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Smart warehouses are revolutionizing traditional logistics operations by incorporating advanced technologies such as Internet of Things, robotics, and artificial intelligence. In these complex and dynamic environments, control and operation instructions need to be transmitted through wireless networks. Therefore, wireless communication plays a crucial role in enabling efficient and reliable operations. Meanwhile, channel measurements and modeling in smart warehouse scenarios are essential for understanding and optimizing wireless communication performance. By accurately characterizing radio channels, communication systems can be better designed and deployed to meet unique challenges in smart warehouse scenarios. In this paper, we present an overview of smart warehouse scenarios and explore channel characteristics in smart warehouse scenarios. We conducted a measurement campaign for millimeter wave radio channels in smart warehouse scenarios. A vector network analyzer-based channel sounder was exploited to record channel characteristics at 28 GHz. Based on the measurements, large-scale channel parameters, including path loss, root-mean-square (RMS) delay spread, and Rician K factor were investigated. The unique channel characteristics in smart warehouse scenarios were explored. [ABSTRACT FROM AUTHOR]

This paper proposes a new metaheuristic algorithm called Particle Swarm-based picking time minimization (Pkt_PSO), ideated for picking time minimization in manual warehouses. As the name suggests, Pkt_PSO is inspired by Particle Swarm Optimization (PSO), and it is specifically designed to minimize the picking time in order case picking contexts. To assess the quality and the robustness of Pkt_PSO, it is compared to five alternative algorithms used as benchmarks. The comparisons are made in nine different scenarios obtained by changing the layout of the warehouse and the length of the picking list. The results of the analysis show that Pkt_PSO has a slower convergence rate and suffers less of early stagnation in local minima; this ensures a more extensive and accurate exploration of the solution space. In fact, the solutions provided by Pkt_PSO are always better (or at least comparable) to the ones found by the benchmarks, both in terms of quality (closeness to the overall best) and reliability (frequency with which the best solution is found). Clearly, as more solutions are explored, the computational time of Pkt_PSO is longer, but it remains compatible with the operational needs of most practical applications. [ABSTRACT FROM AUTHOR]

Panel furniture uses an intelligent management system, combined with the production method of splitting orders by process, to achieve large quantities and large-scale manufacturing, but because of the insufficient and incomplete use of technology, capacity bottlenecks still exist. The problem of rework and replenishment is a long-term problem in furniture production. Under the constraints of existing production rules, the time difference of plates rework forces the original batch of plates to wait, which reduces the efficiency of warehousing. From the perspective of intelligent manufacturing for the optimization of the plates rework process, this study, through on-site observation records and data analysis of the production system, aimed to find short-term solutions and long-term solutions. In the short-term response, the time node for the completion of the replenishment is mainly according to the process regulations, and the plates are packaged into the warehouse after the replenishment is completed in batches. The long-term response strategy is mainly to achieve the interconnection of different production systems to achieve mutual information, and the paperless online operation of the plates rework process increases the subjective initiative of each process to improve the overall efficiency of the plates rework process. [ABSTRACT FROM AUTHOR]

The fennel fruits (Foeniculum vulgare Mill. var. dulce Mill.) belong to the Apiaceae family and are processed by distillation in order to obtain an essential oil. The main component of the fennel is anethole, and for that reason the oil is used for flavouring medicinal, food and cosmetic products. The aim of the present paper is to calculate certain kinetic and thermodynamic parameters of essential oil from sweet fennel fruits, as well as to determine its antioxidant activity. Essential oils obtained from two harvest years -- 2020 and 2021, are studied. Kinetic parameters are determined at two temperatures -- 6 and 25°C. Spectrophotometer investigations were applied for 53 days at these temperatures for determining the speed constant of the oxidation process. Kinetic and thermodynamic properties of oxidation in the oil were provided using the Arhenius equation. Antioxidant potential of the essential oils was analysed as radical scavenging activity using DPPH method. [ABSTRACT FROM AUTHOR]

