scholarly journals A compact LED-based projection microstereolithography for producing 3D microstructures

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ebrahim Behroodi ◽  
Hamid Latifi ◽  
Farhood Najafi
Keyword(s):  
Low Cost ◽  
Device Performance ◽  
3D Printer ◽  
Construction Process ◽  
Effective Parameters ◽  
Projection Microstereolithography ◽  
Commercial Applications ◽  
Accuracy Speed ◽  
Better Than

AbstractProjection microstereolithography (PµSL) is a promising additive manufacturing technique due to its low cost, accuracy, speed, and also the diversity of the materials that it can use. Recently it has shown great potentials in various applications such as microfluidics, tissue engineering, micro-optics, biomedical microdevices, and so on. However, studies on PµSL are still ongoing in terms of the quality and accuracy of the construction process, which particularly affect the fabrication of complex 3D microstructures and make it attractive enough to be considered for commercial applications. In this paper, a compact LED-based PµSL 3D printer for the fabrication of 3D microstructures was developed, and the effective parameters that influence the quality of construction were thoroughly investigated and optimized. Accordingly, a customized optical system, including illumination optics and projection optics, was designed using optical engineering principles. This custom 3D printer was proposed for the PµSL process, which besides improving the quality of construction, led to the reduction of the size of the device, its cost-effectiveness, and the repeatability of its performance. To demonstrate the performance of the fabricated device, a variety of complex 3D microstructures such as porous, hollow, helical, and self-support microstructures were constructed. In addition, the repeatability of the device was assessed by fabricating microstructure arrays. The device performance showed that the lateral accuracy of printing was better than 5 μm, and the smallest thickness of the printed layer was 1 μm. Moreover, the maximum printable size of the device was 6.4 mm × 4 mm × 40 mm.

scholarly journals Crack Restraining Methods and their Effects on the Microstructures and Properties of Laser Cladded WC/Fe Coatings

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2541 ◽  
Author(s):  
Qiu-Lian Dai ◽  
Can-bin Luo ◽  
Fang-yi You
Keyword(s):  
Wear Resistance ◽  
Laser Cladding ◽  
Low Cost ◽  
Annealing Treatment ◽  
Melting Process ◽  
Laser Cladding Process ◽  
Process Heat ◽  
Crack Susceptibility ◽  
Better Than

Laser cladded WC/Fe coatings have the advantages of low cost and high abrasion wear resistance. However, cracks always appear in WC/Fe coatings, which limits their industrial application. In this paper, the co-effects of the re-melting process, heat treatments, and amount of Co element on the cracking susceptibility, microstructures, and mechanical properties of WC/Fe laser cladding coatings were studied. Experimental results show that re-melting process is helpful to improve the surface quality of the coating and to reduce the cracking susceptibility. The hardness of the coating decreases slightly but distributes more uniformly. Cracks in the coating can be inhibited effectively by preheating the substrate to 250 °C and maintaining the temperature during the laser cladding process, as well as applying an annealing treatment at 300 °C for 1 h. Heat treatment also results in a slight decrease in the hardness. Crack initiation cannot be restrained completely by applying the above two methods when laser cladding a big area of coating. On the basis of the above two methods, addition of Co element to the coating can further improve its toughness and decrease the crack susceptibility. Crack-free WC/Fe coating can be manufactured when 8% Co is added, and its wear resistance is much better than that of the hardened medium steel, especially when the wear time is long.

scholarly journals Quality of Dried Anchovy (Stolephorus sp.) from Buru Island Produced by Using Closed Sun Dryer

2018 ◽  
Vol 21 (3) ◽  
pp. 543
Author(s):  
Imelda Krisanta Enda Savitri ◽  
Bernita Silaban ◽  
R.B.D. Sormin
Keyword(s):  
Traditional Method ◽  
Low Cost ◽  
National Standard ◽  
Plate Count ◽  
Drying Method ◽  
Vibrio Cholera ◽  
E Coli ◽  
Total Plate Count ◽  
Better Than

Anchovies drying method in Saliong, Batuboi village, Kayeli Bay has been done by spreading fish on the ground covered by mat or net due to low cost and easy to apply. However, there are no guarantee in the sanitation and hygienic. The objective of this research was to study the effect of closed sun drying method on the quality of dried anchovies (Stolephorus sp). The method was using closed cabinet sun dryer prototype covered by transparence plastic multi racks. Parameters observed involve: organoleptic, moisture content, acid insoluble, total plate count (TPC), E. coli, Salmonella sp., Vibrio cholera and fungi according to Indonesian national standard reference (SNI). The result showed the dried anchovy have an organoleptic grade refers to appearance, smells and texture were 8.40, 8.33 and 8.27 respectively. Moreover, moisture 17.50%; acid insoluble ash 0.32%; total bacterial (TPC) 6.92x102; E. coli, Salmonella sp., V. cholera and fungi were negative. For comparison, dried anchovy produced by using conventional/traditional drying had an organoleptic grade refers to appearance, smells and texture were 7.67, 7.73 dan 7.87 respectively; while moisture 16.93% ; acid insoluble ash 0.65%; total bacterial (TPC) 1.16 x103; E. coli, Salmonella sp., V. cholera and fungi were negative. According to the SNI 01-2891 BSN 1992, dried anchovy produced by using enclosed sun dryer better than dried anchovy produced by traditional method.

