Kinematic and dynamic analysis of a serial manipulator with local closed loop mechanisms

This paper addresses the kinematic and dynamic modelling and analysis for a robot arm consisting of two hydraulic cylinders driving two revolute joints of the arm. The two cylinders and relevant links of the robot constitute two local closed kinematic chains added to the main robot mechanism. Therefore, the number of the generalized coordinates of the mechanical system is increased, and the mathematical modelling is more complex that requires a formulation of constraint equations with respect to the local closed chains. By using the Lagrangian formulation with Lagrangian Multipliers, the dynamic equations are first derived with respect to all extended generalized coordinates. Then a compact form of the dynamic equations is yielded by canceling the Multipliers. Since the obtained dynamic equations are expressed in terms of independent generalized coordinates which are selected according to active joint variables of the arm, the equations could be best suitable for control law design and implementation. The simulation of the forward and inverse kinematics and dynamics of the arm demonstrates the motion behavior of the robot system

Benchmarking and smart control in Finnish sewerage pumping stations

Sewerage system avoids flood and pollutants being discharged into the environment, which presents considerable economic, social, and environmental impacts. Due to the worldwide energy crisis and climate change from urbanization, the current network capacity and control will not be sufficient. Hence, we need better control for the pumping stations to satisfy future requirements. The goal of the work is to create an overall picture of the current Finnish sewerage systems and evaluate the effectiveness and applicability of smart control in reducing energy consumption and flooding. The study was conducted in two phases: benchmarking and smart control solutions. In the first phase, the performance of the wastewater system in general and pumping stations specifically in five water utilities (HS-Vesi Oy, Porvoon Vesi, Kurikkan Vesihuolto Oy, Kouvola Vesi, and Tuusulan Vesi) was analyzed with their hydraulic performance and flood-risk assessment, therefore pointing out the opportunities for improvement. Following this, several pumping station chains were selected for applying smart control. The second phase was to develop a suitable wet well’s level control algorithm based on two principles: variable speed drive and feedback PID controller. The results indicated that the infiltration rate of the Finnish sewerage network was on an average level and the energy efficiency was on a fair to poor level, according to studies from other countries and based on the assessment standards. Yet, there is an opportunity to apply energy-recover equipment in the future. When comparing the five studied sites, Kurikka and Porvoo had lower infiltration rates, while Kouvola and Hämeenlinna had higher energy efficiency. The proposed level control worked at its best during conditions that have high total inflows, in combination with more suitable pump selections. More thorough research should be done in the future on the energy-saving potential of using variable speed drives in combination with level control. The level control performance in overflow reduction was restricted to a definite level based on the network capacity. When the total network capacity has been utilized, additional storage is suggested to store the overflows

Outcome measures of chronic arthritis in Hong Kong: comparison of the AIMS2 (Chinese) and WHO quality of life - brief form (WHOQOL-BREF) (HK)

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Inverse kinematics of a serial-parallel robot used in hot forging process

In hot extrusion forging process, the use of  robot arm for transferring heavy billets can reduce downtime, improve  productivity, reduce worker fatigue and optimize the use of~energy and  manpower. To increase the stiffness of the robot and force the end-effector  move in directions parallel with the ground surface, two parallel links are  added to a standard serial manipulator. This modification of the structure  could make it a bit of challenge in the system modelling and controlling.  This paper addresses the inverse kinematics analysis that is the central  issue for developing autonomous control modes of the robot application

THE FORMATION OF FACEBOOK STICKINESS: THE PERSPECTIVES OF MEDIA RICHNESS THEORY, USE & GRATIFICATION THEORY AND INTIMACY

With the advent of web 2.0, social networking sites (SNSs) have mushroomed. Gaining competitive advantage by retaining users in the SNS is an important issue for operators. By conceptualizing stickiness as the state of individuals’ prolong stay on the SNS, the aim of this study is to explore the process of formatting SNS stickiness in the context of Facebook from the perspectives of media richness theory, uses & gratifications (U & G) theory, and intimacy. Data was collected from the northern Taiwan University. A total of 187 questionnaires were selected for the data analysis. The results support the following conclusions: 1) the media richness provided by the Facebook website directly influences users’ gratifications, including interpersonal utility and social utility; 2) the intimacy is an important mediating variable involving in the process of formatting Facebook stickiness; and 3) Facebook stickiness is indirectly influenced by gratifications, interpersonal utility and social utility, which exerts its effect through intimacy. By integrating the theoretical perspectives of media richness theory, U & G theory with intimacy into the process model of formatting Facebook stickiness, this study provides both academics and practitioners with insight into how Facebook stickiness form and enable SNS manager to retain their users

Adaptation options for agricultural cultivation systems in the South Central Coast under the context of climate change: Assessment Report.

