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Precast prestressed hollow core (HC) floors are widely used in various applications within the construction sector. Such floors are usually designed as single, simply supported elements, although it is known that individual elements forming the floor interact with each other. This article presents the state of the art regarding load redistribution in HC floors in the light of experimental data, current analytical models and code provisions. While this phenomenon is widely known and recognized, only sparse, and often poorly documented experimental data are available, which represent the basis for the assessment and calibration of analytical models. Moreover, even though the available models and code provisions share similar assumptions, their outcomes are in some cases conflicting. Having recognized the existing knowledge gap, the authors outline future perspectives for the development of consistent analytical and numerical approaches supplemented by new experimental data. [ABSTRACT FROM AUTHOR]

High agility, maneuverability, and payload capacity, combined with small footprints, make legged robots well-suited for precision agriculture applications. In this study, we introduce a novel bionic hexapod robot designed for agricultural applications to address the limitations of traditional wheeled and aerial robots. The robot features a terrain-adaptive gait and adjustable clearance to ensure stability and robustness over various terrains and obstacles. Equipped with a high-precision Inertial Measurement Unit (IMU), the robot is able to monitor its attitude in real time to maintain balance. To enhance obstacle detection and self-navigation capabilities, we have designed an advanced version of the robot equipped with an optional advanced sensing system. This advanced version includes LiDAR, stereo cameras, and distance sensors to enable obstacle detection and self-navigation capabilities. We have tested the standard version of the robot under different ground conditions, including hard concrete floors, rugged grass, slopes, and uneven field with obstacles. The robot maintains good stability with pitch angle fluctuations ranging from -11.5° to 8.6° in all conditions and can walk on slopes with gradients up to 17°. These trials demonstrated the robot's adaptability to complex field environments and validated its ability to maintain stability and efficiency. In addition, the terrain-adaptive algorithm is more energy efficient than traditional obstacle avoidance algorithms, reducing energy consumption by 14.4% for each obstacle crossed. Combined with its flexible and lightweight design, our robot shows significant potential in improving agricultural practices by increasing efficiency, lowering labor costs, and enhancing sustainability. In our future work, we will further develop the robot's energy efficiency, durability in various environmental conditions, and compatibility with different crops and farming methods. [ABSTRACT FROM AUTHOR]

Context: Traditional smallholder pig farming plays an important role in farmers' income and national food security in the low- and middle-income countries in Southeast Asia including Laos; however, its productivity is low and it is often environmentally unsustainable. Aims: The objectives of this study were to evaluate the effects of using fermented bed-floor housing compared with the conventional concrete-floor housing on growth, carcass treats and economic return on raising Laos native pigs. Methods: The study was conducted at the Faculty of Agriculture, National University of Laos. Twenty four castrated native pigs, aged ±3 months with initial liveweight of 17 ± 2 kg/head, were randomly assigned to the following housing types as treatments: (1) conventional concrete-floor system (CS) as control, and (2) fermented bed-flooring system (FB). The pigs were fed with similar diet with 16.01% crude protein and 11,796 kJ/kg gross energy for a period of 84 days after a 14-day adaptation to the feed. Each treatment was replicated four times (pens), with three pigs/pen. Data on feed intake, liveweight change, carcass trait and costs and returns of production in the two treatments were analysed using Student's paired-sample t -test. Key results: Pigs kept in FB flooring had higher DM and nutrient (crude protein, crude fibre, ether extract and organic matter) intakes than did their counterparts raised in the CS, but the differences were not significant when adjusted to bodyweight basis. There were also no significant differences in growth performance (average daily gain (ADG) and feed conversion ratio (FCR)), and carcass traits, except that pigs from FB had higher hot carcass weight, dressing percentage and rib and bone weights. Native pigs kept in the FB system had significantly higher total production costs because of the cost of the bedding material, but also had four-fold higher net income return generated from the sale of the fermented floor compost. Conclusions: Fermented bed-flooring system has no significant impact on growth and key carcass traits, but significantly enhanced profit. Implications: Fermented bed-flooring system should be promoted for rearing local pigs under smallholder farms to increase profit and protect the environment in the low- and middle-income countries. Traditional indigenous pig farming using concrete floor has low productivity and is environmentally unsustainable. Fermented bed-flooring system enhances net profit by four fold through sale of the flooring compost. Fermented bed floor provides a profitable and environmentally sustainable option for smallholder pig farming in the developing countries. This article belongs to the Collection Sustainable Animal Agriculture for Developing Countries 2023. [ABSTRACT FROM AUTHOR]

Summary: In order to study the dynamic characteristics and human‐induced vibration response of light steel foamed concrete composite floor (LCSF), the vibration characteristics of 4.2 m × 5 m LCSF model were tested under the condition of opposite side support, and the natural vibration frequency of LCSF was obtained. The orthogonal anisotropic elastic plate and the simulated beam element were used, respectively, to compute the natural vibration frequency of the LCSF, and the estimated findings were compared with those obtained from measurements. The discrepancy between the calculated results and the measured results of the approximate beam element using the natural vibration frequency calculation technique is around 13%, but the error for the plate element using the calculated results and the tested results is about 23%. To examine the floor's vibration response under the factors of step frequency, walking path, pedestrian density, and load distribution, the LCSF underwent a human‐induced vibration test. The test results show that the fundamental frequency of the LCSF specimen is about 11 Hz, which can meet the requirements of the specification. However, the vibration response of the LCSF specimen under different conditions of pedestrian load is significantly different. With the acceleration of step frequency and the increase and concentration of load, the floor's vibration response becomes more visible. In the route test, it is established that LCSF has the attribute of a unidirectional plate. The natural vibration frequency of similar floor slab can be calculated by the method of simulating the natural vibration frequency of beam element. The findings can serve as a guide for LCSF research and implementation. [ABSTRACT FROM AUTHOR]

Summary: This study investigates the seismic impact of concrete floors on reduced beam section beam‐to‐column joints through four quasi‐static cyclic tests. We examine mechanical properties, failure modes, and processes against specific criteria. Additionally, we analyze hysteretic response, energy dissipation, stiffness, capacity, and stress–strain mechanisms. Moreover, the ABAQUS platform was used to reproduce the specimen nonlinear finite element model to compare and analyze the test results. The results showed that the specimens exhibit excellent energy dissipation capacity and ductility (with a coefficient of 5.00); the column‐bar connection characteristics affect the maximum capacity and plastic hinge behavior in the reduced beam area. The reduced section of beam's upper flange could not improve the overall seismic performance of the joint. The observed failure sequence is as follows: concrete floor cracking, beam flange yielding, reinforcement fracture, lower flange yielding in the reduced beam area, and overall joint failure. This sequence confirms that the joint fulfills the design criteria of a "strong column‐weak beam" by achieving the target of plastic hinge outward movement. [ABSTRACT FROM AUTHOR]

