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In a class of high quality (Q-) factor dielectric resonators with low radiative losses, including popular whispering-gallery mode (WGM) resonators with high azimuthal mode numbers, due to high confinement of modal field in dielectric, the Q-factor is limited by the value of inverse dielectric loss tangent of dielectric material. Metal enclosures necessary for device integration only marginally affect the Q-factor while eliminating the residual radiative loss and allowing the optimization of input and output coupling. While very high Q-factors ∼ 200 000 are available in sapphire WGM resonators in X-band, at millimeter wave frequencies increasing dielectric loss limits the Q-factor to much smaller values, e.g. ∼50000 and ∼25000 for quasi-TE and quasi-TM modes, correspondingly, at 36 GHz. The use of distributed Bragg reflection (DBR) principle allows to push modal energy outside dielectric while also isolating it from Joule losses in metallic enclosure walls. Very high Q ∼ 600 000 > --> t g δ has been demonstrated in X-band [C. A. Flory and R. C. Taber, IEEE Trans. Ultrason., Ferroelectr., Freq. Control 44, 486–495 (1997).] at the expense of impractically large dimensions. In this work, we report on the assembly and testing of a compact Ka-band sapphire distributed Bragg reflector cavity characterized with Q-factor seven times larger than one predicted by the material's dielectric loss at the frequency of interest. An intrinsic Q-factor of ∼ 200 000 is demonstrated at 36 GHz for the lowest order TM-mode of a sapphire DBR. The resonator has 50 cm 3 volume, smaller than previously demonstrated DBRs. [ABSTRACT FROM AUTHOR]

Achieving a correct cooling in glass manufacturing is very important to obtain the desired level of stresses and to avoid breakage. Numerical simulations can be used to optimize the cooling parameters. Such simulations have to be multiphysical coupling thermics and mechanics. Moreover, since glass is a semitransparent material, radiative effects inside the glass have to be taken into account. The present paper is devoted to numerical study of the cooling of a glass square plate on a metallic frame. To this end, the commercial software Abaqus was used to model the thermomechanical behavior of glass using adapted subroutines and was combined with an in-house C++ tool developed to solve the Radiative Transfer Equation. During and at the end of the cooling, weak areas in the glass plate are revealed by the simulation. Depending on the case studied, taking accurately the radiative effects into account leads to difference of residual stresses which can reach 10 MPa in certain cases. [ABSTRACT FROM AUTHOR]

The control and improvement of heat transfer in enclosures is very important in several engineering applications. In the current two-dimensional numerical study, the mixed convection and entropy generation of water flowing inside a square vented enclosure that contains four vibrating cylinders with relatively low frequencies fr = 1, 2, 3, 5 Hz in the vertical and horizontal directions are reported. The effects of Reynolds and Richardson numbers, vibration frequency, vibration amplitude, and the direction of the cylinders' vibration on heat transfer and entropy generation are presented for various cases. The horizontal walls of the enclosure are kept adiabatic while the vertical left and right walls are hot and cold, respectively. The linear regression analysis was used to reveal the rate of increase in the Nusselt number with the Reynolds and Richardson numbers number for each cases. Series of analyses show that the existence and the vibration of the cylinders increases heat transfer but the vibration in the horizontal direction is more effective since the top and bottom walls of the enclosure are adiabatic. It is found that the entropy generation due to heat transfer is low at the center of the enclosure. The direct relationship between the heat transfer and both Reynolds and Richardson numbers is reported. In terms of heat transfer, it is found that the critical vibration frequency and amplitude are fr = 4 and A = 0.05L and 0.075L. [ABSTRACT FROM AUTHOR]

AbstractThe mixed convective transport in a vertically shear-driven square cavity with a rotating circular porous cylinder is investigated numerically in two dimensions. This study aims to enhance the understanding of heat distribution within a closed environment containing intricate electronic systems and heat exchangers by employing a porous media modeling approach. The vertical walls of the enclosure are kept isothermal, while both the horizontal walls are assumed to be adiabatic. Upward progress is being made by the left wall at a constant translational speed. The porous circular cylinder is inserted within the square cavity concentrically, which is then rotated both clockwise and counter-clockwise. While the Reynolds number based on the motion of the lid is maintained constant at Re = 100, the porosity of the cylinder fluctuates in accordance with the Darcy number range 10−6 ≤ Da ≤ 10−2 The streamline and the isotherm patterns for a range of controlling factors, including the Richardson number (0.5 ≤ Ri ≤ 10) and the dimensionless rotational speed (−5≤Ω≤5) are used to show how the flow and the thermal fields within the enclosure evolve. Additionally, the entropy generation is calculated and compared for the above mentioned parameters. The irreversibility generation as well as the flow and the heat transfer phenomena are observed to be significantly influenced by the rotation and the porosity of the cylinder. [ABSTRACT FROM AUTHOR]