This report highlights the results of consultation meetings and field visits organized by the Department of Crop Production and the CGIAR Research Program on Climate Change, Agriculture and Food Security in Southeast Asia in association with the three offices of the Department of Agriculture and Rural Development in the South Central Coast provinces of Binh Thuan, Ninh Thuan, and Khanh Hoa, in combination with consultation with the provinces in the conference: “Summing up crops production in the Winter-Spring season in 2018-2019, implementing the Summer-Autumn season, Main rice season in 2019 for the South Central Coast and the Central Highlands” held by the Ministry of Agriculture and Rural Development in Tam Ky City, Quang Nam Province on 12 April 2019. The meetings underlined the progress made by the provinces on climate change adaptation and mitigation, options for risk reductions in agricultural production, and conversion of crop structure as results of implementing the guidelines of the provinces and the Sector, especially, solutions for reservation and efficient and economic use of water under the context of climate change. This assessment report also reviews some issues related to the agricultural transformation of the region in adapting to risks caused by climate change. They are based on comparative advantages in terms of geographical location and market of key agricultural products. This report also points out shortcomings in using land and unreasonable points in managing and using important natural resources, especially water, and provides recommendations for the agricultural transformation and inter-regional connection with the Central Highlands and the Southeast. The team also introduces climate-related risks maps and adaptation plans (CS MAP) which is applied in the five provinces in the Mekong Delta Region, and hopes this solution’s expansion shall be supported by the Ministry of Agriculture and Rural Development and the provinces

An efficient finite element formulation of dynamics for a flexible robot with different type of joints

If two adjacent links of a flexible robot are connected via a revolute joint or a fixed prismatic joint, the relative motion of the next link will depend on both the joint motion and the elastic displacement of the distal end of the previous link. However, if the two adjacent links are connected via a sliding prismatic joint, the relative motion of the next link will depend additionally on the elastic deformation distributed along the previous link. Therefore, formulation of the motion equations for a multi-link flexible robot consisting of the revolute joints, the fixed prismatic joints and the sliding prismatic joints is challenging. In this study, the finite element kinematic and dynamic formulation was successfully developed and validated for the flexible robot, in which a transformation matrix is proposed to describe the kinematics of both the joint motion and the link deformation. Additionally, a new recursive formulation of the dynamic equations is introduced. As compared with the previous methods, the time complexity of the formulation is reduced by O(2η), where η is the number of finite elements on all links. The numerical examples and experiments were implemented to validate the proposed kinematic and dynamic modelling method

Efficacy and Toxicity of Folfoxiri for Patients with Metastatic Colorectal Cancer

BACKGROUND: In recent times, scientists have found new treatments for colorectal cancer patients. AIM: The study is to evaluate the efficacy and toxicity of triplet combination chemotherapy of 5-fluorouracil/leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI) for patients with metastatic colorectal cancer in stage IV. METHODS: Uncontrolled clinical trial carried on 39 stage IV colorectal cancer patients. RESULTS: The overall response rate of the treatment was 79.4%. The average progression-free survival was 13.4 ± 9 months. The overall survival rate at 12th month and 24th month were 90% and 76%, respectively. The proportion of granulocytopenia was 48.9%, no grade 3 or 4. Side effect beyond hematology was most seen in hepatic toxicity with 52.5%, mainly at grade 1. Vomiting was 18.3%, all at grade 1. Other adverse event was very low at percentage. CONCLUSIONS: The triplet combination FOLFOXIRI chemotherapy improves the outcome of patients with metastatic colorectal cancer regarding rate of response, overall survival rate and progression-free survival, and the level of toxicity was acceptable

Generalized pseudo inverse kinematics at singularities for developing five-axes CNC machine tool postprocessor

This paper presents an analytical scheme for analyzing the singular configuration problem of general five-axes CNC machine tool. A computational technique based on the generalized pseudo inverse kinematics for finding out feasible solution of the problem is proposed. The technique is then used for developing post processor algorithm of five-axes CNC machine tool. Typical examples of singularity analysis are carried out, and real cutting parts are implemented for verifying the research result