Combined Manufacturing Process of Electrochemical-Etching and Electroplating on Nanoporous Silicon for its Metallization

In this work, a combined process for simultaneously manufacturing nanoporous silicon (NPS) and its metallization was present. The key point is the utilization of adjust electrolyte of silver nitrate and the electroplating timing after the NPS etching process. The current-control mode was used to prepare NPS membrane and the obtained pore-size and pillar-depth were about 0.5 μm and 140 μm, respectively. For clarify the metallization quality of studied process, the semiconductor analyzer was utilized to measured current-voltage (IV) characteristic. Compared to NPS with conventional electroplating process, the contact properties of fabricated sample would be effectively improved by the proposed method. The obtained IV characteristic of sample with combined process shows a larger turn-on current about 277 times than other samples.

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Application Of Cusum Chart In Control Of Paper Quality

GIS Business ◽

10.26643/gis.v14i6.16856 ◽

2020 ◽

Vol 14 (6) ◽

pp. 1062-1069

Author(s):

S.Ramesh ◽

B.A.Vasu

Keyword(s):

Process Parameters ◽

Manufacturing Process ◽

Paper Industry ◽

Primary Data ◽

Cusum Chart ◽

Paper Machine ◽

Statistical Control ◽

Operating Characteristics ◽

Small Shift

This paper is an attempt to assess if the manufacturing process of paper machine is in statistical control thereby improving the quality of paper being produced in a paper industry at the time of process itself. Quality is the foremost criteria for achieving the business target. Therefore, emphasis was made on controlling the quality of paper at the time of manufacturing process itself, rather than checking the finished lots at a later time. This control on quality will help the industry deduct the small shift in the process parameters and modify the operating characteristics at the time of production itself rather than receiving complaints from customers at a later stage. This paper describes controlling quality at the time of manufacture itself and helps the industry to concentrate on quality at low cost. The researcher has collected primary data at a leading paper industry during October, 2019. Though X-bar and Range charges were primarily used, CUSUM charts were used to sense the minor shifts in manufacturing process, to explore the possibility of adjusting process parameters during manufacture of paper.

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A Cost-Effective Decentralized Control for AC-Stacked Photovoltaic Inverters

Energies ◽

10.3390/en11092262 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2262 ◽

Cited By ~ 1

Author(s):

Hua Han ◽

Chao Luo ◽

Xiaochao Hou ◽

Mei Su ◽

Wenbin Yuan ◽

...

Keyword(s):

Decentralized Control ◽

Cost Effective ◽

Current Control ◽

Control Mode ◽

Communication Link ◽

Grid Voltage ◽

Point Tracking ◽

Pv Inverter ◽

Communication Links ◽

Voltage Phase

For an AC-stacked photovoltaic (PV) inverter system with N cascaded inverters, existing control methods require at least N communication links to acquire the grid synchronization signal. In this paper, a novel decentralized control is proposed. For N inverters, only one inverter nearest the point of common coupling (PCC) needs a communication link to acquire the grid voltage phase and all other N − 1 inverters use only local measured information to achieved fully decentralized local control. Specifically, one inverter with a communication link utilizes the grid voltage phase and adopts current control mode to achieve a required power factor (PF). All other inverters need only local information without communication links and adopt voltage control mode to achieve maximum power point tracking (MPPT) and self-synchronization with grid voltage. Compared with existing methods, the communication link and complexity is greatly reduced, thus improved reliability and reduced communication costs are achieved. The effectiveness of the proposed control is verified by simulation tests.

