bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Color Image Watermarking Algorithm Based on Quaternion Fourier Transform
Authors: Ma Yongqiang , Wang Shunli , Sun Wei , Bian Jing , Liu YinBo
Published: May 2020

This paper mainly proposes a color image digital watermarking algorithm based on quaternion Fourier transform (QFT). We can describe color image as a quaternion matrix, then we can use QFT to get its frequency domain information. By using Fourier transform, we can embed the watermarking information into the frequency domain information. By using inverse QFT, we can get a color image that contain watermarking information. All of the steps can be reversible, so the watermarking extraction process is opposite to the embedding process. The advantage of processing color image by quaternion theory is that three color channels of the image can be treated as a whole.
Measurement of vibrations generated by high speed railway traffic and evaluation according to international norms
Authors: Ates S , Celebi E , Kirtel O , Zulfikar A C , Goktepe F
Published: May 2020

High-speed trains are one of the most preferred ways of transportation. The fact that it is fast and safe, cost effective and not being effected by weather conditions provides many advantages for passengers but there are also many disadvantages for the buildings close to the train track and the people who reside in these buildings. In this study, a series of site tests were performed to obtain the acceleration recordings of the vibrations existing in free field of the soil and building foundation. The average shear wave velocity of soil was considered as 200m/s and the velocity of the high-speed train was taken as 250km/h. In this study, it is aimed to reveal the kinematic interaction between the free field motion and foundation vibration of the building while high-speed train passed. Furthermore, vibrations occurring under the current soil conditions of the study area were evaluated according to the key parameters defined in regulations of the Federal Transit Administration Report (FTA) and Human Exposure to Vibration in Buildings/Effects of Vibration on Structures (DIN 4150-2/3). It is seen that the compliance with the limit values specified in the regulations changes according to the purpose of use. The results showed that rigid foundations significantly modify the wave propagation and vibration level due to kinematic interaction effects.
Physico-mechanical characterization of high-volume fly ash cement paste composites
Authors: Aydın E
Published: May 2020

The current annual worldwide production of coal ash is estimated at one billion tons of which at least 70-75 % is fly ash. A huge amount of such wastes can seriously damage the environment and ecology of the planet. In this study, a high volume of fly ash was used to produce environmentally friendly building products. The composites were designed as pure cement, and as a result, no aggregates were used. Composites are classified as non-load- bearing elements in the construction sector. Physico-mechanical characterisation of laboratory- produced composites was evaluated based on dry density, water absorption, apparent specific gravity, porosity, and compressive and flexural strength tests. Based on the test results, fly ash can be used as an alternative binder for building products. Water absorption test results of composites produced by 40% fly ash showed satisfactory results. Dry density measurements proved the lightweight nature of the composites. Compressive and flexural strength test results were within the limit specified by the international authorities in the building sector. The composites comprising 60% fly ash attained 30 Mpa compressive strength at 28 days. The produced samples can be used effectively for various civil engineering works. The utilisation of fly ash in construction could reduce the carbon dioxide emission and produce a better sustainable solution.
Utilization of large amounts of industrial wastes to improve sustainability of the construction sector
Authors: Aydın E
Published: May 2020

The concept of “sustainability” in the construction sector has increasingly led to the manufacturing of thermal comfort products composed of natural or recycled materials. Several such products are readily available in the market while others are still in the early stages of production or under research. The assessment of the sustainability potential of building materials as well as of entire buildings or structures is a significantly complex issue as it involves the quantification of three interacting and interdependent parameters: the environmental impact, the technical performance, and the lifetime. From this it is decidedly apparent that simply protecting the environmental impact (e.g., during the construction process) will not benefit the environment as long as an equivalent technical performance and lifetime cannot be ensured. This situation can be analysed using the definition of the so-called “sustainability potential”. To this end, bottom ash and marble dust were used as a replacement for cement (up to 70%). In this study, technical performance of the laboratory-produced composites was evaluated using mechanical and durability tests. The sustainability potential of the composites was also analysed using the reduction in cost and the reduction in carbon dioxide emissions of the produced composites. The test results showed that the pure cement paste composites are adequate for targeting controlled low strength and non-load-bearing elements in civil engineering works. Durability performance also proved that the composites are moderately resistant to sulphates.
Performance indicators in the construction industry: a study with Portuguese companies
Authors: Barros A , Sousa S , Nunes E
Published: May 2020

