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During the operation of the drill string, it displays a degree of flexibility. Simultaneously, its dynamic properties, influenced by complex stress conditions, manifest nonlinearity and uncertainty. A comprehensive investigation into the dynamics of flexible drill strings is imperative for deep well drilling. This paper presents a model that simulates random interactions between a flexible drill string and the borehole wall, simplifying the actual drill string model using analogous principles. Dynamic simulation software is utilized for analysis, and an indoor experimental setup has been established. The results reveal that with a constant weight on bit (WOB), higher drill string rotational speeds correlate with increased susceptibility to buckling deformation. Additionally, the critical time for deformation onset exhibits a nearly linear relationship with rotational speed. Maintaining a constant rotational speed, an increase in WOB enhances the likelihood of buckling deformation. The experimental findings suggest a correlation between the drill string's rotation frequency and the WOB. [ABSTRACT FROM AUTHOR]

Point clouds captured using laser scanners mounted on mobile platforms contain errors at the centimetre to decimetre level due to motion distortion. In applications such as lidar odometry or SLAM, this motion distortion is often ignored. However, in applications such as HD mapping or precise vehicle localisation, it is necessary to correct the effect of motion distortion or ‘deskew’ the point clouds before using them. Existing methods for deskewing point clouds mostly rely on high frequency IMU, which may not always be available. In this paper, we propose a straightforward approach that uses the registration of consecutive point clouds to estimate the motion of the scanner and deskew the point clouds. We introduce a novel surface‐based evaluation method to evaluate the performance of the proposed deskewing method. Furthermore, we develop a lidar simulator using the reverse of the proposed deskewing method which can produce synthetic point clouds with realistic motion distortion. [ABSTRACT FROM AUTHOR]

The dynamics of milling circuits, particularly those involving Semi-Autogenous Grinding (SAG) mills, are not adequately studied, despite their critical importance in mineral processing. This paper aims to investigate the dynamic behavior of an SAG mill pebble recycling circuit under varying feed ore conditions, focusing on both uncontrollable parameters (such as ore hardness) and controllable parameters (including circuit layout and pebble crusher configurations). The study is carried out with Simulink dynamic simulations. Our findings reveal several key insights. Firstly, plant designs based solely on static simulations may not be adequate for large or complex circuits, as they fail to account for the dynamic nature of milling processes. Second, incorporating stockpiles after pebble crushing can effectively mitigate the impact of dynamic fluctuations, leading to more stable circuit performance. Third, different circuit layouts can facilitate easier maintenance and operational flexibility. Notably, finer pebble crushing can enhance circuit throughput by 5% to 10%. [ABSTRACT FROM AUTHOR]

Background and Objectives: When a haematopoietic stem cell registry size is constrained by limits on recruiting, as in Canada, identifying the right person to recruit is a critical determinant of effectiveness. The aim of this study was to evaluate the impact of changes to donor recruitment effort, within ethnic groups, on the matching effectiveness of the Canadian registry as it evolves over time. Materials and Methods: Simulation methods are applied to create a cohort of donor recruits and patients over a 10‐year time horizon. New recruits are added to the registry each year, while some existing donors 'age‐out' upon reaching their 36th birthday. In a similar fashion, simulated patient lists are created. At the end of each simulated year, simulated patients are matched against the simulated registry. Results: There are increased matches in non‐White populations when diverse registrants are preferentially recruited, but there are larger decreases in the number of matches for Caucasian patients. Additionally, ethnic communities that have limited registrants in the Canadian registry in 2021 do not benefit from increased recruiting efforts as much as communities with a larger initial number of registrants. Conclusion: Preferentially recruiting from non‐Caucasian populations reduces the number of matches from Canadian sources because increases in non‐Caucasian populations will not fully counterbalance decreases to Caucasian patient matches. Nevertheless, more than 80% of all matches are for Caucasian patients, regardless of the donor recruiting effort within ethnic groups. [ABSTRACT FROM AUTHOR]

The presented article deals with the issue of inventory management optimization through modelling and simulation in the software Tecnomatix Plant Simulation. Based on an in-depth analysis of the supply chain with an emphasis on inventory management, a simulation model was developed. It was optimized using the inventory theory methodology in combination with a discrete-event simulation approach. Dynamic simulation made it possible to perform experiments and optimize the existing state. The solution to the problem is elaborated on a case study to achieve the efficiency of the supply process of a specific operation of a clothing retail chain, which is struggling with the problems of excessive and inaccurate supply. [ABSTRACT FROM AUTHOR]

Realistic simulation of dynamic interaction between plants and different natural environmental factors is a key topic in the field of natural landscape simulation. At present, few researches focus on the accumulation of snow on plants and the simulation of the dynamic deformation of a branch under the influence of the accumulation of snow. Therefore, we propose a simulation method for the dynamic interaction between snowfall and plants based on physical models. We first analyze the structure of the target plant and establish its physical structure model. Then we use the particle system and the plant branch collision detection method to calculate the amount of snow accumulation on the branches and generate the fluctuating snow grid surface based on the Berlin noise function. Finally, the cantilever beam model is used to calculate the deformation of branches under snow pressure. This modeling method proposed in this paper can provide a new research idea and technical reference for simulating the dynamic interaction between plants and environmental factors represented by snow. [ABSTRACT FROM AUTHOR]

Backgrounds: In this paper, a kind of mining MR damper with shear and valve working mode is designed. Compared with the traditional damper, this MR damper has better energy dissipation characteristics and can provide greater damping force in a short time. Its damping can be adjusted with the excitation current. Purposes: The aim of the present paper is to analyze and study the performance of this novel mining MR damper and test the working performance and feasibility of this MR damper. Methods: Optimizing and establishing a Simulink dynamic simulation model based on Bingham model and testing the performance parameters of the MR damper. The vibration mitigation experiment of mining vibrating screen based on spring damper is designed. Results: This paper compares the experimental and simulation results and found that the error of the maximum damping force shall not exceed 3%.Compared with traditional metal spring and ROSTA spring, the MR damper can reduce the downtime of the vibrating screen by more than 80%. Conclusions: From the results, the present paper provides theoretical basis for the performance test of the damper. The excitation current is the main factor affecting the maximum damping force of the MR damper. The correlation between the excitation current and the maximum damping force is more than 90%. MR damper can not only effectively avoid the resonance of the vibrating screen, but also will not affect the stable amplitude of the vibrating screen when it works, and can also greatly reduce the downtime of the vibrating screen. [ABSTRACT FROM AUTHOR]