This article discusses the discovery of mud-brick structures in the Tausret Temple concession in Egypt. The structures, labeled Features 5 and 7, were found beneath a later funerary enclosure and are believed to be part of a single structure. The mud-brick structure is approximately 14 meters long and 3.25 meters wide, with two niches or rooms built into it. The function of the structure is unclear, but it may have been part of a mud-brick enclosure wall for the New Kingdom temple. The structure was later reused during the Third Intermediate Period and the Late Period for funerary purposes. Several faience objects and stamped mud bricks were found in the vicinity of the structure, as well as wooden furniture pieces. The text also discusses clusters of ceramics found in different areas surrounding a mud-brick structure in the TC area. The clusters contain a variety of pottery, including storage jars, incense burners, and offering vessels, dating from the New Kingdom to the Byzantine Period. Some clusters are associated with specific periods, such as the Saite-Persian Period, while others show a mix of ceramics from different periods. The assemblages suggest possible cultic activity and may be related to embalming practices during the Saite Period. The ceramics found in TC78 are unique and may indicate an earlier date than the other clusters. The text further discusses the discovery of two mud-brick structures at the Tausret temple complex. The first structure [Extracted from the article]

The occurrence of safety incidents for existing glass curtain walls (EGCWs) pronounced menace to the security of both lives and property. Undertaking safety assessment for EGCWs carries essential practical significance. However, current fuzzy evaluation methods overlook the uncertainty of indicator weights and the intricacies of rank attribution. In response, this paper proposes a novel approach to the safety assessment of EGCWs. This research establishes a framework of evaluation indicators for EGCWs and divides the safety ranks of each indicator into four tiers: Safe, Mild risk, Moderate risk, and High risk. Quantitative and qualitative indicators are quantified via the variable fuzzy cloud algorithm and cloud model. The information cloud combination weighting method is introduced to determine the weight clouds of indicators. Finally, a two-dimensional assessment result is derived using an improved fuzzy comprehensive evaluation method and fuzzy entropy. The exemplified outcomes demonstrate that this approach captures the safety status of evaluation subjects based on risk ranks, and fuzzy entropy addresses two issues: inconsistent level attribution and the comparison of identical risk ranks. The appraisal method further unveils the safety details of EGCWs, with findings that align consistently with the actual situation. [ABSTRACT FROM AUTHOR]

This study presents a novel, deep‐learning‐based model for the automated reconstruction of a cross‐sectional drawing from stereo photographs. Targeted cross‐sections captured in stereo photographs are detected and translated into sectional drawings using faster region‐based convolutional neural networks and Pix2Pix generative adversarial network. To address the challenge of perspective correction in the photographs, a novel camera pose optimization method is introduced and employed. This method eliminates the need for camera calibration and image matching, thereby offering greater flexibility in camera positioning and facilitating the use of telephoto lenses while avoiding image‐matching errors. Moreover, synthetic image datasets are used for training to facilitate the practical implementation of the proposed model in construction industry applications, considering the limited availability of open datasets in this field. The applicability of the proposed model was evaluated through experiments conducted on the cross‐sections of curtain wall components. The results demonstrated superior measurement accuracy, compared with those of current methods of laser scanning or camera‐based measurements for construction components. [ABSTRACT FROM AUTHOR]

In order to increase energy efficiency and user comfort, double skin façade designs are becoming increasingly popular in the built environment as an alternative to traditional façede and curtain walling systems. The vertical cavity between the outer and inner skins of double skin façade systems, which is critical for natural ventilation, can destroy the effectiveness of façade designs by creating fire hazards due to the creation of uninterrupted areas between spaces. It is essential for the sustainability of the buildings to make appropriate fire safety designs for the risks of spreading toxic gases released in a possible fire through the double skin façede cavity to monitor the design before the building is built and to take the necessary precautions. Therefore, that paper developed a numerical model using computational fluid dynamics to monitor the smoke propagation through the cavity of the double skin façade and the temperature changes in the building. As a contribution to the physical modeling studies of double skin façade systems in the literature, the effect of changing the slope of the outer skin on smoke propagation and temperature changes was investigated. A design model was created by developing 9 scenarios: 4 wide angles, 4 acute angles, and a right angle, each with an angle varying by 3 degrees. While acute-angle cavity designs increased the flue effect in the cavity and increased the direction speed and density of the smoke towards the cavity, wide-angle cavity designs reduced the ambient temperature. [ABSTRACT FROM AUTHOR]