scholarly journals Message Broadcasting via a New Fault Tolerant Irregular Advance Omega Network in Faulty and Nonfaulty Network Environments

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
Ved Prakash Bhardwaj ◽  
Nitin
Keyword(s):  
Fault Tolerant ◽  
Interconnection Network ◽  
High Reliability ◽  
Low Cost ◽  
Routing Algorithm ◽  
Multiple Faults ◽  
Message Broadcasting ◽  
Double Switch ◽  
Better Than

Interconnection Network (IN) is a key element for all parallel processing applications. Multistage Interconnection Network (MIN) is an efficient IN for these applications, as it has the quality of excellent performance at low cost with high reliability. MINs are effective medium for message broadcasting. Doing the same task in faulty situations is a critical challenge. In this paper, we have presented a new Fault Tolerant Interconnection Network named as Irregular Advance Omega Network (IAON); also we have presented its routing algorithm. IAON is the modified form of Advance Omega Network. The proposed MIN can endure multiple faults and provides a suitable path between every source to every destination. We have examined the fault tolerance capacity of IAON and compared its performance with other existing MINs. In order to check the performance of proposed MIN, message broadcasting was performed in three conditions as follows: (1) when network was fault free; (2) when network was Single Switch Faulty in every stage; (3) when network was Double Switch Faulty in every stage. Results showed that IAON performed better than the earlier proposed MINs.

Investigation of Delta Robot 3D Printer for a Good Quality of Printing

2017 ◽  
Vol 870 ◽  
pp. 164-169 ◽  
Author(s):  
Cheng Tiao Hsieh
Keyword(s):  
3D Printing ◽  
Low Cost ◽  
Standard Procedure ◽  
Smart Manufacturing ◽  
The Internet ◽  
3D Printer ◽  
Printing Industry ◽  
Manufacturing Environment ◽  
3D Printers

Within this couple of years, a group of skilled people called “Maker” are interested in building everything by themselves. They attempt to develop a small manufacturing environment where allows people to execute a low cost fabrication task. In order to achieve this goal, they utilized flexible and smart manufacturing machines like 3D printers, laser cutter and small CNC. Especially 3D printer, its excellent performances had grasped many government administrators’ attention and developing 3D printing industry has become an important policy of many countries. Some of 3D printing patents have been expired within recent years. This event makes opens sources of 3D printers grow very fast. The Kossel Mini, Rostock and Prusa i3 are the typical examples. All of development kits of the above printers can be freely obtained from the Internet. This event makes a low cost fabrication become possible. However, the quality of their printed parts is dependent on a series of calibrations. The calibrations include defining the dimensions of hard frame of the printer, configuring firmware and setting building parameters of software. In order to let users to go through entire calibrating process, this paper proposed a standard procedure to calibrate Kossel Mini as well as make it print a good quality part.

Development of a low-cost dynamic filter immersed in activated sludge system

2006 ◽  
Vol 6 (6) ◽  
pp. 111-117 ◽  
Author(s):  
G.H. Chen ◽  
S.K. Pang
Keyword(s):  
Low Cost ◽  
Wastewater Reuse ◽  
Cost Effective ◽  
Permeate Flux ◽  
Effluent Quality ◽  
Cost Effective Treatment ◽  
Low Strength ◽  
Dynamic Filter ◽  
Better Than

Wasted non-woven material was employed to develop a dynamic filter immersed in bioreactor (DFIB) to treat low strength wastewater. A bench-scale DFIB was investigated to evaluate its feasibility. The maximum permeate flux of this innovative DFIB was more than 3 times greater than that of a conventional non-woven filter and even similar to that of a mesh filter, while the effluent quality of the developed DFIB in terms of turbidity, SS, and COD was better than that of a mesh filter, which were below 1.5 NTU, 3 and 35 mg/L, respectively. Such effluent quality with appropriate disinfection could meet the requirement for wastewater reuse for various urban usages. The acceptable MLSS level was identified not greater than 5 g/L in order to secure the effluent quality, when the maximum permeate flux of 1.5 m3/m2·day and daily backwash are applied. The large permeate flux rate and relatively high MLSS level of the DFIB can achieve cost-effective treatment of low strength wastewater.