Educational buildings are public buildings where highly dense pedestrian traffic is seen during the daytime. Although stairs are mainly used in vertical circulation, the presence of an elevator is also required by the regulations. However, when the relevant standards and regulations are observed, a comprehensive analysis method or agenda procedure detailed to determine the number and capacity of the elevator/s for the education building has not been noticed. With the research, elevator design, which is an important design problem, is examined in terms of elevator traffic analysis according to the literature review findings and is also hypothetically evaluated through the schools listed in the building catalog of the Ministry of National Education (MNE). According to both the traditional -based on mathematical calculations- and the modern method -with the help of dynamic simulation program-, elevator traffic analyzes are carried out based on different user profiles, and the carrying capacity of the elevators are tested in the buildings selected. The results of the analysis are evaluated in terms of the Average Waiting Time (AWT), which is considered important for elevator traffic, so that the limits of the system/s are determined. Based on the traffic analysis results of the hypothetical scenarios examined within the scope of the study; it has been observed that the minimum requirements in the legislation/s are determined only by considering the use of elevators due to disabled users, while the possibility of using elevators of the others is not evaluated. It is noticed that the number of elevators prescribed in the regulations for educational buildings and their capacities are examined with disabled users in mind. There was no evidence that a detailed elevator traffic analysis of all users was conducted. [ABSTRACT FROM AUTHOR]

The aim of the work was to develop a multi-body model that can simulate the Impact between the vehicle wheel and a pothole. The model consists of the vehicle wheel together with front McPherson suspension assembly and a potholed road surface. Therefore the kinematics of the suspension when the vehicle hits a pothole can be simulated. The model was first predetermined by an analytical calculation and then successfully validated by an experimental test performed with the same parameters as the virtual model. The results were very similar and therefore allow the model to be used to simulate different scenarios in terms of wheel dynamics and behavior when impacting potholes with different depths. [ABSTRACT FROM AUTHOR]

Understanding of the human body's internal processes to maintain balance is fundamental to simulate postural control behaviour. The body uses multiple sensory systems' information to obtain a reliable estimate about the current body state. This information is used to control the reactive behaviour to maintain balance. To predict a certain motion behaviour with knowledge of the muscle forces, forward dynamic simulations of biomechanical human models can be utilized. We aim to use predictive postural control simulations to give therapy recommendations to patients suffering from postural disorders in the future. It is important to know which types of modelling approaches already exist to apply such predictive forward dynamic simulations. Current literature provides different models that aim to simulate human postural control. We conducted a systematic literature research to identify the different approaches of postural control models. The different approaches are discussed regarding their applied biomechanical models, sensory representation, sensory integration, and control methods in standing and gait simulations. We searched on Scopus, Web of Science and PubMed using a search string, scanned 1253 records, and found 102 studies to be eligible for inclusion. The included studies use different ways for sensory representation and integration, although underlying neural processes still remain unclear. We found that for postural control optimal control methods like linear quadratic regulators and model predictive control methods are used less, when models' level of details is increasing, and nonlinearities become more important. Considering musculoskeletal models, reflex-based and PD controllers are mainly applied and show promising results, as they aim to create human-like motion behaviour considering physiological processes. [ABSTRACT FROM AUTHOR]

Coastal aquaculture is an important economic activity in India dominated majorly by shrimp culture, which involves a range of interconnected processes that are challenging to analyse and optimise without a systematic approach. System dynamics modelling is a useful tool for understanding and predicting the behavior of complex coastal aquaculture systems. here, we review the status of dynamic simulation modelling works undertaken in aquaculture, which can provide directives for various researchers working on developing simulation models for shrimp aquaculture. There is a need to assess the impact of dynamic forces on the animals during the culture period which could be addressed through these models. System dynamic models assist decision-makers to augment potential measures for aquaculture-related problems under different possible scenarios. System dynamic models developed in aquaculture were related to feeding, water quality parameters, nitrogen dynamics, growth, etc. The strengths and limitations of software packages used in developing the simulation models are discussed. Considering the economic potential of shrimp aquaculture, it is important to develop an integrated dynamic model for predicting all the sub-processes of shrimp aquaculture. [ABSTRACT FROM AUTHOR]

Copyright of Revista: Módulo Arquitectura CUC is the property of Corporacion Universidad de la Costa, CUC 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.)

• Conversion of a DHN to diversified and decentralized renewable supply. • Fully physical digital twin of real DHN used to compare five renewable scenarios. • Implementation of up to 11 different generation and storage technologies at once. • Thermal energy storages with high charging/discharging power are essential. • Results show that at least 98 % renewable supply is possible. Due to the tremendous effects of climate change, the goal of a climate-friendly energy supply has developed into the main task of the energy sector. Today climate neutrality is a central issue at social, political and economic levels. It is a sector coupling issue, requiring renewable energies in electricity, mobility and heat supply. While the heat sector contributes the largest share to final energy demand of German municipalities, it is also the sector for which the path towards climate neutrality will be most challenging. This study presents pathways for large cities for the transition from fossil to renewable heat supply based on the example of Rostock. A detailed, fully-physical simulation model for Rostock's district heating was developed considering different potential heat sources including heat pumps, industrial and process heat, incineration of sewage sludge, waste and solid biomass as well as geothermal and solar thermal plants. Additionally, thermal energy storages have been integrated into the model. The study highlights the importance of simulation models in evaluating the feasibility of energy systems and emphasizes the need for incorporating detailed information in these models to obtain accurate results. Multiple scenarios have been investigated in order to analyse the interplay of heat generation, storage and the annual course of heat consumption. Five final concepts were derived meeting the requirement of climate-neutral heat supply. Although the results show that each variant has advantages and disadvantages, heat generators that make technical and economic sense in all cases were identified. The implementation of these is recommended. [ABSTRACT FROM AUTHOR]

