Printed Wiring Boards Research Articles

Binarization of Printed Wiring Board Images with Scratches Using Convolutional Neural Network with U-Net Structure

This paper presents the method by which binarize Printed Wiring Board(PWB) images. Multilayer printed wired boards have many wiring layers inside the board, and the images capturing these wiring layers contains a large number of scratches and stains, because the wiring layer images are captured while the surface is thinly scraped. We aim to recover the wiring pattern as a binarized image from such images. We have devised an input layer based on the U-Net structure, which consists of 1) 3-channel RGB input (conventional U-Net), 2) 5-channel input by adding L and S channels of HLS color space to RGB, 3) 4-channel input by adding a binary image by Otsu's method of L to RGB, 4) a loop that repeats the structure of method 3), and compared them. As a result, we found that method 3) with Otsu's binarization added to the input was superior in all the indices of accuracy, F-measure, mIoU, and the number of breaks and short circuits.

Natural Fiber Incorporated Polymer Matrix Composites for Electronic Circuit Board Applications

There are many more applications for fibre-reinforced epoxy composites than there are for metals and alloys today. For example, sustainable, recyclable, and biodegradable reinforcements have been used in numerous studies to improve the mechanical and thermal properties of composite materials. It was discovered that the properties of epoxy-based composites could be improved by combining biosolid waste sugarcane bagasse ash fillers, madar fibre, and epoxy resin. Conventional compression molding techniques were used to prepare the sugarcane bagasse ash (SBA) particles and madar fibre-reinforced epoxy resin-based composites (PMCs), which were loaded with varying amounts of fibre and fillers. Hybrid biocomposites were evaluated for mechanical (tensile, flexural, impact, and hardness) and water absorption characteristics. Epoxy matrix composites containing 28 wt.% madar fibre and 7 wt.% sugarcane bagasse ash fillers had tensile, flexural, hardness, and impact values of 61 MPa, 147 MPa, and 54 kJ/m2, respectively.

Mathematical Modeling of Stress in Circuit Cards Represented by Mechanical Oscillatory Systems

Mathematical Modeling of Stress in Circuit Cards Represented by Mechanical Oscillatory Systems

Application to Industrial Use (4) Electronic, Electrical, and Information Applications, Part 1 Printed Wiring Board (PWB)

Application to Industrial Use (4) Electronic, Electrical, and Information Applications, Part 1 Printed Wiring Board (PWB)

Investigation of Teachers’ Reflections on Countrywide Tablet PC and Interactive White Board Initiative in Turkish Schools

The Turkish government made a significant decision in 2012 to transform its educational system and improve educational outcomes through technology. For this purpose, a consortium among different ministries initiated the “Movement of Enhancing Opportunities and Improving Technology” (FATİH) project with the aim of providing each K-12 student with a Tablet PC and every classroom with an Interactive Board using a high-speed Internet connection. Therefore, this study was designed to investigate teachers’ reflections on this countrywide technology integration initiative. In 2012 a pilot study in 52 public schools in 17 cities in Turkey was initiated. Participants consisted of 54 teachers in 11 of the pilot schools. Details from teachers’ reflections on technology use in teaching and learning as well as issues and problems they faced during the pilot study are provided. Participatory observations, structured interviews, and focus group meetings were held to collect data to answer the research questions. These data were analyzed using content analysis principles. Concerns-Based Adoption Model (CBAM), Technological Pedagogical Content Knowledge (TPACK), and Technology Acceptance Model (TAM) were used as the guiding framework to interpret this study’s results. Based on the principles of these three conceptual frameworks, results indicated several factors affected teachers’ effective use of technology. These factors can be categorized as teachers’ concerns, pedagogical issues, and attitudes toward technology use. Based on these results, in-service teacher training programs, including technological and pedagogical aspects on Tablet PC and interactive board use, are offered for teachers to improve their knowledge and embrace new technology. These results also provided important insights for policy-makers about the dynamics of countrywide technology integration projects

Electronic Circuit Board Design and Production Project Design and Teaching Innovation

Electronic Circuit Board Design and Production Project Design and Teaching Innovation

Novel lignin as natural‐biodegradable binder for various sectors—A review

AbstractLignin functions as an essential polymer in plants that forms the plant body's structural framework. The natural glue holds the cellulosic fibers together in the plant body, thereby providing rigidity and strength. Despite this, lignin shows promising relevance for biomaterial production due to its abundance, nontoxic nature and biodegradability. Considerably, adhesive components were derived from petroleum, which is increasingly more expensive. Hence, lignin, the natural glue in plant materials, gained much popularity because of its phenolic nature, making it an attractive substitute for adhesives. Lignin‐based binders are produced through phenols substitution in phenol‐formaldehyde resins with lignin due to their similar structural framework. Many researchers have confirmed the multifunctional applications of lignin, such as wood adhesive in fiber board, plywood and particleboard, a binder in printed wiring boards, abrasive tools, epoxy asphalts, epoxy wood composites, 3D printing, adhesive hydrogels, soil suppressants, lignocellulosic paper and coatings. This review presents a comprehensive description of the utilization of lignin‐based binders for different applications. The present work highlights the discussion on the various methods by which lignin can be used to replace synthetic binders. This review focuses on global research work introducing lignin in different chemical adhesives for a more cost‐effective and less harmful alternative.

