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In order to solve the problems of complex processes, long cycle, high cost and high risk in traditional installation methods of large floating crane jibs, a novel prevent failure method using a gantry crane to install the floating crane jib is proposed and key technologies, such as reasonable solution for distributing force on the lifting point in the jib lifting through adopting balanced suspensory rigging, efficient shaft threading technology with guide and traction device and newly developed compliant support structure against ship rolling. In this article, we present the application cases of systematic installation method of the large floating crane jib to real production process. The engineering practice proves that the novel installation method proposed is simple in operation and low in cost and provides a new and reliable choice for the installation and maintenance of large floating crane. [ABSTRACT FROM AUTHOR]

The violent swinging motion of a payload imposes significant safety problems for the operation of offshore ship-mounted cranes (offshore cranes). We therefore propose a stable experimental hoisting platform for an offshore crane payload positioning system with a parallel cable-driven method (PP-PCDM), and an adaptive cable-drive anti-swing tension (ACAT) control method based on the PP-PCDM is developed to resolve the problem of swinging of the payload by limiting its spatial position. The PP-PCDM enables synchronous tracking of the movement of the payload when the crane is working. When the payload deviates from a stable state due to an external disturbance, the anti-swing cables are immediately retracted or released based on the feedback signal. The spatial position of the payload is then limited by adjusting the length and tension of the parallel cables until the payload appears stationary from the perspective of the ship's deck. Operational safety and efficiency is substantially improved, and the proposed PP-PCDM structure and ACAT control method can be applied to a variety of different types of cranes. The results of simulations and physical experiments show that the anti-swing effect exceeds 89.86%. The PP-PCDM enables excellent performance of synchronous tracking and hoisting assistance, and ensures that the rated lifting weight of the offshore crane is not affected. [ABSTRACT FROM AUTHOR]

The primary objective of this research was to implement a more efficient handling strategy in the container terminal storage yard at the Baltic Hub Container Terminal (BHCT). Following an analysis of the current logistics system associated with starboard-side mooring, an attempt was made to shift the mooring to the port side. Two routing strategies corresponding to the analysed mooring operations were tested using a developed model. Simulations were conducted to enable a comparison of various handling strategies that were suitable for the mooring arrangements and equipment under investigation. This analysis was based on reliable information obtained from a real process. Evaluative criteria for examining the impact of changing the handling strategy of internal movement vehicles (IMVs) in the terminal storage yard in terms of process efficiency included the total time and distance of container transportation and the truck utilisation level. A new route for IMVs was developed to accommodate the changed mooring operation. This adjustment aimed to enhance the discharge process and to reduce the distance travelled, resulting in a reduction in fuel consumption. The shorter travel distance also positively impacted productivity, and contributed to a reduction in operating costs. The changes to the mooring arrangement directly resulted in a 10% increase in the quay crane gross productivity, measured in moves per hour (mph). Given that many ports do not pay attention to how ships are moored, the case study and analysis presented here can help staff quickly improve their handling strategy and productivity, thus increasing the port's competitiveness. [ABSTRACT FROM AUTHOR]

Simple Summary: The gut microbiota plays important roles for maintaining the health of the host. In this study, the results revealed significant differences in the gut bacterial communities among bean geese, hooded cranes, and domestic geese. In comparison to domestic geese, the gut bacterial community of bean geese and hooded cranes had a greater capacity for energy metabolism, suggesting that wild birds may rely more on their gut microbiota to survive in cold conditions. Furthermore, pathogens were discovered to overlap among the three hosts, reminding us to monitor the potential for pathogen transmission between poultry and wild birds. Hooded cranes showed the highest diversity and relative abundance of pathogens compared to the other two species. Due to its vulnerable status, more focus should be paid to the protection of the hooded crane species. These findings could help us gain a deeper understanding of the structure of gut bacterial and pathogenic communities in poultry and wild birds. The host's physiological well-being is intricately associated with the gut microbiota. However, previous studies regarding the intestinal microbiota have focused on domesticated or captive birds. This study used high-throughput sequencing technology to identify the gut bacterial communities of sympatric bean geese, hooded cranes, and domestic geese. The results indicated that the gut bacterial diversity in domestic geese and hooded cranes showed considerably higher diversity than bean geese. The gut bacterial community compositions varied significantly among the three hosts (p < 0.05). Compared to the hooded crane, the bean goose and domestic goose were more similar in their genotype and evolutionary history, with less difference in the bacterial community composition and assembly processes between the two species. Thus, the results might support the crucial role of host genotypes on their gut microbiota. The gut bacteria of wild hooded cranes and bean geese had a greater capacity for energy metabolism compared to domestic geese, suggesting that wild birds may rely more on their gut microbiota to survive in cold conditions. Moreover, the intestines of the three hosts were identified as harboring potential pathogens. The relative abundance of pathogens was higher in the hooded crane compared to the other two species. The hooded crane gut bacterial community assemblage revealed the least deterministic process with the lowest filtering/selection on the gut microbiota, which might have been a reason for the highest number of pathogens result. Compared to the hooded crane, the sympatric bean goose showed the least diversity and relative abundance of pathogens. The intestinal bacterial co-occurrence network showed the highest stability in the bean goose, potentially enhancing host resistance to adverse environments and reducing the susceptibility to pathogen invasion. In this study, the pathogens were also discovered to overlap among the three hosts, reminding us to monitor the potential for pathogen transmission between poultry and wild birds. Overall, the current findings have the potential to enhance the understanding of gut bacterial and pathogenic community structures in poultry and wild birds. [ABSTRACT FROM AUTHOR]

