A Framework for Megascale Agent Based Model Simulations on Graphics Processing Units

Agent-based modeling is a technique for modeling dynamic systems from the bottom up. Individual elements of the system are represented computationally as agents. The system-level behaviors emerge from the micro-level interactions of the agents. Contemporary state-of-the-art agent-based modeling toolkits are essentially discrete-event simulators designed to execute serially on the Central Processing Unit (CPU). They simulate Agent-Based Models (ABMs) by executing agent actions one at a time. In addition to imposing an un-natural execution order, these toolkits have limited scalability. In this article, we investigate data-parallel computer architectures such as Graphics Processing Units (GPUs) to simulate large scale ABMs. We have developed a series of efficient, data parallel algorithms for handling environment updates, various agent interactions, agent death and replication, and gathering statistics. We present three fundamental innovations that provide unprecedented scalability. The first is a novel stochastic memory allocator which enables parallel agent replication in O(1) average time. The second is a technique for resolving precedence constraints for agent actions in parallel. The third is a method that uses specialized graphics hardware, to gather and process statistical measures. These techniques have been implemented on a modern day GPU resulting in a substantial performance increase. We believe that our system is the first ever completely GPU based agent simulation framework. Although GPUs are the focus of our current implementations, our techniques can easily be adapted to other data-parallel architectures. We have benchmarked our framework against contemporary toolkits using two popular ABMs, namely, SugarScape and StupidModel.GPGPU, Agent Based Modeling, Data Parallel Algorithms, Stochastic Simulations

Cardiac left ventricular mass and arterial stiffness from childhood to early adulthood - association with cardiometabolic risk factors : the Special Turku Coronary Risk Factor Intervention Project (STRIP)