This paper aims to study the use of performance indicators (PIs) by business managers in the civil construction sector in a region that encompasses eight districts located in the north of Portugal. Through the literature review, it was possible to gather a list of twenty potential PIs used in this sector. Subsequently, a questionnaire was applied to a sample of construction companies from this region. A statistical analysis of the data collected allowed to identify the twelve most used and most important PIs for the companies surveyed. The results indicate that the companies involved in this study mainly use the traditional financial measures, however, recognize that non-financial measures, namely the customer satisfaction index, employee satisfaction, internal customer satisfaction index, and the training of employees, are increasingly important for the success of companies. The study also analysis the criteria to select PIs, its main benefits, and difficulties faced by companies on their usage.
Use of Slab composite with galvanized steel deck in reinforced concrete frame
Authors: Eissa M , Celikag M
Published: May 2020

Slabs composite with galvanized steel deck and in-situ concrete are commonly used in steel framed structures. This approach proven to reduce structural weight and increase the efficiency of structural design. Furthermore, the steel deck acts as permanent formwork and also as positive reinforcement after concrete hardening. The study reported in this paper concentrates on the use of composite slab with galvanized steel deck in reinforced concrete (RC) framed buildings. This requires the assessment of the system under flexural loads and slip forces that develops between the RC beam and the composite slab in shear transferring zone. Four-point static and push-off tests were used to find the flexural capacity of system and the amount of slip between the beam and the slabs. Results of the numerous experimental tests and analytical studies demonstrate that the composite slab can be implemented in RC frames since both composite beam flanges and RC beam flanges conducted by the same beam stem manifested almost the same flexural behavior and had roughly similar load-carrying capacity in static test. Moreover, no slip was developed between the RC beam and the composite slab in all four test cases with different reinforcement set up. This can be considered as an important advantage of this system.
Oxidation of reactive black 5 solutions with sulfate radicals activated by iron
Authors: Gamadze N , Pirgalıoğlu S
Published: May 2020

Textile Effluents are problematic effluents which cannot be treated with conventional biochemical treatment methods. One of the most promising methods for treatment of non- biodegradable wastewaters is advanced oxidation. In this study, effect of sulfate radical based advanced oxidation methods were investigated for treatment of an azo dye; Reactive Black 5 (RB-5). Sulfate radicals were activated with the addition of Iron(II) and Iron (III) Sulfate to the reaction medium. Effect of pH and persulfate dosage on RB-5 removal were also investigated. It was observed that runs which were conducted with Iron (II) ions yielded better results both in terms of RB-5 removal and reaction rate. It was recorded that RB-5 removal and removal rate both improved with increased persulfate dosage while optimum initial pH was found to be unadjusted pH which was measured as 3. RB-5 removal over 99% was observed in the run conducted at pH 3 with a persulfate dosage of 4 mM and FeSO4 (Fe(II)) dosage of 1 mM.
Design and verification of properties of heavy-weight concrete for the production of weights
Authors: Hela R , Bodnarova L
Published: May 2020

The paper deals with the design of composition and verification of the properties of heavy-weight concrete for the production of weights. Heavy weights from fine-grained heavy-weight concrete can be used as a substitute for harmful lead weights (sinkers) for fishing purposes. Lead fishing weights contaminate water, posing a risk to aquatic animals and birds. The production of fishing sinkers from heavy-weight concrete seems to be a possible substitute. A significant reduction in the use of lead fishing sinkers in the European Union is currently under preparation. The formulas of heavy-weight concrete from fine aggregate (fractions max. 2mm) were designed and tested. The consistency of concrete was designed for casting. The optimum vibration frequency of concrete compaction was determined at 75 Hz, resulting in a smooth, colourable surface. The density of the dried concrete after 28 days was 4000 kg.m−3 using a magnetite aggregate with an apparent density of 5.07 Mg/m3.
Evaluation of carbonation depth evolution tendencies of reinforced concrete buildings located in coastal and inland areas of north cyprus
Authors: Al Haj Houseen Q , Akpınar P
Published: May 2020

Carbonation is a critical concrete durability problem that is known to have potential adverse effects both on the concrete cover and steel reinforcing bars. This study involves detailed experimental investigations on the carbonation progress status of 149 samples from 39 existing buildings in North Cyprus that are located in coastal and inland areas. It is known that the varying exposure conditions in coastal and inland areas are likely to affect the durability performance of concrete buildings in different manners. Concrete core samples that were originally extracted from structures for compressive strength determination, were later tested by using Phenolphthalein indicator in order to determine the extent of carbonation occurred throughout their service duration. Besides studying their current carbonation states, the expected carbonation depth at the end of a 50-years of service life, as well as time needed to carbonate 30 mm-depth concrete cover were also investigated by using the Fick’s law. Results showed that 41% of the inland samples have been exhibiting satisfactory carbonation resistance performance according to Eurocodes, where this rate was as high as 71% for the samples obtained from coastal areas of North Cyprus.
Two dimensional determination of peak acceleration distributions during earthquakes
Authors: İpek Y , Akgün M , Özdağ Ö C , Gönenç T , Pamuk E , Dindar H , Atalar C
Published: May 2020