In the e-commerce era, efficient order fulfillment processes in distribution centers have become a key success factor. One novel technology to streamline these processes is robot-assisted order picking. In these systems, human order pickers are supported by autonomous mobile robots (AMRs), which carry bins for collecting picking orders, autonomously move through the warehouse, and wait in front of a shelf containing a requested stock keeping unit (SKU). Once a picker has approached a waiting AMR and placed the requested SKU into the respective bin, AMR and picker may separate and move toward other picking positions. In this way, pickers continuously move between different waiting AMRs without having to return to the depot. This paper treats the coordination of multiple AMRs and multiple pickers to minimize the makespan. We present a heuristic method for the deterministic case that can handle the requirements of large e-commerce fulfillment centers and successfully solves instances with more than one thousand picking positions. Based on the obtained solutions, the performance of our picking system is compared with the traditional warehouse setup without AMR support and to another work policy using fixed pairings of picker and AMR per order. We find that largely improved makespans can be expected. In addition, we analyze the effects of stochastic picking times, speed differences between AMRs and pickers, and a zoning strategy. The ripple effect caused by stochastic picking times, in which a single delay may cascade through a tightly synchronized schedule and deteriorate picking performance, can be effectively mitigated by separating the workforce into smaller subgroups. Another important finding is that pickers and AMR should have approximately the same travel speed because slower AMRs deteriorate system performance. Finally, zoning slightly decreases the flexibility of the system and should be used if dictated by organizational reasons. History: This paper has been accepted for the Transportation Science Special Issue on Emerging Topics in Transportation Science and Logistics. Supplemental Material: The online appendix is available at https://doi.org/10.1287/trsc.2023.1207. [ABSTRACT FROM AUTHOR]

In this article, I seek to contribute to the recent philosophical interest in the phenomenon of narco-culture. I build on the intervention initiated by Carlos Alberto Sánchez's A Sense of Brutality: Philosophy after Narco-Culture (2020) by articulating the spiritually "generative" aspects of violence. For this endeavor, I turn to the French philosopher René Girard, whose work audaciously understands community-building and the maintenance of social order as a violent process of sacralization. This conception of violence then permits me to challenge some of Sánchez's interpretations of the violence and brutality of narco-culture. My argument is that any comprehensive analysis of the narco-world, just as any other existential option, must consider the spiritual component that, in Girard's terms, can be expressed as a search for the sacred. [ABSTRACT FROM AUTHOR]

Background: The typology of word order in Hindi (Subject-Object-Verb, SOV) differs from that of English (Subject-Verb-Object, SVO). Bilinguals whose two languages have conflicting word order provide a unique opportunity to understand how word order affects language processing. Earlier behavioural and event-related brain potential (ERP) studies with Spanish-Basque bilinguals showed longer reading times and more errors in the comprehension of OSV sentences than SOV sentences in Basque language, indicating that non-canonical word orders (OSV) were difficult to process than canonical word order (SOV). Purpose: This study was designed to explore how the difference in word order in Hindi and English languages affects N400 parameters in proficient Hindi−English bilinguals, using semantic congruity paradigm. Methods: Twenty-five proficient Hindi−English bilingual subjects were asked to silently read the congruent and incongruent sentences presented in one word at a time in both the languages. ERPs were recorded from midline frontal, central and parietal sites. Results: The mean amplitude of the N400 effect at the parietal sites in Hindi−English proficient bilinguals was larger for English than for Hindi but there was no significant difference in the N400 latencies. Conclusion: Hindi−English bilingual subjects processed SOV and SVO sentences with equal ease as evidenced by the N400 latencies. Higher amplitude of the N400 effect with English sentences indicate that placing 'Object' as the final word makes sentences more predictable than verb as the final word. Understanding the word order difference might help to unravel the neurophysiological mechanisms of language comprehension and may offer some insights in terms of functional advantage of a particular word order in bilinguals. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias Sociales (13159518) is the property of Revista de Ciencias Sociales de la Universidad del Zulia Venezuela 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 Strategic Universe Journal / Univers Strategic is the property of Dimitrie Cantemir Christian University, Institute for Security Studies 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.)

