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The authors analyzed heat supply systems of rural households and autonomous consumers based on renewable energy sources. The heat-technological scheme of the solar-geothermal heat supply system is proposed based on the existing geothermal energy sources in the natural and climatic conditions of Kashkadarya region. In the research work, the heat capacities, temperature regimes, chemical composition of geothermal water of different geothermal energy sources of Kashkadarya region were studied. As a result of the conducted research, a combined heliogeothermal heat supply system was proposed. It is based on the fact that 14493 kWh or 52176 MJ of thermal energy can be produced during the day through the proposed combined helio-geothermal heat supply system, and 52176/29.31=1780 kg of conventional fuel can be saved during the day when geothermal source heat is used. As a result, 2000-3000 kg of conventional fuel savings can be achieved in one year, according to heat-technical calculations. [ABSTRACT FROM AUTHOR]

This paper proposes an e-voting system for liquid democracy based on the Ethereum blockchain technology. The proposed system aims to increase the transparency, security, and efficiency of voting processes by using smart contracts and blockchain technology. The system will allow voters to vote and delegate power to trusted representatives, who in turn can delegate their votes to other representatives, creating a dynamic and flexible voting ecosystem. The system will also provide several benefits, including increased accessibility, transparency, and security of the voting process, reducing the risk of tampering and fraud. This paper concludes that an Ethereum blockchain-equipped e-voting system for liquid democracy is a promising solution for improving the transparency, security, and efficiency of voting processes. [ABSTRACT FROM AUTHOR]

Patients admitted with heart failure facing a high risk of mortality where 30-day mortality rates are reaching 10%. Identifying patients with high and low risk of mortality could improve clinical outcomes and hospital resource allocation. Existing mortality predictors use statistical and mathematical models that are difficult to obtain where it requires the researcher to understand the relationship between variables that exist in the models. Furthermore, the statistical model consumes a lot of time to build it and it requires experts and requires a lot of effort to build such models. As an alternative approach, machine learning techniques have become very popular to solve problems for forecasting and predictions. This paper proposed the use of machine learning to predict mortality for heart failure patients. Results shows that machine learning techniques able to produce good prediction accuracy. Support Vector Machine produces the best prediction accuracy which test dataset accuracy is at 85% and overall prediction accuracy is at 86.67% [ABSTRACT FROM AUTHOR]

The article presents the calculated data for determining the geometric and kinematic parameters of the developed chain transmission for the 2SB-10 cotton dryer. The chain transmission scheme and the chain pitch are selected, according to which other parameters of the chain transmission are determined. The given calculation data are necessary for the manufacture and assembly of the developed chain transmission for the 2SB-10 drum dryer. The number of teeth of the smaller sprocket is chosen to be 18 pcs. A value has been developed for determining the rotation speed of the driving sprocket, based on the fact that the required rotation speed of the driven sprocket (drum dryer) will be selected within 10 rpm. The approximate optimal center distance of the chain drive is selected depending on the chain pitch t, usually within: a≥ (30÷50) t (smaller values for small gear ratios). The minimum center distance "a tip" of the chain transmission is taken depending on the gear ratio "and" of the transmission and the condition that the angle of wrapping of the chain of the smaller sprocket is at least 120 °, i.e. with u>3. [ABSTRACT FROM AUTHOR]

In the current period, the solar energy system has become the most important source of renewable energy, such as wind, fuel cells, and others. The need for it has increased greatly, so that it is relied upon in many services, industrial and agricultural fields, etc. With the increase in demand for solar energy, it leads us to develop and increase its efficiency and improve its performance in various ways. One of these ways is the interest in the monitoring system, which has received great attention from researchers and designers recently. Wireless monitoring systems have been linked with photovoltaic systems and display them on a platform in a more clear and easy way for the user. The design and implementation of a wireless data acquisition system for a photovoltaic panel system is discussed in this paper. based on the ATmega328P microcontroller integrated with the Arduino Uno board, In the proposed monitoring system, the Bluetooth technology was relied on to receive the values of the variables or parameters to be measured by the sensors that were previously determined, namely temperature, humidity, solar radiation, voltage, current, and power, and then display the results taken on smart phones and tablets running Android operating systems using the APK application. The proposed system is characterized by its low cost, simple design, open source, real-time measurement, developable, efficient, high accuracy, reliable, and practical. [ABSTRACT FROM AUTHOR]

