Octagonal Shape Research Articles

Optimization of Fuzzy Mathematical Model of Regular Octagon-Shaped Parking Space

In the vigorous development of the city population, there is a need to set up clear dimensions for the parking space. Car parking plays a significant part in the residential apartments and commercial buildings. Roadside parking spaces will create a huge traffic problem if the parking lots are not properly designed. Sometimes, it leads to the accident. Hence, keeping all these causes in mind, the flexible parking space is the necessary of the time. In the proposed research work, the parking space considered in the problem is of a regular octagon shape, and the mathematical model is developed under a fuzzy environment. LINGO Optimization Software is used to solve the mathematical model and MATLAB(Matrix Laboratory) is used to define the fuzzy variable. At the outset, the results will reveal the importance of making the length of the parking lot under fuzzy environment.

Aplikasi Material Rotan Pada Perancangan Table Lamp

Rattan is one of the main materials in simple crafts and a material for interior furniture items. In Indonesia, rattan is very abundant and is one of the largest rattan producing countries in the world. On the other hand, this rattan material is very popular with furniture entrepreneurs because rattan can be made into creative products that have features both in terms of function and aesthetics.. Furniture produced includes chairs, tables, and decorative products. The application of rattan in making table lamps is found on the hood which uses rattan material with a four-axis rattan weaving technique. This technique Arrange the woven material in 4 different directions and will produce a woven pattern with more holes with hexagonal and octagonal pattern shapes. On the lamp body is made of wood glued to the sides of the wood. So the process of making this table lamp is through material observation and experimentation. The purpose of this design is to increase consumer attractiveness to interior needs. The application of rattan material in the design of table lamps produces products that are not only aesthetically pleasing, but also pay attention to aspects of sustainability and functionality needs.

Full-field stress-strain analysis of octagonal shape PMMA using reflection photoelasticity

This research involves stress-strain analysis in poly(methyl methacrylate) (PMMA) octagonal shape compressed by hydraulic system. The observation of uniaxially stressed samples was carried out using reflection photoelasticity technique. The results of fringe order number and principal stress angle were used to determine stress and strain distribution in the samples by shear difference method. It was found that high stress-strain region was close to the contact point where compressive force was applied but it was zero at the edge of the samples. The area of high strain region increased as the magnitude of force was increased but it decreased as the dimension of octagonal shape was increased.

Aranyapur Pancharatna Temple: A Study of its Archaeological and Historical Significance in Cumilla, Bangladesh

Ratna style temple architecture flourished in the Bengal Delta from the mid-17th century to the 19th century. Although there is a clear distinction between the Ratna style temples and the ancient Bengal temples built in the North Indian Nagara and South Indian Dravidian styles, a careful analysis of the architectural structure of the Ratna temples reveals influences from both North and South Indian temple architecture. The incorporation of Indo-Islamic architectural features into Ratna temples, as seen in other contemporary structures like mosques, palaces, and forts, has given this style its uniqueness. This style of temple construction is not found elsewhere in the Indian subcontinent, except in the Bengal region. Among the various Ratna styles, the Pancharatna temple architecture is the most prevalent. The aim of this study is to review the origin and development of the Ratna style temple in Bengal and to provide a brief insight into the amalgamation of various architectural styles in the Pancharatna temples across Bengal by examining the architectural features of the Aranyapur Pancharatna temple in Cumilla. Through field surveys and photographic data analysis, the researcher has identified the architectural characteristics of the Ratna style, including Indo-Islamic and European influences, as well as the indigenous Chala style of Bengal. Additionally, other features of the aforementioned temple, such as its octagonal shape, sanctum sanctorum, arched circumambulatory path, three entrances on three sides, and the curved cornice of the central Ratna, have been compared with those of other Pancharatna temples in Bengal.

Application of the image‐well method for transient borehole thermal energy storage systems with complex boundaries

AbstractThis study introduces a new analytical framework that employs the image‐well method to simulate the spatial and temporal temperature distribution in vertical borehole thermal energy storage (BTES) systems. The model accommodates complex boundary shapes and conditions, including insulation, convection, and constant temperature, without requiring iterative solutions at each time step. The model's accuracy and utility are demonstrated through an application to a borehole heat exchanger cluster arranged in an octagonal shape with insulating boundaries, based on a BTES site in Drake Landing (Canada). Model predictions are validated against a finite element model, showing a root‐mean‐square error of 0.012°C. A global sensitivity analysis highlights the influence of thermal parameters on system performance, identifying the heat flux of the borehole heat exchanger as the most sensitive parameter. Overall, this approach combines the advantages of analytical and numerical techniques to provide a clear and efficient tool for evaluating BTES systems, offering significant potential for advancing sustainable energy solutions.

