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Saat ini, isu penggunaan energi yang berlebihan telah mewabah di masyarakat. Penggunaan energi yang berlebihan banyak ditemukan pada lingkungan rumah tangga. Penerapan rumah yang hemat energi dapat dijadikan solusi dalam mengatasi masalah tersebut. Namun, beberapa masyarakat tidak memprioritaskan konsep tersebut. Penelitian ini dimaksudkan untuk menentukan bagaimana persepsi masyarakat mengenai kepentingan menerapkan konsep rumah hemat energi pada rumah tinggal sehari – hari dan menentukan hal – hal yang perlu diperhatikan dalam menciptakan konsep rumah hemat energi. Metode pengumpulan data dilakukan melalui kuesioner ke beberapa responden lapisan masyarakat baik itu karyawan, wiraswasta, maupun mahasiswa. Data yang telah terkumpul dianalisis menggunakan analisis kualitatif data teks. Hasil dari analisis tersebut akan menghasilkan faktor – faktor yang menjadi alasan kepentingan menerapkan konsep rumah hemat energi dan kriteria dalam penerapan rumah hemat energi.

This paper studies the coordinated use of smart inverters with legacy voltage regulating devices to help increase the energy savings from conservation voltage reduction (CVR) in distribution systems with high photovoltaic penetration. Two voltage optimization algorithms are developed to evaluate the CVR benefit by considering two types of smart inverter functions: aggregated reactive power control and autonomous volt/VAR control. In each algorithm, smart inverters are coordinately controlled with the operation of legacy voltage regulating devices including load tap changers and capacitor banks. Both algorithms are tested on representative utility distribution system models. Simulation results demonstrate that the proposed algorithms can achieve around 1.8-3.6% energy savings when only using legacy voltage regulating devices and an additional 0.3-0.9% when adding smart inverters.

Gas hydrates are regarded as one of the most promising alternative sources of energy, which have the potential to address the energy demand of a contemporary society. Based on the field explorations in the Eastern Nankai Trough (Japan), a multilayered hydrate reservoir model has been conceptualised and its behaviours during depressurisation production are simulated. This model incorporates the effects of the initial reservoir temperature and permeability on the mechanism of hydrate dissociation, which in turn affects the gas production. It is shown that the dissociation process is largely affected by the initial temperature distribution within the reservoir layers, and the ‘warmer’ reservoirs show (consistently) higher production potential. Furthermore, the gas production could be improved significantly, by increasing the permeability of the wellbore region, which can be achieved through the fracturing process. The close match between the simulation results and the field tests is noteworthy. The proposed multilayered model would be quite useful for analysing the efficacy of the ‘production strategy’, in most real-life situations.

The impact of gas hydrate dissociation on submarine landslides has become an increasingly significant issue. However, previous models cannot interpret the newly discovered non-conformity between the slide surface and the base of the gas hydrate stability zone. Here, the authors design an experimental approach for visualising fluid migration during hydrate dissociation at atmospheric pressure. The results identify the lateral and vertical fluid migration pathways. Weak layers propagate nearly laterally beyond the hydrate zone, which lengthens the potential slide surface. Vertical pathways branch and deviate from their original paths, generating a shallower slide surface. Furthermore, the findings show that fluid overpressure under the overlying layer leads to steepening slopes. The lubrication effect and the underestimated inclination of slopes at failure may account for the low-angle failure of clay slopes. The results support a new conceptual model that reconciles the non-conformity between the slide surface and the base of the gas hydrate stability zone and offer a new perspective for the large-scale failure of low-angle submarine slopes. It will be interesting and important to confirm these implications in the future.

Displacement has marked the individual and collective lives of Puerto Ricans in Chicago, especially those who migrated in the 1950s and 1960s. For these older persons, the arrival of the gentry and the yuppies of yesterday, the hipsters of today, and the disappearance of familiar faces in their current neighborhoods are not new phenomena, but rather parts of a profoundly familiar process. They came of age in displacement. Today some Puerto Rican older adults have achieved housing security and are able to age in place because they live in low-income senior housing. Yet a sense of displacement still looms large in their daily lives with the upscaling of and new-build gentrification in their current neighborhood. This work sheds light on the meaning of place for older adult Puerto Ricans who have experienced what psychiatrist and urban studies scholar Mindy T. Fullilove calls a history of “serial displacement.” Through life history narratives and ethnographic snapshots, this paper highlights the neglected reality of “aging in displacement,” or the experience of growing up and growing older in a context of repeated socio-spatial dislocation and how individual and collective life histories of community upheaval texture the spatial and social meanings of place.

The interrelationship between rural, rurality and social innovation still remains underexplored even though there has been considerable work within the individual discourses of social innovation and rural studies. This paper aims at broadening the scope of this interrelationship by exploring the nuanced dynamics and complexities of rural lifeworld and the experiences and knowledges of actors that shape the understanding of rural social innovation. At the core of this analysis lies two key ideas including a) an understanding that rural groups' and communities' complexities and marginalities might not be adequately understood without addressing the complex ways in which identities of caste, race, gender, ethnicity and class intersect and b) that the locally-rooted solutions resulting from these concerns are usually underrepresented in the social innovation literature and the relevance of the same needs to be recognized. This reimagining of rural social innovation is located within the theoretical perspectives of intersectionality and feminist perspective and the epistemologies of the South focusing on ‘ecologies of knowledges’ that are capable of complexifying and adding to the contemporary debates on social innovation. From an understanding of the above, the authors argue that strategies and innovations grounded on the specific groups' and communities' own knowledge and rhythm within complex rural contexts needs be recognized as social innovation.

Rural social enterprises are increasingly recognized as organisations that contribute to local development by providing goods and/or services to meet community needs and by fostering inclusive social and governance relations. The purpose of this paper is to explore how rural social enterprises engage in a plurality of socio-economic relations with different dimensions of their ‘place’ when contributing to the development of their localities. Based on three in-depth case studies of social enterprises operating in rural Ireland, our findings illustrate how rural social enterprises engage with locational, institutional, material and identity aspects of their ‘place’, which indicates their ‘placial embeddedness’. Moreover, our findings also demonstrate how these organisations engage in, and combine market, redistribution and reciprocity relations, which indicates their ‘substantive hybridity’. Based on the interrelated nature of these findings, we argue that it is through a process of placial substantive hybridity that rural social enterprises foster social innovation in order to contribute to an integrated development of their localities. They harness and (re)valorise (untapped) local resources while complementing these with other resources from extra-local sources and accommodate and/or respond to structural-exogenous forces based on the needs of their local population in line with neo-endogenous rural development.

