ROZBIERALNA KOMORA PRÓŻNIOWA JAKO INNOWACYJNE STANOWISKO BADAWCZE PRZEZNACZONE DO BADAŃ NAD POPRAWĄ PARAMETRÓW EKSPLOATACYJNYCH ELEKTROENERGETYCZNEJ APARATURY ŁĄCZENIOWEJ

Polish power industry is characterized by outdated elements and in poor technical condition. This applies mainly to overhead lines operating at medium and high voltage (MV and HV) levels. Moreover, the Energy Regulatory Office (ERO) requires the Distribution System Operators to supply electricity with specified parameters, ensuring uninterrupted electricity supply to end users. Failure to meet these conditions results in specific financial penalties. In connection with with the above, there is a strong need to upgrade the existing electricity grids using modern equipment. The article presents an innovative, original research position based on the so-called dismountable vacuum chamber, which allows to conduct research on improving the performance of modern switching equipment used in Smart Grid networks. The article also presents the results of the electric strength tests of the inter-contact break in order to confirm the correctness of operation of the described test stand.Polska elektroenergetyka cechuje się elementami przestarzałymi oraz w złej kondycji technicznej. Dotyczy to przede wszystkim linii napowietrznych pracujących na poziomie średnich i wysokich napięć (SN i WN). Co więcej, Urząd Regulacji Energetyki (URE) wymaga od Operatorów Systemu Dystrybucyjnego dostarczania energii elektrycznej o określonych parametrach, zapewniających odbiorcom końcowym bezprzerwowe dostawy energii elektrycznej. Niespełnienie tych warunków skutkuje określonymi karami finansowymi. W związku z powyższym istnieje silna potrzeba modernizacji istniejących sieci elektroenergetycznych z wykorzystaniem nowoczesnej aparatury. W artykule przedstawiono innowacyjne, autorskie stanowisko badawcze oparte o tzw. rozbieralną komorę próżniową, które umożliwia przeprowadzenie badań nad poprawą parametrów eksploatacyjnych nowoczesnej aparatury łączeniowej wykorzystywanej w sieciach Smart Grid. Przedstawiono również wyniki badań wytrzymałości elektrycznej przerwy międzystykowej celem potwierdzenia poprawności działania opisanego stanowiska badawczego

Noise-induced synchronization in the Fahy-Hamann model

We study the noise-induced synchronization in a system of particles moving in Fahy–Hamann potential [S. Fahy, D.R. Hamann,Phys.Rev.Lett. 69, 761 (1992)] and subjected to generalized Langevin forces. We investi- gate the synchronization dependence on system’s parameters and on mem- ory range. The results show that while in general memory acts against synchronization, for intermediate memory ranges the opposite effect can be observed. Generally the synchronization transition is found to depend on memory range, temperature and dissipation in the system. PAC

Molecular dynamics simulation of the Lennard-Jones polymers in a good solvent

We carried out united-atom Langevin dynamics simulations of poly- mer’s equilibrium state in a good solvent. Our primary goal was a pedagog- ical exposition of fundamental equilibrium properties of isolated polymers in dilutions with amodel that containsmany features of realmaterials. The polymer was chosen to be a three-dimensional chain of N identical beads (monomers) without internal structure. Each monomer interacted with its two neighbors by a harmonic potential, which modeled a chemical bond. Additionally all monomers within a chain were assumed to interact through the Lennard–Jones (LJ) potential. Interaction with solvent and with other polymers was introduced using Langevin forces. Analyzing internal energy per polymer and radius of gyration as function of temperature we observed a rapid globule to coil phase transition. Also we studied elastic properties of single polymer chain for temperatures below the transition and identified three regions with different elastic behavior. Typical chain lengths in our simulations ranged from 100 to 1000 monomers. The elaborated software package can easily be modified to study e.g. the effect of polymer stiffness on thermodynamic behavior

Software Metrics in Boa Large-Scale Software Mining Infrastructure: Challenges and Solutions