In this paper, we present a new parameterization and optimization procedure for minimizing the weight of ribbed plates. The primary goal is to reduce embodied CO2 in concrete floors as part of the effort to diminish the carbon footprint of the construction industry. A coupled plate-beam finite element model and its computational mesh enable simultaneous topology, shape and sizing optimization of ribbed plate systems. Using analytical sensitivity analysis and gradient-based optimization, we achieve significant weight reductions in the range of 24–57%, in comparison to reference designs with regular ribbing patterns. The results strengthen the argument in favor of ribbed plates as a structural system that can serve the environmental goals of the construction industry. While our focus is on ribbed concrete plates in buildings, the proposed mesh-based design parameterization is applicable in the general case of optimizing stiffened shells—with potential contributions also to automotive and aerospace applications. All computer codes used in this study are freely available through a public repository, . [ABSTRACT FROM AUTHOR]

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

This study focuses on the design procedure and development of the unbonded fiber-reinforced elastomeric isolator (UFREI) and its application to prevalent masonry building practices in developing countries. The proposed design procedure caters to the development of rectangular UFREIs with or without modifications, considering an improved shear behavior formulation. Afterward, the proposed design procedure is used to design the isolation system for a pre-existing base-isolated masonry building located in the Tawang district in the northeastern state of Arunachal Pradesh in India. Three different configurations of the above building [i.e., fixed base, isolated using square UFREIs, and isolated using modified rectangular UFREIs (MR-UFREI)] are considered for a comparative response analysis under a set of probable ground motions during a service period of 100 years. The building is modeled in SAP2000, where it is subjected to nonlinear time-history analysis under the considered set of ground motions. The masonry walls are modeled as nonlinear layered shell elements, and concrete floors as rigid diaphragms. An improved shear formulation of UFREI is used to model the isolation system as a combination of a multilinear elastic spring and a dashpot. Major response parameters, i.e., floor accelerations, isolator displacement, interstory drift ratio, etc., are investigated, and a significant improvement is witnessed throughout with the use of the MR-UFREI isolation system. The stress–strain distribution and concentrations in the masonry structure and isolation system are also investigated. These distributions are further used to quantify the fatigue losses to the elastomer layers used in the isolation system during the design period, which is found to be minimal. [ABSTRACT FROM AUTHOR]

Handling potatoes individually or collectively in packages can create opportunities for potatoes to develop quality defects including blackspot and shatter bruise. Three trials were conducted to examine how handling packaged potatoes can influence the risk for physical damage including shatter and blackspot bruise. An impact recording device was used to record peak acceleration (max g-force) in common fresh market packaging options (boxes or bales) at four drop heights (15 to 91 cm) on to three different surface types. When boxed potatoes were dropped onto concrete or a plastic slip, the potatoes on the bottom of the box had the highest risk of damage (greater than 100 g-force). When drop heights were lowered, or when cushioning material was added to hard surfaces (e.g., wooden pallet on top of concrete floor), the risk for impact damage was decreased throughout the box. When palletizing boxed potatoes, the risk of bruise decreased after the first layer was stacked on the pallet. Drop heights need to be below 15 cm, especially when making the first layer in a palletized stack of packaged potatoes to reduce potential bruising. The risk of high peak accelerations was not seen in the dropped or stationary bales for any of the drop heights examined. This study provided information for educating personnel on handling packaged potatoes and determining situations in which robotic stacking equipment needs to be adjusted to lower drop heights of packaged potatoes. [ABSTRACT FROM AUTHOR]

The conservation and repair of XX century architectural heritage built with reinforced concrete is becoming more and more important and requires suitable materials and technical solutions. In particular, effectiveness, compatibility and durability must be ensured, in spite of the limited extent of demolition allowed by the local authorities, and the literature in this field is still limited. In this paper, an experimental campaign was carried out in an historic reinforced concrete floor slab, where different repair mortars were used. After some on-site testing on the corrosion potential, the concrete beams of the slab were integrally cut and transported to the laboratory for a series of systematic tests, aimed at investigating the performance and compatibility of the repair materials, as well as any possible issues hindering the success of this structural intervention. The filling ability, physical compatibility, chemical compatibility and mechanical compatibility of the repair mortars and the corrosion behavior of the steel reinforcement were investigated, deriving some results of general interest, which may contribute to a better insight about the repair of heritage concrete floor slabs. [ABSTRACT FROM AUTHOR]

This article introduces the experimental and analytical research results of two precast insulation mortar concrete sandwich panels (PIMSP) and two precast concrete composite panels as one-way slabs under bending load. Obtaining a prefabricated floor slab that can balance thermal insulation and structural performance can reduce material consumption and increase inter-story usage height. As the sandwich material for PIMSP, insulation mortar with a strength of 6 MPa was used. Truss-shaped shear connectors were used for shear force transfer. Then, finite element analysis was used to analyze and study the unidirectional flat plate model. The results showed that the tested PIMSP achieved a complete composite effect in the elastic stage and a semi-composite effect in the plastic stage. The PIMSP crack pattern resembles that of a precast concrete slab when utilized as a one-way slab. The load transfer capacity of truss-shaped shear connectors is relatively small, and it is mainly used as a connection between floors. Experiments have demonstrated that PIMSP panels can serve as a structural substitute for regular concrete floors in residential buildings. [ABSTRACT FROM AUTHOR]

A captive‐bred polar bear was presented for investigation of a non‐healing wound, suspected to be traumatic in nature. Histopathological examination of cutaneous samples, taken while the bear was under general anaesthesia, was compatible with dermatophytic furunculosis. The bear was treated with systemic itraconazole (5 mg/kg once daily) for 3 months, alongside topical 2% miconazole nitrate and 2% chlorhexidine gluconate twice weekly. Environmental decontamination of concrete flooring and metal handling facilities was performed with a detergent to remove organic matter, followed by 1:10 dilution of 5% sodium hypochlorite solution at least twice weekly and between the use of the facilities by different bears. Within 4 months, the ulceration had resolved, and the lesion had reduced to a 10 cm diameter patch of complete alopecia. [ABSTRACT FROM AUTHOR]

The article titled "The Buford Highway Farmers Market" by Diamond Forde reflects on the author's memories of visiting the market with their family and the changes that occurred after a tragic event. The author describes the vibrant atmosphere of the market, with its diverse food offerings and friendly fishmonger. However, after a car accident, the author's grandmother's life became more isolated, with her only companionship being a television and religious programming. The author reflects on their promise to wear a leopard-print jacket that their grandmother bought but never got to see them wear. The article ends with the author finding joy and connection by wearing the jacket to a rock concert with their sister. Diamond Forde is an award-winning poet whose work has been published in various literary journals. [Extracted from the article]