Social innovation (SI) research tends to understand rural SI processes as collective initiatives of equally engaged, supportive, and like-minded people. However, recent research has indicated that SI projects often benefit from dedicated key players who find support in their communities but also must deal with resistance and barriers. Against this backdrop, this article explores the figure of the key player in SI research and exposes the patterns of rural SI processes with the empirical cases of two small communities in Germany that jointly created rural infrastructure systems, thus seeking emancipation from remote political and economic control and marginalization. Using the empirical cases, we tested and specified a heuristic framework of key players that combines analytical dimensions at the micro-, meso-, and macro-levels. According to our findings, the heuristic framework is appropriate for analyzing key players in rural SI processes. Notably, we show that SI processes benefit from assertive key players and strong communities capable of joint action. Both are crucial for dealing with internal opposition and overcoming external hurdles that appear when novel approaches irritate familiar solutions and routines.

The phenomenon of rural marginalisation has intensified across the European Union after the 2008 global economic crisis, since the traditional state forms have been proved unable to promote an all-inclusive governing. Beyond-the-state governance systems are socially innovative, horizontal, networked, and collaborative institutional arrangements that are committed to breaking through this rural marginalisation. Marginalised rural areas provide a favourable context for socially innovative governance, since they contain small cohesive communities, while at the same time poor governing penetrates them. Nevertheless, social innovation in rural governance remains largely unexplored. The novel contribution of this article consists in underlying this research gap and exploring the question of how socially innovative governance is fostered or impeded within marginalised rural regions. Comparative research was conducted in between the marginalised rural regions of Muhlviertel in Austria, Baixo Alentejo in Portugal, and Phthiotis in Greece. The comparative results revealed some of the parameters that foster socially innovative governance; a decentralized government structure, advanced interregional networking, a discourse dissemination among the stakeholders and the civil society, as well as an organizational stability of the involved institutions for social innovation to become embedded. This article points to socially innovative governance that has a more codified and systematized hypostasis by recommendation of unique governance qualities.

У статті наведено рівняння для дослідження залежності напруженості електричного поля в біологічно активних точках від параметрів радіоімпульсного випромінювання. Отримані результати дозволили провести аналіз якісних властивостей процесу взаємодії радіоімпульсного випромінювання з біологічно активними точками. Було запропоновано біологічно активні точки розглядати як діелектричний резонатор, поміщений в плоску діелектричне середовище. Тому, якщо частота заповнення радіоімпульсу близька до власної частоти такого резонатора, то можливо резонансне збільшення напруженості електричного поля в біологічно активних точках. При проведенні численних розрахунків було прийнято, що сумарний потенціал на мембрані біологічних клітин не повинен перевищувати величину в 100 мВ. У процесі теоретичного аналізу розробленої моделі було встановлено, що для підвищення життєздатності новонароджених телят хворих диспепсією їх біологічно активні точки слід опромінювати інформаційним радіоімпульсного випромінюванням в діапазоні змін параметрів: тривалість імпульсів 0,5 · 10-7 ... 1,5 · 10-7 с; період проходження імпульсів 0,5 · 10 .... 1,5 · 10-5 с; величина щільності потоку потужності 15 мкВт / см2; частота заповнення імпульсів 50ГГц; час експозиції 15 ... 20 с; напруженість електричного поля E0 = 8,8 В / м, Еср = 5,7 В / м.

Problem definition: Fulfillment flexibility, the ability of distribution centers (DCs) to fulfill demand originating from other DCs, can help e-retailers reduce lost sales and improve service quality. Because the cost of full flexibility is prohibitive, we seek to understand the value of partially flexible fulfillment networks under simple and effective fulfillment policies. Academic/practical relevance: We propose a general method for understanding the practical value of (partial) fulfillment flexibility using a data-driven model, theoretical analysis, and numerical simulations. Our method applies to settings with local fulfillment (i.e., order fulfillment from the originating DC) prioritization and possible customer abandonment, two features that are new to the fulfillment literature. We then apply this method for a large e-retailer. We also introduce a new class of spillover limit fulfillment policies with attractive theoretical and practical features. Methodology: Our analysis uses dynamic and stochastic optimization, applied probability, and numerical simulations. Results: We derive optimal fulfillment policies in stylized settings, as well as bounds on the performance under an optimal policy using theoretical analysis, to provide guidelines on which policies to test in numerical simulations. We then use simulations to estimate for our industrial partner that a proposed fulfillment network with additional flexibility equates to a profit improvement on the order of tens of millions of U.S. dollars. Managerial implications: We provide an approach for e-retailers to understand when fulfillment flexibility is most valuable. We find that fulfillment flexibility provides the most benefit for our collaborator when gross profits are high relative to fulfillment costs or centrally held inventory is low. Also, we identify the risks of myopic fulfillment with additional flexibility and demonstrate that an effective spillover limit policy mitigates these risks. History: This paper has been accepted as part of the 2019 Manufacturing & Service Operations Management Practice-Based Research Competition. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2021.0981 .

Mobile applications (hereafter, apps) collect a plethora of information regarding the user behavior and his device through third-party analytics libraries. However, the collection and usage of such data raised several privacy concerns, mainly because the end-user - i.e., the actual owner of the data - is out of the loop in this collection process. Also, the existing privacy-enhanced solutions that emerged in the last years follow an "all or nothing" approach, leaving the user the sole option to accept or completely deny the access to privacy-related data. This work has the two-fold objective of assessing the privacy implications on the usage of analytics libraries in mobile apps and proposing a data anonymization methodology that enables a trade-off between the utility and privacy of the collected data and gives the user complete control over the sharing process. To achieve that, we present an empirical privacy assessment on the analytics libraries contained in the 4500 most-used Android apps of the Google Play Store between November 2020 and January 2021. Then, we propose an empowered anonymization methodology, based on MobHide, that gives the end-user complete control over the collection and anonymization process. Finally, we empirically demonstrate the applicability and effectiveness of such anonymization methodology thanks to HideDroid, a fully-fledged anonymization app for the Android ecosystem.

