An Analytical Comparison Between Ball and Crossed Roller Bearings for Utilization in Actuator Modules for Precision Modular Robots

2003 ◽  
Author(s):  
Seong-Ho Kang ◽  
Delbert Tesar
Keyword(s):  
High Performance ◽  
Background Information ◽  
Modular Robots ◽  
Extensive Literature ◽  
Positional Accuracy ◽  
Precision Engineering ◽  
Friction Cost ◽  
Low Weight ◽  
Bearing Stiffness ◽  
Robot Configurations

A modular robot system is a collection of actuators, links, and connections that can be arbitrarily assembled into a number of different robot configurations and sequences. High performance modular robots require more than just sophisticated controls. They also need top-quality mechanical components. Bearings in particular must operate well at low speed, have high rotational accuracy, be compact for low weight, and especially be stiff for high positional accuracy. To ensure the successful use of bearings in precision modular robots, knowledge of the bearing properties and requirements are investigated. Background information on various topics such as modular robots, precision modular actuators, and their error sources are described with respect to precision engineering. Extensive literature on thin section bearings is reviewed to examine their use in precision robotic applications. Theoretical studies are performed to calculate bearing stiffness adopting a methodology based on Hertzian theory. This approach is applied to analyze two proposed designs of equivalent-sized crossed roller and four-point bearings, principal bearings used for transmitting all the payload and mass of the robot structure. The maximum deflections and contact stresses for the proposed actuator assembly and loading conditions are estimated and compared including a range of general bearing properties such as friction, cost, and shock resistance.

Analytical Methods Practiced to Quantitation of Rifampicin: A Captious Survey

2020 ◽  
Vol 16 ◽  
Author(s):  
Rajendra Muljibhai Kotadiya ◽  
Foram Narottambhai Patel
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Analytical Methods ◽  
Bacterial Infections ◽  
High Performance ◽  
Drug Product ◽  
Extensive Literature ◽  
Legionnaires Disease ◽  
Instrumental Methods ◽  
Layer Chromatography

Background: Rifampicin (RIF), also known as rifampin, a bactericidal antibiotic having broad antibacterial activity against various gram-positive and gram-negative bacteria act by inhibiting DNA dependent RNA polymerase. RIF has been administered in different dosage forms like tablets, capsules, injections, oral suspension, powder etc. for the treatment of several types of bacterial infections, including tuberculosis, Mycobacterium avium complex, leprosy and Legionnaires’ disease. Introduction: To ensure the quality, efficacy, safety and effectiveness of RIF drug product, effective and reliable analytical methods are utmost important. To quantify RIF for quality control or pharmacokinetic purposes, alternative analytical methods have been developed along with the official compendial methods. Method: In this review paper, an extensive literature survey was done to gather information on various analytical instrumental methods used so far for RIF. Result: These methods were high-performance liquid chromatography (42%), hyphenated techniques (18%), spectroscopy (15%), high-performance thin-layer chromatography or thin-layer chromatography (7%) and miscellaneous (18%). Conclusion: All these methods were selective and specific for the RIF analysis.

Fine Pitch Copper Interconnects for Next Generation Package-on-Package (PoP)

2012 ◽  
Vol 2012 (1) ◽  
pp. 001137-001142 ◽  
Author(s):  
Ilyas Mohammed
Keyword(s):  
High Performance ◽  
Copper Interconnects ◽  
Free Standing ◽  
Positional Accuracy ◽  
Aspect Ratios ◽  
Fine Pitch ◽  
Wire Bonds ◽  
Solder Balls ◽  
The Wire ◽  
Interconnect Technology

For low power processors, stacking memory on top offers many advantages such as high performance due to memory-processor interface within package, small footprint and standard assembly. Package-on-package (PoP) is preferred method of stacking as it offers two discrete packages that are tested separately and can be sourced independently. However, current PoP interconnect technologies do not efficiently scale to meet the memory bandwidth requirements for new generations of multi-core applications processors. The current interconnect technologies such as stacking with smaller sized solder balls, using solder filled laser drilled vias in the mold cap, or using organic interposers are not practically achieving the high IO requirements, since the aspect ratios of these interconnects are limited. To address the gap in PoP interconnect density, a wire bond based package stacking interconnect technology called Bond Via Array (BVA™) is presented that enables reduced pitch and a higher number of interconnects in the PoP perimeter stacking arrangement. The main technological challenges are identified and the research results explained. The three main challenges were forming free standing wire-bonds, molding the package while exposing the tips of the wire-bonds, and package stacking. The assembly results showed that the wire tips were within the desired positional accuracy and height, and the packages were stacked without any loss of yield. These results indicate that the BVA interconnect technology is promising for the very high density and fine pitch required for upcoming mobile computing systems.