High Dielectric Constant SiO2 Nanoparticles

SiO2 nanoparticles of average size 15-20 nm have been synthesized and its dielectric properties have been investigated as a function of frequency (between 20 Hz to 2 MHz). A very high dielectric constant of ca. 14000 at 20 Hz and at room temperature has been observed which is very high compared to the conventional bulk SiO2 particles (ca. 50-100). For this new SiO2 the loss value is found to be less than 1. These SiO2 nanoparticles with high dielectric constant and low loss can be offered its use in constructing high efficient electronic circuit boards and storage devices. Spectra between real and imaginary parts of dielectric constant reveal an inclined line with depressed semicircle. Impedance measurements have been performed to know the electrical properties of the novel SiO2 nanoparticles. XRD, TEM and FTIR characterizations confirm the solid state network structural, morphological shape and size, and chemical functionality of SiO2 respectively. Copyright © 2016 VBRI Press

Thermal design optimization of electronic circuit board layout with transient heating chips by using Bayesian optimization and thermal network model

This paper describes a method combining Bayesian optimization (BO) and a lumped-capacitance thermal network model that is effective for speeding up the thermal design optimization of an electronic circuit board layout with transient heating chips. As electronic devices have become smaller and more complex, the importance of thermal design optimization to ensure heat dissipation performance has increased. However, such a thermal design optimization is difficult because various trade-offs associated with packaging and transient temperature changes of heat-generating components must be considered. This study aims to improve the performance of thermal design optimization by artificial intelligence. BO using a Gaussian process was combined with the lumped-capacitance thermal network model, and its performance was verified. As a result, BO successfully found the ideal circuit board layout as well as particle swarm optimization (PSO) and genetic algorithm (GA) could. The CPU time for BO was 1/5 and 1/4 of that for PSO and GA. In addition, BO found a non-intuitive optimal solution in approximately 7 min from 10 million layout patterns. It was estimated that this was 1/1000 of the CPU time required for analyzing all layout patterns.

Design and Performance of Additively Manufactured In-Circuit Board Planar Capacitors

This article discusses the design and performance of planar capacitors built as pairs of conductive plates by additive manufacturing as part of an electronic circuit board. This article covers several geometries and layers of parallel plates that allow for different capacitance values, from a few picofarads (pF) to several nanofarads (nF). The dc, ac, and radio frequency (RF) characterization demonstrated superior performance compared to off-the-shelve surface mount device (SMD) capacitors up to 20 GHz. The additively manufactured capacitors exhibit breakdown voltages in excess of 1 kV and subpicoampere leakage currents, while the change in RF impedance changes, as a function of frequency, is a factor of $3\times $ smaller than SMD capacitors.

Passengers' travel behavior before and after the adjustment of regular bus collinear sections: A case study in the incipient phase of metro operation in Xiamen

Increasing Chinese cities are constructing the metro transit system, which is considered an effective way to reduce urban traffic congestion and meet the rapid growth of travel demand. However, the operation of a new metro line typically coincides with the adjustment or cancellation of regular bus routes along the metro corridor. This paper evaluates the impact of the introduction of a new metro system on the travel mode choice of passengers in the collinear segment. Through longitudinal analysis using the travel data of the same integrated circuit (IC) card owners collected before and after the opening of the metro line, we study how passengers’ travel behaviors changed under a dual traffic environment in which a new metro line has been opened and the collinear bus has been adjusted. In this study, we selected travel distance, travel time difference, whether traveling during peak hours, and the number of colinear stations as independent variables to build a binary logic regression to find out the probability of regular bus collinear segment passengers choosing the metro in the above circumstance. The logistic model shows that mode switching occurs at the highest rate when a regular bus line shares four collinear stations with the metro and declines when the collinear section becomes longer or shorter. Further, the research results indicate that passengers on the collinear sections are more inclined to choose buses during rush hour. This study provides new evidence to better help transit agencies coordinate existing bus services and the new metro system.