Background Breast reconstruction (BR) using autologous free flaps has been shown to have numerous psychosocial and quality-of-life benefits. Unfortunately, the microsurgical learning curve is quite steep due to some unique operative challenges. Currently, there is no realistic simulation model that captures real-life respiratory excursion and the depth of internal mammary vessels within the compact recipient site. The purpose of this study was to delineate intraoperative measurements of depth and motion, describe the resulting simulation model, and conduct a pilot study evaluating the simulator as an educational resource. Methods This is a single-center, ethics-approved study. For the intraoperative measurements, all consecutive patients undergoing free flap BR using internal mammary vessels as recipients were recruited. Patient and intraoperative factors as well as intraoperative measurements were recorded. A dynamic model was developed based on intraoperative parameters. For the pilot study, plastic and reconstructive surgery trainees were recruited to complete a hand-sewn internal mammary artery (IMA) anastomosis using the new simulator and completed objective questionnaires pre- and postsimulation. Subjective feedback was recorded and themes determined. Results Fifteen operative sites were analyzed. Flap pocket was found to be between 4 and 5 cm in depth with vertical excursion of 3.7 ± 1.0mm and a respiratory rate of 9 to 14 breaths/minute. Previous radiation, rib space, body mass index (BMI), blood pressure, heart rate, tidal volume, and respiratory rate showed no correlation to vessel depth/excursion. Laterality, rib space, BMI, radiation, vitals, and tidal volume had no correlation with vessel movement. Twenty-two trainees were included in the pilot. An increase in confidence and mixed results for anxiety was reported. Conclusion This study reports a novel microsurgical simulation model that provides a realistic deep inferior epigastric perforator free flap BR IMA anastomosis experience. It replicates movement of vessels in situ with real-time respiratory excursion and similar physical structures of the internal mammary system. This model shows promising results for increased use in microsurgical education. [ABSTRACT FROM AUTHOR]

Ductwork components in ventilation systems are often installed in close proximity to each other due to space constraints. Published pressure loss coefficients are, however, only valid if there are sufficient distances between components. In this work, pressure losses of common combinations of two, three, and four bends and the addition of internal vanes were investigated with computational fluid dynamic simulations and validated with reference data. Pressure losses of combinations of bends without vanes were higher or lower than the sum of the single pressure losses of the components (combination effect), depending on the components and orientation. For bends with abrupt deflections, strong combination effects occurred; in some cases, pressure losses doubled. The spacing between the components was also a relevant factor. Combination effects were most pronounced for spacing lengths of the same order as the length of the flow separation region of the upstream bends. Consequently, certain spacer lengths were particularly unfavorable. Combination effects were found to be complex to predict and fluid simulations proved to be useful for analyzing the interactions. Adding vanes was found to be very useful. For bends and combinations with sharp deflections, the pressure loss coefficients were reduced by a factor of ten with vanes. Vanes also effectively reduced detrimental combination effects. The combination pressure losses with vanes were in all cases lower than the sum of the single components pressure losses. Pressure loss coefficients for combinations with vanes had a strong dependency on the Reynolds number. Furthermore, the downstream flow distributions were more homogeneous with vanes. [ABSTRACT FROM AUTHOR]

The efficiency of the assembly process is influenced by a wide range of different parameters. For their optimal setting, a thorough comprehensive analysis of the entire assembly process and identification of shortcomings in the form of bottlenecks or insufficient capacity utilization of assembly workplaces is necessary. As part of the presented paper, the use of the FMEA method in combination with dynamic simulation for analysis of the efficiency of its operation is presented on the example of a real assembly process. The obtained results showed the existence of a bottleneck in the supply area carried out by means of a single AGV set. The subsequent proposed solution, which consisted in the introduction of the use of another AGV set, brought an increase in the efficiency of individual assembly workplaces from the original values in the range of 75% to 85% to the level of 87% to 98%. [ABSTRACT FROM AUTHOR]

The startup process is the crucial transition phase of the supercritical carbon-dioxide Brayton cycle, so it is essential to focus on and investigate the transient performance for the system's safety and stability. The pressure in the buffer tank approaches the safety upper limit with different startup schemes during the joint commissioning of the compressor and heater in a MWe-scale experiment system, while the maximum temperature is 309 °C. Hence, dynamic simulations are carried out to explore the dynamic startup characteristics from a cold state or a warm state to the turbine pre-start condition, in which 60% of the rated mass flow rate and 67% of the rated compressor speed are reached in the end. The results show that, when starting from a cold state, the startup scheme of simultaneously heating and speeding up has a limited effective application scope. Two venting operations during the above process help the system establish heat regeneration and promote temperature uniformity in the system. Furthermore, when starting from a warm state with an existing temperature gradient in the system, the startup scheme of simultaneously heating and speeding up is more effective and has a more extensive range of control. [ABSTRACT FROM AUTHOR]

Dynamic behavior of agricultural implements has always been a challenging topic for researchers. In precision farming, precise control of the agricultural implements is a very important task. To study the dynamics of agricultural implements, Researchers conduct field experiments as well as laboratory tests. These methods are very costly and the measurements are usually associated with some errors. Providing well-controlled experimental conditions in practice is very difficult, if not impossible. In this article, the capability of the SolidWorks in simulation and predicting the dynamic behavior of a conventional sprayer boom is discussed. To validate the results, field tests were conducted using a conventional sprayer boom. The results showed that there was no significant difference at 95% confidence level between results from computer simulation and those obtained from the field test of conventional sprayer boom. [ABSTRACT FROM AUTHOR]

Since existing energy system models often represent storage behavior in a simplified way, in this work, a tool chain for deriving consistent storage model parameters for optimization models is developed. The aim of our research work is to identify what are non-negligible influences on the the technical characteristics and dynamic behavior of the storage, to quantify the effect of these influences, and represent these effects in the model. This paper describes the developed tool chain and presents its application using an example. The tool chain consists of the steps "parameter screening", "dynamic simulation", "regression analysis" and "refining optimization model". It is investigated which parameters have an influence on the storage system (here pumped hydroelectric energy storage (PHES)), how the storage behavior is modeled, which influencing factors have a measurable effect on the system, and how these findings can be integrated into optimization models. The main finding is that in the case of PHES, the dependency of the charging and discharging efficiency on the power is significant, but no further influencing factor has to be considered for accurate modeling (0.946 ≤ R2 ≤ 0.988) of the efficiency. It is concluded that the presented toolchain is suitable for other storage technologies as well, including the analysis of aging behavior. [ABSTRACT FROM AUTHOR]

