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The purpose of this paper is to develop an optimization model allowing the choice of parts feeding policy to assembly lines in order to minimize total cost.

An integer linear programming mathematical model is developed to assign the optimal material feeding policy to each part type. The model allows choice between kitting, line stocking and just in time delivery policies.

The choice of assembly lines feeding policy is not trivial and requires a thorough economic comparison of alternatives. It is found that a proper mix of parts feeding policies may be better that adopting a single material delivery policy for all parts.

The model is aimed at single-model assembly lines operating in a deterministic environment, but can be extended to the multi-model line case. While relevant quantitative cost drivers are included, some context-related qualitative factors are not included yet. The model assumes that information about product structure and part requirements are known and that a preliminary design of the assembly system has been carried out.

Production managers are given a quantitative-decision tool to determine the optimal mix of material supply policies at an early decision stage.

Respect previous simplified literature models, this approach allows to quantify a number of additional factors which are critical for successful implementation of cost-effective parts feeding systems, allowing comparison of alternative policies on a consistent basis.

The paper's aim is to assess the impact of product related features on the performances of assembly line manufacturing systems, also providing a specific Design for Manufacturing and Assembly rating index to assess the goodness of a product design solution with respect to assembly line performances.

A computer simulation‐based parametric analysis was carried out to assess the impact of four major product‐related parameters. 216 different assembly line balance problem instances were evaluated. Findings allowed to develop a DFMA rating index specific for assembly line manufacturing as well as design guidelines.

Assembly sequence degrees of freedom and the ratio of the average task duration to the maximum duration are the most influencing parameters. While the former should be maximized, only a moderate task duration variability was found beneficial. The influence of other factors resulted less marked and changing on a case‐specific basis.

Complex interactions between product design features and line performances prevent generalization. The performed numerical experimentation, although extensive, remains somewhat limited respect all possible practical situations. The proposed rating index should be utilized while maintaining an overall perspective about the mutual influence of all parameters. Some suggested guidelines imply a trade off with traditional DFMA guidelines.

Product designers are given useful insights, tools and guidelines to develop better producible products. With the proposed ranking index a designer can easily rate his choices when selecting assembly tasks and sequences, as well as rank alternative product designs solutions.

The paper presents an original discussion about the impact of product design choices on assembly line performances. The developed DFMA rating index and guidelines are new.

The purpose of this paper is to develop analytical planning models to compare just-in-time (JIT) delivery and line storage (LS) alternatives for a continuous supply of materials to assembly lines.

A mathematical model is developed to size resources and to determine total system costs.

The choice of assembly lines feeding policy requires a thorough economic comparison of alternatives. However, the existing models are often simplistic, neglecting many critical factors which affect the systems’ performances. As a consequence, industries are unsure about which system is best for their environment. This model allows to compare the cost and suitability of two major continuous-supply alternatives in any specific industrial setting. Results of the model application are case-specific and cannot be generalized.

The model is aimed at single-model assembly lines operating in a deterministic environment. Although relevant quantitative cost drivers are included, some context-related qualitative factors are not yet included. The model assumes that the information about product structure and part requirements is known and that a preliminary design of the assembly system has been carried out.

Production managers are given a quantitative decision tool to properly assess the implementation of continuous material supply policies at an early decision stage, and determine which option is the best, also allowing to explore trade-offs between the alternatives.

With respect to previous simplified literature models, this new approach allows to quantify a number of additional factors which are critical for the successful implementation of cost-effective continuous-supply systems, including error costs. No other direct comparison of LS and JIT is available in the literature.

The aim of this paper is to develop a detailed descriptive model for kitting operations, allowing resources sizing and computation of systems’ economic performances.

A mathematical model allows to size resources, given product characteristics and production mix, and determines total system costs by assessing relevant cost items including investment costs (vehicles, containers, storage racks), direct operating costs (transport and kitting workforce, vehicles energy consumption and maintenance, quality costs), indirect operating costs (space requirements, work in process (WIP) and safety stock holding costs, administration and control).

The choice of parts delivery supply to assembly lines requires a thorough economic comparison of alternatives. However, existing models are often simplistic and neglect many critical factors which affect the systems’ performances. As a consequence, industries are unsure about which system is best for their environment. This model allows assessment of the cost and suitability of kitting in any specific industrial setting. Results of the model application are case-specific and cannot be generalized, but the major impact of labour and error correction cost has been highlighted.

The model at present focusses on the in-house kitting systems based on travelling kits concept only. Although all quantitative cost drivers are included, some context-related qualitative decision factors are not yet included. The model assumes that the information about product structure and part requirements is known and that a preliminary design of the assembly system (i.e. line balancing) has been carried out.

Production managers are given a quantitative decision tool to properly assess the implementation of kitting policies at an early decision stage. This allows exploring the trade-offs between the alternatives and properly planning the adoption of kitting systems, as well as comparing kitting with alternative material supply methods.

With respect to previous simplified literature models, this new approach allows quantification of a number of additional factors which are critical for successful implementation of cost-effective kitting systems, including kitting errors. An exhaustive cost estimation of kitting systems in multiple, mixed-model assembly lines is thus permitted.

Electrostatic precipitators (ESP) and fabric filters (FF) are the main air pollution control equipment utilized to clean dust laden fumes from utility boilers. The choice among these systems depends on specific site conditions such as dust characteristics, required efficiency, gas flowrate and temperature. ESP are generally characterized by higher capital investments and lower operating charges, while the opposite may be said for FF baghouses. As a consequence, ESP present higher total costs when high specific collection areas are required, as happens in the case of low‐sulfur high‐resistivity dust. However, significant reductions in both capital investment and operating charges may be obtained with pulsed energization of precipitators working in severe back corona conditions. This possibility greatly enlarges the field of applications in which ESP are a lower cost option compared to fabric filters. In the paper an economic comparison of pulse energized ESP, with conventional ESP, reverse‐air, shaker, and pulse‐jet baghouses is performed. A mapping of the operating conditions in which the adoption of each examined control technology is economically convenient is also defined.