Gelatin is a protein derivative product obtained from the partial hydrolysis of collagen, which has various applications in food, pharmaceutical, cosmetic, photography, and other industries. The primary source of gelatin is pork skin. Other sources of gelatin bones and skins of cows and chickens. All have halal-related issues and may cause allergies and other health problems. An alternative source of gelatin is fishbone. However, the conventional methods for extracting fish gelatin have low production efficiency, which limits industrial yields and requires large amounts of water and chemical solvents that generate hazardous waste for the environment. This research explores hydrothermal extraction as an alternative method for gelatin production. This method does not require a lot of chemical solvents and water during the process and thus offers a greener or more sustainable process for gelatin production. Different yields of gelatin were obtained for different fish species: Pangasius hypophthalmus, Oreochromis mossambicus, and Clarias gariepinus. Further process improvement must be conducted before the process can be commercially applied. [ABSTRACT FROM AUTHOR]

Terrace houses in Malaysia dominate the housing typology since the 1960s and remain popular among homebuyers until now. Petaling Jaya is an old town that directed the growth of terrace houses in its early development resulting in a soaring number of housing typologies in the city. Refurbishment has become a widespread trend among the building owners in PJ due to the ageing condition of the terrace houses. Therefore, this paper aims to identify the rate of refurbishment behaviours among the terrace houses in SS5, Kelana Jaya. The research adopts a qualitative approach through case observational studies of the double-story terrace houses in the whole area of SS5 Kelana Jaya, PJ. The sampling focuses on the intermediate units of double-story terrace houses to evaluate the cases within the same baseline. Findings indicate that 354 units out of 400 terrace houses have performed refurbishment, representing almost 40% of the typology. It validates that the refurbishment rate of the double-story terrace house in SS5 Kelana Jaya is very high. Thus, this concludes that the refurbishment behaviour in the SS5 Kelana Jaya area is critical, and further studies advocating sustainability insights into the refurbishment works will be highly prospective. [ABSTRACT FROM AUTHOR]

Detecting carcinogen N-nitrosodimethylamine (NDMA) in Zantac® products led to recalls in 2019–2020; however, considering its bioavailability, the effect of human gastrointestinal system on it has not been estimated for human health risk assessment. NDMA bioavailability depends on Zantac® physicochemical properties, chemical (lipid solubility and pH), and biological processes. In this study, two brands of Zantac®, GlotacTM® 150 mg, and Ortac® 150 mg were chosen, and the bioavailability of NDMA was determined by the first time approached, (Bioaccessibility Research Group of Europe). BARGE The aims were: to compare the results of NDMA, ranitidine, tablet film coatings, and titanium bioavailabilities against the cancer danger estimation recommended daily consuming borders; to explore whether the regular intake of Zantac® is safe for intake or not. Total and bioaccessible concentrations of NDMA, ranitidine, and titanium were determined by Gas chromatography mass spectrometry (GC-MS), UV-Visible spectrophotometer and Inductively Coupled Plasma Optical Emission spectroscopy (ICP-OES), respectively. The limit of detection (LOD) and recovery for the instruments was established, and analytical chemistry for the BARGE UBM was certified using soil, British Geological Survey (BGS-102). The results showed NDMA and titanium have the greatest bioaccessible values in the gastric phase. In contrast, the values for ranitidine are much lower and higher in the gastrointestinal phase, with no differences between the two brands of Zantac® observed. The acceptable daily intake limits for NDMA and ranitidine were below their safe threshold levels, while titanium exceeded them. In conclusion, this approach demonstrated that the BARGE method could be used to determine the bioaccessible concentration and bioaccessible fraction of chemical composition in Zantac®. NDMA and ranitidine are safe for regular intake, while titanium can cause health risk for humans. [ABSTRACT FROM AUTHOR]

This article provides information on determination of energy performance in laboratory-field tests of wide-width sowing machine-tractor aggregate. In this case, experiments to determine the traction resistance of the aggregate in operating process and in idle mode were determined by the towing method. The traction resistance of the MTA (Machine-Tractor Aggregate) and tractor was determined. As a result, daily productivity of Magnum 8940 + Case 1200 aggregate was 41.82 hectares, the main time during the shift was 3.87 hours, and a time of one shift was 8.2 hours. [ABSTRACT FROM AUTHOR]