Learning about human eye movements broadens our comprehension of the visuomotor system and aids in the effective management of strabismus. One's clinical practice is improved by a dynamic simulation of human eye movements using physical models of the extraocular muscles (EOMs). We use our eyeball model to teach the basics of strabismus to undergraduate students and ophthalmology residents. In Listing's plane, extraocular movements of each muscle and the angle demonstration are being used to familiarize students with their knowledge. The degree of the residents' understanding of strabismus is significantly influenced by the eyeball strabismus simulator. This model is an inexpensive, Do It Yourself (DIY) model that is simple to build. [ABSTRACT FROM AUTHOR]

The spring finger collection mechanism is a core component of balers. It is usually used to collect soft straw crops (corn straw, wheat straw, green forage), and rarely used for hard stem crops (such as branch pruning residues). Due to different biophysical characteristics of hard stem crops and soft straw crops, the collection mechanisms are also different. In China, branch pruning residues in apple orchards are collected manually. It is a heavy labor task. To this end, this article uses an improved spring finger mechanism to collect pruning residues in apple orchard branches, effectively replacing manual collection operations. A dynamic motion trajectory simulation platform is developed by analyzing each action using pitchforks or other agricultural tools throughout the entire collection process, and combined with the structure of the spring finger collection mechanism. The platform of the spring finger collection mechanism is improved to collect orchard branches, and redesign and manufacture the core components of the collection mechanism. In addition, comparative tests were performed on4 different placement orientation sunder the conditions of R=40±2 r/min and V=0.9-1.1 m/s. That is, 1) messy, 2) transverse, 3) portrait orientation (the treetop firstly contacts the collection device), and 4) portrait orientation (the thick stems of the branches first touch the collection device). The results indicate that 1) and 2) have similar success rates in picking branches, while 3) and 4) have lower success rates, especially with 4) being the lowest). The analysis found that some branches were directly inserted into the spring finger gap and moved under the machine, resulting in a large amount of losses. This study aims to improve the success rate of picking branches in the bundling machine and verify the relationship between different placement directions and the success rate of picking branches. [ABSTRACT FROM AUTHOR]

The interest to ensure thermal comfort becomes one of the major challenges in the building sector, not only for the quality of interior ambiences, but also to minimize the energy rate consumed for heating and cooling systems. This paper presents the advantage of using the adaptive approach and numerical simulation to assess the level of thermal comfort of dwellings of different architectural typology in hot climate. For this purpose, the method is based on in situ measurements effected on two samples of traditional and contemporary typology; using anemometer instrument, where the climatic parameters measured inside and outside samples are: ambient temperature, relative humidity rate and air velocity. The simulation work is performed by Energy-Plus software; consequently experimental tests are realized on the local material in order to know their physical and thermal characteristics. The results obtained demonstrate the efficiency of the traditional passive devices, which are able to provide a comfortable thermal ambience without referring to the air conditioning system, with an operating temperature of 30.5ºC and a satisfaction rate of 80%. [ABSTRACT FROM AUTHOR]

Displaced populations are housed in various constructions, including lightweight predesigned structures. Theoretically, self-built heavyweight structures should ensure better temperatures and be closer to cultural norms. To examine this directly for the first time, lightweight pre-designed solutions are compared with high-mass self-built alternatives in Afghanistan and Peru, via monitoring, dynamic simulation, occupant surveys, the Shelter Assessment Matrix (SAM) and ShelTherm. Lightweight solutions increase peak summer temperatures, but only by 2°C, but reduce minimum temperatures by up to 5°C. Simulations only provided a qualitatively similar time series to the monitoring, because identical homes showed a large variance in temperatures. This questions the benefit of simulation compared to approaches which concentrate on whether shelters exacerbate or ameliorate external temperatures. In addition, a dwelling provides more than comfort, it supports family life, which is best addressed by tools like SAM, not thermal simulation. Hence it might be ideal to recommend high-mass self-build if possible, and to focus modelling efforts on qualitative aspects of simulation time-series, such as whether the building suppresses or exacerbates external conditions, and equally on psycho-cultural aspects. The term narrative modelling is introduced to describe this new approach which will be of direct benefit to the humanitarian community. Practical application : Building simulation engineers have much to offer the humanitarian shelter sector, however they are not often brought into play in a disaster. Hence, we suggest a practical role they can take is in examining strategies before disasters and in creating knowledge or analysis methods that aid agency staff can apply on the ground. Here we showcase this approach. It is clear that although dynamic thermal simulation is highly useful, psycho-social aspects are equally important, thus engineers are likely to need to use tools that consider such aspects in order to maximize the usefulness of their conclusions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Research & Development / Revista de Investigación & Desarrollo is the property of ECORFAN-Mexico S.C. 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.)

Copyright of Journal of East China University of Science & Technology is the property of Journal of East China University of Science & Technology 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.)

Emergency materials transportation, both economic and societal, is one of the most important parts of unconventional emergency management. In the present study, we built a quantitative simulation model underlying the mechanism of emergency materials transportation specifically regarding typhoon disasters. We then explored the internal influence factors and association mechanisms of the dynamic model as they relate to the effective control and guidance of emergency materials transportation. Using system dynamic model, this paper conducts the simulation study to identify the key influencing factors for the speed of emergency materials transportation. The relationships between influencing factors and the emergency capability were analyzed qualitatively. On this basis, SD flow chart was built. A typhoon disaster event in Leizhou Peninsula, China, is used as an example to validate the effectiveness and feasibility of the proposed model, as well as to simulate different emergency management strategies. Results of governmental emergency materials transportation are key factors in process of emergency formulating the policy to improve the speed and efficiency for emergency materials transportation during the emergency management process. [ABSTRACT FROM AUTHOR]

