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The strengthening of existing columns using additional reinforced concrete (RC) jackets is one of the most popular techniques for the enhancement of a column's stiffness, load-bearing capacity and ductility. Important parameters affecting the effectiveness of this method are the strength of the additional concrete, concrete shrinkage and the connection between the old and the new concrete. In this study, the application of Ultra-High-Performance Fiber-Reinforced Concrete (UHPFRC) jackets for the structural upgrade of RC columns has been examined. Extensive numerical studies have been conducted to evaluate the effect of parameters such as the thickness of the jacket, concrete shrinkage and the addition of steel bars, and comparisons have been made with conventional RC jackets. The results of this study indicate that the use of UHPFRC can considerably improve the strength and the stiffness of existing reinforced concrete columns. The combination of UHPFRC and steel bars in the jacket leads to the most effective strengthening technique as a significant enhancement in the stiffness and the ultimate load capacity has been achieved. [ABSTRACT FROM AUTHOR]

Life cycle assessment (LCA) is highly needed and widely used to assess the environmental performance of circular economy (CE) measures such as reusing and sharing. However, the results of such LCAs are hampered by limited knowledge about the use phase of consumer products and oversimplification of important use phase aspects such as product functionality, user behavior, displacement, and rebound effects. This paper aims to validate the usefulness of a framework designed to assist practitioners in the generation and utilization of such knowledge in LCAs of circular measures. To validate the framework, a case study is used: reuse of shell jackets enabled by "premium secondhand" stores for outdoor equipment and clothing. The paper demonstrates that conclusions about the environmental performance of reuse can easily be altered depending on the functional unit definition, whether real user behavior data are used, and whether imperfect displacement and rebound effects are considered. For instance, shell jacket life cycles that include reuse and thus may be labeled "circular" have significantly higher environmental impact per use occasion than "linear" ones (used by one principal user the entire lifespan), since "circular" shell jackets are used less frequently, in particular during their first use span. Through facilitating the generation and utilization of environmentally relevant use phase data, which are otherwise often overlooked, the framework seems capable of supporting a better understanding of the environmental performance of CE measures. [ABSTRACT FROM AUTHOR]

The evolution of threats and scenarios requires continuous performance improvements of ballistic protections for armed forces. From a modeling point of view, it is necessary to use sufficiently precise material behavior models to accurately describe the phenomena observed during the impact of a projectile on a protective equipment. In this context, the goal of this paper is to characterize the behavior of a small caliber steel jacket by combining experimental and numerical approaches. The experimental method is based on the lateral compression of ring specimens directly machined from the thin and small ammunition. Various speeds and temperatures are considered in a quasi-static regime in order to reveal the strain rate and temperature dependencies of the tested material. The Finite Element Updating Method (FEMU) is used. Experimental results are coupled with an inverse optimization method and a finite element numerical model in order to determine the parameters of a constitutive model representative of the jacket material. Predictions of the present model are verified against experimental results and a parametric study as well as a discussion on the identified material parameters are proposed. The results indicate that the strain hardening parameter can be neglected and the behavior of the thin steel jacket can be described by a modeling without strain hardening sensitivity. [ABSTRACT FROM AUTHOR]

This paper presents an optimization tool for jacket structures to support Offshore Wind Turbines (OWTs). The tool incorporates several combinations of optimization algorithms and constraint-handling techniques (CHTs): Genetic Algorithm; Differential Evolution (DE); Tournament Selection Method; Multiple Constraint Ranking (MCR); Adaptive Penalty Method, and Helper-and-Equivalent Optimization. The objective function regards the minimization of the jacket weight; the design variables are the diameter and thickness of the tubular members. The constraints are related to natural frequencies and Ultimate Limit State criteria. The candidate solutions are evaluated by full nonlinear time-domain Finite Element coupled analyses. To assess the optimization algorithms and CHTs, a case study is presented for the standardized OWT/jacket structure from the Offshore Code Comparison Collaboration Continuation project. First, a numerical model is built and validated, in terms of masses, natural frequencies, and vibration modes; then, this model is employed to run the optimization tool for all combinations of optimization algorithms and CHTs. The results indicate that, while all methods lead to feasible optimal solutions that comply with the constraints and present considerable weight reductions, the best performer is the combination of the DE algorithm with the MCR constraint-handling technique. [ABSTRACT FROM AUTHOR]