In optimization, convex and non-convex functions play an important role. Further, there is no doubt that convexity and stochastic processes are closely related. In this study, we introduce the notion of the h − convex stochastic process for center-radius order in the setting of interval-valued functions ( I V F S ) which is novel in literature. By using these notions we establish Jensen, Ostrowski, and Hermite-Hadamard ( H. H ) types inequalities for generalized interval-valued C R − h -convex stochastic processes. Furthermore, the study provides useful examples to support its findings. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Social Sciences Research / Sosyal Bilimler Arastirmalari Dergisi is the property of ODU Journal of Social Sciences Research 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 CIRCULO de Linguistica Aplicada a la Comunicacion is the property of Universidad Complutense de Madrid 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.)

In the presented article, the initial phase is focused mainly on familiarization with the production focus of individual enterprises and their financial security, which provides a basis for the proposal of possible solutions to shortcomings. A more detailed study of production through simulation studies using Process Simulate software provides a more comprehensive view of production in the assessed enterprises, where the current course of production at workplaces is evaluated in detail, and suggestions are then offered to improve the revealed shortcomings. In the end, there is an assessment of the companies from the point of view of homogeneity, so that it is then possible to make an inter-industry comparison of the revealed errors and shortcomings, with the result of finding common recommendations for a wide industrial spectrum. [ABSTRACT FROM AUTHOR]

The effect of the location of an additional Au layer (top, intermediate, and bottom) on the residual stresses, structure, the transformation of the disordered A1 phase into the ordered L10 FePt phase, and magnetic properties of layered FePt(15 nm)-Au films on SiO2(100 nm)/Si(001) substrate is investigated. The ordering processes in the films separated from the substrates during in situ annealing are studied as well. It is shown that the level of mechanical stresses depends on the Au layer location and the number of interfaces in FePt–Au films. Both films (on the substrate and separated from it) with an intermediate Au layer had the lowest temperature of the beginning of L10 phase formation. During annealing, diffusion of Au and its redistribution along the grain boundaries of the L10 FePt phase occur. An increase in the Au concentration along the grain boundaries reduces the exchange interaction between them and increases the coercivity of the FePt/Au and Au/FePt films. [ABSTRACT FROM AUTHOR]

In response to the problem of robots needing to perform bin-picking in many industries, a small robot system was developed with a workpiece-position-detection system based on Field-Programmable Gate Array (FPGA) technology. The system integrated object detection and feature matching techniques, bolstered by optimization methods, to enhance its functionality on the FPGA platform. Furthermore, a two-wire control bus was designed specifically for reliable operation in environments characterized by strong interference, drawing inspiration from the Controller Area Network (CAN) bus. The experimental results demonstrated that the system's performance was comparable to that of the point-cloud-algorithm-based bin-picking system, while also exhibiting greater stability. Notably, the cost of the controller was significantly reduced, and the embedded hardware and software design ensured stability and adaptability for deployment in demanding settings, such as small-scale heavy industry factories. [ABSTRACT FROM AUTHOR]

In order to understand the mechanism of the ferromagnetism in the ferromagnetic semiconductor Ga 1 − x Mn x As [(Ga,Mn)As], we have investigated the magnetic behavior on a microscopic level through systematic temperature (T)- and magnetic field (H)-dependent soft x-ray magnetic circular dichroism (XMCD) experiments at the Mn L 2 , 3 absorption edges. The T and H dependences of XMCD intensities have been analyzed using a model consisting of the ferromagnetic (FM), paramagnetic, and superparamagnetic (SPM) components. Intriguingly, we have found a common behavior for the ferromagnetic ordering process in (Ga,Mn)As samples with different Mn concentrations (4% and 10.8%) and different Curie temperature (T C ) values (65, 120, and 164 K). In particular, the SPM component develops well above T C , indicating that local FM regions are formed well above T C . The present findings indicate that the onset of ferromagnetic ordering is triggered by local electronic states around the substitutional Mn ions rather than uniform electronic states considered by mean-field theories. Insight into the most representative ferromagnetic semiconductor, (Ga,Mn)As, provided by the present study will be an important step in understanding the mechanism of ferromagnetic ordering in various ferromagnetic semiconductor families. [ABSTRACT FROM AUTHOR]

