Unix Tools for Application and System Profiling

Cílem této práce bylo demonstrování využití nástrojů pro profilování aplikací a systémů. Nejprve byly tyto nástroje nalezeny a nastudovány. Také byly rozděleny do kategorií podle jejich účelu. Dále byly tyto nástroje porovnány z hlediska složitosti použití a invazivnosti. Výsledkem bylo rozdělení do tří skupin podle míry složitosti použití nebo invazivnosti. Jako technologie, využité při vytváření modelů, byly zvoleny Apache server a NFS server. Pro vytvoření modelů těchto serverů bylo využito virtualizace systémů pomocí technologie hyper-v. Vytvořeny byly čtyři virtuální stroje. Jeden pro Apache server, další pro NFS server, třetí pro zrcadlení obsahu Apache serveru a poslední pro generování zátěže. Poslední částí této práce je demonstrace využití nalezených nástrojů na vytvořených modelových situacích.The main goal of this thesis was to demonstrate usage of tools for application and system profiling. Initially, these tools was found and studied. They was also divided into categories according to their purpose. After that, these tools was compared according to their complexity of use and invasiveness. As the result of this comparison, these tools was divided into three groups, that express measure of complexity and invasiveness. As technology, used for creating models, was chosen Apache server and NFS server. Virtualization by hyper-v technology was used for putting these models into operation. There was created four virtual machines. Fist one for Apache server, another one for NFS server. Third was for mirroring content of Apache server and the last one for load generation. The last part of this thesis was to demonstrate usage of found tools on the created models.

Risk of complications due to antithrombotic agents in cutaneous surgery: a systematic review and meta‐analysis

Background and objectives: We aimed to determine the risk of complications during cutaneous surgery for the perioperative discontinuation in comparison to the continuation of antithrombotic agents and the bridging of vitamin K antagonists with heparin in comparison to their continuation. Methods: We conducted a systematic review, searching three databases for eligible studies. Methods followed the Cochrane Handbook. We used RoB 2 and ROBINS-I to assess risk of bias. The quality of evidence was judged (GRADE). Fixed-effect meta-analyses were performed. Results: Two randomized-controlled trials and 19 prospective cohort studies were included. It is uncertain whether, compared to its discontinuation, continuing acetylsalicylic acid (risk difference (RD) 0.004, 95 % confidence interval (CI) -0.003 to 0.019) perioperatively increases the risk of significant postoperative bleedings (SPB). Compared to its discontinuation, continuing phenprocoumon perioperatively may increase the risk of SPB (RD 0.02, 95 % CI 0.00 to 0.05). Bridging phenprocoumon with heparin perioperatively may increase the risk of SPB when compared to its continuation (RD 0.07, 95 % CI 0.01 to 0.22). No evidence was found regarding bleeding risks for direct oral anticoagulants. Conclusions: No clear indications of major risks of bleedings when continuing antithrombotic agents during minor skin surgeries were identified. However, the quality of evidence was very low

What determines the fraction of elliptical galaxies in clusters?

We study the correlation between the morphological mix of cluster galaxies and the assembly history of the parent cluster by taking advantage of two independently developed semi-analytic models for galaxy formation and evolution. In our models, both the number of cluster members and that of elliptical members increase as a function of cluster mass, in such a way that the resulting elliptical fractions are approximately independent of cluster mass. The population of cluster ellipticals exhibit a marked bimodal distribution as a function of galaxy stellar mass, with a dip at masses $\sim 10^{10}\,{\rm M}_{\odot}$. In the framework of our models, this bimodality originates from the combination of a strongly decreasing number of galaxies with increasing stellar mass, and a correspondingly increasing probability of experiencing major mergers. We show that the correlation between the measured elliptical fraction and the assembly history of the parent cluster is weak, and that it becomes stronger in models that adopt longer galaxy merger times. We argue that this results from the combined effect of a decreasing bulge production due to a reduced number of mergers, and an increasing survival probability of pre-existing ellipticals, with the latter process being more important than the former.Comment: 8 pages, 3 figures, accepted for publication in MNRA

Prediction of the thermal release of transactinide elements (112 ≤ Z ≤ 116) from metals

Metallic catcher foils have been investigated on their thermal release capabilities for future superheavy element studies. These catcher materials shall serve as connection between production and chemical investigation of superheavy elements (SHE) at vacuum conditions. The diffusion constants and activation energies of diffusion have been extrapolated for various catcher materials using an atomic volume based model. Release rates can now be estimated for predefined experimental conditions using the determined diffusion values. The potential release behavior of the volatile SHE Cn (E112), E113, Fl (E114), E115, and Lv (E116) from polycrystalline, metallic foils of Ni, Y, Zr, Nb, Mo, Hf, Ta, and W is predicted. Example calculations showed that Zr is the best suited material in terms of on-line release efficiency and long-term operation stability. If higher temperatures up to 2773K are applicable, tungsten is suggested to be the material of choice for such experiment