Aztreonam is a Gram-negative bacteria-targeting synthetic monobactam antibiotic. Human serum albumin (HSA) plays an important role in the transference of pharmaceuticals, hormones, and fatty acids, along with other compounds, determining their biodistribution and physiological fate. Using several biophysical and in silico approaches, we studied the interaction of aztreonam with HSA under physiological environments in this study. Results confirm the formation of HSA-aztreonam complex where aztreonam showed moderate affinity towards HSA. A static mode of quenching was confirmed from the steady state fluorescence data. FRET findings also showed that there was a significant feasibility of energy transfer between HSA and aztreonam. Site marker displacement experimental conclusion suggested the binding site of aztreonam was the sub-domain IB of HSA. Circular dichroic spectroscopic analysis suggested that aztreonam interaction decreases the α-helical content of HSA. Changes in microenvironment were studied through synchronous fluorescence data. According to molecular docking results, the HSA-aztreonam complex is mostly maintained by non-covalent forces, with a binding energy of 7.7 kcal mol−1. The presence of a hydrogen bond, van der Waal interaction, and pi-anion interaction in the binding process, as well as conformational changes in HSA after binding with aztreonam, are all confirmed by molecular dynamic simulation. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) 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.)

Under the current rapid urbanization and industrialization in China, competition for production, living, and ecological spaces is becoming fierce. Improving production–living–ecological spaces (PLESs) has become a core issue in China's land‐space development strategy. In this study, the multiple linear logistic regression (MLLR)–multicriteria evaluation (MCE)–cellular automata (CA)–Markov hybrid model was used to predict the land‐use pattern for 2030, and the spatial conflict model was established based on landscape indices to measure the evolution characteristics of spatial conflicts. The results demonstrated that, from 2005 to 2030, the production–ecological space (PES) will have front‐runner status in Wuhan, followed by the ecological–production space (EPS). In 2005–2015, the living–production space (LPS) and PES occupied large amounts of EPS and ecological space (ES), especially in the main urban areas and near rivers, and the spatial transformation was the most significant. By 2030, there will be less transformation of each space type, but the conversion amount of LPS will still be relatively large. With the passage of time, the LPS will increase, the EPS will decrease slightly, and the ES will fluctuate. During the period 2005–2030, the conflict level will change gradually from seriously out of control to controllable, and the hot spot of PLES will show a scattering distribution. The cold spot area will be distributed mainly in the southern part of Wuhan, which will be expanded greatly by 2030. Our research indicates that analyzing the reasonable utilization of PLES is of great value by identifying spatial conflicts; differentiated sustainable development strategies should be formulated according to the future spatial and temporal patterns of PLES, which can help in scientific judgments on the spatial matching of land use and provide early warnings of spatial conflicts. Integr Environ Assess Manag 2022;18:1578–1596. © 2021 SETAC KEY POINTS: The exchange of production–living–ecological spaces can present the contradictory signals of regional spatial conflict.The results of conflict identification of PLES in time and space can provide a reference for future regional specific optimizing land allocation.The measurement model constructed based on the landscape pattern indices can reveal the identification of regional spatial conflicts. Over time, the PLES spatial conflict in Wuhan will be gradually improved. [ABSTRACT FROM AUTHOR]

The aim of this paper is to develop a generalized MATLAB program to study the dynamic behavior of a threephase induction motor. The d-q axis transformation theory is applied in rotor reference frame to study the motor dynamics. A general-purpose MATLAB program is developed and used for the dynamic simulation of a 5HP, 460V, 60Hz, 4-poles induction motor. The developed program is used to study the effect of variation of Stator Resistance (Rs), Moment of Inertia (J), and Load Torque (TL) at t=0.7sec during transient state. The results obtained show that, the torque-speed characteristic curve and mechanical rotor speed-time characteristics of induction motor depend upon the rotor resistance and the moment of inertia. Also, during the simulation of the motor under loaded torque at t=0.7sec, the results showed an increase in the initial starting torque and it reduces from 2000Nm - 0Nm as the operating time progressed. A sudden residual increase occurred in the torque from 0-1000Nm at the loaded time t=0.7sec, and the mechanical rotor speed increased at starting time from 0-1800rpm with respect to operating time and suddenly experienced a drop from 1800rpm to about 1700rpm at the loaded time of t=0.7 sec. The developed program is particularly useful for machine designers in the manufacture of various types of induction machines. [ABSTRACT FROM AUTHOR]

In order to increase the efficiency of the order-picking process, warehouses are forced to find ways to adopt to constantly intensifying changes in the assortment and quantities of stored products. Accordingly, we present a methodology that deals with such a problem at a tactical level by defining the optimal size and an allocation of products within the order-picking area of the most typical order-picking setting. The methodology combined two methods, dynamic programming and simulation modelling, with the aim of taking advantages of their positive features. In that sense, the optimal allocation of products for different sizes of the order-picking zone were obtained by the dynamic programming approach. Afterwards, the influence of a demand's seasonality and variations were treated by the simulation model, so that the more realistic performances of the system were captured for the optimal allocation of products. The methodology was tested on the retailer data with significant week seasonality. The obtained results confirmed the practical applicability of the methodology in real systems, while the sensitivity analysis of results showed that special attention and effort should be given to the determination of costs related to the engagement of order-pikers, storage equipment and unit replenishment during a planning period. [ABSTRACT FROM AUTHOR]

Angiotensin converting enzyme (ACE) is a key enzyme and mediator in the aetiology of high blood pressure (HBP) and hypertension. As one of the leading cause of untimely death worldwide, there is a lot of research and studies on the management and treatment of hypertension. The usage of medicinal plants in the management of hypertension as alternative to synthetic allopathic drugs is a common practice in folkloric and traditional medicine. Therefore, this study was aimed to investigate the ACE inhibitory activity of some medicinal plants which are commonly used in the treatment of HBP in southwestern part of Nigeria using extensive in-silico approach. Compounds identified in the plants through GC–MS technique, together with Lisinopril were docked against ACE protein. It was observed that only 40 of the compounds had binding affinity ≥ − 6.8 kcal/mol which was demonstrated by the standard drug (lisinopril). Interaction between the compounds and ACE was via conventional hydrogen, carbon hydrogen, alkyl, pi-alkyl, pi-carbon, and Van Der Wall bonds among others. Most of these compounds exhibited drug like properties, without violating majority of the physicochemical descriptors and Lipinski rule of 5. The ADMET evaluation revealed that only 2 compounds (cyclopentadecanone and oxacycloheptadecan-2-one) which were identified in Bacopa florinbunda plant were predicted non-toxic and thus were subjected to molecular dynamics and simulation with ACE. From the molecular dynamics and mechanics analysis, both cyclopentadecanone and oxacycloheptadecan-2-one showed high stability and inhibitory potentials when bound to ACE. Oxacycloheptadecan-2-one was more stable than lisinopril and cyclopentadecanone in the ligand–ACE complex; we therefore suggested its experimental and clinical validation as drug candidates for the treatment of hypertension. [ABSTRACT FROM AUTHOR]

