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Project management for the construction sector in the field of foundation of designed residential building located in this area with the expected impact of mining operation
PublicationAutorzy: Gwóźdź-Lasoń Monika, Berski Łukasz.
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USEFULNESS OF SEMI-MARKOV PROCESSES AS MODELS OF THE OPERATION PROCESSES FOR MARINE MAIN ENGINES AND OTHER MACHINES OF SHIP POWER PLANTS
PublicationThe paper describes the properties of semi-Markov processes and the opportunities and benefits from their use as models of the operation processes for marine combustion engines and other machines of ship power plants. The emphasis is put on the importance of the theory of semi-Markov processes for development of the theory of marine combustion engines and other machines of ship power plants, as well as for development of the operational...
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Comparison of the Measurement Techniques Employed for Evaluation of Ambient Air Odour Quality Influenced by Operation of Industrial Sewage Treatment Plant
PublicationThe paper presents the results of investigation on ambient air quality evaluation with respect to concentration of odorants in a vicinity of a sewage treatment plant of the LOTOS Group S.A. petroleum plant. The investigation was performed during winter season using a prototype of electronic nose and the Nasal Ranger field olfactometers. The prototype was equipped with a set of six semiconductor sensors by FIGARO Co. and one PID-type...
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The impact of air humidity on the operation of proton exchange membrane fuel cells determined using dynamic electrochemical impedance spectroscopy
PublicationThis paper describes the changes in the fuel cell impedance across a range of current loads and humidity changes. The changes of each equivalent circuit parameters representing specific processes occurring in fuel cells, as a function of humidity and current changes, were determined. Within the combined scope of current and humidity, the optimal working conditions of the cells were determined, corresponding to the lowest impedance...
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Multi-stage magnetic-fluid seals for operating in water - life test procedure, test stand and research results. Part II Results of life tests of multi-stage magnetic - fluid seal operating in water
PublicationThe edge criteria for magnetic-fluid seals durability research were described in previous article [24] and now the tests results are presented. The tests were made with three magnetic fluids using various magnets quantity in magnetic assemblies. If values obtained in the repeated test deviated by more than 10 % from results of the first test an additional control test was made for final characteristics. The characteristics are:...
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Operational Research in Engineering Sciences: Theory and Applications
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The operating field of a hydrostatic drive system. Parameters of the energy efficiency investigations of pump and hydraulic motors
PublicationPrzedstawiono pole pracy układu napędu hydrostatycznego. Uzasadniono podział parametrów pracy silnika hydraulicznego i pompy na parametry niezależne i zależne od pracy tych maszyn wyporowych i układu z nich utworzonego. Zaproponowano podjęcie tematu badawczego mającego na celu opracowanie metod wyznaczania charakterystyk energetycznych pomp i silników hydraulicznych obrotowych oraz zmodyfikowanych metod wyznaczania charakterystyk...
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Modification of the operating point of residual current transformers for high frequency earth fault currents detection
PublicationFor protection against electric shock in low voltage systems residual current devices are commonly used. However, their proper operation can be interfered when earth fault current with high frequency components occurs. Serious hazard of electrocution exists then. One of the most important element of residual current devices is a residual current transformer with iron core. Tripping characteristic of residual current devices strictly...
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Assessment of Financial Security of SMEs Operating in the Renewable Energy Industry during COVID-19 Pandemic
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Projection framework for hybrid methods derived from finite difference operators in time and frequency domain
PublicationW artykule przedstawiono ogólną koncepcję tworzenia algorytmów hybrydowych na bazie operatorowego sformułowania metody różnic skończonych. Wykorzystano koncepcję projekcji ortogonalnej w przestrzeni skończeniewymiarowej w celu modyfilacji pierwotnego sformułowania.
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Equivalence of equicontinuity concepts for Markov operators derived from a Schur-like property for spaces of measures
PublicationVarious equicontinuity properties for families of Markov operators have been – and still are – used in the study of existence and uniqueness of invariant probability for these operators, and of asymptotic stability. We prove a general result on equivalence of equicontinuity concepts. It allows comparing results in the literature and switching from one view on equicontinuity to another, which is technically convenient in proofs....
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The congruence of mental models in entrepreneurial teams – implications for performance and satisfaction in teams operating in an emerging economy
PublicationPurpose – The paper aims to explore the relationship between the congruence of mental models held by the members of entrepreneurial teams operating in an emerging economy (Poland) and entrepreneurial outcomes (performance and satisfaction). Design/methodology/approach – The data obtained from 18 nascent and 20 established entrepreneurial teams was analysed to answer hypotheses. The research was quantitative and was conducted using...