Preparation and Characterization of Narrow Size Distribution PMSQ Microspheres for High-Frequency Electronic Packaging

Polymethylsilsesquioxane (PMSQ) has become a kind of widely studied filler used in the electronic circuit board substrates due to its organic–inorganic hybrid structure, low dielectric constant, and good thermal stability, among other factors. Herein, the PMSQ microspheres were prepared by a two-step acid–base-catalyzed sol–gel method; the influences of reaction conditions including the ratio of water/methyltrimethoxysilane (MTMS), reaction temperature, concentration of the catalyst, and stirring time were systematically investigated; and the optimized reaction condition was then obtained towards a narrow particle size distribution and good sphericity. The microstructure of PMSQ microspheres was analyzed by the infrared spectrum and X-ray diffraction (XRD), which indicated that the as-prepared PMSQ had a ladder-dominant structure. The thermogravimetric analysis (TGA) demonstrated an excellent thermal stability of as-prepared PMSQ microspheres. More specifically, the dielectric constants at high frequency (1~20 GHz) of as-prepared PMSQ microspheres were measured to be about 3.7, which turned out a lower dielectric constant compared to SiO2 powder (≈4.0). This study paves the way to further improve the performance of the electronic circuit board substrates for the application of high-frequency electronic packaging.

Preparation of one-component addition-cure liquid silicone rubber coating with enhanced storage stability and bond strength

It is of great interest and challenge to simultaneously improve the storage stability and bond strength of one-component addition-cure liquid silicone rubber (OLSR) coating for electronic circuit board. In this work, we proposed an efficient approach to address this issue by incorporating both cyano-modification platinum catalyst (CN–PT) and urethane-containing poly(hydromethylsiloxane) (N-PHMS) into OLSR coating using a mechanical mixer. The CN–PT and N-PHMS were synthesized through thermal polymerization reaction and hydrosilylation reaction, respectively. The OLSR coating containing 0.3 phr CN–PT and 3 phr N-PHMS showed the best properties, with a tensile bond strength of 1.63 MPa, a storage period > 180 d at 25 °C, and a curing rate < 2 h at 80 °C. The salt-spray resistance and continuous power-on performance of OLSR coating were also improved, compared with pure OLSR coating. The synergism of CN–Pt and N-PHMS on the enhancement of both the storage stability and bond strength of OLSR coating was also explored. Our findings exhibited great potentials for fabricating OLSR coating with excellent long-term stable service performance including high storage stability and protective ability.

Evaluation of e-waste management systems in Malaysia using life cycle assessment and material flow analysis

The complexity of managing electrical and electronic waste (e-waste) prompted the need to evaluate the environmental performance of current e-waste management in Malaysia, focusing on future monitoring and planning. In this study, the environmental performance of four management options was evaluated based on the infrastructure currently available in Malaysia. Those options include 1) landfill disposal, 2) direct incineration with energy recovery, 3) materials recovery without energy recovery, and 4) materials recovery with energy recovery. These alternatives were evaluated using life cycle assessment (LCA) and material flow analysis (MFA). Two simple performance indicators, waste reduction rate (WRR) and environmental cost-benefit ratio (eCBR), were developed to interpret the study findings. Due to the lack of sufficient data on-site e-waste management and recycling in Malaysia, information from a variety of sources was utilized. Moreover, the focus of this study was limited to one specific type of e-waste – the printed wire board (PWB) from mobile phone. Surprisingly, our study concluded that direct incineration with energy recovery was the best of the four management options evaluated for e-waste management. The study results ran contrary to our initial expectations and the results of previous LCA studies on e-waste management. Because our interpretation of the study results had several limitations, recommendations were made to improve the evaluation of e-waste management and for more accurate and reliable analyses to assist in the future development of sustainable e-waste management practices. This study's findings could serve as a useful reference to the many stakeholders working to develop sustainable e-waste management in Malaysia.

Experimental Study on Graphene Coating Thermosetting Epoxy Polymer for the Manufacture of Electronic Circuit Boards

Graphene is a microstructure of graphite that has enormous properties and is also one of the carbon allotropes. There are several metals with low strength. The properties of these metals can be increased by coating the graphene. The primary goal of the work is to create composite graphene that exhibits the optimised properties and characteristics that meet the requirements of the industries. The properties of graphene when coated with other metals are studied and their applications in different industrial fields are analysed through several tests and experiments. Research-based on graphene coatings and composites is studied and the properties are adapted.

