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Frontal carrier is often used to stack and transfer containers at freight terminals or inland transfer stations, and the requirement of its security is increasing. Since the lifting point is located in front of the vehicle body, it is also necessary to move the spreader left or right in real time to adjust the position of the lifting point during the lifting process. While the boom extends forward and the lifting load is large, the front carrier will be in a state of unbalanced stress, which increases the hidden danger of the front carrier overturning forward. This paper analyzes the influence of spreader offset on the change of overturning line of the frontal carrier while the frontal carrier is lifting a large load, establishes the coefficient to measure the anti-overturning stability of the frontal carrier, calculates the real-time lifting point position of the frontal carrier, and analyzes the spatial force system of the frontal carrier. By comparing the influence of spreader offset on the anti-overturning stability coefficient of the frontal carrier under different typical lifting conditions, this paper analyzes the change of anti-overturning stability coefficient, and gives the stability area diagram under given load, which provides a certain judgment basis for the safe operation of the frontal carrier.

In order to promote the devices belonging to different users to participate in cooperative communication in D2D networks, a time slot sharing cooperation strategy based on game theory is proposed. At first, the cooperative communication between devices which help each other to relay data is established based on sharing time slots. Secondly, the time slot sharing problem is analyzed by using Nash bargaining method of game theory. Meanwhile, the length of time slot which is used to relay the other devices is obtained by adopting Lagrange multiplier method. Thus, the problem that the devices how to cooperate is solved. Finally, the cut-off conditions of devices cooperation is derived, and the problem that devices when to cooperate is solved. Simulation results show that，compared with the direct transmission mode, the proposed strategy can improve energy efficiency of the devices effectively.

A prominent ocean region exhibiting depleted oxygen concentration is the northern Indian Ocean, whose projected deoxygenation trend in response to climate change requires a comprehensive understanding of the roles of ocean dynamics. We present newly compiled in situ data across platforms (e.g. cruises, Argo, buoy) in the Indonesian coasts of Sumatra and Java between 2010–2022. Combined with reanalysis products, our data detect oxygen-depleted waters attributed to the eastward advection of the northern Indian Ocean waters and monsoon-driven coastal upwelling. Oxygen limited zones (OLZs, DO < 60 μmol kg-1) occupy various depths off the Sumatra-Java coasts, in which dissolved oxygen (DO) reaches ~40 μmol kg-1 in northwest Sumatra. The eastward propagating Equatorial Counter Current plays a major role in delivering the oxygen-depleted waters during the boreal summer; similarly, the South Equatorial Counter Current in the winter monsoon and the Wyrtki Jet during the transition months. Coastal upwelling regulates DO variations via primary production and the respiration of organic matter at intermediate depths in southern Java as the upwelled waters being advected westward towards Sumatra in the summer monsoon. Indonesian Throughflow with enriched organic matter modifies the oxygenated-depleted waters at its outlets. We observe a trend towards deepened OLZ in western Sumatra, while positive Indian Ocean Dipole events (2006, 2012, 2015, 2019) lower DO in the thermocline depths of southern Java on the interannual timescale. Altogether, high-resolution observational biogeochemical data are key to advance our understanding of dynamical DO changes in the southeastern tropical Indian Ocean under the global deoxygenation trend. [ABSTRACT FROM AUTHOR]

On the basis of taking 2K-H type helical differential gear train as the basic prototype,by analyzing the transmission efficiency of its transformation part and piecewise integration in meshing range,the result of the meshing efficiency of the internal and external contacted helical gears from the actual helical gears meshing is got. At the same time,the concept of the ideal machine is introduced,with the consideration of the axial overlap of the helical gear and the gear on the frictional engagement of the power loss,the formula of the helical gear differential gear train transmission efficiency is deduced. By using the given example numerical,theoretical value of the gear train efficiency is calculated,and this result is consist with the simulation result obtained by MATLAB and ADAMS software co-simulation calculation. The method can be used for calculating the efficiency of the other type helical differential gear train.