In this study, the two dimensional peak acceleration values between the bedrock and the ground surface is examined by using the soil bedrock model formed for a profile in the Bomova Plain in the east of Izmir Bay. For this purpose, two dimensional soil bedrock model was created for profile using microgravity and Extended Spatial Autocorrelation (ESPAC) method results. The S-wave velocities obtained from the ESPAC method were used to determine the density for microgravity modelling. After the density determination process, microgravity data on the profile were obtained by forward Talwani modelling. The obtained model is divided with gridding the data at regular intervals. In the study area, a recorded earthquake data used for deconvolution by soil-bedrock model known strong ground motion station BYN, and then transfer to the interface of bedrock in addition to obtain required bedrock data. Then, the calculated site- specific bedrock earthquake data was transferred from the bedrock surface of the grid model to the soil surface and layer boundaries. By combining these peak acceleration values for the profile, the two dimensional peak acceleration distribution for the profile was calculated.
Building services in timber construction – Investigation on difficulties and reliefs during the installation procedures in multi-storey timber residential buildings
Authors: Koppelhuber D , Magg A
Published: May 2020

Multi-storey timber construction has undergone a strong positive development in Austria in recent years. However, while there are constant advancements in materials, construction technologies, production stages and assembly methods in timber construction itself, the design as well as the installation procedures of building services in multi-storey timber buildings lags far behind these technological progresses. The principles of planning and installation of building equipment are generally similar to those within solid mineral constructions that could be identified in the holistic research project TGA-Timber. A comprehensive investigation of the installation procedure on 3 multi-storey timber-construction projects has been carried on site and during prefabrication within the past 2 years in Austria at Graz University of Technology. The emphasis was set on the identification of disorders and delays caused by installation procedure of HVAC-building equipment in timber construction. The results of this research release the large potential of optimisation of piping runs as well as time- und cost savings within the installations process of building equipment as part of an overall economical optimisation. This publication is an excerpt of the results generated for these construction site analysis and deals in particular with difficulties and disturbances that have occurred.
Modular timber structures
Authors: Kuda D , Petříčková M
Published: May 2020

Related to sustainability movement and minimizing the carbon footprint, timber structures are becoming more attractive. Wood, as main structural material, offers many benefits relate mostly to economic and ecological aspects, compared to other materials as steel or concrete. On the other hand, physical characteristics of wood complicate the usage of a timber for high-rise or large-span structures. It brings a new challenge for architects and engineers to deliver feasible solution for usability of timber, despite its features. One of the possible solutions could be implementation of CLT (Cross-Laminate Timber) panels in structural systems developed earlier for buildings made of prefabricated concrete slabs. SOM in cooperation with Oregon State University are currently testing composite slabs made of CLT and thin concrete layer reinforcing the wood and protecting it from fire. Although the system solution looks promising, and could bring the result, slabs limit using of the space in layout. On the other hand, frame structures would be much more efficient. This article comes up with an idea of modular frame structure, which could help to solve the problem. The scheme is based on “gridshell” type systems, where rods form a more efficient shell for dealing with stress forces.
An evaluation of level of knowledge, behaviour and attitude towards environmental footprint in secondary school students in Libya
Authors: Laama I F G , Özdal D , Onay T
Published: May 2020

The indications of the impact of activities of people on environment are called footprints. Footprints are targeting various concerns related with environment and they quantify resource appropriation or waste generation, or both. Knowledge on protecting environment is one of the important factor that may affect environment adversely, because knowledge determines attitudes and behaviours of someone to environment. This study aimed to assess knowledge, attitudes and behaviours of Libyan secondary schools students towards environmental footprint. A quantitative research employing a questionnaire including questions on demographic characteristics of students and 35 questions on student’s knowledge, attitudes and behaviours of students towards environment was carried out. Data were collected from 400 students in the last quarter of 2018 in four secondary schools located in Tripoli. Data were analysed using Statistical Package for Social Sciences, SPSS vs. 21, employing both descriptive and inferential statistical techniques. Majority of students (91.8%) were observed as having high knowledge on environmental footprint. A higher proportion of students were having moderate levels of attitudes (76.0%) and behaviours (65.8%) towards environment. When the impact of demographic characteristics on level of knowledge, attitudes and behaviours was studied using t-test, it was found that students whose fathers were graduated from master or PhD had significantly greater knowledge level compared to others. It is important to implement programmes for improving knowledge of different parts of population by both empowering school curriculum and involving public and private sectors for involving in policies and programmes for both improving knowledge of different population groups and encouraging them to safe behaviours towards environment.
Service quality factors in the construction sector: A literature review
Authors: Landy M F B , Sousa S , Romero F
Published: May 2020