Wideband dual‐polarized rasorber design with genetic algorithm synthesis

AbstractIn this letter, an 11 GHz centered wideband absorptive frequency selective surface (FSS) design is presented. The absorptive FSS is dual polarized, and it has wide transmission band and a wide absorption band at the lower frequency side of the transmission band. An octagon shape with parallel microstrips toward center connected with lumped element resistors at the edges is proposed for the resistive layer unit element. Also, a multilayer octagon patch and aperture resonator are proposed for the wideband bandpass layer. As an alternative design method, the unit element of resistive layer of absorptive FSS is synthesized by a genetic algorithm code successfully. Genetic algorithm synthesis provides straightforward synthesis process compared to conventional method. Designed absorptive FSS is manufactured and frequency response is measured with WR‐90 waveguide setup. The measurement result of 1 dB transmission bandwidth is between 9.43 and 12.50 GHz with a minimum insertion loss of 0.65 dB.

Cost-effective horn antennas; from E-plane sectionalized to octagonal shapes

ABSTRACT In this paper, low-cost methods of improving horn antennas are studied based on the recently introduced E-plane sectionalized rectangular horn antennas. In the beginning, application of E-plane sectionalizing of the rectangular horn antennas on open-boundary E-plane sectoral horn antennas is reexamined and a simple method for obtaining high gain and low sidelobe levels (SLLs) is introduced. Subsequently, effects of removing the conductive sheets from the modified E-plane sectionalized horn antenna are studied and a simple horn antenna with octagonal aperture is obtained with slightly reduced efficiency. Finally, an ultra-low-cost method of improving simple rectangular horn antennas is introduced based on this study. The purpose is to compensate the destructive effects of high SLLs of reference antennas in the antenna measurements, since a common reference antenna type is the rectangular horn antenna, which has high SLLs on the E-plane. In particular, efficiency improvement and SLL reduction of rectangular horn antennas are achieved by adding only four triangular conductive sheets to construct octagonal horn antennas.

Design of compact slot antenna and octagonal blended shape antenna

ABSTRACT In this paper, two new compact halved-size single and UWB antennas are proposed for WiFi and UWB applications. The single-band compact halved size slot antenna is proposed for WiFi applications at 2.4 GHz. The resonant frequency of the conventional slot antenna can be reduced by cutting the antenna into two halves and without using any lumped elements inside the slot. Moreover, the impedance and radiation characteristics of the proposed halved-size antenna are suitable for WiFi applications at 2.4 GHz. The proposed WiFi antenna has a miniaturised size of 25 × 16.5 × 0.813 mm3. Then, an octagonal blended-shape antenna (OBSA) for UWB applications is proposed. The UWB band from 3.1 GHz to 10.6 GHz is encompassed by the halved-size OBSA using the same cutting concept. Furthermore, a grounded L-stub is added on the top side to improve the reflection coefficients. The proposed OBSA has a compact size of 28 × 13 × 0.813 mm3 with stable omnidirectional radiation patterns. Simulation and measured results are in good agreement.

Akulturasi Budaya pada Corak Bangsal Mandalasana dalam Objek Wisata Keraton Yogyakarta

There is a separate building that has a contrasting cultural style. Bangsal Mandalasana is a building in the form of a gazebo which functioned as a gathering place for musicians at that time. What is unique is that the styles of musical instruments implemented in this ward are not just traditional Indonesian music, but are musical instruments originating from the West and the Middle East. In fact, some of these instruments are modern musical instruments. It can be seen that there is a common thread between Western culture which has been merged outside the traditional culture of Hinduism, Buddhism and Islam.The aim of this research is to analyze how decorative patterns in cultural acculturation occur in the Mandalasana Ward building. So that we can draw a historical thread of the fusion of western and Javanese culture which became an accentuation of culture within the Ngayogyakarta palace environment.This research uses qualitative methods by producing descriptive data with a study focus on the Yogyakarta Palace tourist attraction by dissecting the cultural acculturation found in Bangsal Mandalasana ornaments.Ward Mandasana has an octagonal shape with an octagonal pillar structure which is also taken from the shape of gazebos in Europe in general. The base is made flat and uses a fence that is integrated with supporting pillars, which is different from other ward shapes in the palace environment. The ornamental style in this ward uses an unusual material, namely stained glass, where stained glass was used in building culture in the West starting in theGothic which was used to decorate the Cathedral windows in the 12th century. The motifs presented are also Western musical instruments which indicate the existence of Western concepts in Bangsal Mandalasana.
 Keywords: Cultural Acculturation, Bangsal Mandalasana Styles, Cultural Bangsal Mandalasana Styles