In actual working environments, underactuated overhead cranes are susceptible to the adverse effects of the mechanical friction, uncertain parameters, and other disturbances. In particular, if the payload is disturbed (i.e. the unmatched disturbance), unpredictable swings would occur. Therefore, a discrete time sliding mode predictive control for overhead cranes based on a disturbance observer is proposed. Specifically, to eliminate uncertain disturbances, we propose a disturbance observer to estimate and compensate the disturbance to the input channel. Then, a new discrete sliding mode control law is obtained by adding the disturbance error estimator to the discrete sliding mode surface. In order to reduce the chattering inherent in the sliding mode, we integrate the discrete sliding mode law into the model predictive control, and use the rolling optimization and feedback correction of the predictive control, and finally output the optimal control law to act on the system. This control method can not only further improve the control accuracy, but also has sufficient robustness. Simulation and robustness experiments under various conditions verify the effectiveness of the proposed controller. [ABSTRACT FROM AUTHOR]

On construction sites, the principal means of communication between crane operator and crane signalman is mainly hand signaling. Often these hand signals are received and interpreted incorrectly, leading to communication errors and accidents. This paper describes the development of a sensor-based smart construction glove that uses a 3-axis accelerometer, 3-axis gyroscope, and 3-axis magnetometer to measure the hand's orientation with the help of quaternions, and flex-sensors to measure the intensity of bend in the fingers. The noises in the sensors are removed using a complementary filter fusion algorithm. Four machine-learning models— k -nearest neighbor, support vector machine, decision tree, and convolutional neural network–long short-term memory (CNN-LSTM)—are proposed for crane signalman hand-signal classification. The models are trained, validated, and tested using the sensor data collected from the smart construction glove. The best performance in the test data set is achieved by CNN-LSTM, which is found to achieve a precision of 84.3%, recall of 83.9%, an F1-score of 84%, and an average accuracy of 94.22% in the test data set. For real-time crane signalman hand-signal classification, an Android-based mobile application is developed. The application receives the data in text format from the smart construction glove via Bluetooth and converts it into speech output. The smart construction glove can classify 18 different crane signalman hand signals used on construction sites. The CNN-LSTM model is found to achieve the highest overall accuracy (93.87%) in real-time implementation. [ABSTRACT FROM AUTHOR]

In this paper, a disturbance-observer–based control approach is developed for overhead crane systems. Different from existing control strategies, the issues consisting of the output feedback, input saturation, double-pendulum dynamics, and uncertain disturbances are taken into consideration here. In particular, a disturbance observer is designed first, which can exactly estimate uncertain disturbances. Next, to enhance the performance of the controller, a virtual position signal is constructed and a corresponding Lyapunov function is introduced. Then, based on the provided Lyapunov function and the designed disturbance observer, a composite control approach is developed for overhead crane systems with double-pendulum dynamics and the convergence of the system states is proved via rigorous theoretical analysis. Finally, the effectiveness and robustness of the proposed control approach are verified by simulation tests. [ABSTRACT FROM AUTHOR]

Summary: Telescopic truck crane is an under‐actuated mechanical system with three actuators controlling five outputs. Its complex structure, shape variation, uncertain parameters, elastic cables, and viscoelastic cylinders are great challenges in control design. This article proposes two adaptive robust controllers for such cranes. A control core assures robustness based on back‐stepping and Lyapunov stability. The adaptation is achieved by employing model‐reference adaptive and self‐tuning control approaches. Thus, the benefits of these adaptive techniques are introduced into the control systems. The application to a practical crane shows the effectiveness of the proposed controllers. The crane has robustness and adaptation despite the elasticity and friction of the load‐carrying cable, the viscoelasticity of the cylinders, the variation of crane parameters, and the presence of winds. Comprehensive comparison indicates the state of the art and the shortcomings of the control systems. [ABSTRACT FROM AUTHOR]