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Conception of selecting reliability models for taking operating decisionsrelated to sea-going ship´s systems
PublicationPrzedstawiono możliwości podejmowania decyzji dotyczących sytuacji, gdy decydent dysponuje informacją aprioryczną o stanie technicznym urządzeń, na przykład uzyskaną z badań niezawodności urządzeń niezbędnych do wykonania zadania, wyrażoną w formie prawdopodobieństwa. Do opracowania modelu umożliwiającego podejmowanie takich decyzji eksploatacyjnych wykorzystano elementy bayesowskiej statystycznej teorii decyzji.
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Highly stable CsFAPbIBr perovskite solar cells with dominant bulk recombination at real operating temperatures
PublicationMixed-cation mixed-halide perovskite solar cells have been characterized in DC at different temperatures (from −20 °C up to 50 °C) and the time evolution of the device efficiency has been assessed using different degradation protocols (indoors and outdoors). The completely planar p–i–n structure is ITO/CuNiOx/PTAA/CsFAPbIBr/PCBM/PEI/Ag. Pristine current–voltage characteristics barely show hysteresis, at any temperature. Open circuit...
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Limited selectivity of amperometric gas sensors operating in multicomponent gas mixtures and methods of selectivity improvement
PublicationIn recent years, smog and poor air quality have became a growing environmental problem. There is a need to continuously monitor the quality of the air. The lack of selectivity is one of the most important problems limiting the use of gas sensors for this purpose. In this study, the selectivity of six amperometric gas sensors is investigated. First, the sensors were calibrated in order to find a correlation between the concentration...
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Mobile inventory system for hydrotechnical objects using data from multiple sensors operating simultaneously
PublicationThe knowledge of the location, shape and other characteristics of spatial objects in the coastal areas has a significant impact on the functioning of ports, shipyards, and other water-infrastructure facilities, both offshore and inland. Therefore, measurements are taken of the underwater part of the waterside zone, which means the bottom of water and other underwater objects (e.g. breakwaters, docks, etc.), and objects above the...
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Long-term operating conditions for different sorption materials to capture phosphate from domestic wastewater
PublicationThis paper presents the results of a study on the possibility of applying various configured filters filled with a mixture of Rockfos® and Leca® material for the effective capture of phosphate from domestic wastewater. The tests were carried out for two years at two wastewater flow rates (20 and 40 L/day) in three pairs of filtration columns with a volume of filter material equal to 20 liters each. Columns 1A and 1B were filled...
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INVESTIGATION OF THE CHARACTERISTICS OF A LOWEMISSION GAS TURBINE COMBUSTION CHAMBER OPERATING ON A MIXTURE OF NATURAL GAS AND HYDROGEN
PublicationT his article is devoted to the investigation of the characteristics of a low-emission gas turbine combustion chamber, which can be used in Floating Production, Storage and Offloading (FPSO) vessels and operates on a mixture of natural gas and hydrogen. A new approach is proposed for modelling the processes of burning out a mixture of natural gas with hydrogen under preliminary mixing conditions in gaseous fuel with an oxidizer...
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Areas of Fan Research—A Review of the Literature in Terms of Improving Operating Efficiency and Reducing Noise Emissions
PublicationFans as industrial devices are among the most significant single recipients of driving energy. Therefore, they represent an important area of energy savings to reduce CO2 emissions. The ubiquity of fans and their operation under conditions different from the optimum provides an opportunity for more significant global reductions in the energy used to drive them. The second important aspect, besides energy efficiency, related to...
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Electrochemical degradation of textile dyes in a flow reactor: effect of operating conditions and dyes chemical structure
PublicationIn this study, electrochemical oxidation of five azo dyestuffs (Yellow D-5GN, Red D-B8, Ruby F-2B, Blue D-5RN, Black DN), that are widely used in the textile industry, was investigated in a flow reactor. BDD electrode with a high boron doping level (C/B = 10 000) was prepared and used. Two configurations of reactor were considered, i.e., one with the undivided cell, and the other with the cell divided by anodic and cathodic compartments....
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Investigation of the Combustion Processes in the Gas Turbine Module of an FPSO Operating on Associated Gas Conversion Products
PublicationIn this paper, we consider the issue of thermo-chemical heat recovery of waste heat from gas turbine engines for the steam conversion of associated gas for offshore vessels. Current trends in the development of offshore infrastructure are identified, and the composition of power plants for mobile offshore drilling units and FPSO vessels is analyzed. We present the results of a comparison of power-to-volume ratio, power-to-weight...