In engineering practice, creating window openings in partition infill walls is a common requirement for infilled frames. However, the intervention of infill walls may interrupt the desired cyclic behavior of the infilled frame, and worst yet, the inevitable window opening might further aggravate such negative interaction. To protect the openings from the detrimental multiple diagonal struts mechanism of the traditional infill wall with a window opening under lateral loadings, this research presents a novel infill wall system with a window opening for semi-rigid steel frames. Three half-scaled specimens are subjected to quasi-static cycle tests: a bare steel frame, a steel frame infilled with a traditional infill wall with a window opening, and a precast infill wall with a window opening and sliding joints in a steel frame. Experimental results show that the proposed infill system with a window opening can release adverse crack development or opening deformation of the window opening by mitigating the detrimental multiple diagonal struts effect in conventional infill walls with window openings under lateral loadings. In this way, the developed infilled frame exhibits similar cyclic behavior to the designed bare steel frame with higher energy dissipation capacity. Furthermore, parametric analysis results reveal that the friction factor of the sliding joints has a significant effect on enhancing the bearing capacity of the proposed infill system, while the change of opening sizes and locations of the window opening has negligible impact on the cyclic behavior of the developed infill system. [ABSTRACT FROM AUTHOR]

Despite decades of intense research, whether the transformation of supercooled liquids into glass is a kinetic phenomenon or a thermodynamic phase transition remains unknown. Here, we analyzed optical microscopy experiments on 2D binary colloidal glass-forming liquids and investigated the structural links of a prominent kinetic theory of glass transition. We examined a possible structural origin for localized excitations, which are building blocks of the dynamical facilitation theory—a purely kinetic approach for the glass transition. To accomplish this, we utilize machine learning methods to identify a structural order parameter termed "softness" that has been found to be correlated with reorganization events in supercooled liquids. Both excitations and softness qualitatively capture the dynamical slowdown on approaching the glass transition and motivated us to explore spatial and temporal correlations between them. Our results show that excitations predominantly occur in regions with high softness and the appearance of these high softness regions precedes excitations, thus suggesting a causal connection between them. Thus, unifying dynamical and thermodynamical theories into a single structure-based framework may provide a route to understand the glass transition. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing interest in the use of sandwich panels that, beyond handling well-known bending stress, can withstand torsional stresses. This is particularly relevant for wall applications when the panels are equipped with photovoltaic or supplemental curtain wall modules. This research article presents a detailed exploration of the structural behavior of eccentrically loaded sandwich panels, with a specific focus on warping torsion. Experimental and numerical studies were conducted on polyisocyanurate (PU) core sandwich panels, commonly employed in building envelopes. These studies involved various dimensions and material properties, while omitting longitudinal joints. The experimental study provided essential insights and validated the numerical model in ANSYS. Enabling parametric variation, the numerical analysis extends the analysis beyond the experimental scope. Results revealed a high degree of correlation between experimental, numerical, and analytical solutions, regarding the rotation, as well as the normal and shear stress of the panel. Confirming the general applicability of warping torsion in sandwich panels with certain limitations, the study contributes valuable data for applications and design of eccentrically loaded sandwich panels, laying the foundation for potential engineering calculation methods. [ABSTRACT FROM AUTHOR]

Nowadays, glass curtain wall systems have been widely applied. There are many examples where these systems are applied to buildings with inclined facades. Inclined curtain walls are generally designed without considering the energy consumption values of the building. This situation affects the comfort conditions of the building users and the energy consumption of the building negatively. In this study, the effect of the curtain wall slope angle change on energy consumption was investigated. A building model was created with the DesignBuilder energy simulation program. The energy consumption values of the models with different curtain wall angles were calculated. In the study, the effect of the orientation of the inclined glass curtain wall was also examined. The cooling loads of the building in hot climate are higher than the heating loads. When the glass curtain wall is facing towards the south, the annual cooling loads increased by 7%, 15% and 22%, respectively, with the decrease of the facade angle from 90° to 80°,70°,60°. In addition, when the glass curtain wall is facing towards the south, the annual cooling loads decreased by 9%, 17% and 23%, respectively, as the facade angle increased from 90° to 100°, 110° and 120°. In the study, it was observed that the angle and direction of the glass curtain wall affects the solar energy gain, heating and cooling loads, and primary energy consumption values of the building. [ABSTRACT FROM AUTHOR]

