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The restoration and strengthening of QT600 is an industry bottleneck challenge. The Co-12 cladding layer has great wear and corrosion resistance. The purpose of this paper is to quantitatively reveal the transient evolution law of the corrosion process of Co-12 cladding layer on QT600 surface.

In this paper, a three-dimensional numerical model of the corrosion process of Co-12 cladding layer by QT600 laser cladding is established. The interaction between pitting pits and corrosion medium is considered to reveal the transient evolution of ion concentration, electrode potential, pH and corrosion rate at different locations.

The calculation shows that the ion concentration in pitting pit changes Cl⁻>Co²⁺>Na⁺, pH value decreases from top to bottom and corrosion rate at bottom is greater than that at top. The electrochemical corrosion test of Co-12 cladding layer was carried out. It is shown that the current density of QT600 increases by an order of magnitude compared to the Co-12 cladding layer, and the corrosion rate is 4.862 times higher than that of the cladding layer.

The results show that Co-12 cladding layer has great corrosion resistance, which provides an effective way for QT600 protection.

There is a growing interest in applying the principles of biophilic design to hotel lobbies to enhance positive user experiences. However, there is little empirical research in this area, particularly for abstract or indirect biophilic approaches. The current study analyzed the biophilic strategy of “organized complexity” (which entails structured hierarchical patterns) in a hotel lobby in relation to attention restoration outcomes.

A virtual reality approach was used to create three lobby designs, differing only in their degree of organized complexity. A between-subjects study was conducted with 91 participants, evaluating reactions to the lobby designs in terms of perceived attention restoration, perceived environmental complexity and environmental preferences.

A strong positive relationship was found between participants' perception of environmental complexity and feelings of restoration. However, no statistically significant correlation was found between restoration and the objective measures of organized complexity. This suggests that individual preferences or baseline responses may play a crucial role in the benefits associated with this aspect of biophilic design.

The findings suggest a novel possibility – that responses to organized complexity may not be universal but may instead depend on an individual’s background and personal preferences. While the study found that perceived complexity was associated with restoration, the objective features of the environment that incited these perceptions were different for different participants. This indicates that more research is needed into potentially relevant personal factors.

The Ottoman cultural legacy in Algeria is made up of a diverse range of architectural structures. The Algerian government strategy in connection with the Ottoman old buildings is to restore them into museums. This study will attempt to present a contrastive analysis between two old palaces being under restoration (refurbishment), and the goal is to propose a museum route by calculating the ambiance aimed at circulating the rooms by visitors.

The authors analyzed the architectural components of the various entities by observing in situ and taking measurements for a single case study to get a sense of the results for the mid-season (spring and fall). The configuration was next evaluated by modeling the space syntax and combining it with a simulation of daylight luminance, for the period when the authors could not make measurements on-site. The ultimate goal is to combine these findings to suggest the ideal in-route for the future museum.

This research allowed the authors to propose a museum itinerary adapted to the new vocation of the palaces, which considers the daylight as an element of composition in the spaces of circulation.

The paper proposes solutions to a flow management problem encountered in several similar palaces converted into museums.

The study aims to raise questions on the museum, and to preserve such heritage from neglect by giving it a new life more adapted to the needs of the Algerian society.

The authors believe that this contribution will be a creative solution for issues related to the operation of palaces that have been converted into museums.

This study investigates the impact of the fire decay phase on structural damage using the sectional analysis method. The primary objective of this work is to forecast the non-dimensional capacity parameters for the axial and flexural load-carrying capacity of reinforced concrete (RC) sections for heating and the subsequent post-heating phase (decay phase) of the fire.

The sectional analysis method is used to determine the moment and axial capacities. The findings of sectional analysis and heat transfer for the heating stage are initially validated, and the analysis subsequently proceeds to determine the load capacity during the fire’s heating and decay phases by appropriately incorporating non-dimensional sectional and material parameters. The numerical analysis includes four fire curves with different cooling rates and steel percentages.

The study’s findings indicate that the rate at which the cooling process occurs after undergoing heating substantially impacts the axial and flexural capacity. The maximum degradation in axial and flexural capacity occurred in the range of 15–20% for cooling rates of 3 °C/min and 5 °C/min as compared to the capacity obtained at 120 min of heating for all steel percentages. As the fire cooling rate reduced to 1 °C/min, the highest deterioration in axial and flexural capacity reached 48–50% and 42–46%, respectively, in the post-heating stage.

The established non-dimensional parameters for axial and flexural capacity are limited to the analysed section in the study owing to the thermal profile, however, this can be modified depending on the section geometry and fire scenario.