One of the most common systems in non-automated warehouses, is drive-in pallet racking with a shared storage policy (which is usually based on the duration-of-stay). Such scheme targets towards an efficient use of storage space, since its operation costs are directly related to the size and layout of the warehouse. In this paper, two mathematical programming models and two greedy-randomised based heuristics for finding (nearly) optimal storage and retrieval operation sequences for this type of storage system are proposed. The computational effectiveness of the proposed approaches is measured by considering two sets of synthetic instances. The obtained results show that the proposed heuristics are not only able to compute high-quality solutions (as observed when being compared with the optimal solutions attained by the mathematical programming models), but it is also capable of providing solutions in very short running times even for large instances for which the mathematical programming model failed to find feasible solutions. At the light of these results, the best heuristic is also tested using a rolling-horizon planning strategy in a real-world case study, obtained from a Chilean company. It turns out that the attained results are more effective than the company's current storage policy. [ABSTRACT FROM AUTHOR]

This paper investigates manual order picking, where workers travel through the warehouse to retrieve requested items from shelves. To minimise the completion time of orders, researchers have developed various routing procedures that guide order pickers through the warehouse. The paper at hand contributes to this stream of research and proposes an optimal order picker routing policy for a conventional warehouse with two blocks and arbitrary starting and ending points of a tour. The procedure proposed in this paper extends an earlier work of Löffler et al. (2018. Picker routing in AGV-assisted order picking systems, Working Paper, DPO-01/2018, Deutsche Post Chair-Optimization of Distribution Networks, RWTH Aachen University, 2018) by applying the concepts of Ratliff and Rosenthal (1983. "Order-picking in a Rectangular Warehouse: a Solvable Case of the Traveling Salesman Problem." Operations Research 31 (3): 507–521) and Roodbergen and de Koster (2001a. "Routing Order Pickers in a Warehouse with a Middle Aisle." European Journal of Operational Research 133 (1): 32–43) that used graph theory and dynamic programming for finding an optimal picker route. We also propose a routing heuristic, denoted S*-shape, for conventional two-block warehouses with arbitrary starting and ending points of a tour. In computational experiments, we compare the average order picking tour length in a conventional warehouse with a single block to the case of a conventional warehouse with two blocks to assess the impact of the middle cross aisle on the performance of the warehouse. Furthermore, we evaluate the performance of the S*-shape heuristic by comparing it to the exact algorithm proposed in this study. [ABSTRACT FROM AUTHOR]

The shuttle-based storage and retrieval system (SBS/RS) is a relatively new part-to-picker order picking system. We have developed a performance estimation and design algorithm for the SBS/RS. The performance estimation is based on a queuing model. The design algorithm aims to find the minimum cost configurations in terms of number of tiers, aisles, lifts and workstations with given throughput, tote capacity and order cycle time requirements. We used simulation driven by parameters abstracted from an actual SBS/RS to verify the performance estimation, and applied the design algorithm in the case study. The results indicate that: (1) compared to simulation results, the throughput of the performance estimation is nearly identical when the arrival rate is below the maximum capacity; (2) the design algorithm yields a configuration with 28.1% cost reduction in the current system. In addition, we also compared the shuttle system with the competing robotic order fulfilment system (robotic system in short) in terms of facility cost, building cost and order cycle time. We found that the shuttle system is a better choice if large storage capacity and high throughput are required whereas the robotic order fulfilment system performs better if small storage capacity and low throughput are required. [ABSTRACT FROM AUTHOR]