Research on High Performance Direct-Driving Motor Applied to Swivel Spindle Head

2014 ◽  
Vol 701-702 ◽  
pp. 874-878
Author(s):  
Shao Hsien Chen ◽  
Chin Mou Hsu ◽  
Kuo Lin Chiu ◽  
Chu Peng Chan
Keyword(s):  
Renewable Energy ◽  
Machine Tool ◽  
Machine Tools ◽  
High Performance ◽  
Cnc Machine Tools ◽  
Cnc Machine ◽  
Positional Accuracy ◽  
Maximum Torque ◽  
Five Axis

Swivel spindle head is a key component used in five-axis machine tool of high performance and is of great importance in application and design. Nowadays, more and more components are manufactured by high performance multi-axis CNC machine tools, such as components of spaceflight, renewable energy and automobile, etc. Therefore, high performance machine tools of multiple axes are more and more urgently demanded, while Swivel spindle head is one of the most important components for a multi-axis machine tool. Hence, Swivel spindle head is one of the key to developers multi-axis machine tool . The study explores the highly responsive direct-driving motor able to drive the spindle head to rotate with multi-driving rotary technology. The dual-driving motor rotates via multi-driving units, generates torsion that magnifies and eliminates its clearance, and then drives the spindle head to rotate. Results of the test show that the completed machine tool can meet the standards of dual axis rotary head with high preformation in, no matter, speed, distance, positional accuracy, repeated accuracy or maximum torque, etc.

scholarly journals Design and Test of Portable Hyperspectral Imaging Spectrometer

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Chunbo Zou ◽  
Jianfeng Yang ◽  
Dengshan Wu ◽  
Qiang Zhao ◽  
Yuquan Gan ◽  
...  
Keyword(s):  
Hyperspectral Imaging ◽  
High Performance ◽  
Small Volume ◽  
High Spatial Resolution ◽  
Flight Test ◽  
High Spectral Resolution ◽  
Imaging Spectrometer ◽  
Low Weight ◽  
Aerial Vehicle ◽  
Small Platform

We design and implement a portable hyperspectral imaging spectrometer, which has high spectral resolution, high spatial resolution, small volume, and low weight. The flight test has been conducted, and the hyperspectral images are acquired successfully. To achieve high performance, small volume, and regular appearance, an improved Dyson structure is designed and used in the hyperspectral imaging spectrometer. The hyperspectral imaging spectrometer is suitable for the small platform such as CubeSat and UAV (unmanned aerial vehicle), and it is also convenient to use for hyperspectral imaging acquiring in the laboratory and the field.

High performance work system, HRD climate and organisational performance: an empirical study

2015 ◽  
Vol 39 (3) ◽  
pp. 239-257 ◽  
Author(s):  
Ashutosh Muduli
Keyword(s):  
Organizational Performance ◽  
Human Resource Development ◽  
High Performance ◽  
Extensive Literature ◽  
Development Environment ◽  
Content Type ◽  
Work System ◽  
High Performance Work System ◽  
The Relationship