This paper consists of an exploratory literature review whose main research objectives were the identification of the service quality factors that are considered more important in the construction sector, the service quality models that are used to measure quality, and how are they related to success factors. The research methodology is documental and based on a review of articles obtained from six major scientific databases. The description of the main results follows. In all cases, the traditional models of service quality were used as guidelines to explain and adapt to specific contexts. The typical parameters used in these models are reliability, responsiveness, communication, credibility, assurance, empathy with the client and construction quality. In some cases, additional dimensions were added. Success factors seem to be intrinsically related to project management, communication skills, professional skills, quality of the final product, design, aesthetic and innovation, where the three latter ones represent parameters that have gained recently preponderance. A holistic, flexible and adaptable attitude seems to be relevant to face dynamic and turbulent conditions and changing customer’s requirements and expectations. Overall, the results indicate a generalised conservative approach which characterises this sector.
On the issue of calculating the force factors acting on the working bodies of a single rotor screw compressor
Authors: Pronin V , Zhignovskaia D , Minikaev A , Yerezhep D
Published: May 2020

The subject of research is a single rotor screw compressor. For the proper compressor design, the forces and moments must be calculated. The cutter’s teeth have a circular shape, therefore, the calculation is reduced to the determination of a torque. This power calculation is based on the law of pressure change in closed cavities of a single rotor screw compressor depending on the angle of a screw rotation and the law of change in the horizontal projection area of a cutter’s tooth meshed with a screw, depending on the angle of a cutter rotation. The term “flat closed figure” in our task means the horizontal projection of the disk cutter’s tooth part meshed with a screw, which takes the form of a triangle or trapezoid. The work shows a horizontal projection of the engagement rotor screw with a disk cutter. To determine the torque acting on the central screw, it is necessary to calculate the circumferential forces acting on the screw and the shoulders of the application forces. The calculation method described above allows one with a sufficient degree of accuracy to determine the forces and moments acting on the working bodies of a screw single-rotor compressor, and therefore, to calculate the deformation of the parts of a screw single-rotor compressor.
Study of convective heat transfer in small-diameter channels
Authors: Gerasyutenko V V , Sharkov A V , Korablev V A , Kayalajnen A V , Minkin D A
Published: May 2020

This paper investigates the convective heat transfer in a tube made of stainless steel 12X18H9T with outer diameter of 2 mm and inner diameter of 1.5 mm. For the research an experimental setup has been designed and assembled. The experimental setup consists of a fluid pumping system and flow-measuring device, working area, electrical power system and temperature measuring system. The experiment studies of heat transfer intensity in small diameter channels are performed. The study compares experimental data obtained with the theoretical ones. The paper presents the graphs of the Nusselt criterion dependence on the Reynolds criterion and the dependence of the convective heat transfer coefficient on the Reynolds criterion.
Choice and justification of the optimum cooling temperature for HTS cable
Authors: Glushaev A V , Sokolova E V , Kravchenko D V , Kirilov D N , Khrustovskaia D A , Ivanov L V
Published: May 2020

At the first stage of designing a high-temperature superconducting (HTS) cable and its cryogenic refrigeration system (CRS), it is necessary to choose the optimum cooling temperature. The operating temperature is selected not only according to the critical parameters of the HTS conductor, but also taking into account other design and operational characteristics - geometry, length, operating current and the need to have subcooled nitrogen to prevent the occurrence of steam inclusions. Normally the range of cooling temperatures is limited by the critical temperature of the HTS conductor (THTS≤ 104К) and the triple point temperature of nitrogen (TLN≥ 63.15K). The choice of a certain temperature value will enable us to approximately evaluate the parameters of the CRS and overall characteristics of the cable. The article presents an analysis of the dependence of the electric power magnitude consumed by the CRS on the choice of the cooling temperature value and cable geometry. The analysis may be useful for determining the characteristics of the HTS cable operating at different temperature levels.
The use of sprayed powders to create coatings in the welds of oilfield pipelines
Authors: Ermakov B S , Alkhimenko A A , Shaposhnikov N O , Ermakov S B , Shatsky T E , Igolkin A F
Published: May 2020

The most damaged elements of oil field pipelines are welded joints, the life of which often does not exceed one or two years. The problem of anticorrosive protection of internal surfaces of welded pipe joints has not been solved to date. In this paper, the possibility of applying powder protective stainless coatings to the inner edges of the pipe adjacent to the annular weld is considered. The research of corrosion resistance and mechanical properties of pipe welded joints is presented.
Study of the structural state of the metal welded joint 2.25Cr-1Mo-V steel depending on the parameters of post-weld heat treatment
Authors: Titova T I , Shulgan N A , Borovskoy A S
Published: May 2020

