Summary on On-Line Balancing Techniques and Devices of Spindle

2011 ◽  
Vol 287-290 ◽  
pp. 2906-2910 ◽  
Author(s):  
Cai Bo Bai ◽  
Peng Fei Teng ◽  
Rui Ma ◽  
Chang Jing Sun

This paper summarized various adopted widely balancing technology of spindle, specially introduced the principles, structural characteristics, advantages and disadvantages, research and application situations of several on-line balancing devices. Finally, Aiming at the existing problems in the applications of the technologies in spindle dynamic balancing, the article points out the directions in the applications of on-line balance of spindle, and some key problems to be solved in future.

Author(s):  
Zhenhua Li ◽  
Weihui Jiang ◽  
Li Qiu ◽  
Zhenxing Li ◽  
Yanchun Xu

Background: Winding deformation is one of the most common faults in power transformers, which seriously threatens the safe operation of transformers. In order to discover the hidden trouble of transformer in time, it is of great significance to actively carry out the research of transformer winding deformation detection technology. Methods: In this paper, several methods of winding deformation detection with on-line detection prospects are summarized. The principles and characteristics of each method are analyzed, and the advantages and disadvantages of each method as well as the future research directions are expounded. Finally, aiming at the existing problems, the development direction of detection method for winding deformation in the future is prospected. Results: The on-line frequency response analysis method is still immature, and the vibration detection method is still in the theoretical research stage. Conclusion: The ΔV − I1 locus method provides a new direction for on-line detection of transformer winding deformation faults, which has certain application prospects and practical engineering value.


Robotica ◽  
2020 ◽  
Vol 39 (1) ◽  
pp. 55-71 ◽  
Author(s):  
Bin Wei ◽  
Dan Zhang

SUMMARYThe authors summarize the main dynamic balancing methods of robotic mechanisms in this paper. The majority of dynamic balancing methods have been presented, and there may be other dynamic balancing methods that are not included in this paper. Each of the balancing methods is reviewed and discussed. The advantages and disadvantages of each method are presented and compared. The goal of this paper is to provide an overview of recent research in balancing. The authors hope that this study can provide an informative reference for future research in the direction of dynamic balancing of robotic mechanisms.


2020 ◽  
Vol 39 (1) ◽  
pp. 247-259
Author(s):  
Liu Yang ◽  
Molin Qin ◽  
Junchao Yang ◽  
Genwei Zhang ◽  
Jiana Wei

Abstract Gas chromatography (GC) is an important and widely used technique for separation and analysis in the field of analytical chemistry. Micro gas chromatography has been developed in response to the requirement for on-line analysis and on-site analysis. At the core of micro gas chromatography, microelectromechanical systems (MEMs) have the advantages of small size and low power consumption. This article introduces the stationary phases of micro columns in recent years, including polymer, carbon materials, silica, gold nanoparticles, inorganic adsorbents and ionic liquids. Preparation techniques ranging from classical coating to unusual sputtering of stationary phases are reviewed. The advantages and disadvantages of different preparation methods are analyzed. The paper introduces the separation characteristics and application progress of MEMs columns and discusses possible developments.


2021 ◽  
Vol 97 (4) ◽  
pp. 72-81
Author(s):  
M. S. Syupova ◽  

Ensuring the economic security of municipalities is one of the key conditions for stable socio-economic de-velopment of the region. Recently, intraregional differentiation of territories has been growing, which increases the risk of the formation of negative factors that reduce the quality of life of the population. In order to neutralize and prevent acute social and economic problems, constant monitoring of the current state of the municipal econ-omy is necessary. As such a management tool, a rating assessment of the economic security of municipalities in the region can be used. The ranking of territories allows you to visualize the relative advantages and disadvantages of the development of territories. In addition, a systematic comparative analysis of controlled socio-economic pa-rameters will allow regional authorities to evaluate the results of the activities of local governments and improve the effectiveness of regional socio-economic policy. The article proposes a methodology for rating the economic security of municipalities, during which it is possible to visually assess the depth of the threats studied at the level of each territory. To this end, the proposed methodology is based on a system of indicators that identify the main problem areas of the socio-economic condition of the territories. To form the rating, the studied indicators are normalized and integral indices characterizing the level of economic security of municipalities are calculated. The methodology proposes criteria for assessing the level of municipal economic security (high; above average; aver-age; crisis; critical). According to the results of the study, a rating of municipal districts of the Khabarovsk Terri-tory was compiled. The study showed that the territories of the region are characterized by an unstable socio-economic condition. The leading positions in the rating are occupied by areas with an average level of economic security. Most municipal districts of the region have a crisis level of economic security, which provides for the de-velopment of a set of measures aimed at eliminating existing problems.