In an effort for further improvement of LSCF hollow fiber membrane properties in oxygen purification application, this work studied the use of polyethylene glycol (PEG) with different molecular weight of 2000, 3400 and 6000 Da as a pore former. A well-prepared hollow fiber membrane was successfully fabricated via extrusion followed by a sintering method. The results showed that the addition of PEG increased the viscosity of the dope suspension and formed a constant asymmetric pore configuration of the membrane after sintering at 1250 °C. The increasing molecular weight of PEG also leads to a decrease in the mechanical strength of the membranes, indicating that finger-like pores were sacrificed by forming irregular pores. The gas tightness was also examined under room temperature which showed that membrane with PEG 3400 achieved the best tightness with the nitrogen permeability of 3.55 × 10−5 mol·m−2·s−1·Pa−1. The oxygen permeation of the membranes was also influenced by the addition of PEG, where the highest oxygen permeation flux of 6.07 × 10−8 mol·cm−2·s−1 was obtained using a hollow fiber membrane with PEG 3400 due to the existence of the lowest dense layer thickness.

Results of fourteen two-span continuous deep beams those made from ordinary reinforced concrete (ORC) as a reference and rubberized reinforced concrete (RRC) are presented and discussed in this research. The main parameters are the rubber ratios as a replacement with coarse and fine aggregate and shear span/depth ratio (a/h) is 1.33 and 1.66. Chip and crumb rubbers were used to replace coarse and fine aggregate respectively in four different amounts by volume (5%, 10%, 15%, and 20%). The proposed mix shows an ability to replace 20% of the aggregate (coarse or fine), and the production is still structural concrete. All beams design to fail in shear. The main crack is formatted between the intermediate support and the applied load diagonally. In spite of the inclusion of waste tire rubber in concrete has specific apparent degradations, the potential benefit seems to overlook the adverse effects and also provides the primary significant value of resolution for rubber waste problems. The results show that 20% volumetric substitution of natural coarse or fine aggregates with tier rubber reduced the ultimate load of continuous deep beams by 32.06% and 32.65% but significantly increases the ultimate deflection by 83.07% and 106.28% respectively. The ductility of rubberized continuous deep beams increases up to 36.95% when the replacement ratio of crumb rubber is 20%.

Amidst a world of never-ending waste production and waste disposal crises, scientists have been working their ways to come up with solutions to serve the earth better. Two such commonly found trashes deteriorating the environment are glass and tin can waste. This study aims to investigate the comparative suitability of response surface methodology (RSM) and artificial neural network (ANN) in predicting the mechanical strength of concrete prepared with fine glass aggregate (GFA) and condensed milk can (tin) fibers (CMCF). An experimental scheme has been designed in this study with two input variables as GFA and CMCF, and two output variables as compressive and splitting tensile strength. The results show that both variables influenced the compressive and splitting tensile strength of concrete at 7, 28, and 56 days (p

A novel Log periodic patch with circular slot antenna has been presented here, the perturbation of shape of antenna has been done by combining a triangular shape with a semicircular shape. The antenna proposed here is with a DGS structure on its ground plane and its effects on band width and gain enhancement of the antenna is analyzed. The substrate of FR-epoxy material with length, breadth and height 170 mm, 50 mm and 1.6 mm, respectively is taken for implementation of the antenna on it. This proposed antenna operates at 12 GHz to 18 GHz that includes Ku-band with return loss below-10 dB. The parameters of antenna like S-parameters, antenna gain, directivity, VSWR, surface current distribution and radiation efficiency are determined one by one to ascertain its better performance. The simulation as well as the measurement results are comparatively analyzed.

The compatibility problems become main concern in the utilization of biodiesel especially regarding to degradation and corrosion. The present study is conducted to describe the corrosion behaviour that occurs in steel tanks after contact with palm-based biodiesel for a period of 7 months. The storage tank used is respectively made of galvanised steel (GS), carbon steel (CS) and stainless steel (SS). It is performed in vertical cylinders with a floating-roof model. In every 30 days of storage time, the profile changes in the wall, roof and base surface of each tank were observed. The oil fuel properties were monitored in the parameter of viscosity, acid numbers, water content and oil colour. The topographic profiles on the surface of the walls and bottom of each tank wetted by biodiesel were examined over three zones inside the tanks using an endoscope imager. The main results of this study indicate that the tank steel with different protective layers exhibits different types of corrosion. The corrosion was localized in SS tanks but generalized in GS and CS tanks. The oil contamination in SS tanks was relatively lower than that in CS and GS tanks. The type of corrosion performed differently in different zones on the inside of the tank. The potential for leaks is greater at the base than on the walls and roof of the storage tank.

Monitoring the degradation of induction motors is an essential concern for industries, especially when there are high costs related to maintenance and their stops. Nowadays, there are many non-invasive ways to monitor the health status of induction motors, including sensors to measure temperature, magnetic field, vibration, current, and power. However, installing these sensors may not be a simple task since intrusive procedures such as engine disassembling, wire separation, and engine interruption are commonly observed. Thus, we propose MUCLA (Multiphase Clamp and Tracking - patent pending) as a new device and methodology for monitoring motor degradation by analyzing its stator current. MUCLA introduces a non-invasive current sensors array on a proposed clamp in the hardware perspective, while a spectral tracking methodology refers to our novelty in the software viewpoint. For end-users, the main MUCLA contribution relies on the combination of the simplicity of installation and the possibility of using the proposed device even when considering Variable-Frequency Drive powered engines. The results obtained with both simulation and practical tests show encouraging results over different input workloads and emulated degradation. Compared to the current initiatives, we can classify MUCLA as a better solution for industrial plants in terms of installation time, installation complexity, and cost.