Assembly systems require uninterrupted components' availability to feed workstations. This paper aims to propose a methodology to help managers in evaluating and selecting the most suitable policy for materials delivery to the shop floor. The analysis focuses on three basic policies, namely kitting, just in time kanban‐based continuous supply and line storage, even including class‐based hybrid policies.

Descriptive models are developed to design components' delivery systems and to compute their performances. Empirical criteria are utilized to associate specific policies to components classes in order to implement customized hybrid line feeding policies. A case study is then included to exemplify the method application and to show its capabilities as a decision making tool.

Hybrid feeding policies may be preferable to a single feeding policy common to all components. This is shown in a representative case study. However, in general there is a priori superior method and only a comparison of alternative feeding policies based on objective performance measures can determine the best approach in specific industrial applications.

The methodology is aimed at preliminary sizing and selection of alternative line feeding systems in deterministic environments. It is not intended for detailed performance analysis of assembly systems.

Production managers are given quantitative decision tools to properly select the components' delivery method at an early decision stage. This allows trade‐offs between alternatives to be explored in order to deploy customized feeding policies differentiated on components basis to better fit specific company requirements.

The paper extends previous descriptive models for line feeding systems and includes the possibility of hybrid policies.

The purpose of this paper is to estimate delivered hydrogen cost including both transport and expected accidents cost comparing compressed gas or liquid hydrogen road transport. The model allows to determine whether, in a given context, the risk of accidents is an influencing variable in the selection of the hydrogen transport mode. It also helps to select the lowest cost transport mode and route.

Transportation cost models are developed and integrated with a risk analysis model to determine expected accidents cost so that an overall delivered hydrogen cost can be computed. Alternative transport modes are compared on the basis of hydrogen demand, delivery distance and route type.

While safety cost in many cases can be considered negligible with respect to overall hydrogen transport cost, there are cases (high flow rate, long distance) where accident cost is relevant, especially in routes through densely populated areas. In such cases, factoring in accidents cost may significantly affect the break even point between CH2 and LH2 transport alternatives.

The paper only deals with proven road transportation methods (CH2 and LH2). Inclusion of alternative transport modes such as pipeline or hydrides is a future research goal.

Decision makers can examine the costs implied by hydrogen transportation alternatives in different economic scenarios factoring in safety costs to make informed decision.

Available hydrogen transportation cost models neglect any safety issue, while risk assessment models only consider accident consequences costs. This work integrates both views.

Logistic strategies represent a key factor to increase supply chain (SC) effectiveness, as the optimization of logistics networks enables transport and storage costs reduction as well as quick response leading to higher customer satisfaction. A useful approach for SC performance improvement may be pursued by resorting to advanced software tools able to analyze complex production scenarios, performing concurrent, synchronized and distributed simulations. Support to the logistics planning phase is offered by geographical information system technology, included in the simulation environment in order to manage related geographical data (i.e. warehouse location, choice of vehicle routeings, etc.). In the paper the main characteristics of the proposed hardware and software architecture have been illustrated, focusing attention on the logic phases for implementation by the transport federate. Furthermore, a preliminary functionality validation of the developed tool is presented with reference to simplified test cases.

This paper aims to discuss some relevant issues in the design and operation of material handling and storage systems (MH&SS) characterized by complex material flows and high‐traffic intensity. The paper seeks to provide solution examples and an analysis methodology to face large increases of materials flows through a redesign of the material handling and storage system.

At first, possible strategies to improve system performances when facing strong increments of material flows are presented and discussed. A significant case study is then analyzed in order to present a practical application of the proposed methodology. Resorting to discrete‐events simulation, the alternatives are verified, correct design choices are identified, and the resources are properly sized to develop a streamlined layout.

The paper recognises that design and upgrade of intensive material handling systems is a complex task asking for a careful study of alternatives and detailed system analysis, otherwise capacity problems and bottleneck phenomena may not be effectively solved.

This work focuses on a specific case study. The paper, therefore, will be of interest mainly to managers and designers of similar plants and large – intensive material handling systems.

The paper shows how the correct planning and analysis of design alternatives integrated with a detailed system simulation enable a drastic reduction of bottleneck phenomena, thus meeting the required capacity improvement goals when upgrading and redesigning complex and high‐volume material handling systems.

The paper, while providing insights to practitioners engaged in design and management of complex MH&SS, outlines a methodological approach which can be useful when facing major capacity improvement projects.

Describes the reengineering of a production line for household heating tubular radiators, assuming as a reference scenario the facility of one of the leading Italian manufacturers. After a preliminary characterization of products and manufacturing process, a thorough analysis of the production system has been carried out in order to highlight current problems and improvement strategies in the light of lean manufacturing concepts. Subsequently, suggests some corrective actions and also assesses their expected effectiveness in economic terms. In particular, improvement possibilities have been found in the areas of internal logistics through streamlining of materials flow and layout modifications, as well as process quality increase. Reengineering activities are especially aimed towards layout optimization mainly by resorting to a U‐shaped cell‐based architecture. Further, the reduction of rework percentage during the assembly phase has been pursued by properly modifying the operations sequence and through integration of a new automated testing station in the production line.