The article presents results of the impact of machine-tractor unit (MTU) undercarriages during soil cultivation and cultivation of agricultural crops. With movement of row-crop units across the field, MTU propellers repeatedly compact the soil. This negatively affects production of seedlings, the growth and development of plants, as well as yield of agricultural crops. In this regard, these studies are purposed at determining compaction effects on soil and conducting an agroecological assessment of the undercarriages of existing MTUs, studying soil compaction under influence of general-purpose caterpillar and wheeled tractors during pre-sowing soil cultivation and its effect on the quality of seedlings, the growth and development of plants; and the yield of cotton. Depending on the zone, technological operations were carried out, preceding sowing, early spring harrowing of the plow in order to close the moisture, chiseling soil after leaching irrigation or chiseling the plow after winter spare irrigation, spring plowing with subsequent smalling, leveling, etc. Expertise of wheeled and tracked agricultural MTUs on soil according to the criterion: vertical force acting on wheel, consisting of weight of the machine and external forces (mounted unit for soil cultivation, etc.). The vertical force is transferred to the soil by contact surface formed between the wheel and the soil. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study of the thermoconvective effects induced by the presence of two inverted trapezoidal isothermal blocks of height h and width l = 0.109, in an annular space confined between two isothermal coaxial horizontal cylinders filled with air, Pr = 0.7, and of radii ratio, R = 2. This investigation gives an accurate description of the influence of the height of blocks on the flow pattern and on the average heat transfer rate, Nug, for a range of Rayleigh numbers Ra up to 104 and for an angular position of blocks φm = 0.82π. The steady solutions obtained are either uni- or bi-cellular flows. A critical height hc,a is determined, characterizing the appearance of the bicellular flow. The numerical study identified a heat transfer enhancement strategy by properly selecting adequate heating block heights. In particular, it appears that increasing h for a given Rayleigh number does not always lead to better heat transfer rates. [ABSTRACT FROM AUTHOR]

The quality of theoretical and practical training for students in Medical Physics needs significant improvements in Romania in order to prevent possible accidents that may occur because of graduates' lack of skills and experience [1]. From this point of view, faculties of physics have a moral duty to deliver graduates capable of facing challenges encountered in practical experience on some very expensive equipment and clinical expertise, dealing with patients, as part of a medical team. A better communication between faculties of physics about finding some creative solutions to recover the existent gap, in accordance with international standards, might be beneficial for all parts involved in Romanian Medical Physics education. The aim of this paper is to propose some simple laboratory activities, using a toy computed tomography, contrast medium, a Markus camera and an electrometer that might contribute to a better Medical Physics students' comprehension of the biological effects of ionization radiation on beans [2-3]. It has been investigated how the germination and survival of the bean samples are affected by X-ray and contrast medium by comparison with a control sample. [ABSTRACT FROM AUTHOR]

The significant advances in diagnostic imaging have resulted in a better ability to define the target volumes in radiation oncology, therapeutic effectiveness being related to correct staging of cancer [1-2]. Computed tomography (CT) is one of the most important and used technology that gives us valuable views inside if the human body [3]. Based on molecular biology, positron emission tomography (PET) is a highly sensitive and accurate nuclear medicine imaging technology and it can be used to improve radiotherapy planning, being able to compare normal and abnormal tissues at a functional, rather than morphological level [4]. We herein describe the case of a patient, diagnosed with stage III. A left breast carcinoma, in which the interdisciplinary medical imaging, molecular and functional, (PET-CT and CT), resulted in a better radiotherapy treatment planning. [ABSTRACT FROM AUTHOR]

Clear-Air Craiova was a volunteering project, successfully implemented in 2020, in Craiova city. Within this project, an independent network of 13 sensors for air quality monitoring and an awareness campaign were developed. Clear Air Oltenia is a natural continuation in 2021 of the previous project, Clear Air Craiova, expanding the network of sensors throughout SW region of Romania. The results of these projects emphasize the role of academic-community cooperation and knowledge transfer toward the general public, opening opportunities for further initiatives of public engagement as a part of the sustainable development of each community. We present an overview of the measurements derived from the independent sensors network installed in Craiova within the project. The data, which regards in particular measurements of PM10 concentration levels, is provided by 7 sensors which are representative for covering Craiova city, with measurement starting around 9 December 2020 and up to 22 Sept. 2021. We highlight cases with higher pollution levels, following the new concentration thresholds recommended by World Health Organization (WHO). [ABSTRACT FROM AUTHOR]

