Analiza porównawcza wybranych zagadnień programowania wymagających komunikacji międzyprocesowej i międzywątkowej

The following article presents a comparison of multithread and multiprocess communication and synchronization. The theoretical comparison was supported by the solutions of practical, classical synchronization problems. The availability of communication and synchronization mechanisms in the Boost library and in IPC interprocess communication was compared.A subjective assessment of the difficulty in implementation and applications performance was also presented.Poniższy artykuł przedstawia porównanie mechanizmów komunikacji i synchronizacji oferowanych w aplikacjach wielowątkowych oraz analogicznych rozwiązań opartych o komunikację międzyprocesową. Porównanie teoretyczne zestawiono z praktycznymi klasycznymi problemami synchronizacji. Porównano dostępność mechanizmów komunikacji i synchronizacji w bibliotece Boost i w komunikacji międzyprocesowej IPC. Przedstawiono subiektywną ocenę stopnia trudności implementacji i porównanie wydajności

Indicative method of human failure in sustainable chain of custody management

PURPOSE: The purpose is for the action chain (AC) of sustainable management (SM) by monitoring the failure rates of the operator of technical devices and presentation of the results of selected validation of the developed method.DESIGN/METHODOLOGY/APPROACH: The presented method focuses on the monitoring and assessment of the organization’s state, diagnosis of the causes of deviations from the operator's desired state and modeling the state of the system as a result of the planned implementation of ergonomic interventions (IE). Measuring the operator's reaction creates knowledge about the interaction and possibilities of modifying the system thanks to objective data.FINDINGS: The presented method allows to characterize the working environment (including employee workload) with the values of variables which constitute fuzzy cognitive maps (FCM) concepts. The state of the interaction process is determined by potential distractors, which include, inter alia, factors of the work environment, conditions of cognitive and decision-making processes, conditions of manual activities and personality traits.PRACTICAL IMPLICATIONS: The implementation of the indicator method enables the assessment of the potential of IE, which may prove to be a threat to safety, task efficiency and convenience.ORIGINALITY/VALUE: The use of monitoring techniques and the analysis of operator loads and reliability in Industry 4.0 (I4.0) is possible in real time, when registering psychophysiological indicators for the so-called User experience (UX).This work was supported by the Faculty of Management Engineering at the Poznan University of Technology. This article was prepared as part of the project [grant number 0811/SBAD/1036].peer-reviewe

From red to green luminescence via surface functionalization. Effect of 2-(5-mercaptothien-2-yl)-8-(thien-2-yl)-5-hexylthieno[3,4-c]pyrrole-4,6-dione ligands on the photoluminescence of alloyed Ag-In-Zn-S nanocrystals

A semiconducting molecule containing a thiol anchor group, namely 2-(5-mercaptothien-2-yl)-8-(thien-2-yl)-5-hexylthieno- [3,4-c]pyrrole-4,6-dione (abbreviated as D-A-D-SH), was designed, synthesized, and used as a ligand in nonstoichiometric quaternary nanocrystals of composition Ag1.0In3.1Zn1.0S4.0(S6.1) to give an inorganic/organic hybrid. Detailed NMR studies indicate that D-AD- SH ligands are present in two coordination spheres in the organic part of the hybrid: (i) inner in which the ligand molecules form direct bonds with the nanocrystal surface and (ii) outer in which the ligand molecules do not form direct bonds with the inorganic core. Exchange of the initial ligands (stearic acid and 1-aminooctadecane) for D-A-DSH induces a distinct change of the photoluminescence. Efficient red luminescence of nanocrystals capped with initial ligands (λmax = 720 nm, quantum yield = 67%) is totally quenched and green luminescence characteristic of the ligand appears (λmax = 508 nm, quantum yield = 10%). This change of the photoluminescence mechanism can be clarified by a combination of electrochemical and spectroscopic investigations. It can be demonstrated by cyclic voltammetry that new states appear in the hybrid as a consequence of D-A-D-SH binding to the nanocrystals surface. These states are located below the nanocrystal LUMO and above its HOMO, respectively. They are concurrent to deeper donor and acceptor states governing the red luminescence. As a result, energy transfer from the nanocrystal HOMO and LUMO levels to the ligand states takes place, leading to effective quenching of the red luminescence and appearance of the green one