Functional performance of octagonal plan mosques-analysis of octagonal plan mosques in Mosul

The identity of Islamic cities is distinctly manifested through their congregational mosques, primarily characterized by their continuous and stable function, epitomized by the five daily congregational prayers. The performance of a mosque is intricately linked to a set of religious, organizational, structural, and economic determinants. and it is closely tied to the functional and architectural attributes of its elements and spaces. The historic congregational mosques in the Islamic world have predominantly adhered to the architectural model of the Prophet's Mosque, characterized by its rectangular form. In modern mosques, various factors such as technological advancements, and cultural and scientific influences have led to architectural trends and stylistic innovations. These innovations have aimed to enhance the efficiency and performance of congregational mosques, one of which is the octagonal form. The research problem centred on the utilization of the octagonal shape and its adaptability in the context of the congregational mosques in the city of Mosul and its suitability for optimal mosque functioning. The research sought to elucidate the appropriateness of employing the octagonal form in congregational mosques by analysing samples with octagonal layouts in Mosul to investigate the extent to which this form influenced the characteristics of the mosque. The research concluded that all octagonal layouts had undergone modifications and expansions to rectify the unsuitable layout, indicating that the octagonal form is foreign to the traditional mosque typology. Furthermore, it is subject to additional alterations to accommodate the functional and architectural requirements of the congregational mosque.

Clustering characteristics of Fe-rich intermetallics in high vacuum die cast AlSiMgMn alloys with high resolution μ-CT inspection

The AlSiMgMn alloys with different Fe and Mn contents were prepared with high vacuum die casting (HVDC) process. The Fe-rich intermetallics in the surface layer and center of the alloys were inspected with high-resolution 3D X-ray micro-computed tomography (μ-CT), and the growth mechanism of the primary Fe-rich phase was analyzed through their different 3D morphographies. By combining Bisecting K-means and DBSCAN (Density-Based Spatial Clustering of Applications with Noise) methods, the intermetallic clusters in the surface layer and center were quantified. The results show that the primary Fe-rich intermetallics were characterized as hexahedron and octagonal dendrite shapes with large size while the eutectic Fe-rich intermetallics were polyhedron and Chinese-script shapes. When Fe and Mn contents of the alloys were lower, the intermetallic clusters in the surface layer were with less cluster number and larger intermetallic distances showing uniform distribution whereas the clusters in the center were more and had shorter distances. In the case of alloys with higher Fe and Mn contents, the intermetallics showed clustering distribution in both the surface layer and center. The mechanism for the intermetallic cluster formation in the surface layer and center was further discussed.

Enhancing Efficiency of Solar Heater Box with Linear Actuator for Maximizing Solarization

Worldwide, stored grain pests are massively infesting most stored crops and their by-products. The main losses are due to infestation of these pests occurring on various carriers just prior to harvest, during storage or shipping. Methyl bromide and phosphine fumigation have been widely used for phytosanitary treatment of stored grains but are recognized as highly effective in depleting ozone, and similarly, residue-free grains are important for thermal disinfection. Solarization is one of the best ways to manage and disinfect crops, the traditional solarization methods are already practised by farmers but are inefficient to kill all stages of pests and require additional land exposed to the sun. In this work, thermal disinfection systems using solar heaters are proposed, designed, and developed to offset the actual lethal heat window. For the experiment work, the solar heater boxes were constructed in an octagon shape with 135o at the base for trapping maximum heat inside the solar the heater box. The characteristics of the proposed system proved simpler, faster, and inexpensive but equally effective to achieve the desired results in terms of heat generation and seed moisture.

