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Although rework is labour intensive and conflicts with most modern manufacturing/assembly philosophies, realistic defect levels in surface mount technology (SMT) printed circuit board (PCB) assembly render rework indispensable on the shop floor. Most commercially available rework tools are manual or require very skilled operators for their efficient operation. The challenges of automating SMD rework are significant because the tools, their specifications and rework processes required are not fully understood, and the impact of rework processes on assembly quality and reliability are hotly debated. This paper describes an automated robotic rework cell for SMD and TH boards, and the method used for process characterisation of the solder paste dispensing system. The paper also describes equipment selection, the integration and interfacing of the dispensing equipment to the cell controller and the process characterisation experiments.

The purpose of this paper is to propose and demonstrate a new additive manufacturing approach that breaks the layer-based point scanning limitations to increase fabrication speed, obtain better surface finish, achieve material flexibility and reduce equipment costs.

The freeform additive manufacturing approach conceptually views a 3D article as an assembly of freeform elements distributed spatially following a flexible 3D assembly structure, which conforms to the surface of the article and physically builds the article by sequentially forming the freeform elements by a vari-directional vari-dimensional capable material deposition mechanism. Vari-directional building along tangential directions of part surface gives surface smoothness. Vari-dimensional deposition maximizes material output to increase build rate wherever allowed and minimizes deposition sizes for resolution whenever needed.

Process steps based on geometric and data processing considerations were described. Dispensing and forming of basic vari-directional and vari-dimensional freeform elements and basic operations of joining them were developed using thermoplastics. Forming of 3D articles at build rates of 2-5 times the fused deposition modeling (FDM) rate was demonstrated and improvement over ten times was shown to be feasible. FDM compatible operations using 0.7 mm wire depositions from a variable exit-dispensing unit were demonstrated. Preliminary tests of a surface finishing process showed a result of 0.8-1.9 um Ra. Initial results of dispensing wax, tin alloy and steel were also shown.

This is the first time that both vari-directional and vari-dimensional material depositions are combined in a new freeform building method, which has potential impact on the FDM and other additive manufacturing methods.

The purpose of this paper is to illustrate the use of Lean Six Sigma (LSS) and its associated tools to reduce dispensing errors in an inpatient pharmacy of a teaching hospital in Thailand.

The action research methodology was used to illustrate the implementation of Lean Six Sigma through the collaboration between the researcher and participants. The project team followed the Lean Six Sigma Define, Measure, Analyze, Improve, Control (DMAIC) methodology and applied its tools in various phases of the methodology.

The number of dispensing errors decreased from 6 to 2 incidents per 20,000 inpatient days per month between April 2018 and August 2019 representing a 66.66% reduction. The project has improved the dispensing process performance resulting in dispensing error reduction and improved patient safety. The communication channels between the hospital pharmacy and the pharmacy technicians have also been improved.

This study was conducted in an inpatient pharmacy of a teaching hospital in Thailand. Therefore, the findings from this study cannot be generalized beyond the specific setting. However, the findings are applicable in the case of similar contexts and/or situations.

This is the first study that employs a continuous improvement methodology for the purpose of improving the dispensing process and the quality of care in a hospital. This study contributes to an understanding of how the application of action research can save patients' lives, improve patient safety and increase work satisfaction in the pharmacy service.

The purpose of this paper is to examine drug dispensing and associated activity in Belo Horizonte, Brazil. The paper aims to describe factors associated with patient information giving and dispensing time.

A specific protocol for recording data gathered from observations included: number of dispensing sessions; medical specialties active at the time; medication number and type; dispensing outcome; if information giving was observed and dispensing time. Information giving and time were considered response variables. The chi‐square test and odds‐ratios were used to verify associations between response and explanatory variables.

In 43 percent (45) consultations, information giving accompanied dispensing and was associated with number of dispensing sessions and medical specialty offered on a particular day. Assistance time was associated with drug type and number, which increased as dispensing sessions decreased.

Seasonal variations in the demand for pharmacy assistance were not investigated and sample size precluded multivariate analyses. Consequently, new studies may deepen understanding about communication between physicians, pharmacy assistants and users.

Pharmacy staff could improve quality and efficiency if two aspects were taken into account: fluctuating workload, and external conditions within which tasks are undertaken.

The paper identifies external conditions that interfere with drug dispensing.

Liquid encapsulation techniques have been used extensively in advanced semiconductor packaging, including applications of underfilling, cavity‐filling, and glob top encapsulation. Because of the advanced encapsulation materials and the automatic liquid dispensing equipment involved, it is very important to understand the encapsulation material characteristics, equipment characteristics, encapsulation process development techniques in order to achieve the encapsulation quality and reliability. In this paper, the authors will examine the various considerations in liquid encapsulation applications and address the concerns on material characterization, automatic liquid dispensing equipment/process characterization and the encapsulation quality and reliability. The discussions will be helpful for future material and process development of semiconductor packages.

