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Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to their high heat transfer capabilities, energy absorption and sound insulation characteristics, lattice structures are used in different industries, especially in aviation, automotive and biomedical industries. Different process and geometric parameters are effective on these capabilities of lattice structures. It is well known that the use of suitable lattice structure together with appropriate process and geometric parameters in different industrial applications increases the efficiency obtained as a result of the application. This experimental study focuses on investigating the effect of lattice structure type, build direction and volume fraction on distortion, surface roughness and wall thickness deviation of lattice structures based on Taguchi design of experiment. Laser powder bed fusion process and CoCrMo material were used for production. The effect of each parameter on distortion, surface roughness and wall thickness deviation, and optimum parameter set were found by analysis of variance (ANOVA) method. The optimum parameter set for surface roughness was determined as diamond lattice structure, 0.2 volume fraction and 90o build orientation. On the other hand, the optimum parameter set for wall thickness deviation was determined as gyroid lattice structure, 0.4 volume fraction and 45o build orientation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Textiles & Engineers / Tekstil ve Mühendis is the property of Union of Chambers of Turkish Engineers & Architects, Chamber of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sound insulation is a kind of measure to prevent sound waves from penetrating through a material. Good sound absorbing materials are known to be lightweight, loose, and porous products. In this study, a new design approach is presented to improve the sound insulation properties of lightweight aggregate concrete blocks. Within the scope of the study, pumice, and volcanic tuff were used as lightweight aggregates in the production of concrete blocks. The acoustic properties of the masonry block specimens, in which alternative sound absorbing environments with special design are created, were analyzed on the model specimens. In particular, the effects of 3 different slit widths (12 mm, 16 mm, 20 mm wide) on the sound absorption performance of the masonry block element, in which the Helmholtz resonator form was created in its design, were investigated. The geometry of the lightweight concrete blocks is designed with three rows of gaps, and on the outer facing of the block, 4 sound slits were created at 80% of the block height to increase the sound absorption capacity, and the gaps on these sides are turned into open gaps. In addition, the technical findings of the design forms of polyester fiber felt used as reinforcement material to increase the sound absorption capacity of the block were also discussed comparatively. According to the study findings, it has been determined that as the slit width in the block design gets larger, the amount of sound received into the cavity volumes in the form of Helmholz resonator increases, and therefore it functions more as a sound absorber. In addition, with the polyethylene fiber felt reinforcement, an additional sound absorbing performance of 1.67 times is provided in the 16 mm slit block and 1.74 times in the 20 mm slit design block. [ABSTRACT FROM AUTHOR]

In architectural practice in Turkey, a high level overlap between the first design and the final product is not mostly seen. This may be resulted in poor performances (like aesthetical, functional) of buildings during the use phase. Also, buildings are influenced by such impacts as water, heat and sound in relation to their environmental conditions during their life cycle. Taking necessary measures against such impacts in the design phase is important for preventing problems that may arise during buildings usages. In addition to thermal insulation in Turkey, regulations on waterproofing and noise entered into force from the June 1, 2018. After this, water and sound insulation implementations in new buildings have become mandatory. This study, which is limited to the ‘Regulation on Waterproofing in Buildings’ and ‘Foundations’, includes a proposal using for the determination and control of the necessary waterproofing measures in the foundations of new buildings. It is envisaged that checklists can be used as a support tool for design and inspection in the period from design to usage. It is thought that the increase of similar list proposals for other building elements would be beneficial in reducing the breaks in the design and implementation phases of buildings. [ABSTRACT FROM AUTHOR]

Copyright of Online Journal of Art & Design is the property of Online Journal of Art & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sound insulation models that we use in this study are based on theoretical computations and their aim is to reduce time, labor and cost consumption during the calculation of "Sound Transmission Loss (R)" of a particular material experimentally. In this study, for 11 different materials, we compare the performance of various simulation models with the experimental results that are already available in the literature. The experiments were carried out with Bastian, Akuzoft, Insul and dBKAisla model. The analyses were conducted in the standards of ISO 12354, ISO 10140 and ISO 717 in 1/3 octave band. In the models, basic formulas from the literature, computation methods that is necessary to be used in R value calculation for single panels, dimensions of the panels, thickness, density, elasticity module, porosity, internal loss factor belonging to the material and velocity of sound in air have been taken into consideration. In summary, we conducted the simulations with different sound insulation models for the materials whose R values correspond to particular frequencies that have been calculated using experimental work. Comparing the results, effectiveness of each model has been calculated in terms of R and "Weighted Sound Reduction Index (Rw)". [ABSTRACT FROM AUTHOR]

Conservatory buildings, which have a special role among other educational buildings, should have appropriate acoustic conditions for an effective education and teaching. Based on this view, choosing Ankara Musiki Muallim Mektebi Mamak Municipality Conservatory Building as a sample, this study analyzed parameters such as speaking rate, background noise level, suitable spatial dimensions, sound insulation values that should be met in construction components, reverberation time and speech intelligibility. In this context, Insul 6.4 simulation program was used to determine sound transmission losses of construction elements of Ankara Musiki Muallim Mektebi Mamak Municipality Conservatory Building. Environmental noise level, background noise level and sound transmission loss of construction elements were measured. The results obtained were compared to the results of the simulation program; the results were evaluated and suggestions were made for inappropriate conditions. [ABSTRACT FROM AUTHOR]

Interior noise factor plays an important role in today's customer' preference for vehicle brands. All car manufacturers and suppliers develop their investment in this respect. Today's changing needs and the competition having taken place among car manufacturers cause the isolators to be constantly upgraded. It is possible to use various methods to determine the sound absorption coefficient of the isolators. In this study, five isolators that have the same thickness and different structural features and that are to be used in a specific location of the car were selected, and their sound absorption coefficient were measured using an "Impedance Tube". The results obtained were compared to each other, considering the structural features of the materials, and the changes they created in the internal noise were also analyzed. [ABSTRACT FROM AUTHOR]

Due to the rapid energy consumption, many studies have been done on alternative energy generation methods. In this sense, insulation has an important place from the point of energy saving. Energy loss can be minimized by insulation technologies. Insulating materials produced by favourable methods, can be healtier, more durable and economic. It is expected a huge increase on demands of insulation products because thermal and sound insulations are considered during construction. In this study, it is examined the usage of cotton waste, fly ash and epoxy resin on production of chipboards. Thermal conductivities, sound insulations and bending strengths of chipboards with different thickness were tested. Radioactive properties of samples containing barite were also investigated. All tests were performed by considering to Turkish Standarts. It was resulted that usage of cotton waste and fly ash had a positive effect on the engineering properties of chipboards. It was proved that ligth-weight construction materials produced with cotton waste, fly ash and epoxy resin could be used for getting better thermal and sound insulation results. Besides, radioactive permeability was measured lower on samples containing barite. [ABSTRACT FROM AUTHOR]