The reliability of the result significantly affects the use of the Coefficient of Variation (within the test variation), which reflects the variability of the concrete properties rather than the standard deviation. For the estimation of reliability and precision, comprehensive statistical analysis (within test variation) is conducted on 534 test samples using a rebound hammer. Different standards, like BIS, EN, ACI, and ASTM, are used in this study to compare the test results. Empirical research revealed that there are contradictions in literature as well as the standards used in many countries. The present paper focuses on detailed investigations of uncertainty measurements of the surface hardness test by statistical parameters (range of rebound index, standard deviation, and Coefficient of Variation). The unbiased estimate of the variability parameters from the published results has been verified concerning to the European standard. Concrete parameters namely cement type, water to cement ratio, compaction deficiency, curing condition, and elevated temperature have an impact on the output of the rebound hardness in terms of the variability of the compressive strength. Based on the results, the authors are willing to propose amendments to the Indian code graciously in compliance with the variability of the rebound hammer.

Determining the properties of mine waste dump material is very difficult, it is caused by the difference of dimension between the laboratory equipment and field material size distribution. This study aims to determine the material properties from mine waste dump material using back analysis method after failure was occurred. The back analysis method is based on a trial and error concept which focuses on failure geometry and it is conducted by varying the cohesion and friction angle until the safety factor was less than 1.0. The laboratory results showed a 66.2 kPa change as well as a 48.8°friction angle deviation in mine waste dump material properties, while the back analysis indicated 33.7 kPa and 27.4°. It means, there is a reduction in the value. Therefore, the increasing in these properties are expected to allow the redesign of heap stability.

The restoration of contaminated sites is attracting increasing attention because of environmental considerations. Barrier walls using cement-based solidified soil are a popular and effective method for enclosing contaminated sites. However, the working environment of cement-based solidified soils is often complicated and results in concern about the durability of the walls. Hence, the deterioration behaviour of solidified soils under a working environment should be investigated. A type of marine soft clay deposited in the coastal Lianyungang region of east China was solidified by a cement–metakaolin composite; then, the specimens were cured under standard, saline solution and cycled freeze–thaw environments. When the specimens reached the designed curing periods, the unconfined compressive strength, mass loss, pH value and mesostructure were determined. The results show that (a) both saline soaking and cycled freeze–thaw environments unavoidably reduce the durability of cement-based solidified soils and (b) metakaolin incorporation can effectively resist the deterioration behaviour of solidified soils under such environments. In this case, the optimal incorporation ratio is approximately 3·0%, and (c) although strength enhancement by chloride (Cl−) ions was primarily inhibited by the water medium, metakaolin incorporation suppresses cracking on the surface and strengthens the integrity of the solidified soils.

Cooling enhances the energy conversion efficiency and output of photovoltaic (PV) panels. In this work, the effects of natural convection, forced convection, and evaporative cooling on the performance of polycrystalline PV panels were investigated. The output and efficiency of a cooled PV panel were monitored and compared to those of an uncooled PV panel under the same conditions. The cooling was conducted using an insulated channel installed below a PV panel. Natural convection cooling was investigated for various channel air gaps (H = 30, 60, 90, and 120 mm). Natural convection currents in the cooling channels were capable of cooling the panel with wide air gaps. In forced convection cooling, the air was introduced by fans installed at the bottom opening of the cooling channel with various air velocities (ua = 1, 2, and 3 m/s). Evaporative natural convection cooling was performed by a wetted fabric along the lower surface of the cooling channel, whereas evaporative forced convection cooling by pushing air along the wetted lower surface of the channel. The experimental data showed that the panel efficiency and output increased due to cooling. The experimental results of natural convection cooling revealed that the use of an air gap of 120 mm to cool the solar panel contributed to an increase in the panel daily energy production and efficiency by 1.7% and 1.2%, respectively. For forced convection cooling, using air at a speed of 3 m/s increased the daily energy production by 4.4% and the efficiency by 4%. Natural convection evaporative cooling increased the daily energy production and the efficiency by 3.6% and 2.7%, respectively. Forced convection evaporative cooling contributed, at a speed of 2 m/s, to an increase in the daily energy production by 3.8% and an increase in efficiency of 3.8%.

Energy management strategy is gaining much popularity due to the involvement of conventional/non-conventional power sources with an efficient energy storing solution to offer un-interruptible power demand. Thus, in this work a simpler logic control circuit based nonisolated bi-directional DC-DC converter with both battery and super capacitor topology is proposed. For the proposed topology, first its mathematical modelling in ideal-case with parasitic in every mode of actions is presented. To control the bidirectional DC-DC converter topology, its small signal model for individual buck and boost operation is obtained by using averaging and linearization technique. Then, a unified logic circuit-based controller is designed for the obtained systems to analyze the performance of the converter in the buck and boost mode operation. The performance of the proposed topology is verified through MATLAB/Simulink environment.

The disposal of metal plating sludge (PS) to landfills is an increasingly common practice in developed and developing countries. This paper presents a novel PS stabilisation technique using fly ash (FA)-based geopolymers as a waste management option. Strength and microstructural evaluations were carried out on PS-FA geopolymers at various values of factors, including liquid alkaline activator (L = sodium silicate (Na2SiO3)/sodium hydroxide (NaOH) ratio), L/FA ratios, FA/PS ratios and curing time. Increasing the amount of PS in PS-FA geopolymers reduced the total porosity, subsequently resulting in higher unconfined compressive strength (UCS) values. The main geopolymerisation product of the FA-based geopolymer was sodium aluminosilicate hydrate (N-A-S-H) gel. Since PS had a high calcium content, it would react with the high amount of silica and alumina present in FA to generate calcium aluminosilicate hydrate (C-A-S-H) gel in PS-FA geopolymers. This C-A-S-H gel coexisted with the N-A-S-H gel from FA-based geopolymers and hence significantly accelerated UCS development of PS-FA geopolymers over time. The UCS values of PS-FA geopolymers were found to meet the US Environmental Protection Agency requirement for disposal to landfills. The outcomes from this research can be translated into a regulatory framework for managing PS and diverting this industrial waste from landfills.