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Porosity Analysis of Additive Manufactured Parts Using CAQ Technology

Materials ◽

10.3390/ma14051142 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1142

Author(s):

Peter Pokorný ◽

Štefan Václav ◽

Jana Petru ◽

Michaela Kritikos

Keyword(s):

Manufacturing Process ◽

Scanning Speed ◽

Additive Technologies ◽

Integration Time ◽

Detector Resolution ◽

Porosity Analysis ◽

3D Scans ◽

Printing Direction ◽

Non Destructive

Components produced by additive technology are implemented in various spheres of industry, such as automotive or aerospace. This manufacturing process can lead to making highly optimized parts. There is not enough information about the quality of the parts produced by additive technologies, especially those made from metal powder. The research in this article deals with the porosity of components produced by additive technologies. The components used for the research were manufactured by the selective laser melting (SLM) method. The shape of these components is the same as the shape used for the tensile test. The investigated parts were printed with orientation in two directions, Z and XZ with respect to the machine platform. The printing strategy was “stripe”. The material used for printing of the parts was SS 316L-0407. The printing parameters were laser power of 200 W, scanning speed of 650 mm/s, and the thickness of the layer was 50 µm. A non-destructive method was used for the components’ porosity evaluation. The scanning was performed by CT machine METROTOM 1500. The radiation parameters used for getting 3D scans were voltage 180 kV, current 900 µA, detector resolution 1024 × 1024 px, voxel size 119.43 µm, number of projections 1050, and integration time 2000 ms. This entire measurement process responds to the computer aided quality (CAQ) technology. VG studio MAX 3.0 software was used to evaluate the obtained data. The porosity of the parts with Z and XZ orientation was also evaluated for parts’ thicknesses of 1, 2, and 3 mm, respectively. It has been proven by this experimental investigation that the printing direction of the part in the additive manufacturing process under question affects its porosity.

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Study on Reactive Power Compensation Control of STATCOM Based on MMC

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.530-531.1022 ◽

2014 ◽

Vol 530-531 ◽

pp. 1022-1025

Author(s):

Yan Xie ◽

Ya Ne Liao ◽

Hong Xie

Keyword(s):

Reactive Power ◽

Power Level ◽

Response Speed ◽

Reactive Power Compensation ◽

Current Control ◽

Control Mode ◽

Compensation Control ◽

Control Response ◽

In Series ◽

Level Converter

This paper introduced a new modular multi-level converter (MMC), which could enhance the voltage and power level by sub-converter modules in series and was easy to extend to any level of output. Its structure and working mechanism were described. By analyzing the performance of STATCOM based on MMC working conditions in the reactive power compensation, this paper studied compensation control theory in reactive changing conditions. To obtain compensation control response speed faster and better compensation effect, a compensation control strategy was proposed based on direct current control mode. The simulation results show the strategy has a better tracking precision and response speed for the reactive power compensation.

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H∞ Control to the BUCK-Type Switching Power Supply with Small Perturbation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.347-350.1358 ◽

2013 ◽

Vol 347-350 ◽

pp. 1358-1362

Author(s):

Zi Сheng Li ◽

Li Xu ◽

Bao Shan Yuan

Keyword(s):

Power Supply ◽

Current Control ◽

Control Mode ◽

State Variables ◽

Switching Power Supply ◽

Small Perturbations ◽

Switching Power ◽

Current Sampling ◽

Output Filter ◽

Filter Capacitor

The purpose in this paper is the design of the control to switching power supply for small perturbations. By the theoretical analysis and calculation, with the output filter inductor current and filter capacitor voltage switching power supply as two state variables, the conclusion is that control of the output filter inductor current sampling do well in the anti-jamming. The simulation is made for verification. And comparing the results, the current control mode shows a very strong anti-interference ability.

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Optimal Parameter Design of Solder Residue in Flip Chip Process by Using Taguchi Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.443.543 ◽

2010 ◽

Vol 443 ◽

pp. 543-548

Author(s):

Jian Long Kuo ◽

Kai Lun Chao ◽

Chun Cheng Kuo

Keyword(s):

