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Since 1996, the Bank for International Setdements (BIS) has set the capital level that banks must hold against market risks by a specific formula. This article presents a practical approach for incorporating the effects of asset illiquidity and management response lags in setting regulatory capital levels to account for market risk. According to the BIS guidelines, capital should be a function of the effectiveness of limit management and market liquidity, because actively managing limits and positions can significantly reduce the risk of a trading operation. Although this approach represents an improvement over previous methods of setting capital, significant limitations still remain, namely, liquidity constraints and response lags in management intervention, which increase portfolio risk. The authors suggest specific amendments to the reg‐ulatory capital guidelines that may mitigate both of these limitations

The coupling impact of hybrid uncertain errors on the machine precision is complex, as a result of which the designing method with multiple independent error sources under uncertainties remains a challenge. For the purpose of precision improvement, this paper focuses on the robot design and aims to present an assembly precision design method based on uncertain hybrid tolerance allocation (UHTA), to improve the positioning precision of the mechanized robot, as well as realize high precision positioning within the workspace.

The fundamentals of the parallel mechanism are introduced first to implement concept design of a 3-R(4S) &3-SS parallel robot. The kinematic modeling of the robot is carried out, and the performance indexes of the robot are calculated via Jacobian matrix, on the basis of which, the 3D spatial overall workspace can be quantified and visualized, under the constraints of limited rod, to avoid the singular position. The error of the robot is described, and a probabilistic error model is hereby developed to classify the hybrid error sensitivity of each independent uncertain error source by Monte Carlo stochastic method. Most innovatively, a methodology called UHTA is proposed to optimize the robot precision, and the tolerance allocation approach is conducted to reduce the overall error amplitude and improve the robotized positioning precision, on the premise of not increasing assembly cost.

The proposed approach is validated by digital simulation of medical puncture robot. The experiment highlights the mathematical findings that the horizontal plane positioning error of the parallel robotic mechanism can be effectively reduced after using UHTA, and the average precision can be improved by up to 39.54%.

The originality lies in UHTA-based precision design method for parallel robots. The proposed method has widely expanding application scenarios in industrial robots, biomedical robots and other assembly automation fields.

This paper utilizes the improved particle swarm optimization (IPSO) with bounded constraints technique on velocity and positioning for adjusting the gains of a proportional-integral-derivative (PID) and iterative learning control (ILC) controllers. The purpose of this paper is to achieve precision motion through bettering control by this technique.

Actual platform positioning must avoid the occurrence of a large control action signal, undesirable overshooting, and preventing out of the maximum position limit. Several in-house experiments observation, the PSO mechanism is sometimes out of the optimal solution in updating velocity and updating position of particles, the system may become unstable in real-time applications. The proposed IPSO with new bounded constraints technique shows a great ability to stabilize nonminimum phase and heavily oscillatory systems based on new bounded constraints on velocity and positioning in PSO algorithm is evaluated on one axis of linear synchronous motor with a PC-based real-time ILC.

Simulations and experiment results show that the proposed controller can reduce the error significantly after two learning iterations. The developed method using bounded constraints technique provides valuable programming tools to practicing engineers.

The proposed IPSO-ILC-PID controller overcomes the shortcomings of conventional ILC-PID controller with fixed gains. Simulation and experimental results show that the proposed IPSO-ILC-PID algorithm exhibits great speed convergence and robustness. Experimental results confirm that the proposed IPSO-ILC-PID algorithm is effective and achieves better control in real-time precision positioning.

In October of 1987 stock market prices all over the world fell by staggering amounts. A financial panic spreading beyond stock markets did not occur and it would appear that any real economic consequences of the crash have, thus far, been small. A superficial reading of economic history suggests that things might have turned out a whole lot worse. It is this thought that makes an evaluation of various restrictions designed to limit stock market volatility ‐ so called circuit breakers ‐ timely.

The purpose of this paper is to implement a glass-curtain-wall cleaning robot driven by a double flexible rope, so as to replace manual cleaning. The glass-curtain-wall, because of its excellent daylighting performance, damp-proofing characteristics, heat insulation properties and aesthetics, is widely used in modern city buildings. For glass-curtain-wall buildings, regular cleaning of the glass-curtain-wall is necessary to ensure that the surface of the building appears clean and tidy, which in turn contributes toward preserving the overall aesthetic appearance of the city. Currently, the primary method of cleaning glass curtain walls is manual cleaning by workers on a suspended platform.

The mechanical structure of the proposed glass-curtain-wall cleaning robot driven by a double flexible rope is inspired by the way a spider moves by pulling its silk draglines in the air. For self-locking protection and increased rope friction, the robot’s moving section includes a worm reducer and multislot master–slave roller. The cleaning section comprises a water tank, control valve, shower nozzle and brush. The wall adsorbing section is realized by a double rotor. The workspace of the robot is analyzed. Flexible rope winding and unreeling control of the cleaning robot is deduced. The force of the cleaning robot when the double rotor is working is analyzed and calculated. The prototype of the glass-curtain-wall cleaning robot model driven by a double flexible rope is established, and experiments wherein the robot moves along a preset track, as well as cleaning experiments, are performed.