Superplasticiser (SP) is widely used in foam concrete industry to improve rheological properties since compaction and vibration adversely affect the stability of foam bubbles. This study aims to investigate the effect of polycarboxylate SP contents on the properties of foam concrete. Different water-cement ratios (w/c) were used, and the SP added to the mixture to adjust the spreadability. The density of 1500 kg/m3 was chosen for the production of foam concrete for semi-structural applications. Fresh, mechanical, transport and microstructure properties were analysed in this study. The results of this study showed that the content of w/c and SP had a significant impact on the performance of the foam concrete. Increasing the SP content enhanced the foam concrete’s mechanical and transport properties, but the best behaviour was through the use of 1.35% of SP. Smaller pore diameter, better pore distribution and higher portlandite peak intensity were achieved through the use of the SP. Overall, the superior behaviour of the foam concrete was achieved by the use of 1.35% polycarboxylate SP.

According to scientific studies dealing with the statistics of ICE (internal combustion engine) failures, most of them are registered in the ignition system (25%) and the power system (35%). The operable state of the ICE fuel system can be maintained by developing effective testing methods. For the purpose of theoretical research, a DBD-4 testing device was designed in the methodological part of the research. The use of the developed methodologies and instrumentation allowed carrying out experimental studies to diagnose the operability of the fuel supply system. Analyzing the obtained experimental data, it can be affirmed that: there is a stable relationship between the change in the ICE crankshaft speed and the change in the injection duration of the electromagnetic injector; the degree of wear of the electric fuel pump (EFP) is determined by the shift of the stable value of the crankshaft speed to the zone of low speed values at the same injection durations. The data obtained after testing the EFP allows planning a further algorithm of actions to maintain the operability of the fuel supply system.

This paper describes a statistical and mathematical approach to optimize the mechanical properties of a wood plastic composite with Polyethylene Terephthalate (PET) as polymeric matrix. Wood plastic composite are materials that consist of a primary continuous polymer phase, where a secondary filler dispersed phase is embedded, the filler generally is wood fibers or sawdust. The slack variable approach in mixture experiments, consist in selecting a component of the mixture as slack variable, to subsequently design and analyze the experiment in terms of the remaining components. With the experimental design information three slack variable model were fit. Using response surface graphs, we show how different compositions modify the mechanical properties of wood plastic composite. Besides, by the desirability function, the optimal formulation of the compound that simultaneously maximizing the mechanical properties of wood plastic composite, was obtained. Finally, the components proportions that provides the best tensile, flexural and compression strength are presented.

This paper explores the potential of water jet eductor to replace large condensers and vacuum pump in the thermal desalination systems, with heat source temperatures below 95 °C. The operational limit of eductor has been investigated for active vapor transport and condensation to produce permeate. Combined system and its operational principle have been proposed with critical examination based on suction performance of Eductor. Experimental and computational study are the primary methodology of this work. The computational analysis of single-phase flow in Eductor, is in proper agreement with the experimental data. The result showed primary pressure & area ratio has positive impact and swirl ratio has negative impact on suction. The extended thermal analysis summarizes strength of Eductor while working with lower temperature sources and optimum cooling capacity of proposed system. Considering the simplicity and reduction in footprint, proposed application has been highlighted. The research disseminates knowledge on maximum vacuum generation capacity of Eductor and operational limit of thermal desalination system.

Waste management has become a new challenge for the construction industries since rapid urbanization is taking place worldwide. Ceramic waste is one such material which is being originated from construction sites and industries, imposing a significant risk to the environment due to its non-biodegradable nature. With the goal of waste utilization, this study aims to predict the compressive and splitting tensile strength of concrete made with waste Coarse Ceramic aggregate (CCA) and Nylon Fiber (NF) by using two distinct machine learning algorithms, namely, Support Vector Machine (SVM) and Gradient Boosting Machine (GBM). A comprehensive data set for testing and training the models containing 162 records of compressive and splitting tensile strength test results were considered from nine mix proportions. For training the dataset, parameters like cement content, sand content, stone content, ceramic content, nylon fiber content, curing duration, and concrete strength were taken as input variables. The predicted strengths obtained from the SVM and GBM based models are found to be in close agreement with the experimental results. In terms of coefficient of determination (R2), GBM showed significantly better result for both compressive strength (e.g., SVM Overall R2 = 0.879 & GBM Overall R2 = 0.981) and tensile strength (e.g., SVM Overall R2 = 0.706 & GBM Overall R2 = 0.923) prediction. Furthermore, based on the statistical accuracy measures like the mean absolute error (MAE), mean square error (MSE), root mean square error (RMSE), it has been observed that GBM has yielded much better performance compared to SVM in predicting the mechanical strength of concrete.

This paper furthers and updates the research on the nature of the so-called global trade slowdown. Not only do we explain and discuss the determinants of this phenomenon, but we also offer an empirical description of the recent evolution of trade and trade elasticity. With the purpose of testing whether this is a structural phenomenon or not, we build an Error Correction Model for both world and regional data on trade and income using data from the World Bank for the period 1970-2017. World, OECD and Asian countries trade elasticity figures show a remarkable reduction after the hyperglobalization period (1986-2001), opposed to those of Latin America where trade volume has not stagnated so much. This slowdown might have major consequences for any country, but especially for those which have relied more intensively on trade as an engine for growth.Keywords: Global trade, Trade-income elasticity, ECM. JEL: C22, F15.

One-level optimization methods have been proposed to optimize a single user’s load profile or a cluster of users in the smart grids. In this work, two two-level optimization methods are studied, one case considering technical requirements (case 1) and another considering economic criterion (case 2). In the upper level, the supplier optimizes the objective function. Meanwhile, at the lower level, users optimize their electrical costs. The proposed methods are based on Genetic Algorithm methods. In this sense, an indirect control is established in which users react to a price signal. Simulation results illustrate that both cases improve the demand profile and increase the retailer profit concerning an unscheduled case. However, when the supplier tries to maximize the profit, some users receive benefits to detriment of others, concluding that the technical approach is preferable to the economic one.

A case study of the steel–concrete composite structure in the Pidie Jaya Regency Multipurpose Hall which experienced substantial permanent lateral deformation due to the effect of an earthquake is presented in this study. Therefore, it is important to assess the response of the structure to earthquake load and propose the strengthening strategies to make the buildings useful again. The purpose was to evaluate the causes of large deformations and the behavior of structure in resisting earthquake loads. The building structure model used in this study is a space frame with two-column base support conditions which are fixed and hinged supports after which a non-linear time history analysis was conducted. The time history analysis was conducted using five ground motion acceleration data recorded during earthquakes to determine the deformation and it was found that the large structure permanent deformation was due to the small structure stiffness in the direction of the deformation due to the use of only one column row in front of the building. Moreover, hinged support was observed to have caused a greater deformation than fixed support but was found not to be the main cause of large permanent deformation of the structure. The building structure was further strengthened by adding 4 columns while the oblique columns remained in a sloping condition. Meanwhile, the response spectrum analysis showed the strengthening structure was able to withstand earthquake loads with less deformation than the required standard.