The results of studies of the structural state and properties of welded joints of steel 2.25Cr-1Mo-V after various modes of post-weld heat treatment are presented. The study of all zones of the welded joint using an optical microscope at magnifications up to 1000 times was conducted. It was established that the structure of the weld metal and HAZ of the welded joint 2.25Cr-1Mo-V steel in all thermal conditions is represented by bainite with different contents and distribution of the carbide phase. The level of hardness of the welded joint in Vickers units according to ASTM E92 is studied. The following critical values of the Larsen-Miller parameter were determined: for which the weld metal and HAZ ensure the absence of brittle structures with hardness higher than 350 HV10, exposed to hydrogen and the formation of cold cracks, at which the required level of hardness for trouble-free operation is not more than 248 HV10 and at which the coagulation of carbides is too intense and leads to a decrease strength properties.
The study of thermal processes of the skin of the object of the whole-body cryotherapy (WBC) using numerical analysis
Authors: Yerezhep D , Minikaev A , Zhignovskaia D , Pronin V , Yerezhep A
Published: May 2020

The work investigated the thermophysical processes occurring in the cryosauna during cryotherapeutic effects on the human body. Experimental studies in the field of the whole-body cryotherapy (WBC) are complex, since studies are necessary in such a wide range of environmental parameters as phase state, temperature, heat flux density, gas flow velocity in the cryosauna. One of the solutions to this problem is the development of computer models of the processes of heat transfer of a biological object in a cryosauna, allowing a wide range of studies to be carried out without human experiments. In this paper, we analyze a modification of the design of a cryochamber with a biological object. In this work, several types of computer models will be created, the models of which vary depending on the geometry of the wall of the cryosauna chamber from 90 to 85 degrees. The paper will show how much it is necessary to pay attention to the geometry of the cryosauna and work on the modification of the geometry. This work shows that when the geometry of the wall of the cryosauna was changed, it turned out that it smoothed the temperature distribution along the length of the object, which, in turn, will positively affect further research in this area. The results can be applied to optimize the supply of cryogenic gas in saunas, further geometry modernization, as well as to increase the efficiency and safety of the WBC process.
Study of steel hardness effect on the abrasive wear resistance
Authors: Berezin N M , Peregudov A A , Andreev A K , Igolkin A F , Vologjanina S A
Published: May 2020

In the course of developing the territories of the shelf of the Northern seas, the Far East and Siberia, the problem of cold-breaking materials was particularly acute. More than half of the territory of the Russian Federation is located North of the January isotherm, which has a temperature of - 20 °C. In such areas, the performance of equipment, especially in winter, falls sharply. Breakdowns of tractor and bulldozer parts in winter, compared to summer, occur more often up to 6 times, and excavator parts - up to 7 times. At the same time, it was revealed that the most dangerous period of starting machines after stops. To prevent major breakdowns at temperatures less than - 35 °C, excavators, drilling rigs, and construction vehicles are stopped. And this is despite the fact that in accordance with the operating regulations, they must be operated throughout the year. The performance of mining equipment is greatly affected by wear. Unsatisfactory resistance of cast parts at low temperatures leads to large downtime and large economic losses. The relationship between hardness and resistance to abrasive wear is considered. Abrasive with different particle sizes was used for the tests. It is shown that there is no linear relationship between hardness and resistance to abrasive wear, that in conditions of low abrasive rocks it is enough to have average hardness values of the order of 47-50 HRS, and when working in highly abrasive rocks it is necessary to strive to obtain high hardness values of about 50-55 HRS.
Study of the rheological characteristics of the potato-based fish and vegetable mixture melt in the pre-die zone of a single-screw extruder
Authors: Aksenova O I , Alexeev G V , Temershin D D
Published: May 2020

This paper presents study of the rheological characteristics of the melt of the fish and vegetable mixture biopolymer in the pre-die zone of a single-screw extruder. The analysis of the flow index, being less than one, and that of the flow curves of the fish and vegetable mixture biopolymer melt, intended for production of expanded potato snacks, showed that the melt in a certain range of deformation rates can be attributed to pseudoplastic fluids. The results of the study represent important data in the design of the extruders molding units, on which the stability of the finished products quality depends. The results of the study can be used for mathematical modelling of the flow of the biopolymer melt in the pre-die zone of the extruder and can serve as justification of the screw rotational speed range in order to obtain extrusion foodstuffs of stably high quality.
The ecotoxicological aspects of using the marine benthic invertebrates skeleton in the production of active calcium substances
Authors: Oripova A A , Ovsuk E A , Sergienko O I , Uliyanov N B , Oripov U
Published: May 2020