Purpose – This paper aims to study the relationship between high-performance work system (HPWS) and organizational performance and to examine the role of human resource development (HRD) Climate in mediating the relationship between HPWS and the organizational performance in the context of the power sector of India. Design/methodology/approach – The empirical research paper has been conceptualized on the basis of extensive literature survey and examined through a case-based approach. Data and information collected to examine strength of the proposed hypothesis in the context of a power-based company in India. Findings – Agreeing with most of the research, HPWS is found to be positively related with organizational performance. The result does not agree with the HPWS research conducted in Asian countries. Taking clues from “Black Box” approach, the role of HRD Climate as a mediating factor has been studied. The result proved that HPWS influences organizational performance through a supportive development environment (HRD climate) based on openness, confrontation, trust, authenticity, proaction, autonomy, collaboration and experimentation (OCTAPAC). Research limitations/implications – Designing and implementing HPWS requires the organization to nurture and develop a suitable HRD climate through development of organizational culture based on OCTAPAC. Practical implications – Implications for HRD–HPWS practices such as group-based pay, decentralized participative decisions, self-managed work teams, social and family events, and appraisal based on team goals along with OCTAPAC culture can significantly contribute to the transfer climate by influencing both peer and supervisor. It can significantly contribute to training motivation by influencing both career and job attitudes, and organizational commitment of trainees. Originality/value – The research is unique in its attempt to understand the role HRD climate as intermediating variables to enhance the effectiveness of HPWS. This may add a lot of value in encouraging organizations to establish HRD Climate.

scholarly journals High Performance Work System and Export Performance

2019 ◽  
Vol 7 (2) ◽  
pp. 245-256
Author(s):  
Ramaisa Aqdas ◽  
Nik Ab Halim Nik Abdullah
Keyword(s):  
Performance Management ◽  
High Performance ◽  
Export Performance ◽  
Extensive Literature ◽  
Four Dimensions ◽  
Work System ◽  
High Performance Work System ◽  
Recruitment And Selection ◽  
The Relationship ◽  
Textile Sector

This paper aims to propose a conceptual framework about the relationship between high performance work system practices and export performance. HPWS is expected to play a crucial role in organizational success. Thus, this paper proposed a framework for studying the relationship among four dimensions of HPWS such as recruitment and selection, performance management, compensation and rewards and training and development and export performance in Pakistan’s textile sector. Moreover, entrepreneurial orientation acts as the mediating factor among these variables. This framework is developed based on extensive literature and this study is expected to contribute towards knowledge by delivering insights and pointing out ways to increase country’s export performance. Specifically, this research will benefit Pakistan’s textile sector in formulating strategies to increase manufacturer’s export performance.

scholarly journals Nanocellulose and nanoclay as reinforcement materials in polymer composites: A review

2020 ◽  
Vol 16 (2) ◽  
pp. 145-153
Author(s):  
Fathin Najihah Nor Mohd Hussin ◽  
Roswanira Abdul Wahab ◽  
Nursyafreena Attan
Keyword(s):  
Mechanical Properties ◽  
Thermal Properties ◽  
Environmental Impact ◽  
Polymer Composites ◽  
Polymer Nanocomposites ◽  
High Performance ◽  
Reinforced Polymer ◽  
Low Weight ◽  
High Performance Polymer ◽  
Strength And Stiffness

The advancement of nanotechnology has opened a new opportunity to develop nanocomposites using nanocellulose (NC) and nanoclay (NCl). Researchers have regarded these nanocomposites as promising substitutes for conventional polymers because of their characteristic and useful features, which include exceptional strength and stiffness, low weight, and low environmental impact. These features of NC and NCl explain their multifarious applications across many sectors. Here we review NC and NCl as well as various reinforced polymer composites that are made up of either of the two nanomaterials. The structural and physicochemical properties of NC and NCl are highlighted, along with the mechanical behavior and thermal properties of NC. Current nanomaterial hybrid biopolymers for the production of novel high-performance polymer nanocomposites are also discussed with respect to their mechanical properties.

scholarly journals Review for Analytical Methods for the Determination of Mefenamic Acid

2021 ◽  
pp. 426-437
Author(s):  
T. V. Ashira ◽  
T. Mohamed Rafeeque ◽  
Saba Maanvizhi ◽  
S. Kathirvel ◽  
P. C. Indukala ◽  
...  
Keyword(s):  
Mefenamic Acid ◽  
Analytical Methods ◽  
High Performance ◽  
Active Pharmaceutical Ingredient ◽  
Review Article ◽  
Computer Assisted ◽  
Extensive Literature ◽  
Pharmaceutical Dosage Forms ◽  
Layer Chromatography