A total of 9 real scale reinforced concrete shear walls were produced, 3 of them being the reference, representing the basement floor of a reinforced concrete building. These 9 shear walls produced, 3 wall are fully filled, 3 of them have window openings and 3 of them have door openings. The RC shear walls were exposed to displacement-controlled reversed cyclic lateral loading. In the experiments that damaged the experimental specimens, loads up to 0.5% story drift ratio for moderate damage and 1.0% story drift ratio for heavy damage were applied. Within the scope of the experimental study, the damage distributions of the tested nine RC shear walls were examined in detail, and the strengthening technique was developed using CFRP strip and CFRP fan-type anchors. The performance of damaged RC shear walls after using the devised repair method was analysed. The study's findings revealed that the repair method created by employing CFRP strips to restore moderately damaged RC shear walls with and without apertures was well enough successful in restoring the shear walls' performance levels. [ABSTRACT FROM AUTHOR]

The electrical resistivity tomography (ERT) method is often challenged by the presence of reinforced concrete (RC) in urban and industrial environments, because the embedded metallic wire mesh can severely distort the distribution of subsurface currents. We investigate one typical scenario in real applications, in which an RC floor overlays the natural topsoil or rock. Our synthetic forward simulations show that the embedded wire mesh behaves like a local good conductor in data of small source‐receiver separations and acts like an equal‐potential object that keeps the potential from decaying at large source‐receiver separations. Routine ERT inversions that ignore the RC cannot work properly because the thin and highly conductive wire mesh may be manifested as large uninterpretable low‐resistivity anomalies in the imaging results. Two remedies are adopted to improve the ERT resolution in such cases. First, we find a top layer with high conductivity in our model to adequately represent the wire mesh; then, we initiate the inversion with the top‐layer model as the starting and reference model. This warm‐start approach overcomes the difficulty of recovering the large conductivity contrast between metallic objects and regular earth materials. Second, underground electrodes are added to the survey array, so more information from depth can be obtained to fight against the dominance of current channelling in the wire mesh. Finally, our strategies are used to invert a real ERT dataset from an indoor manufacturing plant, where RC covers the entire floor of the building and electrodes are in contact with the soil through open holes in the floor. Our simulation and field data inversion verify our findings and demonstrate the effectiveness of our solutions in improving the resolution of ERT when the survey is carried out over RC floor in urban and industrial environments. [ABSTRACT FROM AUTHOR]

The paper focuses on tall timber buildings. The major aim of this paper is to identify the most sustainable and efficient structural system to increase the height of timber buildings, also considering steel–timber hybrid structures. First of all, a brief review of tall buildings' evolution is presented to understand why tall timber buildings are considered nowadays and which are the most adopted structural solutions. Then, the case study of the tallest timber building in the world is selected and utilized as an archetype. Once the model has been validated, seven alternative structural systems are considered by varying the horizontal load resisting system and preserving the same member cross-sections as the reference building. The variants are tested and compared in terms of material consumption, vibration characteristics and lateral load response. Using the best structural system, the height of the building is increased, pushing the structures beyond the current limits and identifying the most efficient option. The idea is to preserve the column cross-sections and balance the increase in gravity loads due to the additional floors by replacing the concrete floors with timber counterparts. With the same structural system, equivalent steel–timber hybrid solutions are finally tested and compared in terms of sustainability to timber-only counterparts and to the original project. The results of analyses show that the use of steel elements combined with timber can lead to optimized and sustainable structural solutions. [ABSTRACT FROM AUTHOR]

This study explores the potential use of new connections to shape precast building geometries, focusing on connection performance, robotic fabrication, and foldable structural elements. Three connection types, including coupled-bolts, hinges, and steel tubes, were initially proposed and assessed in beam and portal frame geometries. In contrast, the study introduces conceptual ideas; initial experimental and numerical studies were conducted to estimate connection capacities. Robotic fabrication for connecting elements to reused concrete and converting floor elements into beams was detailed, showcasing robotic technology's performance and potential. These connections were employed in designing new precast element geometries, ranging from simple beams to multi-story buildings. Geometric properties and volume quantities of folded and opened geometries were studied using 37 CAD models. To properly discuss the joint performance reference, monolithic elements with exact dimensions were created for comparison. Despite varied connection capacity ( 38 % to 100 % ), the steel tube exhibited the most desirable performance, resembling a monolithic element with an exact size. Some proposed foldable geometries showed a significant reduction (up to 7 % ) in element dimensions to facilitate transport and construction. [ABSTRACT FROM AUTHOR]

Based on the engineering background of weakly cemented roadways and adjacent chambers in Western China, a numerical simulation method was used to examine the changes in stress distribution and increment in the surrounding rock of weakly cemented roadways adjacent to chambers. The results show that the surrounding rock stress of the weakly cemented roadway adjacent to the chambers increases by approximately 30%. The vertical stress of the surrounding rock mainly expands along the vertical direction, and the expansion range is 7–12 times that of the chamber height. The horizontal stress of the surrounding rock mainly expands along the horizontal direction, and the expansion range is 3–6 times that of the chamber width. Based on the support idea of "allowable deformation" + "relief pressure" + "maintaining roadway shape", the support technology of weakly cemented roadways adjacent to chambers is established with "full section U-shaped steel shed + filling flexible materials between the steel shed and surrounding rock + patching the roof bolt + laying concrete on floor". An engineering test based on the above support technology was carried out, and it was found that the deformation of the weakly cemented roadway adjacent to the chambers was 0 in 20 days. [ABSTRACT FROM AUTHOR]

This article discusses the issue of reinforced concrete industrial floors being affected by subsoil swelling, which can lead to cracks and shifting. The main cause of this problem is the presence of swelling soil in the subsoil. The article provides regression relationships for predicting swelling pressure and deformation of these floors based on indirect measurements. It also offers a risk classification system for assessing the likelihood of surface damage due to subsoil swelling. The text emphasizes the importance of considering swelling during the design and construction of these floors. Additionally, the document explores methods for predicting soil swelling potential and presents prediction relationships for quantifying swelling pressures and deformations of reinforced concrete floors. Finally, it introduces a risk classification system for wire reinforced concrete surfaces based on variables influencing swelling. The text highlights the issue of industrial floors being susceptible to failure due to swelling soils and provides valuable information for predicting and assessing the risk of damage. [Extracted from the article]