Despite the ability of 3D convolutional methods to extract spatio-temporal information simultaneously, they also increase parameter redundancy and computational and storage costs. Previous work that has utilized the 2D convolution method has approached the problem in one of two ways: either using the entire body sequence as input to extract global features or dividing the body sequence into several parts to extract local features. However, global information tends to overlook detailed information specific to each body part, while local information fails to capture relationships between local regions. Therefore, this study proposes a new framework for constructing spatio-temporal representations, which involves extracting and fusing features in a novel manner. To achieve this, we introduce the multi-feature extraction-fusion (MFEF) module, which includes two branches: each branch extracts global features or local features individually, after which they are fused using multiple strategies. Additionally, as gait is a periodic action and different body parts contribute unequally to recognition during each cycle, we propose the periodic temporal feature modeling (PTFM) module, which extracts temporal features from adjacent frame parts during the complete gait cycle, based on the fused features. Furthermore, to capture fine-grained information specific to each body part, our framework utilizes multiple parallel PTFMs to correspond with each body part. We conducted a comprehensive experimental study on the widely used public dataset CASIA-B. Results indicate that the proposed approach achieved an average rank-1 accuracy of 97.2% in normal walking conditions, 92.3% while carrying a bag during walking, and 80.5% while wearing a jacket during walking. [ABSTRACT FROM AUTHOR]

This essay offers close analyses of the dust jacket illustrations for Hemingway's early Scribner publications (The Sun Also Rises, Torrents of Spring, and A Farewell to Arms). While these illustrations seem, at first glance, to have little to do with the books' narratives, themes, or styles, they serve at least two functions worth recovering. First, the illustrations work to locate Hemingway in literary and cultural traditions whose values were understood and largely shared by the mainstream book-buying American public in the 1920s. In addition, informed by the discourses of paratextual theory and book studies, I argue that they are influential early interpretive readings by the jacket designer, interpretive thresholds informed by the illustrator's own understanding of the texts and their value. [ABSTRACT FROM AUTHOR]

High‐Performance Fibre‐Reinforced Concrete (HPFRC) jacketing technique provides a sustainable solution to the constantly growing infrastructure degradation. This paper investigates the effect of HPFRC jacketing solution on strength enhancement of plain concrete. The experimental work included 23 samples, 15 of which were jacketed with HPFRC, and the remaining 8 were used to measure the unconfined strength. The key parameters were jacket thickness (25 mm, 35 mm, and 45 mm) and pre‐damage level (40% and 80%). The results show that jacketed columns exhibit a ductile behaviour. It is found that a 25 mm HPFRC jacket increases the compressive strength by 31%. Moreover, increasing the jacket thickness further enhances the compressive strength. However, the enhancement rate gradually decreases with increasing the jacket thickness. The results from sensor technology used on each concrete layer revealed that the lateral strain of jacketed concrete at a given axial strain was greater than that of unjacketed concrete, indicating an increased rate of dilation for the jacketed concrete. The results show that strengthening of existing columns at their mid‐service life (i.e., 40% pre‐damaged) is as effective as strengthening of new columns. The obtained knowledge suggests that HPFRC jacketing solution has a great potential to revolutionise infrastructure rehabilitation techniques. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the existing thermal insulation test methods and evaluation standards of clothing fabrics cannot intuitively and fully reflect the thermal insulation performance of clothing products in actual use, the cooling rate method was adopted to construct an environmental climate simulation chamber and a warm body dummy system, and the warm dummy was used to objectively test down jacket clothing at a certain ambient temperature. The objective test results were verified by the subjective evaluation of the thermal performance of down jacket garment and the infrared thermal imaging test. The results show that the thermal property and cooling rate of the garments are inversely proportional under different simulated ambient temperatures. Through subjective evaluation and infrared thermal imaging verification, a set of evaluation system that can intuitively, comprehensively and accurately reflect the thermal performance of down jacket garment under different environmental conditions is constructed, which can meet the specific requirements of producers and consumers for the thermal performance of clothing, which has strong theoretical and practical significance. [ABSTRACT FROM AUTHOR]

The strengthening of existing columns using additional reinforced concrete (RC) jackets is one of the most popular techniques for the enhancement of a column’s stiffness, load-bearing capacity and ductility. Important parameters affecting the effectiveness of this method are the strength of the additional concrete, concrete shrinkage and the connection between the old and the new concrete. In this study, the application of Ultra-High-Performance Fiber-Reinforced Concrete (UHPFRC) jackets for the structural upgrade of RC columns has been examined. Extensive numerical studies have been conducted to evaluate the effect of parameters such as the thickness of the jacket, concrete shrinkage and the addition of steel bars, and comparisons have been made with conventional RC jackets. The results of this study indicate that the use of UHPFRC can considerably improve the strength and the stiffness of existing reinforced concrete columns. The combination of UHPFRC and steel bars in the jacket leads to the most effective strengthening technique as a significant enhancement in the stiffness and the ultimate load capacity has been achieved.