Background: Cardiac left ventricular mass and arterial stiffness are subclinical markers of cardiovascular disease which are associated with cardiovascular disease and clinical events in adulthood. Aims: The aim of this thesis was to study left ventricular mass and arterial stiffness in childhood and their determinants in terms of cardiometabolic risk factors and ideal cardiovascular health. This thesis also aimed to investigate the effect of a dietary and lifestyle intervention on ideal cardiovascular health and subclinical markers of cardiovascular disease. Subjects and methods: This thesis is a part of the prospective, randomized Special Turku Coronary Risk Factor Intervention Project (STRIP) that has followed initially over 1,000 children for 27 years. Their cardiometabolic risk factors have been repeatedly measured from childhood to adulthood. Children in the intervention group (n=540) have received dietary and lifestyle counseling aimed at improving the quality of dietary fat. Subclinical markers of atherosclerotic cardiovascular disease were examined using noninvasive ultrasonic measurements of carotid and aortic distensibility, pulse wave velocity, carotid intima-media thickness and cardiac left ventricular mass. This study analyses the data of the children who participated in the arterial ultrasound evaluations from the age of 11 to 19 years (n=420–503), and in the cardiac ultrasound assessments from the age of 15 to 19 years (n= 394–420). Results: Cardiac left ventricular mass and arterial stiffness increased with increasing age from childhood to early adulthood. In boys, the arterial stiffness increased more than in girls. It was found that current pulse pressure, weight and physical activity along with birth weight were associated with left ventricular mass in adolescence; overall these factors explained nearly 50% of the variation in left ventricular mass. Childhood blood pressure, body mass index, LDL cholesterol concentration and insulin resistance were associated with arterial stiffness. The dietary and lifestyle intervention was associated with ideal cardiovascular health in adolescence, however, it had no effect on left ventricular mass or arterial stiffness. Conclusions: Marked age-related arterial stiffening is evident already in childhood, particularly in boys. Several cardiometabolic risk factors determine arterial stiffness and cardiac structure already at an early age. Although the dietary and lifestyle intervention promoted ideal cardiovascular health in adolescence, the intervention did not change the subclinical markers of cardiovascular disease at this early age.Sydämen vasemman kammion massa ja valtimoiden jäykistyminen lapsuudesta varhaiseen aikuisuuteen – yhteys kardiometabolisiin riskitekijöihin. Sepelvaltimotaudin Riskitekijöiden Interventioprojekti (STRIP) Tausta: Sydämen vasemman kammion massa ja valtimoiden jäykistyminen ovat valtimoterveyden varhaismarkkereita, jotka ovat yhteydessä sydän- ja verisuonisairauksien päätetapahtumiin aikuisiällä. Tavoite: Väitöskirjatutkimuksen tavoitteena oli tutkia vasemman kammion massaa ja valtimoiden jäykistymistä lapsuudessa, sekä selvittää niitä määrittäviä tekijöitä kardiometabolisten riskitekijöiden ja ihanteellisen sydänterveyden mittareiden avulla. Lisäksi tutkimuksen tavoitteena oli selvittää ravitsemus- ja elämäntapaneuvonnan yhteyttä ihanteelliseen sydänterveyteen ja valtimoterveyden varhaisiin muutoksiin. Menetelmät: Väitöskirjatutkimus on osa prospektiivista, satunnaistettua Sepelvaltimotaudin Riskitekijöiden Interventioprojekti (STRIP) -tutkimusta, jossa on seurattu 27 vuoden ajan alun perin yli 1000 lasta. Tutkittavien lasten sydän- ja verisuonisairauksien riskitekijät on mitattu toistuvasti lapsuudesta aikuisuuteen. Ateroskleroottisen sydän- ja verisuonitaudin varhaisia muutoksia tutkittiin mittaamalla ultraäänellä kaulavaltimon ja aortan distensibiliteetti, pulssiaallon etenemisnopeus, kaulavaltimon intima-median paksuus sekä sydämen vasemman kammion massa. Interventioryhmän lapset (n=540) ovat saaneet ravitsemus- ja elämäntapaneuvontaa, jonka päätavoitteena on ollut ruokavalion rasvan laatuun vaikuttaminen. Tässä työssä käytettiin niiden lasten tietoja, jotka osallistuivat valtimoiden ultraäänitutkimukseen 11– 19 vuoden iässä (n=420–503) ja sydämen ultraäänitutkimukseen 15–19 vuoden iässä (n=394–420). Tulokset: Sydämen vasemman kammion massa kasvoi ja valtimot jäykistyivät lapsuudesta varhaiseen aikuisuuteen. Pojilla valtimoiden jäykistyminen oli voimakkaampaa kuin tytöillä. Tutkimuksessa havaittiin, että pulssipaine, paino ja liikunta sekä syntymäpaino olivat yhteydessä vasemman kammion massaan nuoruudessa selittäen lähes 50 % variaatiosta. Lapsuudessa mitattu verenpaine, painoindeksi sekä seerumin LDL-kolesterolipitoisuus ja insuliiniresistenssi olivat yhteydessä valtimoiden jäykistymiseen lapsuudesta varhaiseen aikuisuuteen. Ravitsemus- ja elämäntapaneuvonta oli yhteydessä ihanteelliseen sydänterveyteen nuoruudessa, mutta sillä ei havaittu olevan yhteyttä valtimoiden jäykistymiseen tai vasemman kammion massaan Johtopäätökset: Valtimot jäykistyvät iän myötä jo lapsuudessa - erityisesti pojilla. Useat kardiometaboliset riskitekijät ovat yhteydessä valtimoiden jäykistymiseen ja sydämen rakenteeseen jo varhaisella iällä. Ravitsemus- ja elämäntapaneuvonnalla voidaan edistää ihanteellista sydänterveyttä nuoruudessa, vaikkakaan se ei ollut yhteydessä valtimotaudin varhaismarkkereihin näin varhaisella iällä

PENGARUH STRUKTUR MODAL, PROFITABILITAS, LIKUIDITAS DAN RASIO AKTIVITAS TERHADAP NILAI PERUSAHAAN PADA PERUSAHAAN SUB SEKTOR MAKANAN DAN MINUMAN YANG TERDAFTAR DI BEI PERIODE TAHUN 2015-2020