Mefenamic acid (MFA) is a non-steroidal anti-inflammatory drug that belongs to the anthranilic acid derivative family. It is used to relieve mild to moderate pain. The present review article includes a compilation of articles on the various properties along with an extensive literature survey on the reported analytical methods of MFA. Using a comprehensive computer assisted literature review; this article discusses the analytical methodologies for quantifying MFA both in active pharmaceutical ingredient and pharmaceutical dosage forms. This is the first review article in this series with focus on the analytical profile of MFA. Although, several methods like High Performance Liquid Chromatography (HPLC), Thin Layer Chromatography (TLC), spectrophotometry, fluorimetry, turbidimetry, Atomic Absorption Spectroscopy (AAS), Mass Spectroscopy (MS) and electro analytical methods were reported in the literature, HPLC stands out first for the quantification of MFA.

scholarly journals Development and validation of stability indicating HPTLC method for estimation of pirfenidone and characterization of degradation product by using mass spectroscopy

2020 ◽  
Vol 99 (3) ◽  
pp. 51-60
Author(s):  
R. P. Bhole ◽  
◽  
S.R. Jagtap ◽  
C.G. Bonde ◽  
Y.B. Zambare ◽  
...  
Keyword(s):  
Degradation Product ◽  
High Performance ◽  
Degradation Products ◽  
Cost Effective ◽  
Degradation Pathway ◽  
Silica Gels ◽  
Extensive Literature ◽  
Validation Parameters ◽  
Densitometry Analysis ◽  
Hptlc Method

Pirfenidone is used as a novel antifibrotic agent approved for mild-to-moderate idiopathic pulmonary fibrosis. An extensive literature search revealed that, method validation by high-performance thin-layer chromatography (HPTLC) and structural determination by tandem mass spectrometry (MS/MS) method was not reported till date. Precoated silica gels plates were used as a stationary phase. Methanol: ethyl acetate: toluene (1:2:7 v/v) was delivered best separation at 315 nm (Rf 0.49±0.03) by densitometry analysis. Degradation analysis was performed as per ICH guidelines Q2 (R1). Isolation of degradation product was done by the HPTLC method and characterized by using MS/MS method. All the validation parameters were found within the range. Moreover, its possible degradation pathway was also proposed. The Proposed developed and validated HPTLC method was found to be more sensitive, simple, precise, accurate, cost-effective and robust. This method could be applied for the analysis of bulk drug and tablet formulation, degradation study. This degradation pathway of the drug will further help to identify the degradation products of Pirfenidone which may be used for the impurity profiling of the drug.

scholarly journals GraphMineSuite

2021 ◽  
Vol 14 (11) ◽  
pp. 1922-1935
Author(s):  
Maciej Besta ◽  
Zur Vonarburg-Shmaria ◽  
Yannick Schaffner ◽  
Leonardo Schwarz ◽  
Grzegorz Kwasniewski ◽  
...  
Keyword(s):  
Graph Mining ◽  
High Performance ◽  
Maximal Clique ◽  
Building Blocks ◽  
Extensive Literature ◽  
Performance Bounds ◽  
Graph Representations ◽  
Fine Grained ◽  
Performance Metric ◽  
Mining Algorithms

We propose GraphMineSuite (GMS): the first benchmarking suite for graph mining that facilitates evaluating and constructing high-performance graph mining algorithms. First, GMS comes with a benchmark specification based on extensive literature review, prescribing representative problems, algorithms, and datasets. Second, GMS offers a carefully designed software platform for seamless testing of different fine-grained elements of graph mining algorithms, such as graph representations or algorithm subroutines. The platform includes parallel implementations of more than 40 considered baselines, and it facilitates developing complex and fast mining algorithms. High modularity is possible by harnessing set algebra operations such as set intersection and difference, which enables breaking complex graph mining algorithms into simple building blocks that can be separately experimented with. GMS is supported with a broad concurrency analysis for portability in performance insights, and a novel performance metric to assess the throughput of graph mining algorithms, enabling more insightful evaluation. As use cases, we harness GMS to rapidly redesign and accelerate state-of-the-art baselines of core graph mining problems: degeneracy reordering (by >2X), maximal clique listing (by >9×), k -clique listing (by up to 1.1×), and subgraph isomorphism (by 2.5×), also obtaining better theoretical performance bounds.

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