The study primarily focusses on the degradation of axial and flexural capacity at various time intervals during the entire fire exposure, including heating and cooling. The findings obtained showed that following the completion of the fire’s heating phase, the structural capacity continued to decrease over the subsequent post-heating period. It is recommended that structural members' fire resistance designs encompass both the heating and cooling phases of a fire. Since the capacity degradation varies with fire duration, the conventional method is inadequate to design the load capacity for appropriate fire safety. Therefore, it is essential to adopt a performance-based approach while designing structural elements' capacity for the desired fire resistance rating. The proposed technique of using non-dimensional parameters will effectively support predicting the load capacity for required fire resistance.

The fire-resistant requirements for reinforced concrete structures are generally established based on standard fire exposure conditions, which account for the fire growth phase. However, it is important to note that concrete structures can experience internal damage over time during the decay phase of fires, which can be quantitatively determined using the proposed non-dimensional parameter approach.

This article summarizes the international scientific research output of global forest product models, infers future research trends and provides reference for quantitative analysis and mathematical modeling of Chinese forest product problems, with the aim of contributing to promoting domestic production of Chinese forest products and strengthening international trade competitiveness of forest products.

In 1999, Joseph Buongiorno, a scholar at the University of Wisconsin in the United States of America, proposed the global forest products model (GFPM), which was first applied to research in the global forestry sector. GFPM is a recursive dynamic model based on five assumptions: macroeconomics, local equilibrium, dynamic equilibrium, forest product conversion flow and trade inertia. Using a certain year from 1992 to present as the base period, it simulates and predicts changes in prices, production and import and export trade indicators of 14 forest products in 180 countries (regions) through computer programs. Its advantages lie in covering a wide range of countries and a wide variety of forest products. The data mainly include forest resource data, forest product trade data, and other economic data required by the model, sourced from the Food and Agriculture Organization (FAO) of the United Nations and the World Bank, respectively.

Compared to international quantitative and modeling research in the field of forest product production and trade, China's related research is not comprehensive and in-depth, and there is not much quantitative and mathematical modeling research, resulting in a significant gap. This article summarizes the international scientific research output of global forest product models, infers future research trends, and provides reference for quantitative analysis and mathematical modeling of Chinese forest product problems, with the aim of contributing to promoting domestic production of Chinese forest products and strengthening international trade competitiveness of forest products.

On the basis of summarizing and analyzing the international scientific research output of GFPM, sorting out the current research status and progress at home and abroad, this article discusses potential research expansion directions in 10 aspects, including the types, yield and quality of domestic forest product production, international trade of forest products, and external impacts on the forestry system, in order to provide new ideas for global forest product model research in China.

Several chaotic system-based encryption techniques have been presented in recent years to protect digital images using cryptography. The challenges of key distribution and administration make symmetric encryption difficult. The purpose of this paper is to address these concerns, the novel hybrid partial differential elliptical Rubik’s cube algorithm is developed in this study as an asymmetric image encryption approach. This novel algorithm generates a random weighted matrix, and uses the masking method on image pixels with Rubik’s cube principle. Security analysis has been conducted, it enhances and increases the reliability of the proposed algorithm against a variety of attacks including statistical and differential attacks.

In this light, a differential elliptical model is designed with two phases for image encryption and decryption. A modified image is achieved by rotating and mixing intensities of rows and columns with a masking matrix derived from the key generation technique using a unique approach based on the elliptic curve and Rubik’s cube principle.

To evaluate the security level, the proposed algorithm is tested with statistical and differential attacks on a different set of test images with peak signal-to-noise ratio, unified average changed intensity and number of pixel change rate performance metrics. These results proved that the proposed image encryption method is completely reliable and enhances image security during transmission.

The elliptic curve–based encryption is hard to break by hackers and adding a Rubik’s cube principle makes it even more complex and nearly impossible to decode. The proposed method provides reduced key size.

This study aims to propose a novel deep learning (DL)-based framework, iRelevancy, for identifying the disaster relevancy of a social media (SM) message.

It is worth mentioning that a fusion-based DL model is introduced to objectively identify the relevancy of a SM message to the disaster. The proposed system is evaluated with cyclone Fani data and compared with state-of-the-art DL models and the recent relevant studies. The performance of the experiments is assessed by the accuracy, precision, recall, f1-score, area under receiver operating curve and precision–recall curve score.

The iRelevancy leads to a better performance in accuracy, precision, recall, F-score, the area under receiver operating characteristic and area under precision-recall curve, compared to other state-of-the-art methods in the literature.