Context: Tungiasis is a neglected tropical skin disease endemic in resource-poor communities. It is caused by the penetration of the female sand flea, Tunga penetrans, into the skin causing immense pain, itching, difficulty walking, sleeping and concentrating on school or work. Infection is associated with living in a house with unsealed earthen house floors. Methods: This feasibility study used a community-based co-creation approach to develop and test simple, locally appropriate, and affordable flooring solutions to create a sealed, washable floor for the prevention of tungiasis. Locally used techniques were explored and compared in small slab trials. The floor with best strength and lowest cost was pilot trialed in 12 households with tungiasis cases to assess its durability and costs, feasibility of installation in existing local houses using local masons and explore community perceptions. Disease outcomes were measured to estimate potential impact. Results: It was feasible to build the capacity of a community-based organization to conduct research, develop a low-cost floor and conduct a pilot trial. The optimal low-cost floor was stabilized local subsoil with cement at a 1:9 ratio, installed as a 5 cm depth slab. A sealed floor was associated with a lower mean infection intensity among infected children than in control households (aIRR 0.53, 95%CI 0.29–0.97) when adjusted for covariates. The cost of the new floor was US$3/m2 compared to $10 for a concrete floor. Beneficiaries reported the floor made their lives much easier, enabled them to keep clean and children to do their schoolwork and eat while sitting on the floor. Challenges encountered indicate future studies would need intensive mentoring of masons to ensure the floor is properly installed and households supervised to ensure the floor is properly cured. Conclusion: This study provided promising evidence that retrofitting simple cement-stabilised soil floors with locally available materials is a feasible option for tungiasis control and can be implemented through training of community-based organisations. Disease outcome data is promising and suggests that a definitive trial is warranted. Data generated will inform the design of a fully powered randomized trial combined with behaviour change communications. Trial registration: ISRCTN 62801024 (retrospective 07.07.2023). [ABSTRACT FROM AUTHOR]

Moisture transport properties of concrete are rarely determined, simply because it is difficult and time‐consuming. Most studies in literature are limited to cement paste and mortar. Translation of these properties to concrete are not straight‐forward. Recently, however, a few measurements are done, also on concretes with supplementary cementitious materials. An overview is given on various ways of theoretically describing the moisture transport properties of concrete, with different "moisture transport coefficients" and their interrelations. Methods of determining those properties are shown and their advantages and drawbacks are discussed. Available data in literature are summarized and compared. A recently developed test method, the tin‐can method, is described. New results are shown for concretes with SCMs. The method's possibilities to be used for short‐term tests of aging concrete are discussed. A few important applications where the moisture transport properties are decisive are presented: applying moisture‐sensitive flooring materials on concrete floor slabs and carbonation‐initiated reinforcement corrosion under varying climatic conditions. [ABSTRACT FROM AUTHOR]

Building new wedding halls has been flourishing as one of the catching investments in Sudan in recent years. These halls typically require large open spaces with no permeant partitions or furniture that reduces the superimposed dead load considerably. This paper presents an example of designing a reinforced concrete wedding hall floor, using two flooring systems, namely, flat slab and two way solid slab considering dancing induced dynamic load. Firstly an initial sizing based on only dead and live load was carried. The dynamic response was assessed following three methods: 1) the fundamental frequency limit; 2) equivalent static load; and 3) the acceleration limit. The results of the dynamic assessment has shown that a little to no-design alteration has to be made in the concrete flooring systems to satisfy safety. However, problems of vibration perception and comfort may require further structural adjustment to meet the acceptable level of vibration in the project specification based on the anticipating floor usage. [ABSTRACT FROM AUTHOR]

Most of the problems associated with open cracks in reinforced concrete industrial floors do not arise from technological indiscipline in the execution or exceeding the permitted floor load, but from the geotechnical profile beneath the floor. In the presence of swelling soil in the subsoil, the floors can then be shifted upwards by centimeters and create open cracks. This article describes regression relationships for the prediction of swelling pressure and deformation of reinforced concrete industrial floors based on indirect measurements. These relationships were obtained by evaluating a large database of measurements carried out by the company GeoTec-GS and the Czech Technical University in Prague using neural networks, multiple correlation, regression analysis, and sensitivity analysis. The article also presents the actual classification of the risk of surface damage of reinforced concrete floors due to swelling of the subsoil and an example of its application is given.

Intrinsic factors as well as environmental effects influence dairy cow activity. Due to a high prevalence of indoor housing in Germany, the stable flooring may be highly influential. Therefore, an accelerometer measured the activity of 91 Holstein-Frisian cows over 169 days, to validate, if there is a difference in dairy cow activity caused by different floorings (i.e. rubber and concrete flooring). Statistical analysis with an exponential model resulted a significant difference in daily activity, caused by the compared floorings (p < 0.01). A cows level of activity was reduced by days in milk and lactation number. This negative correlation was stronger on rubber flooring than on concrete. Thus, difference in dairy cow activity diminished with days in milk and over lactations. In general decreasing activity, could be the consequence of a change in dairy cow behavior within and across lactations. That this effect was higher on rubber, can be explained through more comfort for the locomotor of the cows. [ABSTRACT FROM AUTHOR]

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

Eighteen healthy Murrah buffalo calves of either sex aged 6-8 months, maintained at Buffalo Research Station (BRS), Venkataramannagudem (Andhra Pradesh, India), were randomly selected and housed in three separate pens for a period of 90 days, from August 2022 to October 2022. Calves of first, second and third group were reared on concrete flooring (T1), rubber mat flooring (T2) and soil flooring (T3), respectively. The overall mean rectal temperature (°F) differed significantly (P < 0.01) and followed a trend T3 < T1 < T2. The overall mean pulse rate and respiration rate also differed significantly (P < 0.01) and followed a trend T3 < T2 < T1. The overall mean skin health score of T1 (1.52 ± 0.04) was significantly higher (P < 0.05) than T3 (1.29 ± 0.04) and T2 (1.36 ± 0.05), which were statistically similar. The overall mean heel erosions of T1 (0.64 ± 0.07) were significantly higher (P < 0.05) than T3 (0.33 ± 0.07) but didn't differ from T2 (0.48 ± 0.08). In the last fortnight, the average hoof concavity score of T1 (1.00 ± 0.01) was significantly (P = 0.05) higher than T3 (0.33 ± 0.21), but didn't differ significantly from T2 (0.50 ± 0.22). The average hoof overgrowth score at the end of study was significantly (P = 0.05) higher in T3 (1.00 ± 0.01) than T1 (0.33 ± 0.21), but didn't differ significantly from T2 (0.50 ± 0.22). It was concluded that rubber mat and soil flooring is better than concrete flooring as they maintain the vitals in normal range and cause less damage to the skin and hoof health. [ABSTRACT FROM AUTHOR]