Post COVID-19 vaccine development, nations are now getting ready to face another challenge: how to effectively distribute vaccines amongst the masses to quickly achieve herd immunity against the infection. According to some experts, herd immunity for COVID-19 can be achieved by inoculating 67% of the population. India may find it difficult to achieve this service level target, owing to several infrastructural deficiencies in its vaccine supply chain. Effect of these deficiencies is to cause frequent lead time disruptions. In this context, we develop a novel modelling approach to identify few nodes, which require additional inventory allocations (strategic inventory reserves) to ensure minimum service level (67%) under the possibility of lead time disruptions. Later, through an illustrative case study on distribution of Japanese Encephalitis vaccine, we identify conditions under which strategic inventory reserve policy cannot be practically implemented to meet service level targets. Nodes fulfilling these conditions are termed as critical nodes and must be overhauled structurally to make the implementation of strategic inventory policy practically viable again. Structural overhauling may entail installation of better cold storage facilities, purchasing more quality transport vans, improving reliability of transport network, and skills of cold storage manager by training. Ideally, conditions for identifying critical nodes for COVID-19 vaccine distribution must be derived separately by substituting COVID-19 specific parametric values in our model. In the absence of the required data for COVID-19 scenario, JE specific criteria can be used heuristically to identify critical nodes and structurally overhaul them later for efficiently achieving service level targets.

Branding Wooden Multi-storey Construction – Real-Estate Agents as Gatekeepers for Enhancing Consumer Value in Housing

Multiparty computation (MPC) consists in several parties engaging in joint computation in such a way that each party's input and output remain private to that party. Whereas MPC protocols for specific computations have existed since the 1980s, only recently general-purpose compilers have been developed to allow MPC on arbitrary functions. Yet, using today's MPC compilers requires substantial programming effort and skill on the user's side, among other things because nearly all compilers translate the code of the computation into a Boolean or arithmetic circuit. In particular, the circuit representation requires unrolling loops and recursive calls, which forces programmers to (often manually) define loop bounds and hardly use recursion. We present an approach allowing MPC on an arbitrary computation expressed as ordinary code with all functionalities that does not need to be translated into a circuit. Our notion of input and output privacy is predicated on unlinkability. Our method leverages co-utile computation outsourcing using anonymous channels via decentralized reputation, makes a minimalistic use of cryptography and does not require participants to be honest-but-curious: it works as long as participants are rational (self-interested), which may include rationally malicious peers (who become attackers if this is advantageous to them). We present example applications, including e-voting. Our empirical work shows that reputation captures well the behavior of peers and ensures that parties with high reputation obtain correct results., Comment: IEEE Transactions on Dependable and Secure Computing, to appear

A cost-effective stereolithography for medium-scale components is developed to fabricate 3D components with high build speed and resolution from photo-curable resin. The developed SLA utilizes a focused light beam of wavelength range (300 nm–700 nm) coming from the DLP projector and passes through the objective lens and finally imposed on the platform containing a layer of photo-curable resin. After focusing the light beam on the liquid resin layer, the photo-polymerization reaction occurs and the liquid resin becomes solid. Thus, the 3D object is fabricated layer by layer curing of liquid resin. The photopolymer used in this experimentation is polyethylene glycol di-acrylate and Irgacure 784 as photo-initiator. The Creo 3.0 software is used for modelling of 3D objects. A special MATLAB code is developed for slicing of the 3D model and displaying the sliced image one by one through DLP projector. The Arduino microcontroller with stepper motor and ball screw is used to control the motion of Z-stage platform. The Creation workshop software is also used to control motion of the Z-stage and period to display the sliced images through DLP projector. The medium-scale 3D objects with rectangular, square, and circular cross-sections are obtained by curing the aforementioned photo-curable resin. It is observed that the 3D objects are best cured for two seconds curing time with 0.1 mm curing depth along Z-axis.

Agriculture waste such as sugarcane bagasse (SCB) is composed mostly of cellulose, a very versatile natural biopolymer with well-established applications in many industries. The purpose of this study was to use combination treatment methods which include alkaline treatment and mild acid hydrolysis assisted with ultrasonication to extract cellulose nanofibers (CNFs) from sugarcane bagasse. Initially, the SCB fibers were treated with sodium hydroxide and aqueous hydrogen peroxide, a bleaching agent before subjected to mild acid hydrolysis followed by ultrasonication at 70% amplitude to defibrillate and disperse the fibers. The study focused on acid hydrolysis using mild sulfuric acid to the alkaline treated cellulose fibers extracted from SCB. The FESEM images of isolated CNFs exhibited diameter in the range 20–30 nm and length of up to several micrometers. This observation suggests that the combined treatment methods are highly effective in isolating CNFs from the plant biomass. Moreover, XRD analysis reveals the presence of peaks at 2θ of 15.2° and 22°, indicating cellulose type I with the crystallinity of 42%. Meanwhile, the FTIR spectra prove that individual CNF was successfully isolated due to the removal of non-cellulosic constituents. This result verifies that amorphous portions such as lignin and hemicellulose were completely removed. CNFs with long entangled network fibrils were successfully extracted from SCB through the combination of alkaline treatment and mild acid hydrolysis assisted with ultrasonication. The CNFs are expected to have high strength and aspect ratio that can be used as reinforced material in manufacturing nanocomposites.

This paper presents a practical optimum design solution of prismatic simply supported prestressed concrete girders that are subjected to uniformly distributed static loads. While assuming linear elastic behaviour and employing working stresses method, the optimum values of two design variables, namely the cross-sectional dimensions and the prestressing force, are formulated as a nonlinear optimization model. Optimum values of the design variables are computed to satisfy either a minimum weight or a minimum cost objective function. To solve the nonlinear programming models, a program named Non-Linear Programming Prestressed Concrete Optimizer (NLPRECO) was coded in MATLAB® programming environment. Some illustrative design problems were solved using NLPRECO and their results are demonstrated herein. Sensitivity analysis of the optimized design variables, to variations in design parameters, was also investigated and the results are presented. Results show substantial improvement over the regular un-optimized solutions and moderate improvement over a linear programming optimization solutions.