Octagonal lattice-based triangulated shape descriptor engaging second-order derivatives supplementing image retrieval

Erstwhile shape description schemes lack primarily in establishing trade-offs with accuracy and computational load. Accordingly, a lightweight shape descriptor offering precise definition and compaction of high-frequency features is contributed in this paper using a simple geometrical shape for localization and shape characterization. Initially, the input image is octagonally tessellated and triangularly decomposed into sub-regions whose side-wise differences are evaluated and subjected to second-order differentiation to produce three high-frequency values representing triangle corners. The resultant is processed by the law of sines to yield localized shape features exhibiting congruence and is reiterated on the residual regions, followed by a novel octal encoding scheme encompassing maximal variations in the localized regions. The resulting features are globally fabricated into shape histograms in a non-overlapping manner representing the shape vector. This scheme validated on widely popular benchmark shape datasets demonstrates superior retrieval and recognition accuracies greater than 93% which is lacking in its competitors.

Evaluating the impact of wind effects on tall buildings with various plan shapes

Tall building is playing important role in the growth of urbanization and has resulted in developing to the vertical rise of the structure. The data available for the designing of the tall building is not sufficient or need some modification up to very limited extent in the present scenario. In this study a rectangular shape having L: B ratio as 1.15 and octagonal plan shape are selected to investigate the wind loads on building. The area of both models is nearly equal for the comparison of the results. Pressure effects are the main concern of considered building model. When it comes to predicting wind-related events on buildings or other structures, computational fluid dynamics (CFD) is a reliable and quicker option. CFD analysis is carried out using a software program called (ANSYS-CFX). This paper presents pressure contours that are calculated at the front, back & adjacent sides of the individual tall buildings. The results clearly show that based upon the building shape, the pressures generated can be either positive pressure or negative which can be either beneficial or can have adverse effects. The result on both the building model shows that the pressure on wind ward face is more or less the same and it does not depend on the shape of the building. In the case of a symmetrical building, the leeward face will always be subjected to the suction effect, while the side faces will always exhibit an equal pressure distribution.

“That’s Purely Greek”: Ethnicity and Gender in Ariadne Thompson’s The Octagonal Heart i

Abstract The Octagonal Heart (1956) depicts Ariadne Thompson’s memories of the happy summers she spent as a child with her extended family in the octagonal house, Parnassus, a private residence near St. Louis, USA. A strong sense of Greekness permeates the intertwining layers of the memoir, the physical one (the house with its Greek-style decorated rooms arranged in an octagonal shape and its surroundings) and the emotional one (which captures the relationships among the family members and their reactions to significant moments in their lives). This essay proposes a close reading of the memoir with a view to examining how gender, ethnic expectations, and attitudes towards assimilation have impacted the hyphenated identities of three generations of women in Thompson’s family.

The nonlinear analysis of tapered steel section with opening due to the effects of bending behavior

PurposeTapered steel sections are widely used in house building design due to their structural efficiency and aesthetic appearance. Due to the practical usage of web tapering specifications in the metal building industry, fabrication and material expenses are analyzed to achieve geometric and economic productivity. The purpose of this study is to investigate the effectiveness of utilizing web profiles with openings in reducing the weight of steel beams.Design/methodology/approachIn this paper, the nonlinear analysis of the bending behavior of a tapered steel section with an opening was studied by finite element analysis. The results were then compared with those of the tapered steel section without an opening in terms of displacement and yield moment.FindingsThe bending capacity of a tapered steel section was analyzed using finite element analysis. Results showed that the tapered steel section without openings had a higher bending capacity compared to the section with various sizes of web openings. The results also showed that decreasing the number of openings would increase the bending capacity, whereas increasing the size of the opening would decrease it. The difference in the yield moment between the tapered steel section with and without openings was only 15.818%. A total of 60 nonlinear analyses were conducted to investigate the effect of the number and size of web openings, flange thickness and web thickness on the bending behavior. However, this study showed that web opening with octagon shape and 0.6D size of web opening, where D is the depth of section, showed the best section in terms of yield moment and volume reduction compared to other opening size and shape.Originality/valueIt is also found that tapered steel section has better moment resistance in thicker flange and web. The study is valuable for engineers and designers who work with steel structures and need to optimize the performance of tapered steel sections with web openings.