The prototype of the glass-curtain-wall cleaning robot model driven by a double flexible rope can move along the preset track, satisfy the design functions and clean effectively. The experimental results verify the validity and practicality of the robot.

The implication of this research is that a glass-curtain-wall cleaning robot model driven by a double flexible rope fulfills the movement strategy and drive-type requirements for cleaning glass curtain walls. The limitation of this research is that it is difficult to implement rapid cleaning.

The traditional method of manual cleaning by workers on a suspended platform will be changed after the glass-curtain-wall cleaning robot is manufactured, and the advent of this cleaning robot for the low- and mid-rise buildings will reduce the cost of cleaning buildings, improve the working environment and enhance production efficiency.

The aim of this paper is to implement direct teaching of industrial manipulators using current sensors. The traditional way to implement teaching is either to use a teaching pedant, which is time consuming, or use force sensors, which increases system cost. To overcome these disadvantages, a novel method is explored in the paper by using current sensors installed at joints as torque observers.

The method uses current sensors installed at each joint of a manipulator as torque observers and estimates external forces from differences between joint-driven torque computed based on the values of current sensors and commanded values of motor-driven torque. The joint-driven torque is computed by cancelling out both pre-calibrated gravity and friction resistance (compensation). Also, to make the method robust, the paper presents a strategy to detect unexpected slowly drifts and zero external forces and stop the robot in those situations.

Experimental results demonstrated that compensating the joint torques using both pre-calibrated gravity and friction resistance has performance comparable to a force sensor installed on the end effector of a manipulator. It is possible to implement satisfying direct teaching without using force sensors on 7 degree of freedom manipulators with large mass and friction resistance.

The main contribution of the paper is that the authors cancel out both pre-calibrated gravity and friction resistance to improve the direct teaching using only current sensors; they develop methods to avoid unsafe situations like slow drifts. The method will benefit industrial manipulators, especially those with large mass and friction resistance, to realize flexible and reliable direct teaching.

Before designing a navigation system, it is necessary to analyse possible approaches in terms of expected accuracy, existing limitations and economic justification to select the most advantageous solution. This paper aims to collect possible navigation methods that can provide correction for inertial navigation and to evaluate their suitability for use on a manoeuvring tactical missile.

The review of existing munitions was based on data collected from the literature and online databases. The data collected included dimensions, performance, applied navigation and guidance methods and their achievable accuracy. The requirements and limitations identified were confronted with the range of sensor parameters available on the market. Based on recent literature, navigation methods were reviewed and evaluated for applicability to inertial navigation system (INS) correction in global navigation satellite system-denied space.

The performance analysis of existing munition shows that small and relatively inexpensive micro-electro-mechanical system-type inertial sensors are required. A review of the parameters of existing devices of this type has shown that they are subject to measurement errors that do not allow them to achieve the delivery accuracy expected of precision missiles. The most promising navigation correction methods for manoeuvring flying objects have been identified.

The information presented in this paper is the result of the first phase of a project and presents the results of the requirements selection, initial sizing and preliminary design of the navigation system. This paper combines a review of the current state of the art in missile systems and an analysis of INS accuracy including the selection of sensor parameters.

The purpose of this paper is to use the redundancy of a new hybrid automatic fastening system (HAFS) for aircraft assembly in the best way.

First, the kinematic model of HAFS is divided into three sub-models, which are the upper/lower tool and parallel robot. With the geometric coordination relationship, a comprehensive kinematic model of the HAFS is built by mathematically assembling the sub-models based on the DH method. Then, a novel master-slave decoupling strategy for inverse kinematics solution is proposed. With the combination of the minimum energy consumption and the comfortable configuration, a multi-objective redundancy resolution method is developed to optimize the fastening configuration of the HAFS, which keep the HAFS away from the joint-limits and collision avoiding in the aircraft panel assembly process.

An efficient multi-objective posture optimization algorithm to use the redundancy in the best way is obtained. Simulation and an experiment are used to demonstrate the correctness of the proposed method. Moreover, the position and orientation errors of the drilling holes are within 0.222 mm and 0.356°, which are accurate enough for the automatic fastening in aircraft manufacturing.

This method has been used in the HAFS control system, and the practical results show the aircraft components can be fastened automatically through this method with high efficiency and high quality.

This paper proposes a comprehensive kinematic model and a novel decoupling strategy for inverse kinematic solution of the HAFS, which provides a reference to utilize the redundancy in the best way for a hybrid machine with redundant function.