Nanoindentation derived mechanical properties and strain rate sensitivity assessment of a set of stir cast metallic reinforced Aluminium-based composites, with an antecedence of anomalous stress oscillations and strain rate insensitivity during hot compression, was investigated in this study. For the evaluation, Al6063 based composites reinforced with 6 wt% CuZnAl, steel, nickel, and SiC particles were subjected to nanoindentation, and their strain rate sensitivity was assessed using strain rate jump test. The results show that the AMCs reinforced with the metallic particles, presented better mechanical properties than those reinforced with SiC. The CuZnAl reinforced AMC had the best hardness (1.25 ± 0.25 GPa) and elastic modulus (∼83GPa), which is opined to be on account of thermoelastic contributions to the basic strengthening mechanisms. The large scatter observed in the mechanical response of the AMCs is largely due to the inhomogeneous particle distribution. The higher indentation resistance with an increase in strain rate, coupled with the absence of displacement bursts, indicated that the composites largely exhibit positive strain rate sensitivity.

The job sequencing and tool switching (SSP) is a well-known combinatorial optimization problem that aims to minimize the number of tool switches. The problem mainly arises in a flexible manufacturing system, in which machines can be configured with various tools to process different jobs and tool switches will correspond to a reduction of productivity. While the general studies assume uniform setup time for tool switching, applications on the industries indicate that the setup time of a tool might depend on the previously installed tool of the same slot. Therefore, this article proposes two integer linear programming models for the sequence-dependent SSP, namely the five-index formulation and the multicommodity flow formulation. Experimental tests are executed to compare the sequence-dependent SSP with the uniform SSP and the results show the effectiveness of multicommodity flow formulation. Finally, several managerial discussions are derived from the results.

This study addresses performances and behaviors of the multi-cross-section HAWT blade design with and without fences. The FX66-S-196 V, FX63-137 S and SG6043, supercritical airfoils were used and distributed along the blade radius; further, the NACA4412 single-cross-section HAWT blade having the same dimensions was used to compare the behaviors and overall performances of all the blades. Analyses were then performed numerically using blade elements momentum BEM theory with a self-code (F.90) and CFD as well as experimentally with three multi-cross-section blades designed using SOLIDWORKS and 3D- printed with polylactic acid. the multi-cross-section HAWT blades show good performance compared with the single- cross-section blade, with an approximately 8% increase in power coefficient, i.e., 40 W, for a miniature wind turbine (127 cm diameter 500 W output power) and greater improvements for wind turbines with large diameters. The fences were designed using boundary layer theory and installed on multi-cross-section blades in experimentally determined positions. The fences showed high performance, with a 16% increase in total power coefficient and high flutter stability.

In dieser Studie analysieren wir das Potenzial organisierter Interessen als Transmissionsriemen zwischen der Bevölkerung und politischen Institutionen im parlamentarischen System der Bundesrepublik zu fungieren. Wir verwenden Daten aus Experteninterviews mit Lobbyistinnen und Lobbyisten und einer repräsentativen Bevölkerungsumfrage, um die Kongruenz zwischen den Themenfeldern zu ermitteln, welche die Bürgerinnen und Bürger und organisierten Interessen in Deutschland jeweils als wichtig ansehen. Ferner analysieren wir, ob sich die Kongruenz hinsichtlich der öffentlichen Salienz des Themas sowie des soziökonomischen Status oder der politischen Einstellungen der Bürgerinnen und Bürger unterscheidet. Dabei differenzieren wir zwischen Unternehmer- und Nichtunternehmerinteressen. Die Ergebnisse deuten auf eine moderate Themenkongruenz zwischen den Agenden der Bürgerinnen und Bürger und der organisierten Interessen hin. Diese Repräsentationsleistung wird jedoch überwiegend von Nichtunternehmerorganisationen erfüllt, die verstärkt an Themen arbeiten, die für die Bevölkerung salient sind. Ferner sind Bürgerinnen und Bürger mit extremeren Einstellungen besser repräsentiert als jene, die sich in der ideologischen Mitte befinden. Hingegen zeigen sich keine Unterschiede hinsichtlich des Einkommens und Geschlechts oder zwischen Ost- und Westdeutschland., Projekt DEAL

Peak power demand strains electrical grids and increases cost of electricity generation, transmission and distribution infrastructure. Many studies have examined ways of reducing this peak power demand, including modification of room air temperature setpoints or the reduction of lighting levels. However, very few or no studies have examined the peak power reduction resource offered by temporary curtailment of building ventilation systems. For this reason, we conducted a simulation campaign in which we examined the resource offered by temporary ventilation curtailment in commercial buildings of different use types across the United States and in residences in the state of California, with the essential constraint that any changes resulted in air quality acceptable to occupants through additional ventilation to compensate for the curtailment. To do this, we employed previously validated building models implemented in the airflow and contaminant transport tool CONTAM and building thermal and systems modeling tool EnergyPlus, in some cases co-simulated. Results show savings are highly dependent on building type and climate but range from 0-2 W/ft2 and up to 40% of total peak building power demand. Depending on building type, this power shed can be conducted for 1.5-8 hours before acute exposure or odor concerns are expected, assuming a safety factor of 2. This reduction is of the same magnitude as that offered by thermal control strategies such as setpoint increase, or from lighting reduction strategies.

This paper presents the results of cement-based mortars characterizations that were taken from rendered layers of military bunkers in the Rupnik Line. The Rupnik Line was conceived as a part of the fortified defence system protecting the Rapallo Border between the Kingdom of Italy and the Kingdom of Yugoslavia, established in 1920. The bunkers were built between 1938 and 1941, and the renders of various compositions were applied as a camouflage layer that merged the bunkers with the environment. Results of petrographic examination and microstructural and chemical analysis of the samples confirmed that locally available crushed dolomite or limestone sands were used as an aggregate in the mortars. As binders, pure Portland cement or a mixture of cement and ground granulated blast furnace slag were used. The selection of the aggregate and binder type in a particular mortar was based on the colour of the artificial stone produced. All samples with the dolomite aggregate show the presence of alkali-aggregate reactions, dedolomitization of the grains and secondary calcite formation in the cement binder, along with the Mg-Al, Mg-Si and Mg-Al-Si phase formations. In mortar compositions with a high Portland cement content, the presence of delayed ettringite formation was also confirmed.