Marine benthic invertebrates are susceptible to the accumulation of heavy metals and other pollutants from the environment, leading to the impossibility of their use as raw materials in the food production and pharmaceutical industry. In this paper, the accumulation of heavy metals in the shells and needles of Strongylocentrotus sea urchins was studied to assess the safety of the use of this raw material in the production of active calcium substances for food and medical purposes with the use of voltammetry analysis and capillary electrophoresis. High levels of strontium accumulation in the studied samples were revealed, indicating the unfavorable situation of commercial waters with respect to the presence of mobile forms of strontium.
The prospects for the use of electrogasdynamic systems in dry ice-cold generators of refrigerated trucks
Authors: Babakin B S , Voronin M I , Suchkov A N , Babakin S B
Published: May 2020

Cold sources for cooling refrigerated vans are divided into temporary ones, ensuring the maintenance of the required temperature in the body without recharging the batteries for cold cooling for a limited period, and constant, ensuring the maintenance of the set temperature without periodically renewing the supply of cold. Temporary sources of cold include ice-salt mixture, dry ice, frozen eutectic solutions, installations with liquid nitrogen. A constant source of cold is engine cooling. Dry ice cooling is devoid of the main disadvantages of other methods. It has a relatively high refrigerating effect with a relatively small volume occupied by dry ice. Dry ice cooling can be carried out by contact and non-contact methods. In the contact method, the blocks of dry ice are not separated from the product, due to which carbon dioxide pairs wash the products. With the non-contact method, dry ice is loaded into hermetically sealed containers. The authors have proposed an environmentally friendly, reliable scheme of the process of cooling the body of a refrigerator with carbon dioxide using electrophysical methods. EGD devices with moving and stationary electrodes developed by the authors were used as pathogens for the circulation of the gas mixture in an isothermal body, which allowed to reduce the consumption of solid carbon dioxide.
On the issue of the usage of sealed containers for cooling the refrigerant in refrigerated trucks
Authors: Babakin B S , Suchkov A N , Voronin M I
Published: May 2020

The paper deals with the problem of using machine-free cooling in refrigerated trucks for intercity transportation in order to ensure environmental safety and to eliminate noise from a working refrigeration machine when unloading refrigerated products from refrigerated trucks to the distribution network. A machineless method for cooling the body of a refrigerator truck with cold accumulators without direct contact with a cooling medium due to the usage of frozen sealed containers is proposed. The accumulation of cold (AC) is carried out, as a rule, due to the heat of the phase transition at the melting point or crystallization of individual substances or there mixtures. The research of water-salt systems, which are widely used for temperature stabilization in refrigeration, for storage and transportation of medicines and food products, is presented. The results of the melting and freezing of three cold storage substances, which are H2O and water-salt solutions with NaCl concentrations of 8 and 13 % are presented. According to the results of studies, the usage of pressurized containers in refrigerated trucks with machine-free cooling is beneficial and opens up great opportunities for cooling the air in various destinations.
Influence of Concrete Strength on the Stress-Strain Behavior of Spirally Confined Recycled Aggregate Concrete
Authors: Munir Muhammad J , Kazmi Syed M S , Wu Yufei , Patnaikuni Indubushan
Published: May 2020

Costly and non-environment-friendly methods are used to improve the inferior behavior of recycled aggregate concrete (RAC). Conversely, the strength enrichment of concrete due to confinement provided by lateral reinforcement is ignored in the design of concrete compression members. The focus of this study is to investigate the role of pre-existing transverse reinforcement and different design strengths of concrete on the stress strain behavior of RAC. For this reason, stress-strain behavior of spiral steel confined concrete specimens having variable confinement pressure, recycled aggregates (RA) replacement percentage and design strength is investigated. The results show a drop in compressive strength of concrete with the increase in replacement percentage of RA. However, steel confinement has a positive role to counterbalance the adverse effect of RA replacement on concrete strength. Improved ductility and stress-strain behavior of RAC are observed with the increase in confinement pressure. Based on the results, the un-utilized pre-existing steel spiral reinforcement in the concrete compression members can offset the inferior performance of RAC resulting into sustainable and cost-effective construction.
Adaptability of Materials in Green Buildings: Australian Case Studies and Review
Authors: Gharehbaghi Koorosh , Rahmani Farshid , Paterno David
Published: May 2020

Globally, more and more buildings are constructed as the basis of green methodology. Green building methodology includes the reduction of energy from the conception through the operation phases. Importantly, the practice of green building is gradually becoming more regulatory compliance rather than optional. Subsequently, this paper will carefully review the adaptability of materials in green buildings. In supporting such aim, this paper will also reviewed five Australian case studies. For these building, as a part of adaptability of green materials, recycled concrete, metal and timber were utilized. It was found that most benefits of adaptability of materials for these buildings were significantly improved with the integration with sustainable design. Such alignment is the key for effective material selection and usage in green buildings. The use of green materials alone may be not be enough to considerably reduce the energy usage. Holistically, the green design together with recycled materials need to be combined to deliver efficient green buildings.
A Study on Properties of Concrete Made with Processed Granulated Blast Furnace Slag as Fine Aggregate
Authors: Vibha Venkataramu , Venkatarama Reddy B V
Published: May 2020