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Destructiveness of Profits and Outlays Associated with Operation of Offshore Wind Electric Power Plant. Part 1: Identification of a Model and its Components
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Safety Analysis for the Operation Process of Electronic Systems Used Within the Mobile Critical Infrastructure in the Case of Strong Electromagnetic Pulse Impact
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SUDDEN CARDIAC ARREST IN PATIENTS OVER 60 YEARS OF AGE IN THE OPERATION AREA OF EMERGENCY MEDICAL SERVICE IN SIEDLCE IN 2013-2017
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Centrally Pivoted Tilting Pad Thrust Bearing with Carbon-Based Coated Collar—Experimental Results of Low- and Medium-Speed Operation
PublicationExperimental results of the research on a tilting pad thrust bearing with symmetrical pad support in the conditions of high loads and low speeds are presented in the paper. As described in the literature review, experimental results of tilting pad bearings at low speed/high load regime and transient conditions are rare. Unusual material selection - steel pad against a DLC-type coating on the collar was utilized. Such material combination...
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Supporting development of the smart ship technology by CFD simulation of ship behavior in close to real operational conditions
PublicationThe shipping industry is at the milestone of technological development – autonomous ships. Involving smart technologies accelerates development of green and safe shipping. Also IMO regulations, especially EEDI en-hanced application of new technologies. Meeting economic and ecological requirements future ships need to be designed with respect to increased reliability and operational performance. Design process of ships may be improved...
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Modern design solutions of cooling systems, as an example of energy efficiency rationing, operational safety and environmental protection
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Towards an analysis framework for operational risk coupling mode: A case from MASS navigating in restricted waters
PublicationMaritime Autonomous Surface Ships (MASSs) constitute highly interconnected and tightly coupled multistate systems. Incorporating the coupling effects of both interactions and dependencies is centrally important to ensure navigation safety of MASSs. This paper proposes a framework for examining the coupling effects in the operational modes (OM) of MASSs. Failure Modes (FMs) of MASSs related to interactions with the environment and...
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Sustainable nitrogen removal in anammox-mediated systems: Microbial metabolic pathways, operational conditions and mathematical modelling
PublicationAnammox-mediated systems have attracted considerable attention as alternative cost-effective technologies for sustainable nitrogen (N) removal from wastewater. This review comprehensively highlights the importance of understanding microbial metabolism in anammox-mediated systems under crucial operation parameters, indicating the potentially wide applications for the sustainable treatment of N-containing wastewater. The partial...
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Piotr Rajchowski dr inż.
PeoplePiotr Rajchowski (Member, IEEE) was born in Poland, in 1989. He received the E.Eng., M.Sc., and Ph.D. degrees in radio communication from the Gdańsk University of Technology (Gdańsk Tech), Poland, in 2012, 2013, and 2017, respectively. Since 2013, he has been working at the Department of Radiocommunication Systems and Networks, Faculty of Electronics, Telecommunications and Informatics, Gdańsk University of Technology, as a IT...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 85
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a trapezoidal manifold, condenser temperature 90 and evaporator temperature 90
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 70
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a rectangular manifold, condenser temperature 30 and evaporator temperature 90
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a trapezoidal manifold, condenser temperature 70 and evaporator temperature 60
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 95
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 90
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Application of road map of operating condition for estimation of fuel and electric energy consumption from city transport
PublicationThe paper presents procedure of data collecting and generation of road map of operating condition in the selected urban area. This map allows forecasting the selected vehicle operating parameters for the assumed road. The main parameters calculated using the road maps of operating conditions are: total energy spent to drive the selected vehicle, consumed fuel, travel time, average speed of travel, CO2 emissions. Presented example...
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AN IMPACT OF THE EFFICIENT FUNCTIONING OF THE VENTILATION AND AIR-CONDITIONING SYSTEM ON THERMAL COMFORT OF THE MEDICAL STAFF IN THE OPERATING ROOM
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Analysis of cost structure of international road transport operators in West Pomeranian voivodship in the years 2008-2014
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A LUMPED-CIRCUIT MODEL OF CIRCULAR PISTON TRANSDUCER FOR MODELING ITS PERFORMANCE IN DUAL FREQUENCY OPERATING MODES
PublicationThe paper presents novel network equivalent circuit of piezoceramic circular disc transducer that takes into account thickness and ra dial mode of vibrations. The starting point of the analysis is 4-port description of circular disc element representing the solution of wave equation set in radial and thickness directions. Th e approximate solution for harmonic case is represented in the form of 4x4 matrix, which is syn thesized...
