Applied type system

We present a type system that can effectively facilitate the use of types in capturing invariants in stateful programs that may involve (sophisticated) pointer manipulation. With its root in a recently developed framework Applied Type System (ATS), the type system imposes a level of abstraction on program states by introducing a novel notion of recursive stateful views and then relies on a form of linear logic to reason about such views. We consider the design and then the formalization of the type system to constitute the primary contribution of the paper. In addition, we mention a prototype implementation of the type system and then give a variety of examples that attests to the practicality of programming with recursive stateful views.National Science Foundation (CCR-0224244, CCR-0229480

Comparison of Multivariate and Univariate Models for Genetic Evaluation of Milk Yield based on Test Day Data

2000 Mathematics Subject Classification: 62H12, 62P99Multivariate and univariate lactation models were applied to test day data to predict genetic value of daily milk yield of a sample of Black and White cows. The models for genetic evaluation include a set of fixed main effects, fixed regression on functions of days im milk, random effects of permanent environment within lactation, random additive genetic effect and residual effect. Under multivariate model for daily milk yield test day records within lactation are considered as repeated measurements, and different lactations are treated as separate traits. Univariate model is applied for each lactation using test day yield as repeated measure. The variance components, genetic parameters and ranging of the animals through the multivariate and univariate metod were compared

α-Mellin Transform and One of Its Applications

MSC 2010: 35R11, 44A10, 44A20, 26A33, 33C45We consider a generalization of the classical Mellin transformation, called α-Mellin transformation, with an arbitrary (fractional) parameter α > 0. Here we continue the presentation from the paper [5], where we have introduced the definition of the α-Mellin transform and some of its basic properties. Some examples of special cases are provided. Its operational properties as Theorem 1, Theorem 2 (Convolution theorem) and Theorem 3 (α-Mellin transform of fractional R-L derivatives) are presented, and the proofs can be found in [5]. Now we prove some further properties of this integral transform, useful for its application to solving some fractional order differential equations

Аrtificial intelligence system problems and opportunities to solve them with design patterns

Artificial intelligence (AI) is entering almost every sphere of modern life. Its influence cannot be ignored and it permeates almost all modern systems. The requirements for the development of such systems are many, he must not only know the capabilities of AI, but also be able to create a complete system that meets certain quality requirements. Some design patterns are provided to help AI developers. Common development practices at the architecture and project  level can be encapsulated as patterns to reuse and bring the expertise in this relatively new technology to all developers. For some of the problems discussed, design patterns can offer an effective solution and thus support the overall development process. The research goal is to explore common problems in AI systems and patterns that can offer a solution

Performance evaluation of machine learning models for credit risk prediction

The purpose of this research paper is to propose an approach for calculating the optimal threshold for predictions generated by binomial classification models for credit risk prediction. Our approach is considering the cost matrix and cumulative profit chart for setting the threshold value. In the paper we examine the performance of several models trained with homogeneous (Random Forest, XGBoost, etc.) and heterogeneous (Stacked Ensemble) ensemble classifiers. Models are trained on data extracted from Lending Club website. Different evaluation measures are derived to compare and rank the fitted models. Further analysis reveals that application of trained models with the set according to the proposed approach threshold leads to significantly reduced default loans ratio and at the same time improves the credit portfolio structure of the Peer-to-Peer lending platform. We evaluate the models performance and demonstrate that with machine learning models Peer-to-Peer lending platform can decrease the default loan ratio by 8% and generate profit lift of 16%

Integral Transforms Method to Solve a Time-Space Fractional Diffusion Equation

Mathematical Subject Classification 2010: 35R11, 42A38, 26A33, 33E12.The method of integral transforms based on using a fractional generalization of the Fourier transform and the classical Laplace transform is applied for solving Cauchy-type problem for the time-space fractional diffusion equation expressed in terms of the Caputo time-fractional derivative and a generalized Riemann-Liouville space-fractional derivative

Study of the Opinion of Medical Specialists and Social Workers Regarding Medico-Social Assistance Organization for Older Adults and Elderly People in Home Settings