무기체계 연구개발단계에서의 체계적인 FMEA 실행 방법

Purpose: This paper proposes methods and procedures to effectively identify and select potential failure modes in the performance of faliure mode and effect analysis (FMEA). Specifically, a method is proposed to perform FMEA with emphasis on deriving failure mechanisms.<BR>Methods: The failure mechanism is known for a design change or improvement preventing recurrence and proactive. Therefore, it is important in designing FMEA to derive failure mechanisms and potential failure modes. This paper presents methods and procedures to derive failure mode and failure mechanism by analyzing past failure cases, usage/environmental condition parts (material), and interaction.<BR>Results: The effective design FMEA implementation procedure in the inorganic system development phase was described through the design FMEA practice case for antenna circuit card assembly and HL motor assembly among the drives used in induction weapon systems.<BR>Conclusion: The effectiveness of new identification of failure modes can be identified that the existing FMEA had not predicted by applying the proposed effective FMEA implementation methods and procedures to the weapon system development model.

Next Generation Industrial IoT Digitalization for Traceability in Metal Manufacturing Industry: A Case Study of Industry 4.0

This paper investigates digital traceability technologies taking careful consideration of the company’s needs to improve the traceability of products at the production of GPV Group as well as the efficiency and added value in their production cycles. GPV is primarily an electronics manufacturing service company (EMS) that manufactures electronic circuit boards, in addition to big metal products at their mechanics manufacturing sites. The company aims to embrace the next generation IoT technologies such as digital traceability in their internal supply chain at manufacturing sites in order to stay compatible with the Industry 4.0 requirements. In this paper, the capabilities of suitable digital traceability technologies are screened together with the actual GPV needs to determine if deployment of such technologies would benefit GPV shop floor operations and can solve the issues they face due to a lack of traceability. The traceability term refers to tracking the geolocation of products throughout the manufacturing steps and how that functionality can foster further optimization of the manufacturing processes. The paper focuses on comparing different IoT technologies and analyze their positive and negative attributes to identify a suitable technological solution for product traceability in the metal manufacturing industry. Finally, the paper proposes a suitable implementation road map for GPV, which can also be adopted from other metal manufacturing industries to deploy Industry 4.0 traceability at shop floor level.

Esim Mechanism

With 5G technology physical separation of SIM cards with mobile phone will be possible in coming days. Physical separation will help connecting remotely to various devices and easily for the mobile users to switch to new handsets with all data available on the other device too. The embedded Universal Circuit Card is form of programmable SIM card that can be embedded directly into a device with an objective to avoid to avoid sim card change in case where data, the application type or the operator is changed with less cost, less time and more efficiency. Major concern with use of ESIM is the mutual security between the user and the operator.

Low dielectric resins derived from hyperbranched carbosilane oligmers functionalized by benzocyclobutene groups

ABSTRACT Polycarbosilanes have been considered as potential materials used in electronic packaging and circuit boards owing to their excellent low-dielectric performance. In this work, we prepared new hyperbranched carbosilane oligomers (HCBOs) which were functionalized by benzocyclobutene (BCB) groups. HCBOs can be thermally cured to produce transparent (HCBRs) with low dielectric constant and high thermostability.

Bandpass Negative Group Delay Theory of Fully Capacitive Δ-Network

A particularly original negative group delay (NGD) theory of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $ </tex-math></inline-formula> -topology is developed in the present paper. The NGD three-port topology is a passive circuit purely constituted by capacitors network. The model of the proposed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $ </tex-math></inline-formula> -topology impedance 3-D matrix is analytically established in function of the capacitor elements. Then, the S-matrix model is derived by using the Y-to-S transform. By considering the S-matrix frequency responses, a bandpass (BP) NGD analysis of the capacitive <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $ </tex-math></inline-formula> -topology is originally elaborated. It is theoretically demonstrated that the passive <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $ </tex-math></inline-formula> -topology is susceptible to behave as a BP NGD circuit under an analytical condition between the constituting capacitor values. The design feasibility of the BP NGD function is experimentally verified with lumped capacitor components-based <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $ </tex-math></inline-formula> -circuit proof of concept. An electronic circuit board constituted by purely capacitive-network <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $ </tex-math></inline-formula> -circuit is fabricated as an original <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $ </tex-math></inline-formula> -circuit prototype. The tested board is constituted by arbitrary chosen capacitors, 100 nF, 10 nF and 0.1 nF. As expected, the calculation, simulation and measurement results, which are in very good agreement, confirm the BP NGD behavior. It is observed from measurement that it generates NGD of about −18.1 ns at a frequency of about 0.55 MHz and, lower and upper cut-off frequencies of about 0.33 MHz and 1.71 MHz. It is noteworthy that the transmission and reflection coefficients at very low frequency are independent of the capacitor values and analytically equal to 2/3 and 1/3, respectively.