In this work, we introduce a multi-vehicle (or multi-postman) extension of the classical Mixed Rural Postman Problem, which we call the Min–Max Mixed Rural Postmen Cover Problem (MRPCP). The MRPCP is defined on a mixed graph G = (V , E , A) , where V is the vertex set, E denotes the (undirected) edge set and A represents the (directed) arc set. Let F ⊆ E ( H ⊆ A ) be the set of required edges (required arcs). There is a nonnegative weight associated with each edge and arc. The objective is to determine no more than k closed walks to cover all the required edges in F and all the required arcs in H such that the weight of the maximum weight closed walk is minimized. By replacing closed walks with (open) walks in the MRPCP, we obtain the Min–Max Mixed Rural Postmen Walk Cover Problem (MRPWCP). The Min–Max Mixed Chinese Postmen Cover Problem (MCPCP) is a special case of the MRPCP where F = E and H = A . The Min–Max Stacker Crane Cover Problem (SCCP) is another special case of the MRPCP where F = ∅ and H = A For the MRPCP with the input graph satisfying the weakly symmetric condition, i.e., for each arc there exists a parallel edge whose weight is not greater than this arc, we devise a 27 4 -approximation algorithm. This algorithm achieves an approximation ratio of 33 5 for the SCCP with the weakly symmetric condition. Moreover, we obtain the first 5-approximation algorithm (4-approximation algorithm) for the MRPWCP (MCPCP) with the weakly symmetric condition. [ABSTRACT FROM AUTHOR]

An overhead crane system is a complex time-varying system if it includes simultaneous hoisting and moving operations. To address the problem that time-varying systems usually have no exact analytical solution, an anti-swing method based on linear approximation of the phase plane trajectory is proposed. Specifically, the phase plane trajectory of the swing angle is first analyzed and it is found that the double-step acceleration method with unequal acceleration amplitude and acceleration time has a combination of limit loops in the phase plane trajectory of the swing angle when the rope length varies, so the average rope length of each section is used to approximate the natural oscillation frequency. Next, the input shaping technique is used to shape the input signal into the desired output signal so that the load swing angle can follow the planned trajectory. The desired acceleration amplitude and switching time are then derived based on the geometric relationship between the swing angle in the phase plane and the specific physical constraints. Finally, the feasibility of the proposed method is verified by numerical simulations. [ABSTRACT FROM AUTHOR]

This study addresses the quay crane scheduling problem (QCSP), which involves scheduling a fixed number of quay cranes to load and unload containers from ships in a maritime container terminal. The objective is to minimize the completion time while adhering to precedence, safety margin, and noncrossing constraints. Efficient scheduling of quay cranes plays a crucial role in reducing the time vessels spend at terminals. To solve the QCSP, we explore different schedule directions for the quay cranes. Specifically, we consider three directions: unidirectional, where the quay cranes maintain a consistent movement direction from upper to lower bays or vice versa after initial repositioning; bidirectional, allowing the cranes to change direction once during operations; and multidirectional, permitting freely changing movement direction during operations. For the bidirectional QCSP, we propose a new compact mathematical formulation. To obtain valid lower bounds on the optimal completion time, we derive various relaxations of this new formulation based on the different schedule directions. Our solution framework employs logic-based Benders decomposition, decomposing the problem into an assignment master problem and operation-sequence slave subproblems. Extensive computational experiments using benchmark instances from existing literature and newly generated instances validate the efficiency and effectiveness of the lower bounds and the exact solution approach. History: Accepted by Andrea Lodi, Area Editor for Design & Analysis of Algorithms–Discrete. Funding: This work was supported by the Major Program of the National Natural Science Foundation of China [Grants 72192830 and 72192831], the National Natural Science Foundation of China [Grant 72102034], and the 111 Project [Grant B16009]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/ijoc.2022.0298 [ABSTRACT FROM AUTHOR]

Pulleys and cranes are used for hoisting loads with or without providing a significant gain in force. Both of these devices have provided convenience to humans since ancient times. Pulleys are considered to be one of the five mechanical powers of the ancient world. Their history is very much linked with the early history of cranes. The cranes originated from the pulley systems. In this paper, the early history of the application of these well-preserved ancient mechanical instruments is examined together. This paper mainly focuses on the various interesting applications of pulleys and cranes in ancient and medieval times. Yet theoretical developments in the timeline mentioned above are also included in this paper. [ABSTRACT FROM AUTHOR]