This study focusses on understanding the influence of processed granulated blast furnace (PGBS) slag on fresh and hardened state properties of concrete. Nowadays, metallurgical slags are being explored as alternative materials to natural virgin aggregates in concrete. Before using any such material in concrete, it is important to understand its influence on properties of concrete. In this study an attempt has been made to use granulated blast furnace slag from a local steel plant as a substitute to natural sand in normal concrete. The study mainly focusses on understanding the influence of different replacement ratios and suitability of slag replacement ratios higher than 50% in normal concrete. The blast furnace slag used in the present study was processed using a vertical shaft impactor to modify the particle shape and enhance its aggregate properties. The replacement was done at 50%, 75% and 100% by mass of natural sand in the concrete mix. The concrete properties such as slump, compressive strength, splitting tensile strength and flexural strength, were studied at all the replacement ratios.
Conceptual Residential Design Framework to enhance Well-being of Elderly in Thailand
Authors: Ruengtam Porntip
Published: May 2020

A conceptual residential design framework was modelled using healing environmental and universal design concepts to enhance the well-being of the elderly in Thailand. Research methods involved informal interviews and observations for three Thai case studies. Interview results were summarized with related theories and literature. All factors were collated and listed. Seven experts in related fields were employed to confirm the factors and framework following the Delphi technique. Results showed that elderly characteristics had a positive direct effect on requirements of the elderly in a residential community which comprised two sub-factors including (1) healing environment, and (2) universal design. Each factor affected the willingness of the elderly to join communal events of the residential community. This framework will be used for quantitative analysis to determine future policy for environmental design and management of residential communities to enhance the well-being of the elderly in Thailand.
Local Climate Zones Definition in Relation to ENVI-met in the City of Dubai, UAE.
Authors: Bande Lindita , Manandhar Prajowal , Marpu Prashanth , Battah Mohammad Al
Published: May 2020

The city of Dubai has experienced a rapid urban growth in the last 60 years. Located in the north west of the United Arab Emirates, Dubai has a linear development expanding mainly towards the coast. However recently this expansion is going towards the desert. Mapping such development creates a history that is relevant to many research entities. WUDAPT is a network that facilitates city mapping. With open source tools it is possible to create Local Climate Zones (LCZ). This zones have similar properties. Therefore, in the end of the process it would be possible to see the most dense urban areas of the city where the UHI phenomena is higher.

The process of mapping involves, Google Earth Pro, high definition satellite images and the CFD software, ENVI-met. The first two tools detect the LCZ and create the general map of the city. Then this map is compared with the validated models of ENVI-met. This comparison shows the connection of the UHI between one approach and the other. The site data taken from an open-source are used as a boundary condition in the simulations. The climate of Dubai is hot arid, with high temperatures in the summer and cool winters. The spring and autumn are short periods of 2-4 weeks.

The aim of this study is to detect problematic areas in the city in terms of surface/air temperature, high levels of UHI. This detection helps understanding where should be intervened in order to have more walkable districts.
Cyclic Tests of Joints of Glued Wooden Structures
Authors: Aruova L B , Ospanova Z N , Aruov B B , Alibekova N T , Shashpan Zh A , Kyrgizbaev A T
Published: May 2020

The use of large-span structures made of glued wood in countries with large timber reserves in Finland, Sweden, Norway, Russia, the USA and Canada has shown that this can be quite interesting and expressive from the architectural position of the building. Sports facilities, sports and sports facilities, sports facilities, sports and cultural facilities. The practice of building bridges made of glued wood in these countries shows that they have been in operation for decades without additional operating costs. Glued wood in modern conditions, when productive flame retardants are used that protect it from fire, antiseptics from possible decay expand the scope of such structures. One of the important obstacles to the limiting applications of large-span glued wooden structures is the complexity of the solution nodes. Bearing structures experience difficulties when exposed to static and cyclic loads. Cyclic loads can be caused by wind loads, production equipment, traffic, and seismic processes. Reinforcement in wood, reinforcement and reinforcement under load. Wood and metal are resistant to cyclic loads. Studies will be conducted at the border of the elements to be glued. This article presents the results of tests for the effects of static and cyclic loads on reinforcement from a 14 mm reinforcing bar of class A5 on FRF-50T along natural-sized glued wood fibers. Certain coefficients of the endurance of the compound when exposed to cyclic loads with two load asymmetry coefficients p = 0.5 and p = 0.2.
Performance of buildings around a long irregular excavation by top-down technique in downtown Nanjing
Authors: Gu Z X , Li H , Meng Z L , Lu H Z , Sun Y
Published: May 2020

