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A critical analysis of packaging and sealing methods for integrated circuits, hybrid microcircuits and multichip modules has been done. The best hermetic and high yield weld seal is examined along with other conventional seals like solder seal, frit seal and plastic seal with special emphasis on materials and processes involved in each case. An overview of emerging technology is also presented. A comparative analysis is made for selection of the right technology and material for a particular requirement.

To determine the feasibility of sealing and finishing conformal cooling/heating channels in profiled edge laminae (PEL) rapid tooling (RT) using abrasive flow machining (AFM).

Sample PEL tools constructed of both aluminum and steel were designed and assembled for finishing by AFM. A simple design of experiments approach was utilized. Output parameters of interest included the material removal, surface roughness improvement and, most importantly, the ability to withstand a pressurized oil leak test.

AFM significantly improved the finish in the channels for aluminum and steel PEL tooling. Leak testing found that AFM also improved the sealing of both stacks at static pressures up to 690 kPa. The steel tooling appeared to benefit more from the AFM process. It has been postulated that the primary cause of the sealing is the plastic deformation of workpiece material in the plowing mode.

The conformal channels studied had a simple cross‐sectional geometry and straight runs. The PEL tools were only made of two materials. However, the research results show great promise for large RT, including thermoforming and composite forming molds where temperature control is a critical issue.

The ability to seal the interfaces between individual laminae expands the potential application of AFM tremendously. AFM also has the potential to finish a wide range of internal passages in a variety of RT.

AFM has been previously used for finishing stereolithography prototypes. This is the first known attempt to seal and finish channels in laminated RT using AFM.

States that magnetic fluids, in a zero leakage, non‐wearing seal, offer an innovative solution to the problems of harmful emissions from rotating process equipment. Discusses the properties and uses of the new GT series of ferrofluids from AP&T Ltd.

Worldwide, companies are interested in improving processes and reaching high levels of quality through the adoption of various systems. For example, they implement quality management methodologies, such as Lean, with the aim of reducing waste and cost. In the food sector, however, companies also adopt food safety management systems, such as BRC (British Retail Consortium), destined to comply with the standards of hygiene, food safety and quality systems. Interestingly, both Lean and BRC seek to boost quality. Thus, both should be able to work as a single system and cooperate to add value to a company without duplicating efforts. By solving the problems in the bag sealing process of an Ecuadorian company through the implementation of Lean tools incorporated in the steps of the DMAIC methodology (define-measure-analyze-improve-control), and then framing a cooperation matrix of Lean tools and BRC clauses, this paper seeks to demonstrate their feasible cooperation.

One of the most well-known methodologies for process improvement is the DMAIC methodology. Through the sequence of the DMAIC steps, the main problem of an Ecuadorian company that produces flexible packaging for food was identified. With the voice of the customer (VOC) from historical customer surveys of the company, the common issues were found. Similarly, historical data of non-conformities required by ISO-9001: 2015 provided insightful information for this phase. In order to measure the current quantitative state of the processes, a VSM (value stream map) was jointly employed with an operator balance chart. Data was collected during the whole operational month. Having this quantitative data, and with the ideas generated from the Kaizen events, improvement initiatives were analyzed and proposed. The proposed solutions involve production and maintenance teams. After some tests, it was verified that all these improvements had had a positive impact on the company. Finally, it was analyzed that Lean tools can collaborate and also be used as proof for BRC requirements. Thus, a correlation matrix between them was built, which demonstrates cooperation between both systems.

The results of this study indicate that Lean can cooperate in the pursuit of the BRC Standard for food packaging companies. This is shown through the case study of the Ecuadorian company, which implemented Lean tools and reduced its costs by shortening lost time and reducing set up time in the machines employed to cut and seal bags. Additionally, overall equipment effectiveness (OEE) from machines 1 and 2 rose their values considerably. Since BRC is a certifiable standard, it contains clauses that must be achieved in order to get the certification. By using Lean tools, it was possible to comply with some of the clauses of the BRC standard. A matrix was built so that it could be identified that Lean tools can work together with BRC, and thus, reduce costs and waste, while simultaneously complying with the safety and quality standards that the standard guarantees.

This research had two limitations. The first limitation is related to time. The data was collected in a month due to the project's deadline. For further research, it is recommended to increase this period of time to at least three months of production. The second limitation is related to the processes studied, which are associated with the time period. This study encompasses two major processes, which present major problems. For further investigations, longer periods of time can allow to include more processes from the company.

The implications of this project rely on the fact that the company achieved a better level of efficiency. The application of Lean tools reduces waste in the company. Basically, the waste was associated with lost time in machines 1 and 2 from the cutting and sealing processes, which was mainly produced by mechanical malfunction and inefficient maintenance. These problems had a direct relationship with the bad quality of the bags since the machines operate almost fully automatically. Additionally, mechanical problems caused by inefficient maintenance have a direct impact on quality aspects of the bag, like correct dimensions or a proper seal. Moreover, these problems generate a loss of time since the operator must stop the machine during production time in order to fix it. Machines 1 and 2 reduced their lost time drastically. Furthermore, by using Lean tools alongside the BRC methodology, the company can now reduce the resources that are destined for Lean projects and the BRC certification. Specifically, as a result, Lean tools and their documents can serve as proof of compliance with certain BRC clauses.

