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The purpose of this paper was to present a soft landing control strategy for a biped robot to avoid and absorb the impulsive reaction forces (which weakens walking stability) caused by the landing impact between the swing foot and the ground.

First, a suitable trajectory of the swing foot is preplanned to avoid the impulsive reaction forces in the walking direction. Second, the impulsive reaction forces of the landing impact are suppressed by the on-line trajectory modification based on the extended time-domain passivity control with admittance causality that has the reaction forces as inputs and the decomposed swing foot’s positions to trim off the forces as the outputs.

The experiment data and results are described and analyzed, showing that the proposed soft landing control strategy can suppress the impulsive forces and improve walking stability.

The main contribution is that a soft landing control strategy for a biped robot was proposed to deal with the impulsive reaction forces generated by the landing impact, which enhances walking stability.

This paper aims to present a control strategy that eliminates the longitudinal and lateral drifting movements of the coaxial ducted fan unmanned helicopter (UH) during autonomous take-off and landing and reduce the coupling characteristics between channels of the coaxial UH for its special model structure.

Unidirectional auxiliary surfaces (UAS) for terminal sliding mode controller (TSMC) are designed for the flight control system of the coaxial UH, and a hierarchical flight control strategy is proposed to improve the decoupling ability of the coaxial UH.

It is demonstrated that the proposed height control strategy can solve the longitudinal and lateral movements during autonomous take-off and landing phase. The proposed hierarchical controller can decouple vertical and heading coupling problem which exists in coaxial UH. Furthermore, the confronted UAS-TSMC method can guarantee finite-time convergence and meet the quick flight trim requirements during take-off and landing.

The designed flight control strategy has not implemented in real flight test yet, as all the tests are conducted in the numerical simulation and simulation with a hardware-in-the-loop (HIL) platform.

The designed flight control strategy can solve the common problem of coupling characteristics between channels for coaxial UH, and it has important theoretical basis and reference value for engineering application; the control strategy can meet the demands of engineering practice.

In consideration of the TSMC approach, which can increase the convergence speed of the system state effectively, and the high level of response speed requirements to UH flight trim, the UAS-TSMC method is first applied to the coaxial ducted fan UH flight control. The proposed control strategy is implemented on the UH flight control system, and the HIL simulation clearly demonstrates that a much better performance could be achieved.

An index language usually incorporates various methods for improving recall and/or precision when searching. Recall devices tend to increase the size of retrieved document sets, while precision devices tend to reduce them. The most common recall and precision devices are described in general terms and their usage in several thesauri is examined. The thesauri looked at relate to databases available for searching in the ESA IRS online information system at one time or another and include the NASA Thesaurus; Thesaurus of Engineering and Scientific Terms; Thesaurus of Metallurgical Terms; Subject Headings used by the USAEC; Subject Headings for Engineering; INIS Thesaurus and the INSPEC Thesaurus. The extent to and the way in which the recall and precision devices are used in the ESA IRS online system for controlled and uncontrolled subject term searching are discussed.

The purpose of this study is to present an optimization-based gait planning method for biped robots according to the conditions of terrain, which takes fully the relationship between walking stability margin and energy efficiency into account.

First, the authors newly designed a practical gait motion synthesis algorithm by using the optimal allowable zero moment point (ZMP) variation region (OAZR), which can generate different gait motions corresponding to different terrains based on the modifiability of ZMP in lateral (y-axis) direction. Second, an effective gait parameter optimization algorithm is performed to find the optimal set of key gait parameters (step length, duration time of gait cycle, average height of center of mass (CoM), amplitude of the vertical CoM motion and double support ratio), which maximizes either the walking stability margin or the energy efficiency with certain walking stability margin under practical constraints (mechanical constraints of all joint motors, geometric constraints, friction force limit and yawing moment limit) according to the conditions of terrain. Third, the necessary controllers for biped robots have been introduced briefly.

The experiment data and results are described and analyzed, showing that the proposed method was verified through simulations and implemented on a DRC-XT biped robot.

The main contribution is that the OAZR has been defined based on AZR, which could be used to plan and generate the various feasible gait motions to help a biped robot to adapt effectively to various terrains.

The purpose of this paper is to develop strategies for potential environmental impacts as a result of institutional arrangement and development of oil palm downstream industry both regionally and nationally.

The research location is in the areas potential for oil palm plantation development, either by plasma through BUMN and BUMS or self-supporting by the society. The research location will be divided into two parts, namely, the land area and the coastal area. The Riau land areas are Regency of Kampar, Rokan Hulu, and Kuantan Singingi, while Riau coastal areas are Regency of Pelalawan, Siak, Bengkalis, Indragiri Hilir, Indragiri Hulu and Rokan Hilir. Both research areas have different productivity due to the different soil fertility levels. The sustainability level of oil palm plantation from the socio-economic and environmental aspects is analyzed using the multi-dimensional scaling approach modified into Rapid Appraisal-Index Sustainability of Palm Oil Management.

In Riau Province, the development of oil palm is quite rapid. This is reasonable for several reasons which include the following supporting factors: the geographical condition of the Riau region is very supportive; the high demand for palm oil derivative products; the existence of market guarantee for oil palm farmers; the higher income oil palm generates than other plantation crops; and the relatively flat area. Most of the problems faced by oil palm farmers are the use of less good seeds, the length of the fruit laying at the location of the plantation, the inadequate production road, the relatively far distance to palm oil mill (POM) (National Agency of Drug and Food Control), the tendency of determining the unilateral revenue of the POM, the collectively measurement of revenue and the general revenue information. The development of oil palm plantations has created an entrepreneurial capability for farmers who are able to capture business opportunities in the agricultural sector, especially the plantation sub-sector.