This study addresses the critical gap in the literature regarding the energy efficiency of intermodal terminals in smart cities, mainly focusing on crane operations during train loading processes. Novelty's contribution lies in developing a comprehensive simulation model in FlexSim, where quantitative analysis of crane energy consumption, factoring in container location in the storage yard, rehandling operations, and crane movement strategies were performed. Moreover, the analysis of hoist, trolley, and gantry movements was performed to evaluate their impact on overall container loading process energy efficiency. The findings reveal that the choice of train loading method significantly influences crane energy consumption, thereby affecting the operational costs, environmental footprint, and energy efficiency of the logistics hub in the form of an intermodal terminal. This research provides a methodology for assessing and enhancing the energy efficiency of intermodal terminals and highlights the broader implications for smart city sustainability goals, including reduced greenhouse gas emissions, lower operating costs, and improved transportation infrastructure. The outcomes of this research can possibly support smart city planners and logistics managers in making informed decisions to optimise intermodal terminal operations, contributing to urban areas' sustainable development and economic resilience. [ABSTRACT FROM AUTHOR]

Thermal soaring conditions above the sea have long been assumed absent or too weak for terrestrial migrating birds, forcing obligate soarers to take long detours and avoid sea-crossing, and facultative soarers to cross exclusively by costly flapping flight. Thus, while atmospheric convection does develop at sea and is used by some seabirds, it has been largely ignored in avian migration research. Here, we provide direct evidence for routine thermal soaring over open sea in the common crane, the heaviest facultative soarer known among terrestrial migrating birds. Using high-resolution biologging from 44 cranes tracked across their transcontinental migration over 4 years, we show that soaring performance was no different over sea than over land in mid-latitudes. Sea-soaring occurred predominantly in autumn when large water-air temperature difference followed mid-latitude cyclones. Our findings challenge a fundamental migration research paradigm and suggest that obligate soarers avoid sea-crossing not due to the absence or weakness of thermals but due to their low frequency, for which they cannot compensate with prolonged flapping. Conversely, facultative soarers other than cranes should also be able to use thermals over the sea. Marine cold air outbreaks, imperative to global energy budget and climate, may also be important for bird migration. [ABSTRACT FROM AUTHOR]

Due to the doping of considerable noise and impact components in vibration signals of quay crane gearboxes, some traditional methods have difficulty uncovering degradation patterns. To accurately extract degradation features from vibration monitoring signals, a degradation feature extraction technique based on static divided symbol sequence entropy is proposed. Based on the basic scale entropy technique, considering the uniformity of the symbolization standard, the technique takes the root mean square of the health condition signal as the basis and incorporates the scale coefficient to establish a uniform basic scale. Simultaneously, the symbol set is expanded to enhance the information content and the ability of the approach to characterize the complexity levels of signals in large-value regions. Therefore, the proposed static divided symbol sequence entropy technique can accurately and flexibly characterize performance degradations. The logistic chaotic sequence and the lifetime signal of hoisting mechanism gearbox are separately used for analysis. It shows that the proposed technique can characterize the complexity of the nonlinear time series and sensitively describe the performance degradation exhibited by hoisting mechanism gearbox. This technique is computationally fast, and it can be implemented as a foundation for developing new methods for evaluating the health conditions of quay crane gearboxes. [ABSTRACT FROM AUTHOR]

The reintroduction of Siberian cranes bred in the Oka Crane Breeding Center of Oka State Nature Reserve, Ryazan region, has been underway for 30 years. During this time, 47 eggs were placed in the nests of Eurasian cranes and 190 chicks were released into the wild, including 57 in the pre-migratory staging areas of Eurasian cranes. In order to optimize breeding methods and reduce risks when releasing Siberian crane chicks, it is necessary to take into account the results of work on the reintroduction of Whooping and Red-crowned cranes, as well as to consider the characteristics of the biology of the Eurasian crane. [ABSTRACT FROM AUTHOR]

Forestry cranes are of paramount importance in forestry operations, so considerable efforts have been carried out to improve their performance in recent years. However, all these efforts have focused on automation technology, leaving aside other alternatives for improvement. Among these alternatives is model-based design, which has the potential to be game-changing for the forest industry. Because research on model-based design is almost non-existent for forestry cranes, there are many gaps that should be filled before presenting improved designs of forestry cranes. The purpose of this article is to fill two of those gaps: (1) the high cost-benefit ratio and safety concerns when testing new designs, components or algorithms in industrial-scale forestry cranes and (2) the dynamic modeling of forestry cranes as mechanical systems with closed kinematic chain. Under these premises, this article first presents a reduced-scale platform resembling a forwarder crane with closed-kinematic chain, where the components of the mechanical structure are manufactured with 3D printing technology, and second, the modeling and experimental validation of the reduced-scale forwarder, where the closed kinematic chain is considered as a system of multiple constrained open kinematic chains. For the experimental validation, a comparison between both experimental and simulation results is presented. Results presented in this article broaden the options to design and test new concepts and/or technology to improve forestry cranes performance. [ABSTRACT FROM AUTHOR]