This study was related to the application of biogas digester technology for environmental empowerment and energy independence of rural communities. The study's purpose is to determine the strategies for community empowerment through the utilization of livestock waste into biogas and biofertilizer. The PRA (Participatory Rural Appraisal) method was used who facilitate the community to develop an action plan. SWOT analysis was used to identify strengths, weaknesses, opportunities, and threats. To determine the priority strategy to be carried out, the Analytical Hierarchy Process (AHP) method was used which is basically a method for choosing an alternative. Based on the SWOT analysis, 8 (eight) alternative strategies were formulated, including (1) optimizing human resources, (2) increasing the biogas utilization to support business needs (3) increasing capital assistance for biogas installations either from the government and private companies through corporate CSR funds, (4) development of biogas installations so that smaller in size, more practical in processing and cheaper in price, (5) effective development of sustainable farmer groups, (6) improve the management of cowshed maintenance and livestock health, (7) enforcement of regulations on environmental management, (8) increase socialization about the benefits, constraints of biogas technology, and the importance of protecting the environment. Based on the results of AHP data processing, there are 3 (three) strategies with the highest weight, namely effective development of sustainable farmer groups, the development of biogas installations so that it is more practical, cheap, and efficient and increasing capital assistance for the installation of biogas installations. [ABSTRACT FROM AUTHOR]

Naturally, oil production will decrease so that the Enhanced Oil Recovery (EOR) method is needed. The goal of EOR is to increase oil production, That previously could not be produced. The EOR method is divided into 5: Unmixed Injection, Mixed Injection, Chemical Injection, Heat Injection (Thermal), and Microbial Enhanced Oil Recovery (MEOR). This study discusses EOR CO2 injection. The mechanism of CO2 injection is to expand oil (oil swelling), reduce viscosity and density, reduce interfacial tension. Therefore, it is necessary to research Minimum Miscible Pressure (MMP) to determine where the CO2 injection pressure can be mixed into the hydrocarbon reservoir and vice versa, if it does not reach that pressure, it becomes an unmixed injection. Due to the absence of MMP laboratory results, the researchers used several correlations from journals to obtain the MMP value. In addition,the researchers used Yuan, Glasso, Khazam, to strengthen the results, so the results from the MMP calculations should not be much different. The research use simulator eclipse to help study. The results of this study from several slug size and composition of immiscible CO2 injection with an additional 10 LPG found not much difference between CO2 injection with LPG and without LPG. [ABSTRACT FROM AUTHOR]

Outcome based education (OBE) is upcoming system in the fields of education in present era. Assessment in OBE is important task to measure the performance of each course outcome of the course. The Performance indicators and the specific rubrics also plays important role in tracing the exact cause of failure of the outcomes. Reflection on failure course outcome and action item to improve the performance of the students on the respective course outcome by applying the different teaching technique is challenging task. In this research work the performance of the students in mechanical engineering course Machine Design-II (ME 413), Automatic Control (ME 415) and Mechanical Vibrations (ME 317) is assessed. The mechanical vibration is chosen as a sample course to design the process of identifying the failure cause and implement the different teaching techniques to close the action item with improved results of the failed course outcomes. The EvalTool is used to generate the mapping of course outcome, performance indicators and ABET students' outcomes and FCAR (Faculty Course Assessment Report) to identify the failure cause of the performance of course outcomes of students on each course-outcome of the course which is generated electronically. It is observed that the failure course outcome can be easily traced and by implementing the action items (defer action items) the students' performance is improved. The average value of EAMU increased from 2.44 to 3.57 in the term 391 and further 4.52 in.the term 411 and the student's evaluation in the term 391 was 69% and student's evaluation to the self-evaluation is 89.64%. Whereas, in the term 411 student's response rate is 57.14% and self-evaluation to the student's response is 105.55%. The student's evaluation increased around 16% by changing the teaching techniques. [ABSTRACT FROM AUTHOR]

Renewable energy generation is becoming more popular in recent years. The most important part of this energy system is the DC-AC power converter. There are many types of power converters. Since the PV system supplies multiple DC sources from solar cells, the suitable type that's used in the PV system is the Multilevel Converters (MLCs). Another advantage of using MLC is that it gives a rated output voltage without using step-up transformers as well. Total Harmonic Distortion (THD) of the terminal voltage and load current decreases without using the PWM technique, because the output is in stairway form as compared with the traditional single stage square wave converter that has a high THD. This paper focuses on the cascaded Multilevel-DC Link (ML-DCL) converter-case study (seven levels) modeling, simulation, and practical implementation. As compared with the traditional types of MLCs, the ML-DCL converter can considerably decrease the number of power semiconductor switches, especially when the voltage levels increase to more than five. Simulation results using MATLAB Simulink are presented to confirm the performance of the cascaded ML-DCL converter and then experimentally validated using the Arduino board and the prototype circuit. [ABSTRACT FROM AUTHOR]