In ruminant animals, the use of molasses has benefits related to improved voluntary intake and increased production of short-chain fatty acids (SCFA) in the rumen, especially butyrate. Butyrate is closely related to gastrointestinal tract health, as it may contribute to the increase in the absorption area of the ruminal epithelium and improve the utilization of diet components, resulting in improved voluntary intake and immune response capacity in stressful situations, such as weaning. Hence, our objective was to assess the effect of sugar cane molasses on rumen fermentation characteristics in young beef finishing heifers. Newly weaned Nellore × Red Angus heifers (n = 12) averaging 238 ± 5.1 kg body weight (BW), were used. All heifers were housed in individual pens with concrete floors, covered feeders, and drinkers. The basal diet was 50 % concentrate, and consisted of corn silage, sorghum silage, ground corn, soybean meal, urea, and a mineral premix. The diet was provided twice daily at 0700 and 1600 h, allowing up to 10% in orts (as fed). The following treatments were evaluated: control (no addition of powdered molasses) or addition of 50 g/kg of diet [dry matter (DM) basis] of powdered molasses. The experiment lasted for a total of 80 d, including a 14-d adaptation period. On d 68 and 76, rumen fluid samples were collected both before and 4 h after the morning feeding using an oral probe coupled to a vacuum pump. The initial fluid samples were discarded to prevent saliva contamination. The rumen fluid was filtered through four layers of cheesecloth, and then pH was measured. Subsequently, samples were taken and stored in an ultra-freezer (-80°C) for subsequent SCFA analysis. The data were subjected to analysis of variance using the GLM procedure of SAS 9.4 (α = 0.05). Providing molasses increased ruminal pH compared with control heifers (P < 0.032). Adding molasses did not affect SCFA concentration (P > 0.90). Conversely, we detected an effect of molasses on SCFA molar proportion. The molar proportion of both acetate (P < 0.013) and butyrate (P < 0.012) were greater in heifers fed molasses than with controls. On the other hand, dietary molasses addition decreased (P < 0.001). the propionate molar proportion. This resulted in an increased (P < 0.002) acetate-to-propionate ratio in heifers fed diets containing molasses. In conclusion, providing sugar cane molasses enhances rumen fermentation characteristics in young beef finishing heifers. [ABSTRACT FROM AUTHOR]

Abstract This work aims the assessment of the dynamic structural response of reinforced concrete floors subjected to rhythmic human activities, based on the use of biodynamic models, in order to consider the people-structure interaction effect. Initially, an experimental modal analysis on the investigated floor , with dimensions of 16m x 35m, was performed, in order to identify and assess the global dynamic behaviour of the structure. In sequence, a finite element model was developed and calibrated through experimental results. After that, based on forced vibration analyses, the floor dynamic response was determined (displacements and accelerations). It is concluded that the biodynamic systems modelling induced significant attenuations on the structural response when compared to those calculated based on the use of traditional “only force” models.

To study the evolution of stress on the ring and segment interfaces during the construction process of the concrete encapsulation of the main arch ring in a rigid-frame arch bridge, alongside its impact on the ultimate load-bearing capacity of the main arch ring, a 1:10 scale model experiment was conducted by taking the 600 m Tian'e Longtan Bridge as the prototype. The key cross-section concrete strain data were collected during the entire construction process of the main arch ring via fiber-optic strain sensors, which were used to investigate the stress evolution at ring and segment interfaces. ANSYS APDL was employed to simulate the ultimate bearing capacity under various loading conditions of two different finite element models, which were, respectively, formed segmentally and by single pouring. The results revealed that (1) after the closure of the concrete encapsulation of the main arch ring, the concrete stress in the cross-section exhibits significant stress disparities. At the same cross-section, the level of the web concrete stress can reach 76% of the floor concrete stress, while the roof concrete stress level is less than 20% of the floor concrete stress. (2) At the junction of two adjacent work planes, there are considerable differences in the stress levels of the concrete on both sides. After the closure of the main arch ring, the intersegment stress ratios of the floor, web, and roof concrete are 60~70%, 40~60%, and 0~5%, respectively. (3) Loading conditions remarkably affected the ultimate bearing capacity of the main arch ring. Under mid-span loading and 1/4 span symmetrical loading conditions, compared to single-pour concrete encapsulation, the ultimate bearing capacity of the main arch ring with concrete encapsulated by segmented and ring-divided pouring decreased by 19.16% and 5.23%, respectively, compared to single-pour concrete encapsulation. This suggests that the non-uniformity of stress distribution in the concrete sheath can lead to reductions in the ultimate bearing capacity of the arch ring. [ABSTRACT FROM AUTHOR]

The main challenge in designing Light-Weight Concrete (LWC) is to adapt most of the design, production, and execution rules from normal-weight concrete. Carbon Fiber-Reinforced Polymer (CFRP) composites provide strength and stiffness to the composite system. This study investigated the stiffness of an LWC flat slab with CFRP when subjected to human-induced vibration. This was determined by finding the natural frequency of the slab and comparing it with the acceleration limit ratio (human perception of vibration) of 0.5% g. In most cases, vibration characteristics are examined using commercial software based on Finite Element Analysis (FEA) methods that are powerful tools, but the user needs to understand the underlying assumptions and methods implemented, especially for reinforced concrete floor systems where inherent attributes, such as cracking, play an important role in the determination of vibration characteristics. This study used Abaqus CAE. The main idea of this study was that such software cannot detect the behavior of cracks in structures over the years and the effect on frequencies, as stiffness depends on the modulus of elasticity and not on the moment of inertia. Therefore, the natural frequency equation has a component that constantly accounts for the level of cracking on concrete slabs. This component was theoretically determined with detailed calculations that are not provided in the Design Guide for Vibrations of Reinforced Concrete Floor Systems. Then, the constant that accounts for the level of cracking k1 was multiplied by the modulus of elasticity E and substituted in the latter's place in Abaqus to ensure the right behavior of the slab with and without CFRP. This study also investigated the properties of CFRP and how to represent it in the Abaqus. The numerical results showed good agreement with FEA and the acceptance criteria for walking excitations increased when using CFRP on a floor system. [ABSTRACT FROM AUTHOR]

Introduction: This research proposes an equivalent calculation method for vibration analysis of composite floor slab is proposed to effectively analyze the vibration of the profiled steel sheet-concrete composite floor (PSSCCF) prefabricated structure caused by high-speed trains. Methods: For this purpose, an equivalent calculation model of PSSCCF was established, and the railway environment vibration of the PSSCCF equivalent calculation model was verified through experiments. Besides, a finite element model of the track-subgrade-soil-prefabricated structure was established, and the influence of speed, axle load, and the soil properties on the railway environmental vibration of PSSCCF prefabricated structure was analyzed and compared. Also, the railway environmental vibration difference between PSSCCF and the cast-in-place reinforced concrete floor (CRCF) was analyzed. Results: The results indicate that the equivalent analysis method of composite floor slab proposed can effectively predict the environmental vibration caused by high-speed trains. [ABSTRACT FROM AUTHOR]