Kawabata Yasunari's (1899–1972) narrative about the tea ceremony has had a complicated reception, largely because of two factors: its early publication history; and the theft, in early 1954, of the notes that Kawabata would have used for completing the text. Kawabata Yasunari's novel Senbazuru (1952), at the urging of the critic Nakamura Mitsuo, was published in book form before serialization had finished. The sequel to Senbazuru, later titled Namichidori (serialized 1953–1954), was still unfinished when Kawabata's notes were stolen, and he left the text in a state that he himself described as mikan, 'incomplete'. The seemingly unresolved quality of the text is even more apparent when one considers that the two last-written chapters of Namichidori were subsequently not included in published versions of that text, giving the impression that the sequel to Senbazuru ends inconclusively. The present essay examines the narrative as a whole, inclusive of the two concluding chapters. The theory of finance in literature is applied to a pivotal episode near the end of Namichidori (characters invest in the stock market); and thing theory is used to show that, in crucial ways, the narrative ends conclusively, if all the extant chapters are read as a whole. [ABSTRACT FROM AUTHOR]

The methods of periodically non-stationary random processes were used to analyze the vibrations of the damaged bearing unit of the lifting mechanism. To identify and analyze the periodical nonstationarity of the first and second orders the least squares method was used. Based on the calculated parameters, which describe the structure of periodical nonstationarity, a conclusion about the type of defect and its development was drawn. [ABSTRACT FROM AUTHOR]

Cranes are used extensively in manufacturing workshops to move jobs, but their high complexity and dynamics lead to difficult workshop production scheduling. To address this issue, this article proposes a deep reinforcement learning-based method combined with discrete event simulation to minimize the makespan of the double-deck traversable crane flexible job-shop scheduling problem (DTCFJSP). Specifically, the problem is first formulated as a finite Markov decision process by introducing state representation, an action space and a reward function. Then, a new double-deep Q-learning network is incorporated to create a selection strategy for optimal actions in different states. The results of experiments conducted in this study show that the average efficiency of the double-deck traversable crane is approximately 12% higher than that of regular cranes, and the application of deep reinforcement learning in crane scheduling is feasible and effective. [ABSTRACT FROM AUTHOR]

At present, the intelligent foundation of China's ports is relatively insufficient, especially in the intelligent management and control of automated container ports, the efficiency of port operation and related technologies of intelligent management are relatively backward. In this context, the research focuses on the yard crane scheduling which plays an important role in the automated container port. Unlike the traditional yard crane scheduling, the strategy of transporting containers on both sides of the bays was adopted to avoid the waiting time caused by the container trucks entering and exiting in the single side channel. A mathematical model of single yard crane scheduling model was constructed in this paper, and an improved genetic algorithm was introduced to dynamically adjust the selection and variation parameters according to the characteristics of the fitness distribution of the candidate set, which reduce the problem of decreasing population diversity during the iteration of the algorithm and improve the ability of the algorithm to solve the optimal solution. Finally, the verification by example shows that this model can effectively improve the efficiency of yard crane scheduling task completion, reduce the total time required for scheduling, and improve the efficiency of port yard crane scheduling on the basis of traditional models. [ABSTRACT FROM AUTHOR]

The static design of foundations for tower cranes is mostly based on calculations of structural safety like tilting, sliding and groundbreaking. Settlement calculations for evaluating the inclination of the crane, which is restricted by the suppliers of tower cranes , are essential for safe and economic foundation solutions, too. Based on the experience of more than 280 tower crane positions throughout Austria and Germany the method of Müllner & Meister has been extended satisfying the normative and crane specifically requirements and represents an obligation of one of the biggest building contractors in Europe in the sense of today's resource‐saving management. [ABSTRACT FROM AUTHOR]

The paper presents an extended (in comparison with previous studies) analysis of the population genetic structure of a migratory wide-range species with high abundance, the Eurasian crane, Grus grus L. Using seven highly polymorphic microsatellite loci, high and very similar values of genetic diversity parameters were obtained in samples of the western (G. g. grus) and eastern (G. g. lilfordi) subspecies. Coefficients of genetic differentiation between these subspecies (FST = 0.008, GST = 0.002) were also found to be low. According to AMOVA, 99% of genetic variation of G. grus is attributed to individual levels. Using the Bayesian clustering algorithm implemented in the STRUCTURE software, no clear population genetic structuring of the species was revealed. At the same time, visualization of spatial patternts of genetic variability in the Geneland software showed the presence of a cluster of "pure" subspecies of G. g. grus and G. g. lilfordi, surrounding a cluster of individuals from the zone of intergradation of these subspecies. This result, along with the observed very low F-statistics values, may indicate subtle genetic differences between the cranes from the studied area, possibly having a mutational nature. Lower allelic richness and lack of private alleles in the eastern subspecies G. g.lilfordi suggests its relative evolutionary youth and recent origin from the eastern marginal populations of the nominative western subspecies. [ABSTRACT FROM AUTHOR]

