A framework for the integration of green and lean six sigma for superior sustainability performance

Evidence suggests that Lean, Six Sigma and Green approaches make a positive contribution to the economic, social and environmental (i.e. sustainability) performance of organizations. However, evidence also suggests that organizations have found their integration and implementation challenging. The purpose of this research is therefore to present a framework that methodically guides companies through a five stages and sixteen steps process to effectively integrate and implement the Green, Lean and Six Sigma approaches to improve their sustainability performance. To achieve this, a critical review of the existing literature in the subject area was conducted to build a research gap, and subsequently develop the methodological framework proposed. The paper presents the results from the application of the proposed framework in four organizations with different sizes and operating in a diverse range of industries. The results showed that the integration of Lean Six Sigma and Green helped the organizations to averagely reduce their resources consumption from 20% to 40% and minimize the cost of energy and mass streams by 7-12%. The application of the framework should be gradual, the companies should assess their weaknesses and strengths, set priorities, and identify goals for successful implementation. This paper is one of the very first researches that presents a framework to integrate Green and Lean Six Sigma at a factory level, and hence offers the potential to be expanded to multiple factories or even supply chains

α-Adducin Gly460Trp Gene Mutation and Essential Hypertension in a Chinese Population: A Meta-Analysis including 10960 Subjects

BACKGROUND: The α-adducin Gly460Trp (G460W) gene polymorphism may be associated with susceptibility to essential hypertension (EH), but this relationship remains controversial. In an attempt to resolve this issue, we conducted a meta-analysis. METHODS: Twenty-three separated studies involving 5939 EH patients and 5021 controls were retrieved and analyzed. Four ethnicities were included: Han, Kazakh, Mongolian, and She. Eighteen studies with 5087 EH patients and 4183 controls were included in the Han subgroup. Three studies with 636 EH patients and 462 controls were included in the Kazakh subgroup. The Mongolian subgroup was represented by only one study with 100 EH patients and 50 controls; similarly, only one study with 116 EH patients and 326 controls was available for the She subgroup. The pooled and ethnic group odds ratios (ORs) along with the corresponding 95% confidence intervals (95% CI) were assessed using a random effects model. RESULTS: There was a significant association between the α-adducin G460W gene polymorphism and EH in the pooled Chinese population under both an allelic genetic model (OR: 1.12, 95% CI: 1.04-1.20, P = 0.002) and a recessive genetic model (OR: 1.40, 95% CI: 1.16-1.70, P = 0.0005). In contrast, no significant association between the α-adducin G460W gene polymorphism and EH was observed in the dominant genetic model (OR: 0.88, 95% CI: 0.72-1.09, P = 0.24). In stratified analysis by ethnicity, significantly increased risk was detected in the Han subgroup under an allelic genetic model (OR: 1.13, 95% CI: 1.04-1.23, P = 0.003) and a recessive genetic model (OR: 1.43, 95% CI: 1.17-1.75, P = 0.0006). CONCLUSIONS: In a Chinese population of mixed ethnicity, the α-adducin G460W gene polymorphism was linked to EH susceptibility, most strongly in Han Chinese

TelePhysicalOperation: Remote Robot Control Based on a Virtual "Marionette" Type Interaction Interface

open4noTeleoperation permits to control robots from a safe distance while performing tasks in a remote environment. Kinematic differences between the input device and the remotely controlled manipulator or the existence of redundancy in the remote robot may pose challenges in moving intuitively the remote robot as desired by the human operator. Motivated by the above challenges, this work introduces TelePhysicalOperation, a novel teloperation concept, which relies on a virtual physical interaction interface between the human operator and the remote robot in a manner that is equivalent to a "Marionette" based interaction interface. With the proposed approach, the user can virtually "interact" with the remote robot, through the application of virtual forces, which are generated by the operator tracking system and can be then selectively applied to any body part of the remote robot along its kinematic chain. This leads to the remote robot generating motions that comply with the applied virtual forces, thanks to the underlying control architecture. The proposed method permits to command the robot from a distance by exploring the intuitiveness of the "Marionette" based physical interaction with the robot in a virtual/remote manner. The details of the proposed approach are introduced and its effectiveness is demonstrated through a number of experimental trials executed on the CENTAURO, a hybrid leg-wheel platform with an anthropomorphic upper body.openTorielli D.; Muratore L.; Laurenzi A.; Tsagarakis N.Torielli, D.; Muratore, L.; Laurenzi, A.; Tsagarakis, N