The purpose of this paper is to present a new tile dispensing decision-making to improve a row formation of a product flow-based tiling automation that has been being developed to support tile placement for custom mosaic design.

A new tile dispensing decision-making combines maximum tile loading and simple cycle strategies to minimize time for forming rows of tiles. The maximum tile loading strategy is for minimizing the number of loading rounds, while the simple cycle strategy is for minimizing the movement during the row formation.

This proposed decision-making has been developed; implemented in LabVIEW software; linked with other LabVIEW-based programs to control the system; and tested. The results showed the tile dispensing with the proposed decision-making performed better than the previous one.

The tiling automation is being developed and is currently on a prototyping stage.

Tile dispensing is critical for this row by row automated assembly, but the existing shortest distance strategy does not guarantee the best performance for a row formation. Therefore, the combination of the maximum tile loading and simple cycle strategies has been developed to improve the performance of the product flow-based tiling automation to better support assembly of custom mosaic design that requires individual tesserae to be assembled to particular positions to illustrate an image properly.

This paper aims to discuss the key factors affecting the quality characteristics, such as the number of solder balls, the spread distance of residual underfill and the completion time of the underfilling.

The Taguchi method is applied to configure the orthogonal table and schedule and execute the experiment. In addition, principal components analysis is used to obtain the points. Then, based on gray relational analysis and the technique for order preference by similarity to ideal solution, the closeness between each quality characteristic and the ideal solution is adopted as the basis for evaluating the quality characteristics.

The optimal parameter combination is proposed, which includes 4 dispensing (11 mg/dispensing), a “half flow” interval state, 80°C preheating module PCB board and an L-shaped dispensing path and verification testing is performed.

For vehicles and handheld electronic products, solder joints that connect electronic components to printed circuit boards may be cracked due to collision, vibration or falling. Consequently, solder balls are closely surrounded and protected by the underfill to improve joint strength and resist external force factors, such as collision and vibration. This paper addresses the defects caused during the second reflow process of a vehicle electronic communication module after the underfilling process.

This paper aims to study the relationship between the ball grid array (BGA) flip-chip underfilling process parameter and its void formation region.

A set of top-down scanning acoustic microscope images of BGA underfill is collected and void labelled. The labelled images are trained with a convolutional neural network model, and the performance is evaluated. The model is tested with new images, and the void area with its region is analysed with its dispensing parameter.

All findings were well-validated with reference to the past experimental results regarding dispensing parameters and their quantitative regional formation. As the BGA is non-uniform, 85% of the test samples have void(s) formed in the emptier region. Furthermore, the highest rating factor, valve dispensing pressure with a Gini index of 0.219 and U-type dispensing pattern set of parameters generally form a lower void percentage within the underfilling, although its consistency is difficult to maintain.

This study enabled manufacturers to forecast the void regional formation from its filling parameters and array pattern. The filling pressure, dispensing pattern and BGA relations could provide qualitative insights to understand the void formation region in a flip-chip, enabling the prompt to formulate countermeasures to optimise voiding in a specific area in the underfill.

The void regional formation in a flip-chip underfilling process can be explained quantitatively with indicative parameters such as valve pressure, dispensing pattern and BGA arrangement.

The increasingly improved automotive vehicle production technology has allowed consumers to purchase passenger cars and commercial vehicles at reasonably affordable prices. This has resulted in greater demands for the construction and installation of motor fuel dispensing facilities, or simply “gas stations”, in virtually all urban districts worldwide. However, unlike most consumer products, which are designed to be fire resistant, highly flammable gasoline dispensed at these facilities is intended and formulated to burn. Therefore, fire safety of motor fuel dispensing facilitates becomes a major concern since these facilities form one of the greatest fire hazards that millions of people visit everyday. This paper seeks to address this issue.

This paper reviews the current international and local legislation and requirements on fire safety in gas station facilities, and presents the findings of a case study conducted to evaluate fire prevention measures and fire protection equipment in five gas station facilities located in the growing City of Al‐Khobar, Saudi Arabia, where dispensing of motor fuel is carried out in an outside shaded area by station attendants.

The evaluation revealed that none of the five gas stations is complying with all fire safety regulations. Recommendations are made to improve fire safety at such facilities by regular inspection and evaluation.

Although the results are limited to Saudi Arabia the approach taken could be extended to other geographical areas.

The paper is of practical value to facility managers responsible for day‐to‐day operations of gas station facilities.

The paper reviews literature from North America as well as that pertaining to the legislation in the country where the case study facilities are located.

Organizational consultants employ scientific methodologies to collect data and generate an organizational diagnosis. Between‐method triangulation is a means of leveraging the strengths of several methods while mitigating weaknesses. This article briefly reviews common scientific data collection methodologies and provides an illustration of between‐method triangulation in organizational diagnosis. Interpretations of organizational social reality were based on the triangulation of data from interviews, systematic observation, observer‐as‐participant observation, and archival data. Between‐method triangulation resulted in a more complete assessment of organizational problems than any lone method.