The post-mortem changes that take place during the decomposition of corpses are extremely complex and have been the subject of considerable research because of their obvious importance to forensic scientists. Considerable advances have been made in understanding the interplay of the various factors that influence decay, and the timescales over which they operate. Similarly, changes to the chemistry and microstructure of bones, post-skeletonisation, are of intense interest to archaeological scientists and the past few decades has seen tremendous advances in our understanding of how post-burial diagenesis may impact endogenous evidence within ancient and fossil bones. In recent years it has been postulated that the early stages of putrefaction of a body have a profound effect on the microstructure of bones and that these changes persist over archaeological timescales. One of the most important mechanisms for post-depositional degradation of bones is bacterial bioerosion. The question of the origin of the bacteria responsible, and why some archaeological bones are bioeroded while others are not, has received considerable attention in recent years. The assertion by some that the bacteria originate in the gut, and infiltrate bone tissues via the vascular network during the putrefactive stages of decay, has led to a number of claims as to what can be inferred by the presence, or absence, of bacterial tunnelling in bones. These claims include evidence for human mummification, identification of stillborns and infanticide, and animal sacrifices. Here we present evidence from SEM histological examinations of bones from field experiments using intact pig carcasses interred in brick lined tombs; a forensic case of a body exposed on a concrete floor for ten years; together with de-fleshed bones from freshly slaughtered cows buried in tropical soils for 1-10 years. None of the decomposing pig carcasses, nor the human corpse, showed any signs of bacterial tunnelling in their bones. By contrast, the de-fleshed bones buried directly in soils showed evidence of tunnelling after only one year and considerable tunnelling after ten years. Our results cannot support the "enteric hypothesis" that the bone tunnelling microorganisms that degrade buried bones originate in the gut microbiota but rather suggest that gut bacteria play no role in the post-mortem degradation of buried bones. It therefore follows that no conclusions about post-mortem treatment of human or animal corpses can be deduced from the presence, or absence, of microbial tunnelling in skeletonised remains from an archaeological (or forensic) context. [ABSTRACT FROM AUTHOR]

Background: Heat stress has a considerable effect both on animal welfare and production. Animals in heat stressreduceproductivity and reproductive performances and in extreme cases, it causes death. Methods: The experiment was carried out in Satkhira, a South-Western part of Bangladesh from July 2019 to June 2020 for 12 months period to investigate the year-round heat stress experienced by cattle raised in a Deep Bedded Pack System (DBP) compared to that raised on a concrete floor (CF) system in an open barn. A total of six dry cows (2.5 to 3 yearsold, Holstein-Friesian crossbred) were allotted into two groups with three replications. The deep bedded pack was prepared with rice husk. The heat stress was calculated by following an equation using temperature and humidity data. Result: Animals raised on a concrete floor were suffered moderate to severe heat stress for eight months in a year from March to October. Otherwise, animals on the DBP floor were suffered from moderate heat stress only for five months, from June to October in a year. No severe case was found on the DBP floor but severe heat stress was shown by animals on the concrete floor from July to September. Therefore, animals feel more comfortable in the DBP management system. [ABSTRACT FROM AUTHOR]

Background: The study was conducted to evaluate the effect of floor enrichment with rubber mattress of calving pen on prepartum calving behaviour of Tharparkar cow during the winter season. Methods: A total 28 Tharparkar cows were taken in study during winter season (November to March) and divided into two groups each contain 14 animals. One group placed in floor enriched with rubber mattress and other group kept on bare concrete floor calving pen. Preparturient behaviours like lying time, standing time, lying bout duration, number of lying bouts, rumination time, rumination bouts, self grooming and frequency of self grooming were evaluated on -12 hr, -7th day, -14th day and -21st day prepartum for period of 12 hr in a day. Repeated Meausures ANOVA was used for the analysis of the data. Result: It was found that lying time, lying bout duration was significantly more in rubber mattress group as compare to concrete floor. However, 12 hr before parturition standing time was significantly high compare to any other observational day within the group. Similarly, rubber mattress had positive effect on rumination time, lying duration and self grooming frequency as compare to bare concrete floor. It was concluded that rubber mattress had beneficial effect in calving pen of Tharparkar cow during winter season due to its softness and insulating property. It provided comfort and warmth to the parturient cows. which was evident by increase in rumination time, more lying duration and reduced self grooming frequency. [ABSTRACT FROM AUTHOR]

A Roman villa in the Barbaricum, 300 km from the Limes? First research results on the "Roman Station" at Buzovycja. In 2020–2021 a site of clear Roman origin was discovered near Buzovycja (Ukraine, Černivci region). First field research in 2020 already suggested the existence of buildings that were built according to Roman building traditions. Specific architectural remains have been identified in several places on the surface of the site. In addition to the usual finds of the Černjachiv culture, such accumulations also contained fragments of brick, mortar and stone. According to the results of a geomagnetic survey conducted in 2021, a promising anomaly in the central part of the settlement site was selected for test digging. The main task of the archaeological excavations that followed was to determine the architectural type of the object and to date it. The excavation revealed an area of buildings constructed of brick, stone and lime mortar. The width of the building was about 9.3 m, the possible length can be estimated at about 20 m. The exposed building floor was 1.4 m below today's surface level and was a „screed"of concrete mortar and limestone. In the central part of the building, three round bricks were discovered on the concrete floor, one of which was fixed in place. Complete blocks of bricks were found in places, with up to four layers and connected with lime mortar. A number of finds were recovered in the building. This included Černjachiv ceramics, Forlimpopoli amphorae, amphora stands, glass beads, an iron chain and other objects. The analysis of the finds and the remains of the building showed that the building dates back to the late Roman period (3rd – mid 5th century AD). The salvaged remains of the building ceramics and mortar indicate that it was built in the Roman architectural tradition. The presence of rectangular and round brick blocks in a layer of destruction suggests that the building had a hypocaust. Other archaeological finds from the Buzovycja-1 site belong mainly to the Černjachiv culture. According to the current state of investigation, the overall finding is interpreted as a local settlement with buildings erected in the Roman building tradition. [ABSTRACT FROM AUTHOR]