This study addresses the challenges of designing sustainable structures that minimize energy consumption and costs. It introduces a novel optimization algorithm, the Developed Multi-Verse Optimization Algorithm (DMVO), to overcome the limitations of existing simulation software. The DMVO algorithm optimizes structure envelope parameters, such as walls, windows, and glass curtain walls, to achieve lower energy consumption and construction costs. It outperforms other methods, such as EHO, SAR, LSO, and MVO, in terms of energy efficiency and cost-effectiveness. Moreover, it converges to the optimal solution in fewer iterations, reaching the best result in the 65th iteration. It obtains the minimum values of envE and envL as 12,397,493.7 RMB and 48.7673 kWh/m2 y, respectively. The proposed algorithm enhances natural ventilation and internal lighting by increasing the glass curtain wall and window areas. It demonstrates its superior performance in saving energy in structures compared to other methods, achieving approximately a 38% reduction in total costs compared to the initial design. This research provides a promising method that can be generalized to various structure types and climates in future projects, contributing to the advancement of sustainable construction practices. Overall, the DMVO algorithm is a significant contribution to the field of sustainable structure design, offering an effective approach to improve energy efficiency and cost-effectiveness while reducing environmental impact. [ABSTRACT FROM AUTHOR]

Glazed curtain wall systems have become indispensable particularly in office buildings due to their light weight, aesthetic appearance, easy installation, and resistance to climate conditions. Curtain walls, however, also have problems in terms of thermal efficiency because of their wide, glazed windows and metal frames that have high thermal conductivity. The aim of this study is to offer proposals for improving the thermal performance of an office building with a glass curtain wall system built in a hot-humid climate zone. An office building constructed in Antalya, Turkey was modelled with the help of DesignBuilder energy simulation software, and various modifications were made to the model in order to improve the thermal performance of the building. With the improvements proposed in the study, it is possible to decrease the annual thermal loads of the whole building by 6.6%, and the annual thermal loads of the space with the curtain wall by 33.2%. The study revealed that applying an additional skin is more effective than lowering the U-value of the glass of the curtain wall in terms of thermal performance improvement. [ABSTRACT FROM AUTHOR]

The continuous growth of residential buildings has led to increasing attention on energy consumption and emission reduction. Taking an old residential building in Zhengzhou as an example, this article used Dest-h to simulate and calculate its energy-savings. A nine-factor, three-level orthogonal table was designed to analyze factors such as external wall heat transfer coefficient and building orientation, to understand the impact of different factors on energy savings. The results showed that among the 27 orthogonal experiments, the cooling consumption of experiment 23 was the lowest (21,236 kWh); the heating consumption of experiment 20 was the lowest (11,376 kWh); experiment 25 had the lowest total energy consumption (37,416 kWh). The comprehensive energy-saving rate was 36.12%, 43.29%, and 49.02%, respectively, in experiments 23, 20, and 25 as compared to the existing building. The annual energy-saving benefits were 6.57 yuan/m², 7.87 yuan/m², and 8.91 yuan/m², respectively. Among the nine factors studied, the heat transfer coefficients of the external wall and window had the greatest impact on the energy savings of this building. In the case of minimum total energy consumption, the heat transfer coefficient of the external wall was 0.6 W/(m²·K), and that of the external window was 0.8 W/(m²·K). The results prove the reliability of Dest-h in building energy conservation research, and it can be applied to practical research on energy consumption and emission reduction. [ABSTRACT FROM AUTHOR]

This study was conducted to survey the level of technification of quail sheds in Brazil. Data from 25 quail farms (5 in each Brazilian region) were collected by image analysis of videos available on the Internet. The analyzed variables were farm location, degree of technological adoption in quail sheds, housing conditions, structural conditions, wall conditions, and thermal comfort equipment. The data were subjected to descriptive analysis, and differences were assessed using the chi-squared test (p < 0.10). It was found that curtain walls were the most used system for air entry and renewal in quail sheds. Fan systems were present in only 12% of sheds, and evaporative cooling systems (or air conditioning) were observed in 4% of sheds, exclusively on large farms. Internal insulation was used in 20.83% of farms. In conclusion, Brazilian quail sheds have a low degree of technification; about 90% do not use implements such as ceiling, ventilation, and cooling systems. These conditions make it difficult to control environmental variables within quail sheds, impairing thermal comfort and, consequently, animal welfare and quail productivity. [ABSTRACT FROM AUTHOR]