The observance of ultramodern developments in view, amalgamation digital, and physical systems will be convincing to a revolution. Universities are required to add to their approach and methods of educations. The latest technologies such as Artificial Intelligence, Cloud Computing, Big Data Analytics, Internet of Thing, Augmented Reality and other advancements need to be the focus for a student to learning its application. This paper based on qualitative research provided by deductive process with an approach focused on curriculum redesigning and teaching the practice in lines with Industrial Revolution 4.0 practices. This research is performed to analyze the dominant aspect of Industrial Revolution 4.0 and highlight the focused areas to be studied by universities while updating and designing their inline curriculum with a revolution upcoming. Based is upon the above-contented analysis and after evaluating terminologies, a curriculum must fulfill proposed an analysis of big data, augmented reality, internet of thing, artificial intelligence, and cloud computing. [ABSTRACT FROM AUTHOR]

The sophisticated of technology make easy and fast while transfering or saving digital information. There are so many techniques to encrypt data, especially digital image. The algorithm that be use in usually need a long time, although the data was goodly encrypted. But there is better if the encryption time faster with good security. Chaos function can make that possible. Logistic map and Bernoulli map is two of chaos function that can be used on cryptography. This paper will develop new chaotic map, that is composition of Bernoulli map and logistic map, (Bernoulli logistic map) and describe about algorithm digital image encryption using that map. The key sensitivity achieve 10−18 and key space of this algorithm is [(231−1)−b×k×d]×1.6×10634, by b, k, d are measure of row, column, and dimension of the image. It makes hard to break this algorithm by bruteforce attack. Based on test by National Institute of Standards and Technologies (NIST) test, the keystream produced shown to be random. The distribution of pixel intensities is uniform. Moreover, the original digital image and the decrypted digital image from this algorithm is same by PSNR value is ∞. [ABSTRACT FROM AUTHOR]

The properties and characteristics of test signals used in constructing the high definition TV (HDTV) and ultra-high definition TV (UHDTV) become an essential task. The proposal was made for the properties and different parameters of tool signals. These properties were considered very important to estimate. the spatial two-dimensional transfer function of frequency modulation through the light path of test signals. Some work was also performed to measure the resolution of the signal transmission and the end device. [ABSTRACT FROM AUTHOR]

The Covid-19 pandemic outbreak is still not over. Even today, there are many cases of people without symptoms (OTG=Orang Tanpa Gejala/People Without Symptoms). The sufferer does not feel the symptoms of fever, cough and runny nose. Patients can still do activities as usual, but suddenly experience shortness of breath and decreased consciousness due to lack of oxygen. This phenomenon of reducing the amount of oxygen in the body without causing symptoms is known as happy hypoxia. This study aims to design a prototype measurement of blood oxygen saturation (SpO2) as an early detection of happy hypoxia in Covid-19 patients using a pulse oximeter sensor and non-invasive methods (without surgery). The sensor is placed on the patient's fingertip and will measure the intensity of light that penetrates the bloodstream at the fingertip. The measurement data is compared with an oximeter and this tool has the highest error of 0.02% and the lowest 0.01%. [ABSTRACT FROM AUTHOR]

Let f: X→X be a continuous map, when a space X is compact with metricd. We prove that if the map f is n-bi-shadowing then it is bi-shadowing and n-expansive, the converse is true for bi-shadowing with respect to a set C(X) which is consist of continuous n-expansive maps. We conclude that the map f is unique bi-shadowing if and only if it is bs-limit bi-shadowing and expansive. We use the results above to prove the following: the map f is unique bi-shadowing if and only if it is unique bs-limit bi-shadowing. Finally, we prove that: if a homeomorphism map f is unique bi- shadowing then it is topologically stable. [ABSTRACT FROM AUTHOR]

A comparison between the relative distribution of the mass density aerosol phase of aerodispersed systems of limited volume (aerosols of high concentration) and the relative distribution of the densities of some liquids was made in this work. The array of data used for the aerosols, was obtained in an experimental setup based on laser light scattering. The data used for the liquids was taken from the reference literature. The collected data for the aerosols are approximated with Gaussian distributions and presented graphically. The applied statistical analysis showed good similarity between the relative distribution of mass densities of the studied aerodispersed systems and that of the taken liquids. [ABSTRACT FROM AUTHOR]

Toxic liver damage was modeled by a single intraperitoneal injection of carbon tetrachloride (CCl4) dissolved in olive oil at a dose of 50 mg/100 g body weight. Modulation of macrophage activity by phthalhydrazide (APH) during CCl4-induced liver injury leads to an increase of mitotically dividing hepatocytes and promotes more rapid normalization of the concentration of stem cell factor (SCF) in the plasma. [ABSTRACT FROM AUTHOR]