This paper introduces a method to navigate the tower crane movement and suppress the payload swing synchronously. Special error signals are introduced, which bring the coupling of dynamics among various states of the crane and enable the control to meet the synchronous operation in practice. The special angle-dependent energy functions are designed as the candidate sub-Lyapunov functions for decoupling the states. The controller is then stepwise designed with the help of the dynamics model. The stability of the control is proven in the Lyapunov sense. Extensive simulations and experiments have been carried out to demonstrate the effectiveness of the proposed nonlinear coupling control. A popular control approach in the literature is chosen to compare with the current work. It is found that the proposed control is quite effective in suppressing the payload swing while tracking the pre-determined path at the same time. [ABSTRACT FROM AUTHOR]

The crossbeam is frequently subjected to alternating loads during work as an essential load-bearing part of the crane. However, due to the large volume and the limitations of detection technology, it is impossible to realize online monitoring of the mechanical state. The ongoing advancement of ROMing and digital twin technology plays a pivotal role in facilitating the resolution of this particular issue. In this paper, we take the crane beam as the physical entity and combine the Twin Builder reduced-order technology and Deployer digital twin deployment technology to establish a digital twin of the beam. The load recognition model within the twin system exhibits a prediction error rate of ±5%. Furthermore, the accuracy of the ROM surpasses that of conventional machine learning models by a factor of 25. Upon deployment on the web platform, the results are delivered within 0.5 s, representing a substantial improvement as it is merely 1/15 of the time required for traditional 3D displays. The digital twin online monitoring system has the advantages of high accuracy and low requirements for monitoring equipment, which can be widely used in engineering practice to solve the problem that the mechanical state of large parts cannot be accurately monitored online. [ABSTRACT FROM AUTHOR]

The conventional bridge crane hoisting control method is limited by the complex factors of working conditions and generally adopts cumbersome off-line planning. In view of the problem of the inertia swing of the load caused by the trolley hauling the lifting rope during the transportation of the bridge crane, the trajectory off-line planning methods with the open-loop bring the control parameters to be complicated and tedious. A novel trajectory online planning and under-actuated control method on positioning and anti-swing for the bridge crane is proposed. According to the smooth positioning trajectory, the relationship among the motion parameters of the trolley, load swing angle, and other model parameters in the dynamic model are analyzed. With the dynamic coupling relationship between trolley motion and load swing, the function of anti-swing is designed online without changing the positioning performance. The trajectory online planning of the positioning and anti-swaying is accomplished. With the experimental and programming, the proposed method is compared with other different planning methods. The results show that this method can effectively realize the positioning and eliminating pendulum, and has the convenience of online adjusting parameters and fast response. [ABSTRACT FROM AUTHOR]

The traditional anti-swing control algorithm does not consider the coupling between the change of rope length and the swing angle when solving the swing problem of the work boat. As a result, the swing amplitude of the work boat is increased. Aiming at the above problems, a trajectory tracking strategy of PD control considering rope changes is proposed. Firstly, a nonlinear system model with rope change rate is constructed to describe the transient response characteristics of the external disturbance torque and control stability torque of the marine crane. Then, the model is constrained linearly according to the underdrive characteristics of ship crane. The simulation results show that the average swing amplitude of the working boat is reduced by 63.05% and that of the reverse one by 62.03%. [ABSTRACT FROM AUTHOR]

Since 2005, large areas have been planted for maca, the introduced cash crop, on cropland and grassland in Yunnan, China. While cash crops offer clear economic benefits over conventional crops, they also reduce the amount of land for wildlife, especially wading birds. The effect of cash crops on the energetic carrying capacity for birds requires evaluation. The black‐necked crane (Grus nigricollis) is a flagship species wintering in northeast and northwest Yunnan where large areas of cropland and grassland have been converted to maca production. Understanding changes in the energetic carrying capacity in response to increasing maca production will facilitate the development of effective conservation plans for the protection of black‐necked cranes. We estimated food density and the crane's daily energy requirements by observing the foraging behavior of crane individuals using telescopes and recorded video to measure the energetic carrying capacity of the black‐necked crane in the Dashanbao National Nature Reserve. The monthly energetic carrying capacity was similar between the pre‐expansion planting period for maca (2012–2014) and the expansion planting period (2014–2015). The abundance of invertebrates in grassland in December and January and Tartary buckwheat in March was below the food density threshold (below which foraging becomes energetically unprofitable) in both the pre‐and post‐maca planting years. In addition, the crop yield was significantly affected by freeze damage in spring. Thus, climate and abundance of invertebrates affect the energetic carrying capacity of black‐necked cranes in Dashanbao Reserve. We suggest that the local relevant departments should fully assess the potential effect on the cranes when implementing the large‐scale cultivation of introduced crops and avoid the large‐scale planting of single‐species crops. The largest planted area in suitable farmland within the study area should not exceed 1,000 ha. Maca planting should be undertaken with caution in this area because of the potential effect on black‐necked cranes. [ABSTRACT FROM AUTHOR]