The predictive performance of the proposed model is illustrated with experimental results on cyclone Fani data, along with misclassifications. Further, to analyze the performance of the iRelevancy, the results on other cyclonic disasters, i.e. cyclone Titli, cyclone Amphan and cyclone Nisarga are presented. In addition, the framework is implemented on catastrophic events of different natures, i.e. COVID-19. The research study can assist disaster managers in effectively maneuvering disasters during distress.

The research aims to investigate the impact of thermo-mechanical aging on SBR under cyclic-loading. By conducting experimental analyses and developing a 3D finite element analysis (FEA) model, it seeks to understand chemical and physical changes during aging processes. This research provides insights into nonlinear mechanical behavior, stress softening and microstructural alterations in SBR compounds, improving material performance and guiding future strategies.

This study combines experimental analyses, including cyclic tensile loading, attenuated total reflection (ATR), spectroscopy and energy-dispersive X-ray spectroscopy (EDS) line scans, to investigate the effects of thermo-mechanical aging (TMA) on carbon-black (CB) reinforced styrene-butadiene rubber (SBR). It employs a 3D FEA model using the Abaqus/Implicit code to comprehend the nonlinear behavior and stress softening response, offering a holistic understanding of aging processes and mechanical behavior under cyclic-loading.

This study reveals significant insights into SBR behavior during thermo-mechanical aging. Findings include surface roughness variations, chemical alterations and microstructural changes. Notably, a partial recovery of stiffness was observed as a function of CB volume fraction. The developed 3D FEA model accurately depicts nonlinear behavior, stress softening and strain fields around CB particles in unstressed states, predicting hysteresis and energy dissipation in aged SBRs.

This research offers novel insights by comprehensively investigating the impact of thermo-mechanical aging on CB-reinforced-SBR. The fusion of experimental techniques with FEA simulations reveals time-dependent mechanical behavior and microstructural changes in SBR materials. The model serves as a valuable tool for predicting material responses under various conditions, advancing the design and engineering of SBR-based products across industries.

Steel-reinforced concrete-filled steel tubular (SRCFST) columns have been increasingly popular in engineering practice for the columns' excellent seismic and fire performance. Significant design progress guidance has been made through continuous numerical and experimental research in recent years. This paper tested and analysed the residual loading capacity of SRCFST columns under axial loading after experiencing non-uniform ISO-834 standard fire.

The experimental research covered the main parameter of heating conditions, 1-side and 2-side fire, through two specimens. Two specimens were heated and loaded simultaneously in the furnace for 240 min. After cooling, the columns were moved to the hydraulic loading system and loaded to failure to determine the columns' residual capacity.

The experimental results indicated that the non-uniform heating area plays an essential role in the overall performance of SRCFST columns, the increasing heating area of columns results in lower residual loading capacity and stiffness. The SRCFST columns still had a high loading capacity after heating and loading in the fire.

The comparison of experimental data against design results showed that the design method generated a 16% safety margin for S2H4 and a 39% safety margin for S1H4.

Mainstream narratives in Indian history do not delve into the checkered history of the west coast. The reasons for this are many, including a predominantly center-outwards viewpoint of historians. West coast has always been open to sea route influences aiding its diversity. However, the lack of natural defense against colonizers from the sea destroyed indigenous and personal heritage. Small town narratives include uprooting, lack of access to past heritage and new settlement creation. The heritage of this everyday landscape shaped by human grit is the subject of the study.

This qualitative ethnographic study includes document analysis, transect walking, architectural built form study, open interviews and participatory observations.

The motivations for heritage management can be grouped into economic, cultural and technological. From a financial point of view, the urban core studied is still relevant and sustainable. Likewise, the Krishna temple dominates the cultural discussion and architectural documentation as a religious center. However, the cultural heritage of business streets and the third motivation of building technology have been largely ignored. This disregard is evident from neglect and the pastiche use of monumental or ornamental styles alien to the region for restoration efforts.

“Heritage is personal and individual as well as collective and universal” (Mire, 2016). The Pete heritage is not just crucial for the communities they house but the town as a whole. Their nonimpervious nature means that they hold collective memories for everyone. Attention to memories and monuments will increase the possibilities of shared responsibility between various stakeholders (Swenson et al., 2012). Therefore, they should be seen as a part of the larger whole.

This paper argues for the recent global bottom-up approach in heritage management rather than the conventional established practices. Established heritage management focuses on the mainstream, royal or specific ethnic heritage in the Indian subcontinent. The heritage of the common person rarely has the grandeur of monumental architecture taken up for preservation by the state. As a result, societies' individual and collective heritage are at risk of rapid erasure under the pressures of modernization. Built forms are repositories of cultural information; therefore, a sustainable instrument for the preservation of everyday heritage can be created with culture as an actuator. This study looks at the narrative of the historical coastal small-town business core created by internal mass migration due to colonization.