The main objective of this work is to develop a new workflow integrating numerical simulations of fluid flow and dynamic rupture propagation, machine learning regression techniques and Bayesian inversions of subsurface model parameters. We present the theory behind each step as well as practical application of the proposed methodology on the May 2012, Mw4.8 Timpson, TX, earthquake. Numerical simulations show that the triggering of the earthquake is related to the wastewater disposal with the dominant role of poroelastic stress changes. Dynamic rupture simulations allow us to reproduce the size of the earthquake. Using the results from a set of simulations, we form a training dataset and compare the performance of different regression algorithms. Random Forest, Bagging and K-Neighbors regression algorithms are the most promising and we use them in the inversion procedure to replace numerical simulations. We test multiple inversion scenarios and cross-validate them with the results of numerical simulations to constrain stress state and fault frictional parameters by matching the observations (the moment magnitude of the real event). We also discuss the limitations of the current methodology and propose further extensions in the future. [ABSTRACT FROM AUTHOR]

The paper proposes a sliding mesh model-based method to conduct a dynamic painting simulation for an arc connecting surface. In order to meet the requirements for using a sliding mesh model, the computational domain was designed with three parts—a stationary part, a translational part and a rotational part. The film-forming model based on the Euler–Euler model and the conservation equation for a sliding mesh model were established. The dynamic painting of arc connecting surface with the angles of 60, 90 and 120 degrees under the nozzle speed of 100 mm/s were simulated. It was found that the thickness on the arc surface section was larger than those on the plane sections, and through an analysis of the vector distribution, the reason for this was that more paint would be deposited on the arc surface section than on the plane sections due to the concavity of the arc surface. The results obtained from the simulation were in a reasonable agreement with the experimental results, which indicates the proposed method would be effective and applicable in simulating a dynamic painting process. [ABSTRACT FROM AUTHOR]

The use of temperature rise inhibitors (TRIs) holds significant promise in mitigating thermal cracking issues in modern concrete by controlling the precipitation of C-S-H gel, the main product of cement hydration. However, the complexity of their interaction with the non-classical nucleation process of C-S-H remains unclear. This study systematically investigated the influence of a sorbitol-based liquid-type temperature rise inhibitor (L-TRI) on the hydration kinetics of cement suspension using a combination of methods, including conductivity testing, pore solution analysis, and molecular dynamic simulations. It is revealed that the admixture-to-water ratio, rather than admixture-to-cement ratio, governs the effect of L-TRI on cement hydration. The disturbance of L-TRI molecules in the pore solution, mainly calcium complexation and water stabilization, plays a decisive role in inhibiting the secondary nucleation of C-S-H and decelerating the following growth. In contrast, L-TRI has a negligible influence on cement dissolution and the formation of C-S-H precursor. • Non-adsorbed L-TRI polymer impacts cement hydration through pore solution disturbance. • L-TRI barely affects cement dissolution and primary nucleation of C-S-H. • L-TRI inhibits the secondary nucleation of C-S-H by calcium complexation. • L-TRI decelerates the growth of C-S-H by calcium complexation and water stabilization. [ABSTRACT FROM AUTHOR]

Layer-by-layer self-assembly of polyelectrolytes is one of the most promising methods for preparing nanofiltration membranes. Here poly (sodium 4-styrenesulfonate) (PSS) and poly (diallyldim-ethylammonium chloride) (PDADMAC) were chosen to prepare polyelectrolyte multilayer (PEM) membrane. The effects of background salt concentration, PSS concentration, background salt types, the number of layers and the outermost functional groups on the separation performance of the PEM were investigated systematically. Molecular dynamic simulation was employed to simulate the influence of background salt on the diffusion of PDADMAC. The simulation results agree well with the experimental results. The optimized (PSS/PDADMAC) 4.5 membrane with Na 2 SO 4 as background salt shows permeance of 15.9 LMH/bar, Na 2 SO 4 rejection of 98.2 %, and an excellent stability. Our study provides both theoretical and experimental supports for the preparation of PEM membranes using LBL method. [Display omitted] • Affecting factors were systematically investigated for polyelectrolyte membrane prepared by layer-by-layer self-assembly. • MD simulation results show that different ions influence the diffusion rate of polyelectrolyte. • The obtained membrane shows excellent separation performance for corresponding salts. [ABSTRACT FROM AUTHOR]

Knowledge about factors affecting the dynamic response process is crucial for development of mixed-potential gas sensor for various applications such as hydrogen detection. Based on a double layer capacitor model and the Butler-Volmer equation, the present work studied the dynamic hydrogen sensing process by numerical simulation in combination with experimental assessment. Simulation shows that both response and recovery times are jointly determined by the decrease rate of the net reaction current and the magnitude of response. Increase of standard reaction rate constants, transfer coefficients, standard equilibrium potential, or gas concentrations accelerates both the response and recovery processes, while double layer capacitance has a reverse effect. A power-law concentration dependence of the response/recovery time is obtained under Tafel kinetics. The simulated response curves and behavior agree quite well with the experimental results. These findings shed lights on the sensing kinetics of the mixed-potential hydrogen sensor, and may help guide the sensor design. • Theoretical and experimental study of dynamic mixed-potential gas sensing process. • Factors function via tuning decrease rate of net reaction current and response value. • Materials of high electrochemical activities favor the sensing dynamics. • Power-law concentration dependence of response time under Tafel kinetics. [ABSTRACT FROM AUTHOR]