Penelitian ini bertujuan untuk mengetahui Pengaruh Struktur Modal, Profitabilitas, Likuiditas dan Rasio Aktivitas Terhadap Nilai Perusahaan Pada Perusahaan Sub Sektor Makanan dan Minuman Yang Terdaftar di BEI Periode Tahun 2015-2020. Pemilihan sampel yang digunakan dalam penelitian ini menggunakan metode purposive sampling yang membatasi pemilihan 11 sampel berdasarkan kriteria tertentu. Data penelitian diperoleh dari Bursa Efek Indonesia. Penelitian ini menggunakan pendekatan kuantitatif. Metode analisis yang dilakukan adalah metode analisis regresi data panel dengan bantuan software Eviews 10. Penelitian ini membuktikan bahwa Debt to Equity Ratio (DER) berpengaruh positif terhadap Nilai Perusahaan (PBV). Return On Equity (ROE) tidak berpengaruh dan terhadap Nilai Perusahaan (PBV). Current Ratio (CR) tidak berpengaruh terhadap Nilai Perusahaan (PBV). Dan Total Assets Turn Over (TATO) berpengaruh positif terhadap terhadap Nilai Perusahaan (PBV)

Communicative Competence In Persons With Aphasia: The Impact Of Executive Function

The purpose of this study was to examine the relationship between executive function and performance on selected linguistic tasks in persons with aphasia secondary to left frontal lesions. A group of 15 persons with aphasia (PWA) completed three communication board tasks of varying levels of complexity and structure. The subject\u27s functional use of the picture/word communication board was tested during a Story Retelling task. In addition, the PWA\u27s executive function skills were examined using six nonverbal tests. The PWA group performance scores were compared to that of the neurologically healthy control group. Results demonstrated that the control group performed significantly better than the PWA group during 2 of the 3 executive function tests. In addition, the control group was more proficient at switching modalities and spontaneously using the target symbols correctly on the picture communication board compared to the PWA group during the story retelling task. There was no significant correlation found when comparing the PWA\u27s language skills and executive function using standardized tools. However, during many of the executive function tests the PWA tended to consistently demonstrate the following error types: perseverative, poor planning and decreased memory of task rules. When given picture pointing board tasks of high and low complexity during a highly structured or relatively unstructured environment, the PWA consistently performed better with the low complexity tasks in a structured environment. While the study showed that aphasia severity can not consistently predict performance on tests of executive function there were some noteworthy behavioral patterns observed during both the executive function and communication board tasks. The PWA demonstrated difficulty with planning, mental flexibility and self monitoring. In addition, response accuracy was usually dependent on the provision of task structure

QUASI-LINEAR EVOLUTION AND ELLIPTIC EQUATIONS

In this article we use a new type of nonlinear elliptic operators  that are associated with left side of elliptic equation and studied their properties. We draw up the form, that is associated with non-linear elliptic operator , studying the properties this operator by means of form. We proved some a priori estimates which are theorems about properties of solutions under certain conditions on the function that forming this equation. We proved the existence of solution of quasi-linear evolution equation with singular coefficients in  space by Galerkin method and showed that a given equationhas a solution in the Sobolev space

Running velocity dynamics in 100 m sprint: comparative analysis of the world top and Estonian top male sprinters

Estonian sprint runners have not achieved great success in international title competitions. This study was conducted to analyze their performance in 100m race. The aim of this study was to perform a comparative analysis of 100m sprint horizontal velocity dynamics in Estonian top level and world top-level male sprinters. We analyzed: 1) athletesʼ relative running velocity during different phases of the distance; 2) the loss of Estonian sprinters to the world best sprinters during different phases of the distance.The study compared Estonian Athletics Championships (2006) menʼs 100m sprint final results with Berlin World Athletics Championships (2009) menʼs 100m final results. In both competitions, interval times were measured for the following sections of the race: 0–30m, 30–60m, 60–80m and 80–100m. We found out that Estonian sprintersʼ acceleration ability is relatively better than the other physical abilities necessary for achieving good results in 100m. Estonian sprinters loose most to the world best sprinters during the last part of the distance, 80–100m. However, the difference in running velocity of Estonian sprinters compared to the world best runners is approximately the same in all three last sections of the distance (30–60m, 60–80 and 80–100m)