With new market developments and e-commerce, there is an increased use of and interest in automation for order picking. This paper presents a systematic review and content analysis of the literature. It has the purpose of understanding the relevant performance aspects for automated, or partly automated, OPSs and identifying the studied links between design and performance, i.e. identifying which combinations of design aspects and performance aspects have been studied in previous research. For this purpose, 74 papers were selected and reviewed. From the review, it is clear that there has been an increased number of papers dealing with the performance of automated, or partly automated, OPSs in recent years. Moreover, there are differences between the different OPS types, but, overall, the performance categories of throughput, lead time, and operational efficiency have received the most attention in the literature. The paper identifies links between design and performance that have been studied, as well as links that appear to be under-researched. For academics, this paper synthesises the current knowledge on the performance of automation in OPSs and identifies opportunities for future research. For practitioners, the paper provides knowledge that can support the decision-making process of automation in OPSs. [ABSTRACT FROM AUTHOR]

We consider rapid cooling processes in classical, three-dimensional, purely repulsive binary mixtures in which an initial infinite-temperature (ideal-gas) configuration is instantly quenched to zero temperature. It is found that such systems display two kinds of ordering processes, the type of which can be controlled by tuning the interactions between unlike particles. While strong inter-species repulsion leads to chemical ordering in terms of an unmixing process, weak repulsion gives rise to spontaneous crystallization, maintaining chemical homogeneity. This result indicates the existence of a transition in the topography of the underlying potential-energy landscape as the intra-species interaction strength is varied. Furthermore, the dual-type behavior appears to be universal for repulsive pair-interaction potential-energy functions in general, with the propensity for the crystallization process being related to their behavior in the neighborhood of zero separation. [ABSTRACT FROM AUTHOR]

In this paper, we propose the concepts of the composition of possibilistic variables and state functions. While in conventional compositional data analysis, the interdependent components of a deterministic vector must add up to a specific quantity, we consider such components as possibilistic variables. The concept of state function is intended to describe the state of a dynamic variable over time. If a state function is used to model decay in time, it is called the ageing function. We present a practical implementation of our concepts through the development of a model for a supply chain planning problem, specifically the order promising process for perishables. We use the composition of possibilistic variables to model the existence of different non-homogeneous products in a lot (sub-lots with lack of homogeneity in the product), and the ageing function to establish a shelf life-based pricing policy. To maintain a reasonable complexity and computational efficiency, we propose the procedure to obtain an equivalent interval representation based on α-cuts, allowing to include both concepts by means of linear mathematical programming. Practical experiments were conducted based on data of a Spanish supply chain dedicated to pack and distribute oranges and tangerines. The results validated the functionality of both, the compositions of possibilistic variables and ageing functions, showing also a very good performance in terms of the interpretation of a real problem with a good computational performance. [ABSTRACT FROM AUTHOR]

This paper reexamines the order picking process in a warehouse facing the challenges that e-commerce brings about and which are characterised by a very large number of small sized orders and returns. Implementing effective storage assignment strategies combined with efficient batching, in this context, is very fundamental to keep the warehouse's responsiveness and order completion times up to the standards. This paper investigates a new storage assignment strategy, initially implemented by a large shoes and footwear wholesaler, to enhance the performance of the order picking process in its warehouses. The impact of this new storage assignment strategy on the performance of the order picking process is analysed via simulation. The performance of the system, measured in terms of total picking time as well as order lead time while taking congestion into account, is compared to the cases where conventional storage assignment strategies are implemented. A full factorial design is set up and the simulation output is statistically analysed. The results of this analysis are reported and thoroughly discussed. Attending to the results, the proposed strategy presents a remarkable potential to shorten total picking travel distances and order completion time and consequently customer satisfaction. [ABSTRACT FROM AUTHOR]