Towards an Open-Source Hardware Agnostic Framework for Robotic End-Effectors Control

none4noNowadays a wide range of industrial grippers are available on the market and usually their integration to robotics automation systems relies on dedicated software modules and interfaces specific for each gripper. During the past two decades, more sophisticated end-effector modules that target to provide additional functionality including dexterous manipulation skills as well as sensing capabilities have been developed. The integration of these new devices is usually not trivial, requiring the development of brand new, tailor-made software modules and interfaces, which is a time consuming and certainly not efficient activity. To address the above issue and facilitate the quick integration and validation of the new end-effectors, we developed the ROS End-Effector open-source framework, which provides a software infrastructure capable to accommodate a range of robotic end-effectors of different hardware characteristics (number of fingers, actuators, sensing modules and communication protocols) and capabilities (with different manipulation skills, such as grasping, pinching, or independent finger dexterity) effectively facilitating their integration through the development of hardware agnostic software modules, simulation tools and application programming interfaces (APIs). A key feature of the ROS End-Effector framework is that rather than controlling each end-effector in a different and customized way, following specific protocols and instructions data fields, it masks the physical hardware differences and limitations (e.g., kinematics and dynamic model, actuator, sensor, update frequency, etc.) and permits to command the end-effector using a set of high level grasping primitives. The framework capabilities and flexibility in supporting different robotics end-effectors are demonstrated both in a kinematic/dynamic simulation and in real hardware experiments.openTorielli D.; Bertoni L.; Tsagarakis N.; Muratore L.Torielli, D.; Bertoni, L.; Tsagarakis, N.; Muratore, L

A Shared Telemanipulation Interface to Facilitate Bimanual Grasping and Transportation of Objects of Unknown Mass

The teleoperation of robots with human-like capabilities may pose significant challenges to the human operator due to the kinematic complexity and redundancy of these robots. Bimanual telemanipulation represents such a challenging task that requires precise coordination of the two arms to perform a stable bimanual grasp on an object and eventually transport the object while maintaining the grasp.In this work, we present a shared control telemanipulation interface to facilitate the bimanual grasping and transportation of objects of unknown mass. With the proposed method, the robot is able to transport the object maintaining autonomously a sufficient amount of grasping force while accepting commands from the operator to reach the desired location. As humans do, it is not necessary to know the weight of the object in advance; instead, the robot estimates it during the lifting phase. On the basis of the estimated weight, the required amount of grasping force is computed. During object transportation, the robot autonomously regulates the grasping forces in a shared control fashion, allowing the operator to seamlessly command only the trajectories of the object.The proposed method has been implemented and validated on the CENTAURO robot, a quadrupedal platform with a humanoid dual arm upper body, performing experiment where objects of different weights and dimensions must be picked up and transported

Towards a Generic Grasp Planning Pipeline using End-Effector Specific Primitive Grasping Actions

In the past few years, several robotic end-effectors based on diverse kinematics and actuation principles have been developed to provide grasping and manipulation functionalities. To ease the control and application of these wide-ranging end-effectors, the development of effective reusable tools that can facilitate the end-effector motion planning and control is necessary. In this work, we introduce a generic grasp planner that leverages on the concept of the primitive grasping actions. Given the specific characteristics of an end-effector, including its kinematic and actuation arrangements, a number of primitive grasping actions are extracted and employed by the proposed grasp planner to autonomously plan and synthesize more complex grasping behaviours. The grasp planner is validated through experimental trials involving the HERI II robotic hand, a four-fingers tendon-driven under-actuated hand. The results of these experiments demonstrate the efficacy of the proposed method to generate appropriate planning actions enabling to grasp objects of different shapes

On the pathogenetic mechanism of hypercalciuria in genetically hypertensive rats of the Milan strain

The aim of this study was to investigate the pathogenesis of hypercalciuria in the Milan strain of genetically hypertensive rats. Dietary calcium intake and urinary and fecal calcium output were measured simultaneously with indices of sodium and phosphate homeostasis in male rats of the Milan hypertensive and normotensive strains. In addition, urinary calcium and creatinine excretion rates, calcium, phosphate and creatinine serum concentrations, and bone calcium content were also measured in these rats after an overnight fast. Under fed steady-state conditions dietary calcium, sodium, and phosphate intakes, were similar in the two groups of rats, but hypertensive rats had twofold higher urinary calcium excretion and normal urinary excretion of sodium and phosphate. Fecal calcium output was slightly but significantly higher in the adult hypertensive rats while fecal sodium and phosphate excretion was normal. Because of increased urinary and fecal calcium loss, net calcium balance was significantly less positive in hypertensive than in control rats. Under fasting conditions hypertensive rats were confirmed to have hypercalciuria despite normal serum calcium concentrations and normal creatinine clearance. In accordance with balance data and fasting hypercalciuria, bone calcium content was found to be significantly reduced in hypertensive rats. These findings confirm that hypercalciuria in the Milan hypertensive rats is explained by an altered renal calcium handling; it is also associated with a slightly increased fecal calcium output and, therefore, with a less positive calcium balance and reduced bone calcium content