High-speed motorized spindle is an important component of machine tool, and the influence of heat and deformation generated in the working process on the machining accuracy cannot be ignored. In order to reduce the temperature of the motorized spindle in the machining process, this paper first explores the influence of the flow rate of the motorized spindle cooling water on the cooling water jacket and the overall temperature change. The results indicate that when the flow rate exceeds a certain range, the overall temperature no longer drops, so there is an optimal flow rate in the choice of flow rate. Secondly, to solve the problem of uneven axial temperature distribution of the traditional spiral water jacket, four kinds of cooling water jackets with different structures were proposed. The simulation results show that the difference in temperature distribution inside the serpentine water jacket is small, the overall temperature was reduced by 1.8 °C and the pressure drop was reduced by 62.54 kPa. It shows that the serpentine cooling water jacket has better cooling performance and can effectively reduce the thermal deformation of the motorized spindle shafting, so as to achieve the purpose of improving the machining accuracy. [ABSTRACT FROM AUTHOR]

For decades, ferrocement has been used to repair, strengthen, and even build structural components because it is a long-lasting and reasonably priced material. However, onsite ferrocement jacketing is time-consuming and labour-intensive. Alternatively, prefabricated ferrocement jacket installation eliminates these shortcomings. Therefore, this study utilises wearable prefabricated ferrocement jackets to repair and strengthen axially loaded sub-standard low-strength concrete elements. In order to repair cracked specimens and strengthen existing intact specimens, two types of wearable prefabricated jackets are proposed, 'L' shape and 'U' shape. Besides a control specimen, two preloaded and two unloaded square concrete specimens were utilised to repair and strengthen using the Prefabricated Ferrocement Jacketing system. The test results and crack patterns show that all the jacketed specimens performed better than the control specimens in terms of load-bearing capacity, ultimate axial and lateral deflection, and ductility. In terms of load-bearing capacity, the unloaded strengthened specimens showed significant results consistently. Based on the results, the proposed solutions were found to be effective in solving the problem of typical square ferrocement jackets. [ABSTRACT FROM AUTHOR]

Structural health monitoring (SHM) has been recognized as a useful tool for safety management and risk reduction of offshore wind farms. In complex offshore environment, jacket structures of offshore wind turbines are prone to damages due to corrosion and fatigue. Effective SHM on jacket structures can substantially reduce their operation risk and costs. This work reviews the latest progress on the SHM of offshore wind jacket structures. The achievements in the structural damage identification, location, quantification, and remaining useful life (RUL) estimation are respectively introduced in detail, and existing challenges are discussed. Possible solutions to the challenges using the Digital Twin (DT) technology are put forward. The DT is able to mirror a real jacket structure into a virtual model, and Bayesian updating can refresh the virtual model parameters in real-time to keep consistency between virtual model and physical structure; then, just-in-time SHM can be carried out for jacket structures by performing damage detection, location, quantification, and RUL estimation using the virtual model. As a result, the DT may provide engineers and researchers a practicable tool for safety monitoring and risk reduction of fixed foundation offshore wind structures. [ABSTRACT FROM AUTHOR]

Electrical losses are converted into thermal energy in motors, which heats each component. It is a significant factor in decreasing motor mechanical performance. In this paper, the motor cooling characteristics were analyzed according to the design factors of the water jacket to investigate the cooling performance of a permanent magnet synchronous motor (PMSM). First, the electrical losses generated in PMSM were calculated using electromagnetic finite element (FE) analysis. Secondly, a 3D electromagnetic–thermal fluid coupled FE analysis was performed to analyze the temperature distribution inside the motor by applying electrical loss as the heat source. Finally, the motor cooling performance according to the design factors of the water jacket was statistically analyzed using the design of experiment (DOE) method. It was found that the mass flow rate of 0.02547 kg/s and six passes of the water jacket with one inlet and two outlets could be considered the optimum conditions in terms of the maximum motor temperature. [ABSTRACT FROM AUTHOR]

Aiming at improving the cooling of motor annular water jacket, the effects of different water jacket designs and pump rotation speed and epoxy resin filling on the flow field characteristics and motor temperature distribution were studied. Results show that uneven flow distribution leads to high temperature of motor coil and large temperature gradient. The optimized water jacket has better flow, uniform flow distribution of long and short paths, higher utilization rate of coolant, and the coil temperature is 2 °C lower than that of original model. On the basis of optimized water jacket, when epoxy resin filling methodology and pump rotation speed increased to 5000 r/min are applied, the coil temperature can be reduced by 16 °C compared with the original model. From the cooling performance optimization results in current case, the improvement order from the smallest to the biggest is the optimization of motor water jacket flow field, optimization of motor water jacket system flow rate, and the epoxy resin filling. To meet the cooling demands of motor, the comprehensive effects from the aspects of reducing coolant system resistance, increasing pump speed, epoxy resin filling and other effective technologies are ought to be considered for all case studies. [ABSTRACT FROM AUTHOR]