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Microstrip line with short-circuited edge as a high-pass filter operating up to millimeter-wave frequencies
PublicationPrzedstawiono prosty planarny filtr górnoprzepustowy wykorzystujący linię mikropaskową ze zwartym brzegiem. Układy zaprojektowano w taki sposób, aby pasmo przepustowe rozpoczynało się w zakresie K lub Ka. Wykonano dwa prototypy: na podłożu w postaci warstwy dielektrycznej wykonanej z ceramiki alundowej oraz na podłożu organicznym o niskiej przenikalności elektrycznej. Wykazano dużą zgodność teoretycznych i pomierzonych charakterystyk...
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Evaluation of the reference fuel consumption and CO2 emission of vehicle with using of the map of operating conditions for selected agglomeration
PublicationZaproponowana w pracy metoda tworzenia mapy warunków eksploatacji dla wybranej aglomeracji może zostać przeprowadzona przy wykorzystaniu tanich i prostych w obsłudze urządzeń. Podstawowym urządzeniem badawczym jest pojazd samochodowy wyposażony w system pomiaru położenia GPS z układem korekty wskazań wysokości i rejestracji parametrów jazdy. Zamieszczony w pracy przykład wykorzystania mapy warunków eksploatacji pokazuje możliwości...
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Zagrożenia środowiska podczas eksploatacji gazociągów podmorskich = Environmental threats during oparation of subsea gas pipelines
PublicationPrzedstawiono wybrane zagadnienia eksploatacji gazociągów podmorskich, w tym zagrożenia dla rekreacyjnego i gospodarczego korzystania z morza. Uszkodzenie gazociągu podmorskiego jest zazwyczaj spowodowane korozją, działaniami morskimi lub zagrożeniami naturalnymi. W określonych warunkach mogą wytrącić się kryształy hydratów węglowodorów gazowych, co może prowadzić do zablokowania linii przesyłowej
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PREDICTION OF SHIP MOTIONS IN IRREGULAR WAVES BASED ON RESPONSE AMPLITUDE OPERATORS EVALUATED EXPERIMENTALLY IN NOISE WAVES
PublicationThe most common methods for predicting ship roll motions in a specified sea state are direct measurements of motions in a representative irregular wave realisation (time domain) or calculations of motions from response amplitude operators (RAOs) in the frequency domain. The result of the first method is valid only for the tested sea state, whilst the second method is more flexible but less accurate. RAO-based predictions are calculated...
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Experimental study on the feasibility of alternative materials for tilting pad thrust bearings operating in transition to mixed friction
PublicationIn hydrodynamic bearings traditional bearing alloys: Babbitts and bronzes are most frequently utilized. Polymer sliding layers are sometimes applied as a valuable alternative. Hard diamond-like carbon (DLC) coatings, which are also considered for certain applications may show some advantages, as well. Although material selection is of secondary importance in a full film lubrication regime it becomes important in mixed friction...
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Examining Impact of Speed Recommendation Algorithm Operating in Autonomous Road Signs on Minimum Distance between Vehicles
PublicationAn approach to a new kind of recommendation system design that suggests safe speed on the road is presented. Real data obtained on roads were used for the simulations. As part of a project related to autonomous road sign development, a number of measurements were carried out on both local roads and expressways. A speed recommendation model was created based on gathered traffic data employing the traffic simulator. Depending on...
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A Method of Fast and Simultaneous Calibration of Many Mobile FMCW Radars Operating in a Network Anti-Drone System
PublicationA market for small drones is developing very fast. They are used for leisure activities and exploited in commercial applications. However, there is a growing concern for accidental or even criminal misuses of these platforms. Dangerous incidents with drones are appearing more often, and have caused many institutions to start thinking about anti-drone solutions. There are many cases when building stationary systems seems to be aimless...
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Derivation of motor mean phase currents in PMSM drives operating with low switching-to-fundamental frequency ratio
PublicationPulse width modulation (PWM) of inverter output voltage causes the waveforms of motor phase cur-rents to consist of distinctive ripples. In order to provide suitable feedback for the motor current con-trollers, the mean value must be extracted from the currents’ waveforms in every PWM cycle. A com-mon solution to derive the mean phase currents is to sample their value at the midpoint of a symmetrical PWM cycle. Using an assumption...
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Innovative Implantable Left Ventricular Assist Device—Performance under Various Resistances and Operating Frequency Conditions
PublicationThis paper presents the operation of an innovative left ventricular assist device under various resistances and operating frequencies. The operating principle of the device is based on pulsatile blood flow, which is forced by a suction–discharge device pumping helium into a set of intra-cardiac balloons. In this way, the ejection fraction of the left ventricle is increased, and the mitral valve is additionally occluded. What is...