The present work shows the design of two simulations using free dynamic software that allows efficient modeling of the reflection, refraction and polarization of light. Specifically, the objective of the designed simulations is to verify computationally the laws of Snell and Malus, evaluating each one of the phenomena in an ideal way. These simulations were developed in GeoGebra computer software which allows the generation of dynamic designs referring to the nature and propagation of light. As a result, the numerical verification of each of the physical phenomena under study is shown, thus generating validity and reliability in the design of the simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] Large-scale freezing and thawing experiments of monoclonal antibody (mAb) solutions are time and material consuming. Computational Fluid Dynamic (CFD) modeling of temperature, solute composition as well as the stress time, defined as the time between start of freezing and reaching T g ' at any point in the container, could be a promising approach to ease and speed up process development. Temperature profiles at six positions were recorded during freezing and thawing of a 2 L rectangular bottle and compared to CFD simulations via OpenFOAM. Furthermore, cryoconcentration upon freezing and concentration gradients upon thawing of a mAb solution were predicted and the stress time calculated. Temperature profiles during freezing were accurately matched by the CFD simulation. Thawing time was only 45 min to 60 min longer in the model. The macroscopic cryoconcentration of the mAb was also matched by the simulation; only a highly concentrated region in the top and a diluted core in the geometrical centre of the 2 L bottle were not well reflected in the simulation. The concentration gradient after thawing obtained by simulation as well agreed with the experimental result. In addition, CFD simulations allowed to extract the global temperature distribution, the formation of ice, and thus the distribution of stress in the freezing liquid. CFD simulations via OpenFOAM are a promising tool to describe large-scale freezing and thawing of mAb solutions and can help to generate a deeper understanding and to improve testing of the robustness of the processes. [ABSTRACT FROM AUTHOR]

Corrective osteotomy of malunion of both forearm bones is a challenging procedure because it needs accurate angular and rotational correction of both bones. Recent advances in three-dimensional (3D) printing techniques have shown promising results in the correction of complex deformities. We report a patient with malunion of both bones of the forearm in whom we determined site and degree of correction required based on the computed tomography images of the affected side and mirrored images of the contralateral healthy side. We then created 3D printed sawbones and simulated osteotomy to confirm stable dynamic forearm rotation. This method enabled satisfactory restoration of anatomical and functional outcomes. Preoperative dynamic motion simulation using 3D printed anatomic bone model is helpful for complex corrective osteotomy of forearm fracture malunion. Level of Evidence: Level V (Therapeutic) [ABSTRACT FROM AUTHOR]

SDTrimSP is a popular simulation program to compute several effects of the interaction between an impinging ion and a solid, such as ion implantation ranges, damage formation or sputtering of surface atoms. We now introduce a graphical user interface for SDTrimSP to make its operation more accessible for a broad group of users. It is written as a separate Python program and is not restricted to any specific operating system. The interface allows a quick and easy start as well as the direct evaluation of SDTrimSP simulations. Its capabilities are demonstrated here in the form of several example cases, including the dynamic simulations with SDTrimSP, where ion-induced target changes are taken into account. The presented graphical user interface is made freely available to support a large number of users in performing simulations of ion–solid interaction. [ABSTRACT FROM AUTHOR]

Ecuador is a country with several climate zones. The zones' characteristics are very different; however, there are social housing prototypes used in all the territories. This study constitutes the second part of the analysis of a social housing prototype in four zones (Cfb, Af, Aw, and BSh) in both the current climate situation (2020) and its projection to 2050. Improvement measures from the original dwelling block have been proposed according to the initial diagnosis, considering seven passive performance variants. A total of 56 dynamic simulations have been performed for both the current and 2050 climate scenario. The results have shown that, depending on the climate zone, improvement measures differently influence comfort ranges. In addition, the behaviour of the dwellings on the upper floor is different from those on the ground floor. This study is a starting point to show that prototype solutions of social housing should be adapted with various improvement measures and should be based on specific requirements according to their location to achieve acceptable comfort levels. [ABSTRACT FROM AUTHOR]

The ergonomics on body pressure distribution of latex product design is the future trend in bedding product design. The numerical simulation of latex pillow compression performance is critical for the optimal design of bedding products. This paper reports the use of the finite element method to simulate the compression performance of latex foam and the design of latex pillows based on the pressure distribution and displacement changes of the human pillow system. The compression performance, shear performance and tensile performance of the latex foam are tested, and the stress and strain images of three mechanical experiments are obtained. Combined with the experimental results, three methods of 'hyper foam test data, hyper foam model parameter method and low-density foam method' were used to perform uniaxial compression simulation on bedding latex foam using the finite element software ABAQUS. The simulation results and experimental values were fitted and analyzed. The analysis found that the low-density foam simulation method has the largest R2, which is 0.9871, and the simulation result is the most accurate. The optimal simulation method was selected to simulate the dynamic pressure changes and cervical displacement of the human head and latex pillow models, as well as the simulation experiments with latex pillows of different heights. The curve is fitted to obtain the second-order polynomial equations of pressure and cervical socket displacement. In contrast, it can be concluded that latex pillow products with a neck height of 100 mm are better for the supine position of younger adult women in China. [ABSTRACT FROM AUTHOR]

Background and Objectives: The aim of this study was to show with three-dimensional simulations how the diagnostic supine roll test (SRT) is affected by the initial position of the debris within the horizontal canal (hc) and study the nystagmus patterns on changing the sequence of testing and its impact on the diagnosis of the side of involvement in hc-BPPV. Methods: A 3D dynamic simulation model was developed and applied based on reconstructed MRI images and fluid dynamics. Each semicircular canal was linked to the respective extraocular muscles to visualize nystagmus generated on stimulation of the canal. Results: The simulations of hc-canalithiasis showed that the nystagmus pattern seen with the SRT is changed by the initial position of the otolith debris within the canal and the sequence of testing. The debris changes position during SRT so that sequential steps do not start at the initial position as previously assumed. The sequence of performing the SRT steps from the right or left side influences the nystagmus pattern generated: bilateral direction-changing, bilateral direction-fixed, and unilateral nystagmus can be seen in different test conditions. The SRT itself may even reposition the debris out of the canal. Conclusions and Clinical Implications: Simulations provide a dynamic tool to study the diagnostic SRT in hc-canalithiasis. Starting the SRT from right or left has a major impact on the test outcome (unlike the Dix-Hallpike maneuver). The findings provide a new interpretation for the results of the SRT. The simulations explain the phenomenon of direction-fixed nystagmus as a logical consequence of starting the SRT with the head turned toward the non-affected side in hc-canalithiasis with debris in the ampullary arm. They also show that unilateral nystagmus seen on SRT indicates canalithiasis of the non-ampullary arm of the side opposite to the side of nystagmus. The generation of bilateral direction-changing, bilateral direction-fixed, and unilateral nystagmus can be the cause of misdiagnoses in terms of the affected side and underlying mechanisms. Finally, a recommendation for a standardized protocol for the sequence of positional tests should be established to ensure uniform interpretation of test results. [ABSTRACT FROM AUTHOR]