A 1257 m-long irregular deep excavation was located in the city center of Nanjing, China. The full-width and half-width top-down construction method was adopted. The deformation characteristics of the settlement of adjacent buildings based on field data is discussed, and the interrelationships between building settlement and excavation process, structural system and geological conditions are also considered. The analysis results show that building settlement is related to the excavation deformation, construction sequence, structure forms, foundation types and the distance to the foundation pit. Corner effect has played an important role in building settlement and will affect the settlement pattern eventually. The settlement surface of building outside the pit corner is three-dimensional, while the building located in the middle of the long side of the pit has a two-dimensional settlement surface.
Determination of earth’s gravitational acceleration and moment of inertia of rigid body using physical pendulum experiments
Authors: Yuningsih N , Sardjito S , Dewi Y C
Published: May 2020

To determine the value of earth’s gravitational acceleration, physical pendulum experiment is preferred over simple pendulum experiment that was previously more popular. In physical pendulum experiment, the object is a rigid body. The swing period and swing shaft position are measured. From these two variables and using the applicable laws of motion, equations can be determined that involve constants which imply the value of the earth’s gravitational acceleration and the moment of inertia of objects pivoting at the center of mass. The independent variable in the equation is a function of the distance of the pendulum shaft to the center of mass based on the parallel-axis theorem, while the dependent variable is a swing period. Difficulty in solving equations is found because of the terms of the equation involving variables in different ranks. In order for the equation to be linear, a dependent variable and an independent variable are combined into new variables. After that, with the linear regression method, the constants of the equation can be determined which can then be determined the value of the earth’s gravitational acceleration and the moment of inertia of the object. The results obtained are quite satisfactory with a relatively smaller error value of 5%. Thus this physical pendulum experiment can be used to determine the earth’s gravitational acceleration and the moment of inertia of an object simultaneously.
Physicochemical characteristic of hydrogen-rich water potato flour
Authors: Budiarti G I , Sulistiawati E
Published: May 2020

Potato may be used as a substitute to wheat which cannot be grown in the tropics. However, potato flour has characteristic physicochemical limitation compared with wheat flour. Potato limitation can be reduced by modification starch. Hydrogen rich water is water that contains antioxidants. It has only been used in the health sector as an anticancer and anti-inflammatory. The antioxidant content in hydrogen rich water can be used for modification of potato starch which is safer than using chemicals. This study examined whether hydrogen-rich water can improve the physicochemical characteristic of potato flour as a substitute for wheat flour. We used a variation of soaking time in hydrogen-rich water (1,2,3,4 hours) and drying method (oven and UV). We found, physicochemical characteristic (water content, swelling power, and reducing sugars) better than wheat if soaked for 3 hours with UV drying method. So, modified potato flour using hydrogen-rich water can be considered as a substitute for wheat.
Effect of Absorbent for Gas Purification Unit in Biomass Gasification Process with Downdraft Method
Authors: Amelia Shinta , Maryudi  , Aktawan Agus , Astuti Erna
Published: May 2020

The development of industry causes energy needs to increase. So that fossil energy reserves are increasingly depleting. This resulted in the growth of various alternative energies. One alternative energy that is being developed is biomass-based energy. Biomass is a renewable energy source that comes from plants both directly and indirectly. Indonesia is a country with a tropical climate that has a very large biomass potential. One of the methods that can be used in processing biomass is gasification, which is a process to convert solid biomass raw materials into fuels (syngas). The problem from the gasification process is the syngas produced has a low purity level. This is because there are still impurities that are contained in syngas. Therefore, a purification unit is needed in the gasification device. This research aims to make absorbents that can be used in gasification purification units. The types of absorbent used is coconut shell activated carbon. The pore structure of carbon is characterized by using an N2-sorption analyzer (Nova 2000, Quantachrome). Based on the results of characterization, it can be seen that the specific surface area of activated carbon absorbent from the coconut shell is 1320 m2/gram with an average pore diameter of 1.82 nm. The experiment device mainly consisted of gasification reactor, filter, and blower. The gasification reactor was installed to heating the biomass with the supply oxygen. The reactor had a height of 170 cm and a diameter of 50 cm in which the bagasse with the capacity of 15 kg/h was quickly burned. The gas filter contains the absorbent to clean the syngas product. The absorbent was installed in upper four holes. The blower was used to suck up the syngas. Some thermocouple and gas indicator were installed to monitor the condition in the system. The syngas production was analyzed by the GC/MS analysis. The effect of absorbent is to improve the syngas composition such as CO, H2, and CH4. The syngas contents in our experiment were CO, CH4, and H2 with a percentage of 9.294%, 1.348%, and 7.773%, respectively. These results are better than the previous research with the syngas contents are 7.891% of CO, 0.100% of CH4, and 0.889% of H2 because the previous research was not equipped the absorbent.