These improvements impact the company's profits, and therefore the workers. Since there is a significant reduction in the company's costs, and also an increment in the company's production, the company will probably require hiring new employees. In this way, more job opportunities will be generated.

The originality of this work relies on the nature of the research and the type of production facility. Previous studies have examined Lean tool applications in many settings. There are a few studies regarding the adoption of BRC standards. However, and definitely, the merge between Lean tools and a food safety management system is novel, since there are few to almost no articles that have been published using such a merge. The positive outcomes that were obtained not only prove that both methodologies are compatible, but they can also encourage further research on the applicability and functionality of merging two methodologies similar to the ones used during this research. Regarding the production facility, very few articles have been published about flexible packaging companies, and this article will help further research in this field.

Summarizes briefly the dramatic advances made in the reliability of mechanical seals for rotating shafts in the process chemical and petrochemical industries over the last 30 years. Shows that expected mean time before failure has improved from tens of days to years over that time.

Reviews the current use of paint robots in the automotive industry and looks at the further development of robot control which has extended its reach into the area of process control. Summarizes the potential of the developing technologies.

The purpose of this paper is to investigate the dynamic characteristics of spiral groove liquid film seal under the effect of thermal–fluid–solid coupling.

The dynamic analysis model of spiral groove liquid film seal under the effect of thermal–fluid–solid coupling was established by perturbation method. The steady-state and perturbation Reynolds equations were solved, and the steady-state sealing performance and dynamic characteristic coefficients of the liquid film were obtained.

Compared with the liquid film without coupling method, a divergent seal gap is formed between the seal rings under the effect of thermal–fluid–solid coupling, the minimum liquid film thickness decreases, the dynamic stiffness and damping coefficients of the liquid film are increased and the thermoelastic deformation of the end-face improves the dynamic performance of the liquid film seal.

The dynamic characteristics of the spiral groove liquid film seal under the effect of thermal–fluid–solid coupling are studied, which provides a theoretical reference for optimizing the dynamic performance of the non-contacting liquid film seal.

Among others, the resuspension of fine and ultrafine particulate matters (PMs) on air due by land take effect is an uncovered issue. The relation between land use change and fluxes of PM is not systematically observed even if the common classification of ecosystem services (ESs) clearly shows relationship between soil and aerosol concentrations. Soil does not act only as carbon pool, but it is also a crucial variable for the resuspension dynamic of particulates. If key policies of sustainable urban development is focused on “quality of life,” it is necessary to map and evaluate the effect of land take on airborne fluxes in metropolitan areas. The paper aims to discuss these issues.

The paper allows to introduce pioneer studies on air quality in large urban areas outling a methodology of particulate field measurement. It introduces newer quantitative/qualitative assessment of environmental effect due to urbanization ensuring a major efficiency on ES degradation.

Expected results are the estimation of resuspension dynamics of aerosol for typical land cover pattern.

Implications are mainly destinated to increase significant knowledge and general awareness of the environmental effect caused by urban growth: urban areas act as a hotspot for health risk as both particle sources and human population are concentrated in these areas.

Considering that cardiovascular diseases are significantly caused by air quality, the paper aims to support sustainable planning policies aimed to achieve a better quality of environment on urban areas.

The purpose of this paper is to present the development of a maintenance engineering policy in the context of a decision support model based on a production machine process perspective.

The structure of the policy is called the maintenance decision support (MDS) model, which consists of three steps: initial setup, deterioration monitoring, and decision making. A detailed presentation of each step of the proposed model together with a real case example from the pulp manufacturing industry proves the applicability of the model.

Validation of the proposed MDS model is as follows. In Task 1 of Step 1, the cutting, sealing, and perforating line processes are classified as critical machining processes. The analysis of Task 2 of Step 1 found that cutting knife, bearing, and motor are classified as the components that most possibly contribute to the cutting appearance quality. In Task 3 of Step 1, it was found that the cutting knife is classified as a maintenance-significant component with non-repairable and single-component type characteristics. The result of Step 2 suggested that at the 29th hour of operating time, the decision of do-something was suggested. In the following step (Step 3), for the case of the cutting knife, which has been classified as a non-repairable type component, the decision to perform preventive replacement of cutting knife is recommended to be carried out at the 29th hour of operating time.

The uniqueness of this model is that it systematically considers different machinery component(s) characteristics, including single- and multiple-component cases, repairable and non-repairable types, and functional or/and physical failure types, to make maintenance decisions.

The proposed MDS model provides a systematic guideline for identifying, evaluating, and monitoring, which makes maintenance-related decisions. Three significant maintenance decisions can be determined based on the proposed MDS model, which includes an appropriate time-to-perform maintenance, correct maintenance actions to be performed, and the right component required for maintenance (for multi-component cases).

One of the vital elements in considering the production machine process perspective toward the development of the MDS model is the need to use product output/quality characteristics for machine deterioration-monitoring and decision-making processes.

For a considerable time moisture level has been a problem for hermetic package assembly, although the materials used were only metallics. Today semiconductor technology is cost driven, therefore organic materials must be taken into account. Obviously there are many different issues involved. This paper focuses on mechanisms involving hermetic packages with silver glass die attach material. Silver glass, as a die attach paste, is mixed with organic solvents, so different chemical reactions are studied. It is then shown how to achieve a low moisture level. the authors' company has performed a design of experiments (DoX) in order to identify the key parameters and their interactions. A mathematical prediction model has been determined, and the result of this theoretical study is confirmed with experimental results.