For each of (i) arbitrary stochastic reset, (ii) deterministic reset with arbitrary period, (iii) reset at arbitrary constant rate, and then in the sense of either (a) first-order stochastic dominance or (b) expectation (i.e. for each of the six possible combinations of the preceding), those laws of random times are precisely characterized that are rendered no bigger [rendered no smaller; left invariant] by all possible restart laws (within the classes (i), (ii), (iii), as the case may be). Partial results in the same vein for reset with branching are obtained. In particular it is found that deterministic and arbitrary stochastic restart lead to the same characterizations, but this equivalence fails to persist for exponential (constant-rate) reset.

We show that a A-linear map of Hilbert A-modules is induced by a unitary Hilbert module operator if and only if it extends to an ordinary unitary on appropriately defined enveloping Hilbert spaces. Applications to the theory of multiplicative unitaries let us to compute the equivalence classes of Hilbert modules over a class of C*-algebraic quantum groups. We, thus, develop a theory that, for example, could be used to show non-existence of certain co-actions. In particular, we show that the Cuntz semigroup functor takes a co-action to a multiplicative action.

Marine litter is one of the main sources of anthropogenic pollution in the marine ecosystem, with plastic representing a global threat. This paper aims to assess the spatial distribution of plastic macro-litter on the seafloor, identifying accumulation hotspots at a northern Mediterranean scale. Density indices (items km–2) from the MEDITS trawl surveys (years 2013-2015) were modelled by generalized additive models using a Delta-type approach and several covariates: latitude, longitude, depth, seafloor slope, surface oceanographic currents and distances from main ports. To set thresholds for the identification of accumulation areas, the percentiles (85th, 90th and 95th) of the plastic spatial density distribution were computed on the raster data. In the northern Mediterranean marine macro-litter was widespread (90.13% of the 1279 surveyed stations), with plastic by far the most recurrent category. The prediction map of the plastic density highlighted accumulation areas (85th, 90th and 95th percentiles of the distribution, respectively, corresponding to 147, 196 and 316 items km–2) in the Gulf of Lions, eastern Corsica, the eastern Adriatic Sea, the Argo-Saronic region and waters around southern Cyprus. Maximum densities were predicted in correspondence to the shallower depths and in proximity to populated areas (distance from the ports). Surface currents and local water circulation with cyclonic and anticyclonic eddies were identified as drivers likely facilitating the sinking to the bottoms of floating debris, Sí

In the National Development Plan, cooperatives and agriculture development are identified as possible solutions for addressing rural poverty and unemployment, especially among the youth. However, according to most research/literature, agricultural cooperatives fail for many reasons, including but not limited to lack of capital, incompetent management and organizational deficiencies. This study applied a qualitative analysis to the qualitative data using a case study of Zanokhanyo Food Security Cooperative (ZFSC) in Ndabakazi, Butterworth. Interviews with the project members, ex-members, extension officers and youth were conducted through a semi-structured questionnaire administered in IsiXhosa. According to the results, lack of intensive production resulting in very low incomes is one of the reasons why projects such as ZFSC fail to attract young people and provide employment for rural people. Agricultural extension advisory services play a very limited role because of their generalist approach; they lack depth of knowledge about diverse agricultural subject areas. This study recommends that agricultural extension and the farmers’ support system be improved by employing or outsourcing specialists to cater to the needs of agricultural cooperatives in order to improve the productivity and income of agricultural cooperatives.

Given a set $P$ of $n$ points in $\mathbb{R}^2$ and an input line $\gamma$ in $\mathbb{R}^2$, we present an algorithm that runs in optimal $\Theta(n\log n)$ time and $\Theta(n)$ space to solve a restricted version of the $1$-Steiner tree problem. Our algorithm returns a minimum-weight tree interconnecting $P$ using at most one Steiner point $s \in \gamma$, where edges are weighted by the Euclidean distance between their endpoints. We then extend the result to $j$ input lines. Following this, we show how the algorithm of Brazil et al. ("Generalised k-Steiner Tree Problems in Normed Planes", arXiv:1111.1464) that solves the $k$-Steiner tree problem in $\mathbb{R}^2$ in $O(n^{2k})$ time can be adapted to our setting. For $k>1$, restricting the (at most) $k$ Steiner points to lie on an input line, the runtime becomes $O(n^{k})$. Next we show how the results of Brazil et al. ("Generalised k-Steiner Tree Problems in Normed Planes", arXiv:1111.1464) allow us to maintain the same time and space bounds while extending to some non-Euclidean norms and different tree cost functions. Lastly, we extend the result to $j$ input curves., Comment: 31 pages (26 of content), 4 figures (last one as 3 subfigures). Minor corrections since publication: notably our analysis of the Brazil et al. k-steiner tree algorithm in section 4.1 (results unchanged), and a correction to some corollary statements to correct the space usage. Also added short discussion of how the algorithm still works when the MST of the input point set is not unique

Poisson Voronoi (PV) tessellations as artificial microstructures are widely used in investigations of material deformation behaviors. However, a PV structure usually describes a relative homogeneous field. This work presents a simple numerical method for generating 2D/3D artificial microstructures based on hierarchical PV tessellations. If grains/particles of a phase cover a large size span, the concept of “artificial phases” can be used to create a more realistic size distribution. From case to case, detailed microstructural features cannot be directly achieved by commercial or free softwares, but they are necessary for a deep or thorough study of the material deformation behavior. PV tessellations created in our process can fulfill individual requirements from material designs. Another reason to use PV tessellations is due to the limited experimental data. Concerning the application of PV microstructures, four examples are given. The FE models and results will be presented in consecutive works, i.e. “part II: applications”., Deutsche Forschungsgemeinschaft, Projekt DEAL