The blocking mitigation mechanism contained in a batching and sequencing model improves order picking performance in bucket brigade order picking systems by adjusting the batch formation in a given batch window. The batch formation of a given batch window affects the transition to the next batch window and limits the batch formation's structure in the next window. In addition, imbalance in picker capability increases the variation of batch formation while mitigating blocking delay. Our paper proposes a dynamic indexed batching model to smooth the transition between consecutive batch windows and give a better approximation of non-identical pickers' capability. We develop a mixed integer programming solution for a dynamic indexed batching model in a bucket brigade order picking system (DIBMB). Simulation experiments show that the DIBMB smooths the transition between batch windows as measured in the delay experienced by the first batch in each batch window. Comparisons to the available batching models show that under DIBMB, the blocking delay gradually increases throughout the sequence of batches. [ABSTRACT FROM AUTHOR]

Cryo-electron microscopy (cryo-EM) is a powerful technique for determining the structures of biological macromolecular complexes. Picking single-protein particles from cryo-EM micrographs is a crucial step in reconstructing protein structures. However, the widely used template-based particle picking process is labor-intensive and time-consuming. Though machine learning and artificial intelligence (AI) based particle picking can potentially automate the process, its development is hindered by lack of large, high-quality labelled training data. To address this bottleneck, we present CryoPPP, a large, diverse, expert-curated cryo-EM image dataset for protein particle picking and analysis. It consists of labelled cryo-EM micrographs (images) of 34 representative protein datasets selected from the Electron Microscopy Public Image Archive (EMPIAR). The dataset is 2.6 terabytes and includes 9,893 high-resolution micrographs with labelled protein particle coordinates. The labelling process was rigorously validated through 2D particle class validation and 3D density map validation with the gold standard. The dataset is expected to greatly facilitate the development of both AI and classical methods for automated cryo-EM protein particle picking. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Summary: Seismic P‐wave first arrival picking is one of the critical problems in seismic source research. At present, the picking of seismic P‐wave first arrival mainly relies on the combination of traditional methods and manual picking. However, traditional algorithms have poor picking performance and low manual picking efficiency, which cannot meet the needs of research and application. Based on the deep learning network InceptionResNet‐V2, this paper proposes an improved network (EQK‐IncResNet) that can be used for seismic P‐wave first arrival picking. Compared with traditional methods, this model does not need to set the threshold manually and only needs to input the three‐component data of the seismic waveform data to intelligently identify the first‐arrival of the seismic P‐wave. This model has a lightweight structure and excellent feature extraction capabilities, which can effectively identify low signal‐to‐noise ratio data. The experimental results show that within the error thresholds of 0.1, 0.3, and 0.5 s, the hit rate of this method is 74.45%, 96.79%, and 98.68%, respectively. The average picking error is 0.031 s, which is better than the traditional methods such as AR‐AIC + STA/LTA and the mainstream deep learning methods such as GRU. [ABSTRACT FROM AUTHOR]

Cellular metabolism (or energetics) and epigenetics are tightly coupled cellular processes. It is arguable that of all the described cancer hallmarks, dysregulated cellular energetics and epigenetics are the most tightly coregulated. Cellular metabolic states regulate and drive epigenetic changes while also being capable of influencing, if not driving, epigenetic reprogramming. Conversely, epigenetic changes can drive altered and compensatory metabolic states. Cancer cells meticulously modify and control each of these two linked cellular processes in order to maintain their tumorigenic potential and capacity. This review aims to explore the interplay between these two processes and discuss how each affects the other, driving and enhancing tumorigenic states in certain contexts. [ABSTRACT FROM AUTHOR]

Organisms experience environmental conditions over contiguous geographic space. However, empirical studies tend to characterize this environment in a way that is discrete and often subjective. Owing to practical limitations, the spatial grain (resolution) at which we record environmental conditions often fails to capture the true environmental variation experienced by a species, therefore hindering estimation of the ecological niches of species. Despite the general awareness of the importance of spatial scale in niche studies, the impact of variable spatial grains in biodiversity and environmental data on ecological and evolutionary inference remains insufficiently appreciated. We illustrate the key drivers and consequences of the grain size-dependence of environmental niche estimates and provide general recommendations on how to address the issue of grain size-dependence in empirical studies. Species environmental niches are central to ecology, evolution, and global change research, but their characterization and interpretation depend on the spatial scale (specifically, the spatial grain) of their measurement. We find that the spatial grain of niche measurement is usually uninformed by ecological processes and varies by orders of magnitude. We illustrate the consequences of this variation for the volume, position, and shape of niche estimates, and discuss how it interacts with geographic range size, habitat specialization, and environmental heterogeneity. Spatial grain significantly affects the study of niche breadth, environmental suitability, niche evolution, niche tracking, and climate change effects. These and other fields will benefit from a more mechanism-informed choice of spatial grain and cross-grain evaluations that integrate different data sources. [ABSTRACT FROM AUTHOR]