This paper describes the use of cold and hot composite forming technology to produce pointed curtain wall profiles. An electromagnetic–temperature coupling model was constructed using ANSYS to study the temperature and electromagnetic field distribution during the forming process. Numerical simulation was used to optimize the process parameters to obtain the optimum heating parameters with a current of 4000 A, a frequency of 35 kHz, and a duration of 2 s. The accuracy of the model was also verified through experiments. The simulation results show that the use of a conductive magnet can improve the induction heating efficiency, increasing the heating frequency and the temperature peak; however, it also increases the temperature difference. Sharp-corner curtain wall profiles were successfully produced using the optimized process parameters. The temperature of the heating zone was measured using an infrared thermal imager, and the relative errors between the maximum heating temperature obtained from the simulation and the actual measured values were 5.37% and 5.02%, respectively, indicating that the finite element model performs well in terms of prediction. [ABSTRACT FROM AUTHOR]

A numerical study of mixed convective heat transfer in a lid‐driven square enclosure containing a hot elliptic cylinder is conducted. The impacts of the Grashof number (103≤Gr≤106) $({10}^{3}\le {Gr}\le 1{0}^{6})$, Reynolds number (1.0≤Re≤100) $(1.0\le Re\le 100)$, cylinder tilt angle (0°≤ϕ≤90°) $({0}^{^\circ }\le \phi \le {90}^{^\circ })$, and aspect ratio (1.0≤AR≤3.0) $(1.0\le AR\le 3.0)$ have been examined for a fluid of Pr $Pr$ of 0.71. The horizontal enclosure walls are insulated, while its vertical walls are restricted to a nonvarying temperature Tc, whereas a sinusoidal temperature of Th+∆T sin(πx/L) ${T}_{h}+\unicode{x02206}T\unicode{x0200A}\sin (\pi x/L)$ is imposed on the wall of the elliptical cylinder. The governing equations are solved using COMSOL Multiphysics 5.6 software. The fluid dynamic and the heat transport profiles between the enclosure and the elliptical cylinder walls are represented by the stream function, isothermal contours, and average Nusselt number. Results established that for all the considered aspect ratios, the thermal heating range of 103≤Gr≤104 ${10}^{3}\le {Gr}\le 1{0}^{4}$ is predominantly a conduction mechanism. The critical position of the ellipse where the inclination effect becomes insignificant is determined by the Grashof number and aspect ratio when the Re = 100. The strength of vortices and cell numbers are significantly influenced by the aspect ratio, particularly when the Gr=104 ${Gr}=1{0}^{4}$. When AR=1.0 $AR=1.0$, the average heat transfer from the cylinder remains the same regardless of the cylinder's orientation. The impact of cylinder orientation on heat transfer from the cylinder wall is minimal for 1.5≤AR≤2.0 $1.5\le AR\le \phantom{\rule{}{0ex}}2.0$. For AR values of 2.5≤AR≤3.0 $2.5\le AR\le \phantom{\rule{}{0ex}}3.0$, increasing the inclination angle does not result in improved heat transfer. The influence of the increasing inclination angle on the right wall diminishes as the angle increases, except when the Grashof number is greater than 105, where the rate of heat transfer is enhanced for inclination angles beyond 45°. [ABSTRACT FROM AUTHOR]

In recent years, construction engineering technology has been developing rapidly, and the application of curtain walls inside modern buildings is also increasing. However, with the increasing number of curtain wall orders, most factories are facing challenges in the market due to low productivity caused by a low balance rate of curtain wall production lines. This paper is useful in improving the balance rate of the curtain wall production line; firstly, we use the improved genetic algorithm to obtain the optimal sequencing scheme of the curtain wall production line. Then, the optimization plan is validated through FLEXSIM simulation, and the results show that the device utilization rate of each workstation reaches 80%. Finally, this paper designs an intelligent production factory for curtain walls, and then builds an intelligent production line for curtain wall columns for experiments. The experimental results show that the workstation operation time has been reduced from 360 s to 300 s; the production line balance rate has increased from 57.04% to 91.60%. Therefore, it can be concluded that the modified genetic algorithm is valid in improving the balance rate of curtain wall production lines and raising the production efficiency of enterprises. [ABSTRACT FROM AUTHOR]