Effect of Computerized Auditory Training on Speech Perception of Adults With Hearing Impairment

2013 ◽  
Vol 20 (3) ◽  
pp. 91-106 ◽  
Author(s):  
Rachel Pizarek ◽  
Valeriy Shafiro ◽  
Patricia McCarthy
Keyword(s):  
Hearing Loss ◽  
Speech Perception ◽  
Literature Review ◽  
Low Cost ◽  
Experimental Designs ◽  
Auditory Training ◽  
Hearing Impairments ◽  
Communicative Disorders ◽  
And Training

Computerized auditory training (CAT) is a convenient, low-cost approach to improving communication of individuals with hearing loss or other communicative disorders. A number of CAT programs are being marketed to patients and audiologists. The present literature review is an examination of evidence for the effectiveness of CAT in improving speech perception in adults with hearing impairments. Six current CAT programs, used in 9 published studies, were reviewed. In all 9 studies, some benefit of CAT for speech perception was demonstrated. Although these results are encouraging, the overall quality of available evidence remains low, and many programs currently on the market have not yet been evaluated. Thus, caution is needed when selecting CAT programs for specific patients. It is hoped that future researchers will (a) examine a greater number of CAT programs using more rigorous experimental designs, (b) determine which program features and training regimens are most effective, and (c) indicate which patients may benefit from CAT the most.

Kepuasan Masyarakat Terhadap Pelayanan Kelurahan Setelah Pemekaran Di Tangerang Selatan

Liquidity ◽  
2018 ◽  
Vol 2 (2) ◽  
pp. 151-159
Author(s):  
Pitri Yandri
Keyword(s):  
Public Perception ◽  
Service Personnel ◽  
Urban Services ◽  
Hospitality Workers ◽  
Care Workers ◽  
Before And After ◽  
Cartesian Diagram ◽  
Better Than

The purpose of this study is (1) to analyze public perception on urban services before and after the expansion of the region, (2) analyze the level of people's satisfaction with urban services, and (3) analyze the determinants of the variables that determine what level of people's satisfaction urban services. This study concluded that first, after the expansion, the quality of urban services in South Tangerang City is better than before. Secondly, however, public satisfaction with the services only reached 48.53% (poor scale). Third, by using a Cartesian Diagram, the second priority that must be addressed are: (1) clarity of service personnel, (2) the discipline of service personnel, (3) responsibility for care workers; (4) the speed of service, (5) the ability of officers services, (6) obtain justice services, and (7) the courtesy and hospitality workers.

Development and Application of Quality Control System for Highway Subgrade Construction

2019 ◽  
Vol 2 (5) ◽  
Author(s):  
Tong Wang
Keyword(s):  
Quality Control ◽  
Real Time ◽  
Detection Method ◽  
System Development ◽  
Effective Control ◽  
Construction Process ◽  
Development Mode ◽  
The Road ◽  
Whole Process

The compaction quality of the subgrade is directly related to the service life of the road. Effective control of the subgrade construction process is the key to ensuring the compaction quality of the subgrade. Therefore, real-time, comprehensive, rapid and accurate prediction of construction compaction quality through informatization detection method is an important guarantee for speeding up construction progress and ensuring subgrade compaction quality. Based on the function of the system, this paper puts forward the principle of system development and the development mode used in system development, and displays the development system in real-time to achieve the whole process control of subgrade construction quality.

Implementasi Voip Server Berbasis IPV6 Dengan Raspberry PI

2019 ◽  
Vol 9 (01) ◽  
pp. 47-54
Author(s):  
Rabbai San Arif ◽  
Yuli Fitrisia ◽  
Agus Urip Ari Wibowo
Keyword(s):  
Internet Protocol ◽  
Wireless Transmission ◽  
Raspberry Pi ◽  
Test Results ◽  
Average Delay ◽  
Ipv6 Network ◽  
Ip Network ◽  
Selection Of ◽  
Better Than

Voice over Internet Protocol (VoIP) is a telecommunications technology that is able to pass the communication service in Internet Protocol networks so as to allow communicating between users in an IP network. However VoIP technology still has weakness in the Quality of Service (QoS). VOPI weaknesses is affected by the selection of the physical servers used. In this research, VoIP is configured on Linux operating system with Asterisk as VoIP application server and integrated on a Raspberry Pi by using wired and wireless network as the transmission medium. Because of depletion of IPv4 capacity that can be used on the network, it needs to be applied to VoIP system using the IPv6 network protocol with supports devices. The test results by using a wired transmission medium that has obtained are the average delay is 117.851 ms, jitter is 5.796 ms, packet loss is 0.38%, throughput is 962.861 kbps, 8.33% of CPU usage and 59.33% of memory usage. The analysis shows that the wired transmission media is better than the wireless transmission media and wireless-wired.

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