A Realistic Cyclist Model for SUMO Based on the SimRa Dataset

Increasing the modal share of bicycle traffic to reduce carbon emissions, reduce urban car traffic, and to improve the health of citizens, requires a shift away from car-centric city planning. For this, traffic planners often rely on simulation tools such as SUMO which allow them to study the effects of construction changes before implementing them. Similarly, studies of vulnerable road users, here cyclists, also use such models to assess the performance of communication-based road traffic safety systems. The cyclist model in SUMO, however, is very imprecise as SUMO cyclists behave either like slow cars or fast pedestrians, thus, casting doubt on simulation results for bicycle traffic. In this paper, we analyze acceleration, velocity, and intersection left-turn behavior of cyclists in a large dataset of real world cycle tracks. We use the results to derive an improved cyclist model and implement it in SUMO.Comment: Accepted for the 20th Mediterranean Communication and Computer Networking Conference (MedComNet 2022

Meals described as healthy or unhealthy match public health education in England

Dietary guidelines for the general public aim to lower the incidence of nutrition-related diseases by influencing habitual food choices. Yet little is known about how well the guidelines are matched by the actual practices that people regard as healthy or unhealthy. In the present study, British residents were asked in a cognitive interview to write a description of an occasion when either they ate in an unhealthy way or the eating was healthy. The reported foods and drinks, as well as sort of occasion, location, people present and time of day, were categorised by verbal and semantic similarities. The number of mentions of terms in each category was then contrasted between groups in exact probability tests. Perceived unhealthy and healthy eating occasions differed reliably in the sorts of foods and the contexts reported. There was also full agreement with the national guidelines on eating plenty of fruit and vegetables, eating small amounts of foods and drinks high in fat and/or sugar, drinking plenty of water, and cutting down on alcohol. There was a tendency to regard choices of bread, rice, potatoes, pasta and other starchy foods as healthy. Reported healthy and unhealthy eating did not differ in incidences of meat, fish, eggs, beans and other non-dairy sources of protein or of dairy foods and milk. These results indicate that operationally clear recommendations by health professionals are well understood in this culture but members of the public do not make clear distinctions in the case of foods that can be included in moderate amounts in a healthy diet

Improving the Accuracy of IVC Simulation using Crowd-sourced Geodata

Abstract-We discuss the use of crowd-sourced geodata in simulative evaluations of Inter-Vehicle Communication (IVC) protocol designs. Typically, network simulation tools, which have been improved over decades of network research, are used for evaluating communication systems. In the area of IVC, however, additional challenges have to be met. Most important, the mobility of vehicles in network simulation needs to be represented accurately, e.g., using road traffic microsimulation techniques. These can be integrated with network simulation tools in order to provide a holistic view on the overall system performance. Obviously, the quality of these approaches inherently depends on the quality of provided map data. The OpenStreetMap project provides a community-maintained repository under an open license model. The available crowd-sourced geodata not only consists of road topology data but also includes fine-grained details such as traffic lights, speed limits, and even information about buildings, which represent obstacles for wireless communication. Using our Veins simulation framework, we show that this data increases the accuracy of IVC simulation

Star formation activity of intermediate redshift cluster galaxies out to the infall regions

We present a spectroscopic analysis of two galaxy clusters out to ~4Mpc at z~0.2. The two clusters VMF73 and VMF74 identified by Vikhlinin et al. (1998) were observed with MOSCA at the Calar Alto 3.5m telescope. Both clusters lie in the ROSAT PSPC field R285 and were selected from the X-ray Dark Cluster Survey (Gilbank et al. 2004) that provides optical V- and I-band data. VMF73 and VMF74 are located at respective redshifts of z=0.25 and z=0.18 with velocity dispersions of 671 km/s and 442 km/s, respectively. The spectroscopic observations reach out to ~2.5 virial radii. Line strength measurements of the emission lines H_alpha and [OII]3727 are used to assess the star formation activity of cluster galaxies which show radial and density dependences. The mean and median of both line strength distributions as well as the fraction of star forming galaxies increase with increasing clustercentric distance and decreasing local galaxy density. Except for two galaxies with strong H_alpha and [OII] emission, all of the cluster galaxies are normal star forming or passive galaxies. Our results are consistent with other studies that show the truncation in star formation occurs far from the cluster centre.Comment: 15 pages, 12 figures. A&A in pres