Beam pattern control for graphene-based patch array antenna with radio-over-fiber systems by using modulation instability phenomenon

This paper presents a beam control system for a graphene-based phased array antenna (PAA) using the proposed radio-over-fiber (RoF) in the THz and sub-THz bands. The generated pulses are modulated by the Mach-Zehnder modulator (MZM) and, by using the special design of the fiber under modulation instability (MI), can be amplified at the sideband of the carrier. Finally, changing the length of the compensating fiber in the bit-control system makes it possible to control the PAA beam pattern. Improving the bias voltage (V π ) of the MZM, simplicity of the RoF system structure, and increasing the spontaneous gain caused by the MI phenomenon are the advantages of the proposed system. Therefore, it is an acceptable candidate for the beam control applications system. Also, the patch antenna is based on graphene and has a new structure. This antenna consists of radiation patches in an octagonal shape and a microstrip feed line. The antenna operates with appropriate radiation features, with gains of 12 dB and returns losses of less than -10 dB at 700 GHz bandwidth. All simulations are performed using the CST Microwave Studio and the Optiwave software.

Three-Dimensional Analysis of the Thermal Behavior of Alumina-Water Nanofluid Inside Hexagonal and Octagonal Enclosed Domain

The current work focused on the study of the laminar and steady free convection of Aluminum Oxide / Water nanofluid inside cavities. Two different cavities have the same volume but different overall surface area and count of walls are studied. These cavities are heated differentially on the vertical square side walls which of identical area and dimensions for both cavities. The other vertical walls of these cavities have hexagonal and octagonal shapes. The first cavity has eight walls while the second has ten walls. The study accomplished for solid particles volume fraction and Rayleigh number ranges of (φ = 0.01, 0.03, 0.05) and (103 ≤ Ra ≤ 106). The study interested highly by the effect of the cavity geometry parameters including the lateral cross section, the height, the number of walls on the flow and heat transfer. Other flow parameters are recognized on the fluid flow and heat transfer fields like the nanoparticles volume fraction and the Rayleigh number. The results indicated that the surface area increase by means the additional walls has an observed effect on guiding the results. Where the octagonal cavity has better enhancement in heat transfer especially at (Ra=104 and 105). The percent increase in Nu over the hexagonal cavity is (0.6, 0.8, 0.7, 0.3) for the specified Ra range.

MASJID RAYA AL-MASHUN MEDAN: Telaah Sejarah Sosial Keagamaan

The purpose of this study is how the history of the Al-Mashun Grand Mosque, the Al-Mashun Grand Mosque in the city of Medan in general has a mixed architectural form. It is divided into three: the main room, used as a place of prayer, the shape of the octagon is not equilateral. The left side (south-east) and the right side (north-east) of the main prayer room are surrounded by alleys (corridors). The shape of the dome follows the shape of Turkish architecture with a broken octagonal shape and an octagonal shaped plan with cylindrical columns at each of the corners of the marble. Research on MASJID RAYA AL- MASHUN MEDAN: A Study of socio-Religious History is relevant by using qualitative research because it meets the characteristics of qualitative research, especially in terms of in-depth data disclosure through interviews, observations and document studies of what informants do, how they carry out activities, what activities are carried out for and why they practice virtue or goodness (good morals) in the real reality.

Shape optimization of hanging structure using the concept of Biomimics

In the field of construction industry there has been a lot of newly adopted technology, one among that is hanging structures. Hanging structures can help reduce a lot of space as there are no direct columns supporting the sub structure and super structure. The usage of construction materials can be reduced thus making it economical compared to conventional buildings. The structural stability of hanging buildings depends on its shape and size. This idea led to incorporating the concept of bio mimics for optimizing the efficient shape of hanging structure from weaver bird’s nest. Bio mimics is the concept of emulating and iterating any naturally existing organism or element, it is the process of mimicking either the shape or mechanism of any naturally existing element. The weaver bird’s nest is lightweight in nature and also structurally stable against gravity and wind load. Two conventional hanging structure of Rectangle and Octagonal shape were selected for this study. The material adopted for numerical investigation using finite element software Abaqus v 6.14 is ferrocement because of its lightweight nature. The structure is hanged with the help of a connection wire which is hooked into it and a beam column that is fixed at bottom. The models are analyzed under the application of gravity, wind, live load for a fixed penetration length and by varying the diameter of the connection wire. Also, the hanging structure bio-mimicked from the shape of weaver bird’s nest is modeled and analyzed by applying same loading and boundary condition. The structural stability of conventional hanging structure is then compared to that of bio-mimicked hanging structure in terms of stress and deformation. From the results it is observed that bio-mimicked hanging structure is more stable compared to that conventional hanging structure.