечения безопасности введено множество необходимых методов и средств, преобразующее двухдольный граф в трехдольный, типа «объект – метод – угроза». Рассмотрена задача определения оптимальной структуры системы обеспечения безопасности объектов критической информационной инфраструктуры, решение которой позволит свести к минимуму материальные затраты на реализацию средств защиты и ущерб от нарушения безопасности.

Detecting K-complexes for sleep stage identification using nonsmooth optimisation

The process of sleep stage identification is a labour-intensive task that involves the specialized interpretation of the polysomnographic signals captured from a patient&rsquo;s overnight sleep session. Automating this task has proven to be challenging for data mining algorithms because of noise, complexity and the extreme size of data. In this paper we apply nonsmooth optimization to extract key features that lead to better accuracy. We develop a specific procedure for identifying K-complexes, a special type of brain wave crucial for distinguishing sleep stages. The procedure contains two steps. We first extract &ldquo;easily classified&rdquo; K-complexes, and then apply nonsmooth optimization methods to extract features from the remaining data and refine the results from the first step. Numerical experiments show that this procedure is efficient for detecting K-complexes. It is also found that most classification methods perform significantly better on the extracted features