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This study aims to propose a novel method based on model learning with sparsity inducing norms for estimating dynamic gravity terms of the serial manipulators. This method is realized by operating the robot, acquiring data and filtering the features in signal acquisition to adapt to the dynamic gravity parameters.

The core principle of the method is to analyze the dictionary composition of the basis function of the model based on the dynamic equation and the Jacobian matrix of an arm. According to the structure of the basis function and the sparsity of the features, combined with joint-angle and driving-torque data acquisition, the effective features of dynamic gravity parameters are screened out using L1-norm optimization and learning algorithms.

The theoretical analysis revealed that training data obtained based on joint angles and driving torques could rapidly update dynamic gravity parameters. The simulation experiment was carried out by using the publicly available robot model and compared with the previous disassembly method to evaluate the feasibility and performance. The real 7-degree of freedom (DOF) industrial manipulator was used to further discuss the effects of the feature selection. The results show that this estimation method can be fully operational and efficient in industrial applications.

This approach is applicable to most serial robots with multi-DOF and the dynamic gravity parameters of the robot are estimated through learning and optimization. The method does not require prior knowledge of the robot arm structure and only requires joint-angle and driving-torque data acquisition under low-speed motion. Furthermore, as it is a data-driven-based method, it can be applied to gravity parameters updating.

Different from previous general robot dynamic modelling methods, the sparsity of the analytical form of dynamic equations was exploited and model learning was formulated as a convex optimization problem to achieve effective gravity parameters screening. The novelty of this estimation approach is that the method does not only require any prior knowledge but also does not require a specifically designed trajectory. Thus, this method can avoid the laborious work of parameter calibration and the induced modelling errors. By using a data-driven learning approach, the new parameter updating process can be completed conveniently when the robot carries additional mass or the end-effector changes for different tasks.

The purpose of this paper is to investigate the design method of partial observer canonical form (POCF), which is one of the important research tools for industrial plants.

Motivated by the two-steps method proposed in Xu et al. (2020), this paper extends this method to the case of Multi-Input Multi-Output (MIMO) nonlinear system. It decomposes the original system into two subsystems by observable decomposition theorem first and then transforms the observable subsystem into OCF. Furthermore, the necessary and sufficient conditions for the existing of POCF are proved.

The proposed method has a wide range of applications including completely observable nonlinear system, noncompletely observable nonlinear system, autonomous nonlinear system and forced nonlinear system. Besides, comparing to the existing results (Saadi et al., 2016), the method requires less verified conditions.

The new method concerning design POCF has better plants compatibility and less validation conditions.

Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way of using the law in specific circumstances, and shows the variations therein. Sums up that arbitration is much the better way to gok as it avoids delays and expenses, plus the vexation/frustration of normal litigation. Concludes that the US and Greek constitutions and common law tradition in England appear to allow involved parties to choose their own judge, who can thus be an arbitrator. Discusses e‐commerce and speculates on this for the future.

The Bureau of Economics in the Federal Trade Commission has a three-part role in the Agency and the strength of its functions changed over time depending on the preferences and ideology of the FTC’s leaders, developments in the field of economics, and the tenor of the times. The over-riding current role is to provide well considered, unbiased economic advice regarding antitrust and consumer protection law enforcement cases to the legal staff and the Commission. The second role, which long ago was primary, is to provide reports on investigations of various industries to the public and public officials. This role was more recently called research or “policy R&D”. A third role is to advocate for competition and markets both domestically and internationally. As a practical matter, the provision of economic advice to the FTC and to the legal staff has required that the economists wear “two hats,” helping the legal staff investigate cases and provide evidence to support law enforcement cases while also providing advice to the legal bureaus and to the Commission on which cases to pursue (thus providing “a second set of eyes” to evaluate cases). There is sometimes a tension in those functions because building a case is not the same as evaluating a case. Economists and the Bureau of Economics have provided such services to the FTC for over 100 years proving that a sub-organization can survive while playing roles that sometimes conflict. Such a life is not, however, always easy or fun.

The very contextual nature of most mitigating evidence runs counter to America’s individualistic culture. Prior research has found that capital jurors are unreceptive to most mitigating circumstances, but no research has examined the capital sentencing decisions of trial judges. This study fills that gap through a content analysis of eight judicial sentencing opinions from Delaware. The findings indicate that judges typically dismiss contextualizing evidence in their sentencing opinions and instead focus predominately on the defendant’s culpability. This finding calls into question the ability of guided discretion statutes to ensure the consideration of mitigation and limit arbitrariness in the death penalty.

Rural theology is explained here as a form of practical theology that seeks to interpret the rural context in the light of the central themes of Christian theology and vice versa. If Christian theology can be understood as concerning belief in God and the understanding of human relationships with God, the created order, and each other in the light of that belief, rural theology expresses that in the light of the lived experience in a rural context, which for these purposes is the daily bulletin from Ambridge. The author draws on his experience of teaching in the Cambridge Theological Federation to reflect on three recent examples: the recent changes at Brookfield in response to the perennial issue of the milk price lead us to ask who benefits from the production of higher quality food; the care for the land and Adam Macy’s reforms at Home Farm point us to issues about sustainability and responsibility; and the cohesion of a community with shared values and its treatment of Rob Titchener asks questions about the limits of inclusion. As with much practical theology, the outcome of the reflection is in ethical action and some further ethical questions, which, as the example of Jim Lloyd’s philosophical conversations with Alan Franks illustrate, are not the monopoly of the Church.

Database management systems (DBMS) and information retrieval (IR) systems can both be used as online information systems but they differ in the type of data and the types of retrieval they provide for users. Many previous attempts have been made to couple DBMS and IR systems together, either by integrating the two into a unified framework, or by using a DBMS as an implementation tool for information retrieval functionality. This paper reports on some of these previous attempts and describes a system, retriev, which uses a DBMS to implement an IR system for teaching and research purposes. The implementation of retriev is described in detail and the effects that the current trends in database research will have on the relationship between DBMS and IR systems, are discussed.

English Electric has appointed Mr E. B. Lynch as Manager, Aircraft Equipment Sales, responsible for all the products of its Aircraft Equipment Division at Bradford covering aircraft a.c. and d.c. generation, control and protection equipment motors and actuators, and for all the aircraft equipment products of D. Napier & Son Ltd., which are ‘Spraymat’ ice protection system, ‘Sierracote’ heated glass and plastic windscreens and'Sierraglo' electroluminescent lighting equipment.

Black death on a loop online through the click economy brings to bear the mimetic violence associated with Blackness. The idea of consuming Black death as a repeat event highlights the visceral economy of online consumption practices in which Black death is shared and passed on as viral content. The foreshadowing of the Black body and Black death is both banalized and commodified as content for instant gratification spread via algorithms, tagging, likes and newsfeeds. The distributive popular economy online and the offering of Black death through a click economy redrafts Blackness through its historic fungibility of slavery and White oppression, and equally ‘virtuality’ in which both its hyper-visibility and invisibility assemble it through new modalities of violence whilst invoking new spaces to commune, grieve and experience collective grief for these demised bodies. Blackness is made perceptible through its liminality and denial of its corporeality such that both social death and mortal death are ascribed to it. This chapter agitates against the futility of Black death by its quest to read Black humanism online as a moment of empowerment and emancipation to reclaim Blackness and to defy its formlessness in the digital economy as the new graveyard of its spiritual resurrection.