The dynamic response of building structures is an essential design consideration in building acoustics. However, building design is increasingly driven by sustainability goals. Floors can be optimized to reduce material consumption and corresponding carbon emissions, yet geometric changes may cause sound insulation and vibration problems. Although the dynamic performance of traditional floors is well established, the performance of non-traditional shapes is less understood. Before trusting the results of building simulations encompassing optimized floors, the dynamic results should first be validated experimentally. This paper details a numerical finite element analysis method to ascertain the dynamic response of four shaped concrete slabs, with experimental modal analysis used to validate the numerical results. The material properties in the numerical model are updated to match the experimental results. The findings support a computational framework for determining the dynamic response of shaped structures that can then be implemented in future large-scale building models. [ABSTRACT FROM AUTHOR]

The object of the study was concrete floors in a poultry house with different types of litter. The paper addressed the problem of reducing microorganism contamination of concrete floors in poultry houses to prevent biological corrosion. Corrosion of the surface of the concrete floor in the form of the formation of calcium oxalate monohydrate crystals was established by scanning electron microscopy; microscopic fungi: A. pullulans, F. sporotrichioides, and A. niger were detected. The TPD MS method established that concrete samples obtained in a room with straw lose moisture by 51.52 % more, with granules – by 342.42 % (р≤0.05), with shavings by 6.06 %, compared to control. CO from concrete samples is released less with sawdust litter by 86.40 %, with straw – by 83.49 %, with shavings – by 76.69 %, with granules – by 69.90 % (р≤0.05). The CO2 content in concrete samples from the room with sawdust was lower by 86.88 % (р≤0.05), with straw – by 55.73 %, with shavings – by 38.52 %, with granules – by 23.77 %, compared to control without litter. Microbiological studies have established that 48 hours after disinfection, the total number of colonies of microorganisms on a concrete floor with a sawdust litter likely decreased by an average of 90.19 %, straw – by 91.62 %, shavings – by 79.76 %, granules – by 82.88 % (р≤0.05), in the control – by 83.73 %. It can be argued that the disinfectant destroys microorganisms on the concrete surface regardless of the type of substrate. The peculiarity of the experiment was the use of scanning electron microscopy and TPD MS methods to study structural changes in concrete. The research is distinguished by the use of a powdered disinfectant to reduce microbial damage to a concrete floor with different types of litter. The results of the experiment could be used in the aggressive environment of poultry houses to reduce the impact on concrete structures. [ABSTRACT FROM AUTHOR]

This case study describes an evaluation of the existing conditions of a concrete floor in an industrial hall located in Poland. The areas requiring improvement due to poor workmanship, as well as the age of the floor, were identified. The second part of the study is devoted to the procedure of making an innovative epoxy coating modified with granite powder, which is based on the authors' previously published research. The analysis describes the effects of adding 10% to 60% (graded every 10%) of the powder. The primary aim of the tests was to obtain the highest possible pull-off strength. Compared to the reference sample, the highest increase in strength, 18%, was obtained with the addition of 20% granite powder. Moreover, resistance to thermal shock, one of the most important parameters of epoxy floors, was also analyzed and discussed. Standard coatings are typically not resistant to thermal shock, but the innovative coating proposed in this study allows for increased resistance by up to several dozen percent. The relationship between the amount of granite powder added and the limit value of thermal shock resistance is presented in the article. The novelty of the case study involves the proposal of a comprehensive procedure of renovating floors, including the assessment of their condition, the repair methods, their surface strengthening, and the presentation of the characteristics of the new coating. [ABSTRACT FROM AUTHOR]

Constant growth in the concrete floor sector claims new techniques to improve concrete performance and avoid undesirable issues. In this way, materials used in concrete floors are essential, and it is critical to investigate them. Therefore, this study evaluated the influence of surface hardeners on the surface hardness determined by the rebound hammer test of concrete floors prepared with distinct water/cement ratios, curing ages, and cement types. The control parameters of the concrete's production, including the compressive strength, flexural tensile strength, and bleeding tests were analyzed. In addition, data were assessed by multifactorial analysis of variance (ANOVA). Thus, hardeners increased the surface resistance of the composites, therefore reducing the chances of pathological manifestations occurring. Taken together, we demonstrated that hardeners improved the concrete surface prepared with all mixture proportions, but it was more significant when using the cementitious hardener and higher w/c content (0.6). [ABSTRACT FROM AUTHOR]

We aimed to investigate the extent to which the initial state generated by unexpected loads, such as explosions and impacts on the remaining structure, affects the dynamic response of the structure. The study used the orthogonal test method to obtain orthogonal table L25 (53) by combining five levels of each of the three factors of column removal time and initial velocity, and the initial displacement of the remaining structure under three failure scenarios of the corner, side, and internal columns at the ground floor of the reinforced concrete frame structure. The degree of influence of different factors on the structural dynamic response, and the result of the unifactorial impact of initial velocity and initial displacement of the remaining structure on the structural dynamic response in the case of failure of the bottom side columns, were obtained by the polar difference method. The results show that the analysis using the orthogonal test polar difference method revealed that the initial displacement has a more significant influence on the dynamic response of the structure, forming the main influencing factor. At the same time, the failure time and initial velocity have a smaller influence on the dynamic response of the structure as secondary influencing factors. In the case of unifactorial influence, the initial upward displacement and initial upward velocity are detrimental to the structure, leading to progressive collapse. In contrast, the initial downward velocity and initial downward displacement are favorable. [ABSTRACT FROM AUTHOR]

In this paper, the influence of post-consumer thermoplastic elastomer (TPE) additive derived from used car floor mats on the physical and mechanical properties of concrete is presented. Waste elastomer (fractions 0–2 and 2–8 mm) was used as a substitute for sand or fine aggregate in the amount of 2.5, 5.0, 7.5, and 10.0% by weight of cement. For all series, the physical and mechanical properties of concrete (for example, compressive strength, flexural tensile strength, water absorption, density, and frost resistance), as well as its microstructure, were tested. It has been shown that post-consumer elastomer waste from used car floor mats in the amount of 2.5% of cement weight can replace sand and gravel aggregate in concrete without reducing their mechanical strength and without changing their microstructure. The compressive strength (after 28 days) of concretes in which the waste was introduced as a substitute for sand and aggregate was 57.0 and 57.2 MPa, respectively (the strength of the control sample was 57.0 MPa). The use of post-consumer waste in concrete allows for a reduction in the consumption of natural aggregate (the addition of 2.5% of waste material saves natural aggregate approximately 20 kg/m3), which reduces the cost of concrete production and also has a positive impact on the environment (i.e., it saves cost and space in landfills, where currently used car floor mat are deposited). [ABSTRACT FROM AUTHOR]