Since the manufacturing process of aircraft panel parts resquires accurately extracting the machining allowance, this paper proposes a repair method of panel parts based on the measured point cloud data. First, a feature point detection algorithm based on normal difference is designed to extract the initial feature points of the reference panels. Second, the iterative shrinkage optimization model is established to perform shrinkage optimization on the initial feature points to obtain the final feature points of the reference panels. Finally, registration is performed according to the tooling positioning holes, and after the feature points of the reference panel are mapped to the panel to be repaired, feature points are connected in a certain order to obtain the processing path of the panel to be repaired. Processing is carried out according to the repairing path and the gap of the panels is detected after the assemble. Experimental result show that this method can accurately extract the processing path of the panel to be repaired and after processing verification, and the gap between the wall panels is less than 1.2 mm. [ABSTRACT FROM AUTHOR]

Polycentric organizations allow highly functional, or "group-beneficial," outcomes to emerge from the myopic behavior of rule-guided individuals. How does polycentricity achieve this feat? Drawing on multilevel selection theory, I argue that polycentric orders support successful outcomes by defining group boundaries and reducing within-group fitness variance relative to between-group variance. The Price equation suggests that, by doing so, polycentric orders facilitate a process of collectively beneficial adaptation, including the capacity to evolve mechanisms for monitoring and punishing rule violators. [ABSTRACT FROM AUTHOR]

This paper aims to construct a general framework of coupling tumor–bone remodeling processes in order to produce plausible outcomes of the effects of tumors on the number of osteoclasts, osteoblasts, and the frequency of the bone turnover cycle. In this document, Komarova's model has been extended to include the effect of tumors on the bone remodeling processes. Thus, we explored three alternatives for coupling tumor presence into Komarova's model: first, using a "damage" parameter that depends on the tumor cell concentration. A second model follows the original structure of Komarova, including the tumor presence in those equations powered up to a new parameter, called the paracrine effect of the tumor on osteoclasts and osteoblasts; the last model is replicated from Ayati and collaborators in which the impact of the tumor is included into the paracrine parameters. Through the models, we studied their stability and considered some examples that can reproduce the tumor effects seen in clinic and experimentally. Therefore, this paper has three parts: the exposition of the three models, the results and discussion (where we explore some aspects and examples of the solution of the models), and the conclusion. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department 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 robotic mobile fulfillment system, where mobile robots carry racks to stationary stations for human pickers, is widely used in e-commerce warehouses. The operational efficiency of the system is largely affected by the organization of the order picking process. In this paper, we investigate an order picking tactic in a robotic mobile fulfillment system that allows racks moving between multiple picking stations in order to feed more orders during one visit and therefore save the overall throughput time. To evaluate this operational tactic's effectiveness, we propose a mathematical model to jointly optimize the order assignment, order sequencing, rack selection, and rack sequencing. A two-stage hybrid heuristic algorithm framework is then presented, including order assignment in the first stage and order and rack sequencing in the second stage. We conduct numerical experiments to validate the proposed algorithms' performance under different strategies and find out that the inter-station operation can significantly save order throughput time on the testing cases. We also investigate the effects of several factors, including the number of picking stations, their capacities, the stock keeping unit diversity, and queue length. Furthermore, a solid simulation is carried out to show the rationale of using rack moves as the objective rather than the completion time. [ABSTRACT FROM AUTHOR]