Taguchi Method ◽

Product Quality ◽

Manufacturing Process ◽

Flip Chip ◽

Optimal Parameter ◽

Experimental Testing ◽

Signal To Noise Ratio ◽

Optimal Solution ◽

Passive Component

Because the solder residue was found in the manufacturing process which greatly affected the product quality, the purpose of this paper was to make the product quality improved and to find an optimal solution for process parameters in the flip chip process. The experimental testing was based on SMT manufacturing process. The amount and size of solder left on passive component in the process of manufacturing were considered as the quality traits. Since too many solders left on the passive component side during flux cleaning process, it was possible that the balling would be flowed into the chip, which caused the bump short in the chip and affected the quality of the product. In this paper, orthogonal array by using Taguchi method is adopted as the effective experimental method with the least experimental runs. Also, based on the quality evaluation of signal-to-noise ratio, the ANOVA is used to evaluate the effects of quality target according to the experimental results. The results reveal that the optimization in the process is confirmed. Therefore, this study can effectively improve the solder residue in semiconductor manufacturing process.

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Regulator Circuit Transformer Voltage-Second Product Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.529.501 ◽

2014 ◽

Vol 529 ◽

pp. 501-505

Author(s):

Chi Zhang ◽

Ming Zhi He

Keyword(s):

Power Supply ◽

Power Electronic ◽

Product Analysis ◽

Power Regulator ◽

Current Voltage ◽

Three Phase ◽

The Impact ◽

Power Electronic Technology ◽

Primary Current

With the continuous development of power electronic technology, the advantages of thyristor power regulator circuit gradually get more and more applications. It improves the quality of power supply, makes the equipment efficiency and power factor higher and so saves a lot of electricity. Through the calculation of the primary current when thyristor turns off in three-phase power regulator circuit with transformer load, the impact of the thyristors turn-off order on the transformer primary current voltage-second product is analysised, and through simulation the exactness is verified.

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Performance evaluation of voltage and current control mode controller for SEPIC converter in CubeSats application

2015 International Conference on the Industrial and Commercial Use of Energy (ICUE) ◽

10.1109/icue.2015.7280290 ◽

2015 ◽

Cited By ~ 1

Author(s):

K.D. Mananga Bayimissa ◽

A. K. Raji ◽

M. Adonis

Keyword(s):

Performance Evaluation ◽

Current Control ◽

Control Mode

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Quality of moxa wool contained in commercial moxibustion devices: test method and examples of waste particle concentration

Acupuncture in Medicine ◽

10.1177/0964528420946046 ◽

2020 ◽

pp. 096452842094604

Author(s):

O Sang Kwon ◽

Seong Jin Cho ◽

Kwang-Ho Choi ◽

Suk-Yun Kang ◽

Suyeon Seo ◽

...

Keyword(s):

Manufacturing Process ◽

Particle Concentration ◽

Scale Validation ◽

Chemical Stimulation ◽

Indirect Moxibustion ◽

Test Method ◽

Direct Moxibustion ◽

Wool Quality ◽

Waste Particles

Background: Moxibustion treatment involves a combination of thermal and chemical stimulation applied by the combustion of moxa wool. The quality of moxa wool is considered to be an important factor in moxibustion treatment traditionally and clinically. However, despite its importance, quantitative and objective methods for determining moxa wool quality are lacking. Methods: Moxa wool and commercial indirect moxibustion (CIM) device specimens were randomly collected, dried and strained through sieves of various sizes for 10 h. After sieving, the residues remaining on each sieve were collected. The collected samples were weighed and microscopically observed. Results: In this study, we observed that fibres mainly remained on sieves sized 425 μm, and particles were smaller than 300 μm. The residues between 425 and 300 μm varied between the products. In addition, moxa wool for direct moxibustion (DMW) exhibited significantly more fibres than moxa wool for indirect moxibustion (IMW). Most of the CIM devices using moxa wool had a quality similar to IMW, except for one CIM brand using moxa wool that contained three times more waste particles than IMW. Conclusion: Based on the results of this study, we conclude that the sieving method is useful for testing the quality of moxa wool even after the CIM manufacturing process. The sieve sizes of 425 and 300 μm could be used as a yardstick to determine the quality of moxa wool. Although this approach requires larger scale validation against existing standard methodologies, we believe it has great potential to be used to improve and safeguard the quality of moxa wool contained in commercial moxibustion devices.

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