Are religious commitments beliefs or some other kind of mental state? Do religious affirmations express beliefs or other non-doxastic attitudes? These questions have been prominent in philosophical research on the language and psychology of religion since the mid-twentieth century, but the history of interest in these topics traces back to late antiquity. In a recent paper, Tim Crane approaches these questions from the perspective of research on theories about the nature of belief. According to some accounts, he argues, the attitudes that we call religious "beliefs" do not exhibit the properties requisite for belief. He raises grounds for dissatisfaction with the proposed account of belief and cognate debates about cognitivism and non-cognitivism, and concludes by setting out a more descriptive approach as the basis for an understanding of religious attitudes. This paper argues that Crane's argument relies on an unduly demanding theory of belief. However, the concerns that he raises about the belief status of religious commitment can be motivated – and are extensively debated – in recent research on religious faith. Crane's characterisation of the cognitive/non-cognitive debate is also disputed. The paper concludes by raising concerns about Crane's description of the scope of the field of religious language. [ABSTRACT FROM AUTHOR]

This paper argues that even Crane's modified account of belief doesn't do justice to all varieties of religious belief. Particularly beliefs associated with ritual behavior don't seem to match the criteria of Crane's alternative account. So, the question remains whether these beliefs should still be called beliefs, or whether the standard model of belief is even more false than Crane suspects. [ABSTRACT FROM AUTHOR]

This comment raises two worries for Crane's view of religious beliefs and their contents. First, I argue that his appeal to inferentialism about the contents of dispositional beliefs cannot fully avoid the problem of inconsistent beliefs. For the same problem can be raised for occurrent thought, and the inferentialist solution is not available there. Second, I argue that religious beliefs differ from ordinary beliefs with respect to their justification in cases of peer disagreements. This suggests that noncognitivism about religious beliefs, which Crane opposes, is the correct view after all. [ABSTRACT FROM AUTHOR]

The green and sustainable development of ports is an issue of great concern to governments, industries, and academia. Carbon emissions near ports mainly come from ships and trucks. The effective allocation of resources and the implementation of a carbon tax policy may reduce carbon emissions near ports. Therefore, this paper investigates an integrated optimization problem of berths, quay cranes, and yard spaces allocation for tidal ports with channel capacity constraints under carbon tax policy. A mathematical model that aims to minimize the sum of the total carbon emission costs and total penalty costs is proposed. To solve the model efficiently, a heuristic algorithm based on the sequential method is developed. Numerical experiments are performed to verify the efficiency of the proposed algorithm. Based on the results of numerical experiments, some potentially useful managerial implications are outlined. [ABSTRACT FROM AUTHOR]

This paper presents a fault detection and estimation method based on a proportional-integral observer applied to a three-degree-of-freedom mechanical crane. Faults are common in this system and can provoke oscillations that generate a loss of performance and stability. A convex linear parameter varying approach is proposed to stabilize the crane and detect and isolate actuator faults to guarantee the crane's performance. The linear matrix inequalities obtained from candidate Lyapunov functions give sufficient conditions to guarantee the fault estimation method. Finally, numerical simulations are proposed to illustrate the method's performance and applicability. [ABSTRACT FROM AUTHOR]

This paper is concerned with the development of an optimal load-handling trajectory for port cranes. The objective is to minimize load cycle time and reduce energy consumption. Energetic macroscopic representation formalism is used to model a port crane load-handling mechanism. The crane model developed includes the mathematical model, the crane's local control system, and a MATLAB/Simulink model for simulation. The particle swarm optimization algorithm is used to find the set of pareto optimal crane trajectories given the variation in crane size, ship size, and wind speed. Experimental validation of the crane model is conducted by comparing it with a real-world crane. Simulation results show that the optimal crane load trajectory is 38% faster and more productive than the nonoptimal crane load trajectory. Furthermore, the results show that the optimal trajectory reduces the cranes' peak power and energy consumption by 36% when compared with the nonoptimal trajectory. [ABSTRACT FROM AUTHOR]