Comparative analysis of selected programming issues requiring inter-process and inter-thread communication

Poniższy artykuł przedstawia porównanie mechanizmów komunikacji i synchronizacji oferowanych w aplikacjach wielowątkowych oraz analogicznych rozwiązań opartych o komunikację międzyprocesową. Porównanie teoretyczne zestawiono z praktycznymi klasycznymi problemami synchronizacji. Porównano dostępność mechanizmów komunikacji i synchronizacji w bibliotece Boost i w komunikacji międzyprocesowej IPC. Przedstawiono subiektywną ocenę stopnia trudności implementacji i porównanie wydajności.The following article presents a comparison of multithread and multiprocess communication and synchronization. The theoretical comparison was supported by the solutions of practical, classical synchronization problems. The availability of communication and synchronization mechanisms in the Boost library and in IPC interprocess communication was compared.A subjective assessment of the difficulty in implementation and applications performance was also presented

Applications of Carbon in Rechargeable Electrochemical Power Sources: A Review

Rechargeable power sources are an essential element of large-scale energy systems based on renewable energy sources. One of the major challenges in rechargeable battery research is the development of electrode materials with good performance and low cost. Carbon-based materials have a wide range of properties, high electrical conductivity, and overall stability during cycling, making them suitable materials for batteries, including stationary and large-scale systems. This review summarizes the latest progress on materials based on elemental carbon for modern rechargeable electrochemical power sources, such as commonly used lead–acid and lithium-ion batteries. Use of carbon in promising technologies (lithium–sulfur, sodium-ion batteries, and supercapacitors) is also described. Carbon is a key element leading to more efficient energy storage in these power sources. The applications, modifications, possible bio-sources, and basic properties of carbon materials, as well as recent developments, are described in detail. Carbon materials presented in the review include nanomaterials (e.g., nanotubes, graphene) and composite materials with metals and their compounds

Ergonomics criteria for control devices used by the elderly working with a computer

W artykule przedstawiono wpływ cech myszy komputerowych na występowanie błędów wpływających na organizację i wykonywanie pracy. Porównano liczbę występujących błędów, czas wykonania zadania i dokładność sterowania, biorąc pod uwagę dziewięć peryferyjnych urządzeń sterowniczych i wybrane osoby starsze. Zaobserwowano związek między liczbą występujących błędów a cechami urządzeń i ich użytkowników; zauważono duży zakres zmian liczby błędów. Na podstawie analizy wyników wykazano, że zadania wykonywano najdłużej z użyciem myszy o najwyższym i najniższym ocenionym poziomie ergonomiczności. Myszy ocenione jako średnio i przeciętnie ergonomiczne najlepiej nadają się do szybkiej pracy. Ocena ergonomiczności badanych myszy, dokonana za pomocą testu Fittsa, znacznie pokrywa się z oceną liczby błędów podczas interakcji.The paper assesses the impact of morphological features of computer mice on the occurrence of unreliability. A comparison of the number of unreliable cases, the duration of the executed control task and control accuracy for nine various mice and three test subjects is presented in this paper. Conclusions: Particular assessment results, according to a person’s execution time for a particular task and the number of unreliable interactions, do not demonstrate a relationship. Whereas, a relationship was demonstrated in the number of occurring unreliable cases, where rises and falls in the occurrence of unreliable cases were observed. The analysis of results demonstrated that tasks using a mouse with the highest and the lowest ergonomic level took the longest to perform. The mice assessed as moderately ergonomic were the best for quick work. An assessment of the ergonomics criteria that the tested mice fulfil, applying the Fitts’ Law test, is convergent with the analysis of the number of cases of unreliable interactions