In this paper, we describe our experience implementing some of classic software engineering metrics using Boa - a large-scale software repository mining platform - and its dedicated language. We also aim to take an advantage of the Boa infrastructure to propose new software metrics and to characterize open source projects by software metrics to provide reference values of software metrics based on large number of open source projects. Presented software metrics, well known and proposed in this paper, can be used to build large-scale software defect prediction models. Additionally, we present the obstacles we met while developing metrics, and our analysis can be used to improve Boa in its future releases. The implemented metrics can also be used as a foundation for more complex explorations of open source projects and serve as a guide how to implement software metrics using Boa as the source code of the metrics is freely available to support reproducible research.Comment: Chapter 8 of the book "Software Engineering: Improving Practice through Research" (B. Hnatkowska and M. \'Smia{\l}ek, eds.), pp. 131-146, 201

Phases with splay modulation in a system of hard wedges composed of balls

We studied equilibrium systems composed of wedge-shaped monodisperse molecules using hard-particle Monte Carlo simulations. Each model molecule was built of six co-linear tangent spheres of linearly decreasing diameters. Thus, the shape was unequivocally described by a single parameter $d$: the ratio of the smallest and largest sphere diameters. The phases of the systems were analyzed as a function of $d$ and packing density $\eta$. As interactions were purely of the excluded-volume type, the emergent phases were governed solely by the configurational entropy. For $\eta < 0.5$, apart from the isotropic liquid, we observed standard nematic and smectic A liquid crystalline phases. For $\eta > 0.5$, however, apart from ordinary non-polar hexagonal crystal, two new frustrated polar crystalline phases with splay modulation appeared: antiferroelectric splay crystal ($\text{Cr}_\text{S}\text{P}_\text{A}$) and ferroelectric splay crystal ($\text{Cr}_\text{S}\text{P}_\text{F}$). All configurations were studied in terms of nematic, smectic, and hexatic order parameters, as well as the radial distribution function and the polarization correlation function

Virtual slides: application in pulmonary pathology consultations.

The Virtual Slide (VS) is an interactive microscope emulator that presents a complete digitized tissue section via the Internet. A successful implementation of VS has been observed for educational, research venues and quality control. VS acquisition for consultative pathology is not so common. The purpose of this study was to explore the efficacy and usability of VS in the consultative pulmonary telepathology. 20 lung tumors entered the study. The performance was programmed for 2 medical centers specialized in pulmonary pathology (beginner and advancer in telepathology). A high-quality VSs were prepared by Coolscope (Nikon, Eclipsnet VSL, Japan), and were evaluated via the Internet. The cases were reviewed for the second time with conventional light microscope. VS diagnostic accuracy and the interobserver variability were evaluated. Also the time taken by examiners to render the diagnoses and time needed to scan the microscopic slide were analyzed. Percentage concordance between original glass-slides diagnosis and diagnosis for VSs was very high. Pathologists found the download speed of VSs adequate; experience in telepathology reduced the time of VS diagnosis. VS implementation suggests advantages for teleconsulation and education but also indicate some technical limitations. This is the first Polish trial of VS implementation in telepathology consultative service

Suicidal digoxin intoxication in 61 year old patient

Digoxin is one of the oldest drugs used in cardiology. It belongs to subgroup of cardiac glycosides. Currently, due to limited indications for use, cases of poisoning with this group of drugs are becoming less common. Ease of poisoning results from the low therapeutic index and symptoms of intoxication may include many different systems. The most serious symptoms of overdose are cardiac arrhythmias. We present a case of a patient with suicide poisoning due to ingestion of 30 tablets of 0.1mg digoxin

Wyobraźnia apokaliptyczna w czasach zarazy

Artykuł powstał w szczytowym okresie pandemii koronawirusa w Polsce (choroby COVID-19). Analizuje sytuację poznawczą w czasie epidemii, odwołując się do zagadnień epistemologicznych i metodologicznych. Opisuje kondycję wyobraźni apokaliptycznej i stan dyskursu publicznego na temat apokalipsy. W artykule wykorzystano dwa typy źródeł. Po pierwsze, przeanalizowano próbę celową postapokaliptycznych tekstów kultury popularnej, obejmującą 308 filmów oraz 201 powieści i opowiadań. Po drugie, przebadano folklor internetowy, w tym przede wszystkim memy będące grafikami (zebrane w marcu i kwietniu 2020 r.). Tekst dowodzi, że nie jesteśmy świadkami proliferacji myślenia apokaliptycznego. Użytkownicy Internetu wykorzystują klisze kultury popularnej (czerpane przede wszystkim z dzieł postapokaliptycznych) i posługują się świecką wizją czasu jako nieograniczonego postępu