Reinforced concrete (RC) structures are frequently employed in construction owing to their versatility, strength, and durability. However, these structures can be vulnerable to fire incidents, which can significantly compromise their structural integrity and load-carrying capacity. In the aftermath of a fire, damaged RC columns often necessitate rehabilitation to restore their strength and functionality. The present study intends to carry out a numerical investigation of the behavior of reinforced concrete (RC) columns after their exposure to fire. As a first step, the study examined the effects of exposing the columns to fire for different periods (15, 30, 60 and 90 minutes) on the column's residual load-bearing capacity by considering some decisive geometrical parameters such as the column height and its cross-sectional area. The second step consisted of investigating the effectiveness of the strengthening techniques utilized by adding reinforcement and incorporating composite jackets, where each method used three external concrete compressive strength values, 25, 30, and 40 MPa, in order to improve the post-fire behavior of these columns. The results showed that the longer the column is exposed to fire, the lower its bearing capacity. However, it was also found that increasing the column cross-sectional area can reduce the percentage of load-bearing capacity. Moreover, A simple equation with sufficient accuracy has been proposed to predict the bearing capacity of reinforced columns. Finally, it was revealed that the strengthening methods used herein allowed restoring the capacity of the columns exposed to fire, but the strengthening technique using a composite jacket with steel plates showed better results in terms of strength. Where this technique allowed, it restored the capacity of the columns exposed to fire for a period of one hour by up to 182%. [ABSTRACT FROM AUTHOR]

Life cycle assessments of circular economy measures (CE LCA) of consumer products have been criticized for oversimplifying important aspects of the use phase such as user behavior and rebound effects, limiting our understanding of the environmental performance of circular economy measures. This study tests the usefulness of a framework designed to facilitate accounting for such aspects, by applying the framework to a case study of reuse of shell jackets enabled by "premium secondhand" outdoor stores. Methods for collecting use phase data were user surveys and interviews with store managers. Using the framework on this case study generated several novel insights which are interesting in themselves and as inputs to CE LCA. For instance, secondhand shell jackets have a significantly lower frequency of use during their first use span compared to the second and to shell jackets in the linear reference scenario. This implies that reuse in this case does not function as a mere use extension of otherwise similar use phases as is commonly assumed. The generation of such insights, which hitherto have been lacking in CE LCAs, points to the usefulness of the framework as a tool for opening the "black box" of the use phase in CE LCAs to improve understanding of the environmental performance of circular economy measures. [ABSTRACT FROM AUTHOR]

The Dingling Mausoleum was built as the afterlife abode of Emperor Shenzong of the Ming Dynasty (r. 1573–1620) and his two wives. Among the thousands of burial goods excavated from the site are two embroidered silk jackets that belonged to Imperial Honored Consort Wang, often referred to as Empress Dowager Xiaojing. With their physical proximity to the deceased body, sophisticated craftsmanship, and unusually festive motifs of one hundred playing boys, the jackets are both fascinating and puzzling. Through closely attending to the visual and material aspects of the jackets, and considering them together with the funerary context and historical circumstances, this paper suggests that these jackets were designed not only to serve the deceased in her afterlife, but also to maintain and strengthen her connection with her offspring in the living world as a means of power assertion and political protection. [ABSTRACT FROM AUTHOR]

Christian Richard "Dick" Schaare Jr. (pronounced Shar) was arguably New Jersey's most prolific and perhaps greatest pulp artist of the 20th century. His iconic artwork would grace hundreds of book covers, dust jackets, comic books, magazines, cigar boxes, calendars, milk cartons, and advertisements for more than 40 years from the 1920s to the 1960s.1 His pulp fiction artwork is well-known except for 18 dust jackets commissioned by the A. L. Burt Company for their Boy Scout fiction series books published in the mid to late 1920s. That he illustrated these dust jackets, brimming with action, adventure, and drama, has been largely forgotten by time, but they highlight his iconic pulp fiction style early in his career. [ABSTRACT FROM AUTHOR]

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Due to the almost linear textile chain, large amounts of non-renewable resources are consumed to produce cheap clothes that are only worn a few times. Particularly problematic are the fiber waste and the enormous water consumption of the textile industry. In this work, the development process of an outdoor jacket from the fiber to the finished product is sustainably presented. In the literature research, special attention is paid to fibers from waste and innovative processing methods. The practical part of the report describes the production of the convertible jacket design with the corresponding zero-waste pattern. The aim is to provide creative impulses and food for thought on the sustainability of a garment and to show that it is possible to produce a fashionable, durable, and water-repellent sustainable outdoor jacket. [ABSTRACT FROM AUTHOR]