The originality of this paper shows the comprehensively control strategy, potential of environmental impact and palm oil plantation. The method used for data collection was rapid rural appraisal method because accurate information is needed in a limited time as it relates to decisions related to village development that must be taken immediately. The study area was conducted in Riau Province because Riau Province is one of the biggest palm oil producers in Indonesia. The study sites will be divided into two, namely, the land area and the coastal area.

SUMMARY The paper reviews the requirements for all weather landing systems on a short‐haul jet from the aircraft manufacturer's point of view, with, of course, particular reference to the BAC One‐Eleven. The problems of producing a flexible system which will suit many different types of operator with differing operational environments is discussed. The basic provisions made in the aircraft and the basic automatic system for subsequent easy fitment of all weather landing systems are described and a number of possible alternative systems listed, which build up from the basic single autopilot to a fully automatic all weather landing system. The potentialities of each of these systems in terms of removing existing obstacles to lower minima are tabulated. The major firm BAC One‐Eleven development project —that of safe autoflare—is described. This project is intended to result in the autoflare system being available for airline use in 1966. It is recognized that systems which do not go as far as safe autoflare may confer some benefit—although the benefits to be obtained are hard to predict quantitatively —and may be attractive to some operators. On the other hand a fully automatic failure survival system will almost certainly be required to meet the full Phase III requirement. The ability of the BAC One‐Eleven to accommodate this wide range of possible system requirements is described.

There is an increased research interest in the recent phenomenon of Chinese small and medium‐sized businesses (SMEs) going abroad. The paper aims to enrich the literature by proposing a “Flying High, Landing Soft” curriculum helping Chinese SMEs going abroad. This innovative entrepreneurial curriculum is based on the Soft Landings program originally developed by the National Business Incubation Association. The objective of the curriculum is to provide a platform for students at various levels (undergraduate, graduate, and executive education) and business communities to engage in China‐USA‐Brazil entrepreneurship.

The “Flying High, Landing Soft” curriculum, consisting of three core elements (resources and networks; five steps process of coaching; cultivating storytellers), is grounded in the theories of input‐process‐output model of strategic entrepreneurship and docility‐based distributed cognition.

A “Flying High, Landing Soft” curriculum was developed to help the Chinese SMEs to invest in USA and Brazil. The curriculum is designed to take advantage of resources from the participating entities with the impact of enriching our students' educational experience and enabling business communities to engage in global business opportunities. The “Flying High, Landing Soft” curriculum is a win‐win program for everyone involved.

The curriculum is based on the Soft Landings International Incubator Designation program originally developed by the National Business Incubation Association. Since there is a need for the soft landings companies to go global, there is also a need for students to go global; the “Flying High, Landing Soft” curriculum is a merge of these two concepts.

The authors have developed a curriculum that links China‐USA‐Brazil entrepreneurs, investors, students and institutions to collaborate in order to help individuals to exploit market opportunities as well as use the process to educate students. This form of entrepreneurship curriculum is a contribution to our understanding about entrepreneurship, especially international entrepreneurship of SMEs.

The purpose of this paper is to study the landing performance of the Mars lander considering uncertain landing conditions under two landing modes.

A dynamics analysis model for the legged Mars lander is established for landing simulation, where the nonlinear large-deformation flexible buffer rods are equivalently modeled with a rigid-body mechanism with external forces and movement limit. Sensitivities of the landing stability to various landing conditions are analyzed using the Quasi–Monte-Carlo-based Sobol’ method and computer-aided landing simulations. Moreover, based on the results of sensitivity analysis, sensitive parameters are selected for estimating the safe boundaries for stability indices of rotation and clearance.

It can be concluded from this study that the lander has excellent ability against overturning. The shutdown-before-touchdown strategy helps to maintain than landing pose, and the shutdown-at-touchdown strategy helps to prevent the nozzle from colliding with the surface of Mars.

This study provides a theoretical reference to choose the better landing strategies for Mars landers considering uncertain landing conditions.

A parameterized dynamics Mars lander model and a simplification method are proposed to simulate the landing on Mars. Uncertain landing conditions are parameterized and considered in the dynamics model. Sensitivity analysis and safe boundary methods are used to compare the landing performances with two landing strategies.

This paper analyses the collapse of credit booms into soft landings or systemic banking crises.

A discrete-time competing risks duration model is employed to disentangle the factors behind the length of benign and harmful credit booms.

The results show that economic growth and monetary authorities play the major role in explaining the differences in the length and outcome of credit booms. Moreover, both types of credit expansions display positive duration dependence, i.e. both are more likely to end as they grow older, but hard landing credit booms have proven to be longer than those that land softly.

This paper contributes to our understanding of what affects the length of credit booms and why some end up creating havoc and others do not. In particular, it calls the attention to the important role that Central Bank independence plays regarding credit booms length and outcome.

Accurate glide path tracking is vital to the automatic carrier landing task of unmanned aerial vehicle (UAV). The purpose of this paper is to develop a reliable flight controller that can simultaneously deal with external disturbance, structure fault and actuator fault.

The automatic carrier landing task is resolved into the glide path tracking problem and attitude tracking problem. The disturbance observer-based adaptive sliding mode control scheme is proposed for system stabilization, disturbance rejection and fault tolerance.

Both the Lyapunov method and exemplary simulations can prove that the disturbance estimation error and the attitude tracking error converge in finite time in the presence of external disturbances and various faults.

The presented algorithm is testified by a UAV automatic carrier landing simulation, which shows the potential of practical usage.

The barrier function is introduced to adaptively update both the sliding mode observer gain and sliding mode controller gain, so that the sliding mode surface could converge to a predefined region without overestimation. The proposed flight controller ensures a secure carrier landing task.