Conformational degrees of freedom and stability of splay-bend ordering in the limit of a very strong planar anchoring

We study the self-organization of flexible planar trimer particles on a structureless surface. The molecules are made up of two mesogenic units linked by a spacer, all of which are modeled as hard needles of the same length. Each molecule can dynamically adopt two conformational states: an achiral bent-shaped (cis-) and a chiral zigzag (trans-) one. Using constant pressure Monte Carlo simulations and Onsager-type density functional theory (DFT), we show that the system consisting of these molecules exhibits a rich spectrum of (quasi-)liquid crystalline phases. The most interesting observation is the identification of stable smectic splay-bend ($S_{SB}$) and chiral smectic A ($S_A^*$) phases. The $S_{SB}$ phase is also stable in the limit, where only cis-conformers are allowed. The second phase occupying a considerable portion of the phase diagram is $S_A^*$ with chiral layers, where the chirality of the neighboring layers is of opposite sign. The study of the average fractions of the trans- and cis-conformers in various phases shows that while in the isotropic phase all fractions are equally populated, the $S_A^*$ phase is dominated by chiral conformers (zigzag), but the achiral conformers win in the smectic splay-bend phase. To clarify the possibility of stabilization of the nematic splay bend ($N_{SB}$) phase for trimers, the free energy of the $N_{SB}$ and $S_{SB}$ phases is calculated within DFT for the cis-conformers, for densities where simulations show stable $S_{SB}$. It turns out that the $N_{SB}$ phase is unstable away from the phase transition to the nematic phase, and its free energy is always higher than that of $S_{SB}$, down to the transition to the nematic phase, although the difference in free energies becomes extremely small when approaching the transition

Zastosowanie uszypułowanego płata skórno-mięśniowego z mięśnia czworobocznego w leczeniu zaburzenia gojenia rany pooperacyjnej po dwuetapowej stabilizacji kręgosłupa piersiowego – opis przypadku

Musculocutaneous flaps play an important role in modern reconstructive surgery. They are useful in the treatment of primary traumatic skin lesions and secondary lesions formed during complicated healing of the surgical wounds. The case of 60 years old woman undergoing complicated healing of the wound after spine surgery is presented. The patient was qualified to spine surgery due to metastatic tumour caused by the lung cancer. The use of pedicled flap facilitated healing of the wound; thus, there was no need to remove implants stabilising pathologically fractured spine. The issue of ‘reconstructive ladder’ is discussed in the paper with various treatment options. Indications, surgical technique and postoperative care are thoroughly discussed providing an overview on this valuable method of treatment which allows a successful termination of complicated wound healing process.We współczesnej medycynie płaty uszypułowane pełnią ważną rolę, zarówno w leczeniu pierwotnych – urazowych ubytków powłok ciała, jak również wtórnych do leczenia operacyjnego, powikłanych wadliwym gojeniem rany. Poniżej przedstawiamy przypadek 60-letniej kobiety z chorobą nowotworową ze złamaniem patologicznym kręgosłupa i źle gojącą się raną pooperacyjną. Zastosowanie płata uszypułowanego umożliwiło zamknięcie i wygojenie rany, co pozwoliło uniknąć konieczności usunięcia implantów stabilizujących złamany kręgosłup. Artykuł ten dotyka problemu drabiny rekonstrukcyjnej i odpowiada na pytanie, kiedy zastosować jaką metodę leczenia. Mówi o wskazaniach do wykonania zabiegu przeniesienia płata skórno-mięśniowego, postępowaniu okołooperacyjnym oraz opiece pooperacyjnej. Opisuje przydatną metodę leczniczą, której znajomość i umiejętność zastosowania pozwala zakończyć z sukcesem powikłany proces gojenia rany pooperacyjnej