According to the National Statistical Institute, an older adult person has an average of 4-6 illnesses. In most of the cases chronic illnesses lead to vital function disturbance, partial or overall loss of self-service, moving, socialization, and working ability. All these factors impose system organization of constant medical and social cares.The last counting census dated 01 February 2011 determines a vast increase of individuals with 50% and more disability. These individuals have needs of complex medico-social assistance, mostly these of the most vulnerable group – solitary older adults, elderly people and disabled individuals.Research Objective: The aim of this article is analysis of the opinion of medical specialists and social workers regarding medico-social assistance organization for older adults and solitary elderly people in home settings as a basis for optimization of offered services and needed resource.Subjects and Methods: The research object is the opinion of medical specialists and social workers on the needs, current situation and organization of medico-social help for older adults and solitary elderly individuals in home settings.The applied methods include: sociological inquiry (anonymous); statistical processing and graphical interpretation of the analyzed results.Results and Discussion: The research results prove the inefficiency of the current system, necessity of change of forms and organization leading to better medical and social services in home settings.Conclusion: Specialist opinion regarding organisation of medical-social assistance for adults and old people confirms the necessity of offering, experimenting and using new mixed forms of the assistance offered in home settings

Stress reasons among university students at the Veliko Tarnovo affiliate of the Medical University of Varna

Въведение: Основната функция на учебната дейност в университета се състои в качествена подготовка на висококвалифицирани специалисти. Обучението на студентите се измерва с успеха, който са постигнали, но от голямо значение е и това как това обучение се отразява върху физическото и психическото им здраве. Умственият труд е основна дейност в обучението. Съпроводен с продължително нервно-психическо напрежение, може да предизвика напрежение и стрес.Цел на проучването: Да се идентифицират причините, проявленията и прийомите за преодоляване на стреса при студентите първокурсници от специалностите „Акушерка ` и „Медицинска сестра` във Филиал Велико Търново с цел запазване на тяхното физическо и психическо здраве.Материал и методи: Проучено е мнението на 19 студенти от специалността „Акушерка` и 20 студенти от специалността „Медицинска сестра` от Филиал Велико Търново. Използвани са документален, социологически метод и графичен анализ.Резултати: Стресът при студентите е променлива величина. През първия семестър преобладава „тревожност и безпокойство през цялото време` - 47%, през втория семестър водещ при акушерките е „стрес с непостоянен характер` - 36%, a при медицинските сестри - „силната тревожност`, 38%. Най-високо е нивото на стрес преди изпит. През първия семестър водещите причини са свързани с изпитите, a през втория семестър - с учебния процес. По време на семестъра преобладават емоционалните проявления на стреса, a по време на изпити - физиологичните. Прийомите, които използват за преодоляване на стреса, се променят към по-природосъобразни.Introduction: The quality preparation of highly qualified and competitive specialists is the basic academic function of the university. Students` education is measured by the achieved academic grade. How this education reflects on the overall development of the students and how it builds up students as personalities and their physical and mental health is of high importance. Intellectual work is the basic action in education. Assisted by extended neuropsychological tension, it could provoke mental burnout, tension and stress which could be expressed in different negative activities.Aim: The aim of this study is to identify the mainstress reasons, behavior and ways to overcome them among first-year university students in the Midwife and Nurse programs at the Veliko Tarnovo Affiliate as well as the physical and mental health prevention and the forming of a positive attitude toward the academic process.Materials and Methods: The study included 19 students from the Midwife program and 20 students from the Nurse program, all aged between 19 and 53 studying at the Veliko Tarnovo Affiliate. Their opinion was studied.Documentary and sociological (inquiry) methods and graphic analysis were used for the purpose of current research.Results: Stress among first-year students has changed throughout the time. `Anxiety and inconvenience all the time` is typical for the first semester at the university - 47% while `stress of changeable character` was predominant among Midwife students during the second semester - 36% and `high anxiety` was prevalent among Nurse students - 38%, again during the same semester. The highest stress level is measured prior to exams. The stress reasons also change. The basic reasons during the first semester are linked to exams while those of the second semester are related to the training process. Basic emotional stress activities during both terms are: fear and anxiety, and confidence loss while the behavior activities are: time deficiency, sleep disturbance, low work efficiency. Physical stress on different human organs and systems is dominant during the exam period. Students use ways to overcome stress, which become more natural with time