Author(s):  
Huaiqiang Zhang ◽  
Qiang Xue ◽  
Shuo Yang ◽  
Tongtong Wang ◽  
Binwei Zhou

Background: Completing the transition from a sitting position to a standing position is a basic skill in people’s daily lives and is crucial for independent living. Lower limb dysfunction will bring many inconveniences into a person’s life and greatly affect their quality of life. Patients with lower limb dysfunction are a specialized group, and nursing problems for this group are becoming increasingly serious. Helping patients with lower limb dysfunction restore their lower limb mobility or assisting them to walk is a social problem necessary to be solved. Objective: : To review the recent sit-to-stand assistive devices based on hip support, classify them systematically and introduce their characteristics, including the mechanisms and the types of patients for which such mechanisms are applicable; to help patients with lower limb dysfunction or doctors (therapists) understand and choose a reasonable sit-to-stand assist device based on hip support. Methods: This paper summarizes literatures and patents about sit-to-stand assistive devices. From the aspects of structural characteristics, drive type and support modes based on the hip and applications situation, the advantages and disadvantages of the typical sit-to-stand assist devices are represented. Results: Current and future development trends on the structural characteristics, drive type and support modes based on the hip and applications situation of sit-to-stand assist devices are discussed to improve the humanization, modularization and applicability of sit-to-stand assist devices. Conclusion: Sit-to-stand assistive devices based on hip support can help patients improve the quality of their life, assist patients carrying out rehabilitation training, and delay the decline of lower limb function. However, the existing sit-to-stand assistive devices based on hip support need further improvement in the aspects of motion mechanism, new technology application and ergonomics design.


2018 ◽  
Vol 232 ◽  
pp. 04078
Author(s):  
Min Zhang ◽  
Jun-Bin Liang

Mobile wireless sensor networks (MWSN) are composed of a large number of mobile sensor nodes, which are used to collect data. MWSN have been widely applied in a variety of harsh environments, so mobile sensor nodes are often at risk of damage. How to manage mobile sensor nodes is an important issue. In this paper, we analyse different mobility management schemes proposed in some typical research literature and classify these schemes by using three features: the collaboration between mobile sensor nodes, routing and deployment in MWSN. We specify advantages and disadvantages of the proposed schemes, compare different key parameters of MSWN respectively, including energy efficiency, data delay, cost and lifetime, etc. Finally, we discuss existing problems of MWSN management and give some helpful suggestions in this area.


2016 ◽  
Vol 15 (2) ◽  
pp. 182
Author(s):  
SAIFUL .. ◽  
MULYADI HAMBALI ◽  
TRI MUHADI RAHMAN

PT XYZ merupakan salah satu perusahaan yang bergerak di bidang industri mebel. Masalah yang dihadapi perusahaan adalah adanya ketidakseimbangan di lintasan produksi akibat ketidakmerataan pembagian beban kerja di setiap stasiun kerja. Hal ini menyebabkan performansi keseimbangan lintasan (line performance) menjadi kurang baik. Untuk menyelesaikan permasalahan ini perlu dilakukan penyeimbangan lintasan produksi. Hal ini dapat dilakukan dengan metode line balancing yaitu metode penugasan sejumlah pekerjaan yang saling berkaitan dalam satu lintasan produksi sehingga setiap stasiun kerja memiliki waktu yang tidak melebihi waktu siklus dari stasiun kerja tersebut. Metode line balancing yang digunakan adalah metode heuristik yang terdiri dari: metode bobot posisi (Ranked Positional Weight), metode pembebanan berurut (Large Candidate Rule), dan metode pendekatan wilayah (Region Approach). Dari ketiga metode Heuristik yang digunakan sebagai solusi penyeimbangan lintasan, terjadi perbaikan performansi dengan nilai yang sama pada lintasan produksi. Nilai efisiensi lintasan (line efficiency) meningkat menjadi 94,07 % dari 62,71 % pada kondisi awal. Nilai keseimbangan waktu senggang (balance delay) turun menjadi 5,92 % dari 37,28 % pada kondisi awal. Waktu menganggur (idle time) turun menjadi 12,39 menit dari 116,87 menit pada kondisi awal. Nilai smoothness index juga turun menjadi 7,44 dari 64,67 pada kondisi awal. PT XYZ is one of the company which refers to furniture industries sector. The problem which faced by this company is unbalance of the production line which is caused by the unequal of work responsibility distribution in each work station. This problem caused the performance of line balance doesn’t work properly. To solve this problem we need to do the line balancing of production line. It can be done by line balancing methode that assigns a number of work which is related in one production line until each work station has efficient time which is not more than the cycle time of the work station. Line balancing methode that used is heuristic methode which is devided into ranked positional weight methode, large candidate rule methode, and region approach methode. From those three heuristic methode that used as solution of line balancing, there was improvement happenned with the same value in doors of production line. Line efficiency increased into 94,07% from 62,71% at the beginning condition. Balance delay increased into 5,92% from 37,28% at the beginning condition. The idle time descreased into 12,39 minutes from 116,87 minutes at the beginning condition. The smoothness index descreased into 7,44 from 64,67 at the beginning condition.


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