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

The development of various construction robots can significantly reduce the construction labor intensity and risk. We present an experimental task of a truss construction robot, including automatic grasping and hoist positioning of concrete composite floor slab. And, a control strategy matching the construction robot is proposed to solve the following problems: (a) Due to the widespread manufacturing errors of building components, the position deviation of diagonal web reinforcement on concrete composite floor slab may cause grasping failure. (b) The chaotic surface of the floor slab seriously affects the recognition accuracy of the grasping target. (c) The large mass and inertia of heavy‐duty hanger and concrete composite floor slab make it difficult for robot to achieve accurate positioning under eccentric load condition. The machine vision recognition system ensures that if the diagonal web reinforcement is detected more than half of the grasping path, the grapple hook can change the grasping path independently to prevent it from colliding with the offset diagonal web reinforcement. An anticollision and grasping path planning method based on machine vision is proposed to improve the success rate and efficiency of automatic grasping. The mean value of proportional speed and proportional position is introduced as the evaluation speed and evaluation position of driving wheel to improve the accuracy of multiwheel synchronization. Moreover, we analyzed the robot performance from actual grasping and hoist positioning process of the concrete composite floor slab. The experimental results show that the robot has a good performance on the automatic grasping and hoisting of the concrete composite floor slab. [ABSTRACT FROM AUTHOR]

In a Finnish-Swedish consortium project, a large amount of sound insulation tests was conducted for several intermediate floors in laboratory conditions to serve various scientific research questions. The dataset contains 30 wooden and 8 concrete constructions which are commonly used between apartments in multistorey buildings. Impact sound insulation was determined according to ISO 10140-3 standard using both tapping machine and rubber ball as standard sound sources. Airborne sound insulation was determined according to the ISO 10140-2 standard. The data are special since they have a broad frequency range: 20−5000 Hz. Data are reported in 1/3-octave frequency bands and the single-number values of ISO 717-1 and ISO 717-2 are also reported. Detailed construction drawings are available for all reported constructions. The data are highly valuable for research, education, and development purposes since all data were obtained in the same laboratory (Turku University of Applied Sciences, Turku, Finland), and all the constructions were built by the same installation team.

A 2D stick model was developed to simulate sow walking on concrete floors. The model consisted of thirteen connective body joints to form a simple stick figure that approximates a sow's body skeleton. The video images of sows with reflective markers on their bodies walking along a corridor of concrete floor were analysed and translated into a 2D coordinate dataset. The motion of each landmark, including displacement, velocity and acceleration were calculated. A step of walking was modelled as three consecutive phases of motion: acceleration of foot leaving the ground; constant speed of foot swinging; and deceleration of foot touching the ground. One gait cycle was separated into several time steps and the movements of each joint at a time step in the horizontal (x) and vertical (y) directions were described by a combination of first and 2nd order polynomial functions. The coordinates of all joints were calculated in the x- and y-directions and these joints were then linked by synchronizing the motions of each joint at a given time step. The joint coordinates at each time step were then used to calculate a selected set of characteristic gait parameters, including the stride length and stance time for fore- and hindlimbs, diagonality, back angle and walking speed. Based on the comparisons of the predicted gait parameters between the lame and non-lame sows, the criteria were established for using the predicted gait parameters to detect sow lameness. The results showed an accuracy greater than 92% for lameness detection. • A 2D stick model was developed to simulate sow walking on concrete floors. • The model consisted of 13 joints and 12 sticks to represent a sow skeleton. • Joint movements were modelled by a 2nd order polynomial or a linear function. • The model predicted a set of parameters to characterize sow gait. • The model was used to detect lame sows with an accuracy over 92%. [ABSTRACT FROM AUTHOR]

Nonstructural components (NSCs) are the systems that are attached to the floors of a building structure. NSCs have become critical in sustaining post-earthquake functionality while constructing seismic-resilient structures. The seismic behavior of the NSCs primarily depends upon the behavior of the structure to which the NSC is attached. Building structures are subjected to earthquake loads and behave differently when the supporting soil type varies. In light of this, this study investigates the seismic demands on NSC attached to the floors of an elastic-reinforced concrete building frame supported by different soil types. The present study considered a regular building frame and a building frame with mass irregularity on the lower story. A total of 3 sets of 11 horizontal spectral-matched ground motions consistent with each soil type are considered. Floor response spectra (FRS) can be used to measure the seismic load on non-structural components. Primarily, it was found that the ordinates of FRS depend on the floor height, the vibration periods of the building, and the soil type. The presence of mass irregularity at the lower story amplified the floor response at all floor levels. Additionally, the values of floor spectral acceleration increase as soil flexibility increases. The amplification factors are critical for generating the floor response spectra, and their variation along the building height is discussed. The floor acceleration was found to vary non-linearly with the height of the building. Finally, artificial neural networks (ANNs) are employed to develop the prediction models for dynamic amplification factors. The results calculated by the dynamic time history analyses are utilized to validate the proposed prediction models. [ABSTRACT FROM AUTHOR]

The inevitable aging trend of theworld’s population brings a lot of challenges to the health care for the elderly. For example, it is difficult to guarantee timely rescue for single-resided elders who fall at home. Under this circumstance, a reliable automatic fall detection machine is in great need for emergent rescue. However, the state-of-the-art fall detection systems are suffering from serious privacy concerns, having a high false alarm, or being cumbersome for users. In this article, we propose a device-free fall detection system, namely G-Fall, based on floor vibration collected by geophone sensors.We first decompose the falling mode and characterize it with time-dependent floor vibration features. By leveraging Hidden Markov Model (HMM), our system is able to detect the fall event precisely and achieve user-independent detection. It requires no training from the elderly but only an HMM template learned in advance through a small number of training samples. To reduce the false alarm rate, we propose a novel reconfirmation mechanism using Energy-of-Arrival (EoA) positioning to assist in detecting the human fall. Extensive experiments have been conducted on 24 human subjects. On average, G-Fall achieves a 95.74% detection precision on the anti-static floor and 97.36% on the concrete floor. Furthermore, with the assistance of EoA, the false alarm rate is reduced to nearly 0%. [ABSTRACT FROM AUTHOR]

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

An analysis of an industrial lathe accident is presented in this paper. During operation, the rotating chuck lost its grip upon the cylindrical workpiece. The detached workpiece impacted the inside of the lathe cabinet, rebounded, struck the composite viewing window, and penetrated it. While observing the machining process through the window, the machinist was struck in the chest by the workpiece. He fell backward, suffering a severe traumatic brain injury when the back of his head impacted the concrete floor. The forensic analysis incorporated an event reconstruction to include an estimate of the ejection angle, velocity, and kinetic energy of the workpiece, the impact energy capacity of the window, and a failure analysis of the window and its frame. A kinetic energy analysis was performed by destructive testing of door/window replicas and high-speed videography. Impact testing of exemplar workpieces against alternative design highly impact-resistant windows was also performed [ABSTRACT FROM AUTHOR]