With the development of photovoltaic industry, the demand for silicon materials increases, and the competition in monocrystalline silicon manufacturing is becoming increasingly fierce. To improve efficiency and reduce cost, single crystal furnace operating under a driving system with high stability and reliability is of importance. This paper aims to design and optimize the driving system of the single crystal furnace. The driving system of NVT-HG2000-V1 silicon single crystal growth furnace was taken as the research object. The virtual assembly with SolidWorks 3D modeling was realized, and its dynamic simulation model with ADAMS was established. Then the motion process of the driving system was simulated. Using single variable method, the influence of the fit clearance between copper sleeve and lifting shaft as well as the screw parameters on the driving force and torque was quantitatively analyzed. The results show that when the fit clearance between copper sleeve and lifting shaft reaches 0. 071 mm, the driving torque required for the operation of the driving system can effectively reduces. The increase of lead screw inclination, thread pitch and friction coefficient between threads will lead to a significant increase in the torque required for the operation of the driving system. Reasonable technical suggestions have been proposed based on the research. [ABSTRACT FROM AUTHOR]

Due to the rapid depletion of water resources, more interest is paid for the efficient desalination process in recent years. MoS2 membrane aroused attention due to its high mechanical stability and electronic properties, which can sustain extra-large strains. In this study, the electronic properties and water desalination performance of TiO2/MoS2-hexagonal, and TiO2/MoS2-rhombohedral nanocomposites bilayer membranes were studied and simulated for the first time. The effect of TiO2 in the performance of MoS2 was observed in water desalination under the defined applied pressure ranging from 50 to 250 MPa with a 6.4 Å pore diameter. The membrane structure is created and optimized. The energy minimized for TiO2 from − 19,596.4282 kcal/mol for the initial structure to − 19,605.1611 kcal/mol for the final structure. For TiO2/MoS2-hexagonal, the energy minimized from − 4955.54271 eV) to − 4955.62091 eV and TiO2/MoS2-rhombohedral from − 6042.26925 eV to − 6046.91835 eV. A molecular dynamic (MD) simulation was performed using Material Studio 2019 to study the electronic properties under 0–1 eV electric field using the CASTEP code. The results showed a better photocatalytic performance under the external electric field. The effect of external electric field significantly intensifies absorption in the visible range and achieved a high photocatalytic activity on TiO2/MoS2. TiO2, TiO2/MoS2-hexagonal and TiO2/MoS2-rhombohedral nanocomposites bilayer membranes are simulated and evaluated for the water desalination using ReaxFF software. Both MoS2 phases with TiO2 have achieved a high salt rejection up to 97% (P-value = 0.0036, R2 = 0.958), while TiO2/MoS2-rhombohedral achieved the highest permeability (6.0*10−8 mm g cm−2 s−1 bar−1) (P-value = 0.000296, R2 = 0.972) under 250 MPa applied pressure. [ABSTRACT FROM AUTHOR]

Increasing competition and globalization that encompasses all dealings in the world of business compel SMEs to seek more successful organizational and management modes and approaches. This paper presents a simulation model for the application of Lean methods and tools in SMEs and their impact on the improvement of production processes and product sustainability. The Lean concept can be used to achieve more efficient production whilst manufacturing lower-cost products including shorter manufacturing cycle, high quality, and added value. Research results show the usefulness of the application of dynamic simulations in the detection of critical places in processes and the usefulness of the application of relevant Lean methods and Lean tools for process improvement. Simulation results underline better performance of product manufacturing through the use of Lean tools with the aim to eliminate any waste. Reengineering the assembly line focuses on the following aspects, namely reducing waste, internal logistics, redesigning workplaces, and changing the workplace layout. [ABSTRACT FROM AUTHOR]

Civil infrastructure systems transform over the long-term due to complex interactions among socio-environmental stressors, degradation of physical networks, and decision-making processes of infrastructure agencies. To incorporate such complex transformation mechanisms into infrastructure cost management, this study integrates simulation modeling and life-cycle cost analysis (LCCA) to create a framework for dynamic network-level LCCA in infrastructure systems. The proposed framework was implemented using a multi-agent simulation model in a numerical case study related to a road network affected by sea-level rise, population growth, and uncertain maintenance funding. The results include identification of several state transition, and tipping point behaviors at which small changes in service demand, maintenance budget, and adaptation investment may result in significant improvement in network cost and performance conditions. The results show the capability of the proposed framework in modeling the long-term trajectories of life-cycle costs at the network level under different stressors and decision scenarios. [ABSTRACT FROM AUTHOR]

We offer a path-centric theory of emerging technology and organizing that addresses a basic question. When does emerging technology lead to transformative change? A path-centric perspective on technology focuses on the patterns of actions afforded by technology in use. We identify performing and patterning as self-reinforcing mechanisms that shape patterns of action in the domain of emerging technology and organizing. We use a dynamic simulation to show that performing and patterning can lead to a wide range of trajectories, from lock-in to transformation, depending on how emerging technology in use influences the pattern of action. When emerging technologies afford new actions that can be flexibly recombined to generate new paths, decisive transformative effects are more likely. By themselves, new affordances are not likely to generate transformation. We illustrate this theory with examples from the practice of pharmaceutical drug discovery. The path-centric perspective offers a new way to think about generativity and the role of affordances in organizing. [ABSTRACT FROM AUTHOR]