At present, car ownership is expanding, and parking facilities are insufficient. This problem has plagued people's lives and hindered the development of cities. The stereo garage has become the main way to solve the parking problem. But the existing stereo garage is low in intelligence and low in vehicle entry efficiency. Therefore, in this study, a new vehicle entry strategy for the road stacking stereo garage is designed. GA algorithm is innovatively improved and applied to vehicle strategy optimization. By taking the dual objective function as the fitness function of the algorithm, the access strategy is optimized. Using MATLAB software to simulate and verify each access strategy and its improvement effect. This study provides guidance and data support for seeking the best vehicle access strategy. It has good practical application value for vehicle access in 3D garage. [ABSTRACT FROM AUTHOR]

The Antarctic Peninsula's widespread glacier retreat and ice shelf collapse have been attributed to atmospheric and oceanic warming. Following the initial post-collapse period of retreat, several former tributary glaciers of the Larsen A and B ice shelves have been slowly re-advancing for more than a decade. Here, we use a flowline model of Crane Glacier to gauge the sensitivity of former tributary glaciers to future climate change following this period of long-term dynamic adjustment. The glacier's long-term geometry and speed changes are similar to those of other former Larsen A and B tributaries, suggesting that Crane Glacier is a reasonable representation of regional dynamics. For the unperturbed climate simulations, discharge remains nearly unchanged in 2018–2100, indicating that dynamic readjustment to shelf collapse took ~15 years. Despite large uncertainties in Crane Glacier's past and future climate forcing, a wide range of future climate scenarios leads to a relatively modest range in grounding line discharge (0.8–1.5 Gt a−1) by 2100. Based on the model results for Crane, we infer that although former ice shelf tributaries may readvance following collapse, similar to the tidewater glacier cycle, their dynamic response to future climate perturbations should be less than their response to ice shelf collapse. [ABSTRACT FROM AUTHOR]

The main tower of the bridge span over the river-sea direct ship channel of the Hong Kong-Zhuhai-Macao Bridge is a "dolphin" shaped ultra-large steel structure, which was installed with a double floating crane lifting process which was the first case of such installations in China. The application of this technology realizes the control of construction quality and schedule, and improves the economic benefit remarkably. However, the overall lifting process with floating cranes is extremely difficult due to the large overall weight and length of the whole element. Therefore, the hoisting technology of the steel cable tower of the bridge span over the river -sea direct ship channel is comprehensively analyzed, the key control points and the application effect of the overall hoisting of the large steel cable tower are discussed, providing a reference for the construction and management of the large bridge tower of similar cross-sea projects in the future. [ABSTRACT FROM AUTHOR]

Research regarding how birds respond to the installation of cameras at nest sites is limited. We installed cameras at nests of Sandhill Cranes Antigone canadensis (Linnaeus, 1758) and federally endangered Whooping Cranes Grus americanaLinnaeus, 1758 in Juneau County, WI, as part of an ongoing study monitoring the reproductive success of Whooping Cranes in WI. The eastern population of Sandhill Cranes has grown, while Whooping Crane population growth has been slow, prompting the need to monitor the reproductive success of cranes on the refuge. We recorded the flight initiation distance during camera installation, the return time after camera installation, as well as measured the distance at which cameras were placed from each nest. We included temperature at camera deployment, age of nest, mode of access, ordinal date, and year in statistical regression models. We found an apparent difference in the observed flight initiation distances between the two species. Sandhill Cranes allowed researchers to approach their nests closer than Whooping Cranes prior to flushing. The post-disturbance return time was influenced by how far away the cameras were placed from the nest and the ambient temperature during camera deploy. Our study may help inform decisions regarding species response to methods and distance when deploying cameras, especially for endangered or disturbance-sensitive species. [ABSTRACT FROM AUTHOR]

The 1915Çanakkale Bridge spans the Dardanelles at the western end of the Sea of Marmara. Part of the Kinali–Balikesir motorway in the northwest of Turkey, it is the longest suspension bridge in the world. The 2023 m long main span leaves a 1600 × 70 m navigation channel. Two 318 m steel towers support the main suspension cables at 38 m separation. The deck comprises a pair of 14.5 m wide, 3.5 m deep aerofoil steel box girders connected at intervals by transverse box girders. Eight 450 t capacity lifting gantries were required for deck erection, two for each side span and four for the main span. There were 153 deck segments to be erected, of which 143 were erected with the gantries. The gantries were self-erected onto the main cables. Environmental conditions and maritime traffic in the strait were key factors in the development and choice of construction methods for the bridge. This paper describes deck erection with the lifting gantries and focuses on the development, design, testing and operation of the self-erection system – an innovative solution which maximises pre-assembly off the critical path, minimises disruption to shipping and allows installation of the gantries without floating cranes. [ABSTRACT FROM AUTHOR]