Entire Production Line Research Articles

A formal framework for software product lines

ContextA Software Product Line is a set of software systems that are built from a common set of features. These systems are developed in a prescribed way and they can be adapted to fit the needs of customers. Feature models specify the properties of the systems that are meaningful to customers. A semantics that models the feature level has the potential to support the automatic analysis of entire software product lines. ObjectiveThe objective of this paper is to define a formal framework for Software Product Lines. This framework needs to be general enough to provide a formal semantics for existing frameworks like FODA (Feature Oriented Domain Analysis), but also to be easily adaptable to new problems. MethodWe define an algebraic language, called SPLA, to describe Software Product Lines. We provide the semantics for the algebra in three different ways. The approach followed to give the semantics is inspired by the semantics of process algebras. First we define an operational semantics, next a denotational semantics, and finally an axiomatic semantics. We also have defined a representation of the algebra into propositional logic. ResultsWe prove that the three semantics are equivalent. We also show how FODA diagrams can be automatically translated into SPLA. Furthermore, we have developed our tool, called AT, that implements the formal framework presented in this paper. This tool uses a SAT-solver to check the satisfiability of an SPL. ConclusionThis paper defines a general formal framework for software product lines. We have defined three different semantics that are equivalent; this means that depending on the context we can choose the most convenient approach: operational, denotational or axiomatic. The framework is flexible enough because it is closely related to process algebras. Process algebras are a well-known paradigm for which many extensions have been defined.

Precise Detection Technology

This paper mainly studies the application in the assembly line production by precision instruments and sensors, proposed the use of sensor technology and WEB technology to control lines on the transmission system. It can enhance the production of the compatibility between devices by real-time monitoring, so that each process can be more perfect articulation and reach to reduce the production cost for the entire production line monitoring.

Various strategies to handle cannibalization in a competitive duopolistic market

AbstractWe investigate an incumbent's optimal sequential introduction of new products over two periods in a competitive duopoly setting. The firm would like to preempt and counter competition from a future entrant. Alternatively, the firm should consider that one of its products might decrease sales for another of their products, a threat commonly known as cannibalization. In this paper, we examine three sequential introduction strategies. We find that a firm's optimal introduction sequence is governed by pressures from competition and cannibalization in the market. In general, competition has greater impact on firms’ profits than cannibalization. Introducing a high‐end product before a low‐end product can alleviate cannibalization for a weak entrant. In particular, the profit loss caused by competition is greater than that caused by cannibalization. When competition is intense, firms should consider alleviating the profit loss from competition over cannibalization by introducing a low‐end product before a high‐end product. In that case, the incumbent's high‐end product's quality must be no lower than the entrant's quality but the profit is derived mostly from the mark‐up on the low‐end product. Much of the high‐end product's profit is sacrificed in order to maximize profit from the entire product line. When cannibalization is intense and competition is mild (due to a weak entrant), the incumbent's profit gap between the high‐end and low‐end products is high. In that case, the firm can no longer afford to sacrifice its high‐end products’ profit and the order of introduction reverses.

Type checking annotation-based product lines

Software product line engineering is an efficient means of generating a family of program variants for a domain from a single code base. However, because of the potentially high number of possible program variants, it is difficult to test them all and ensure properties like type safety for the entire product line. We present a product-line-aware type system that can type check an entire software product line without generating each variant in isolation. Specifically, we extend the Featherweight Java calculus with feature annotations for product-line development and prove formally that all program variants generated from a well typed product line are well typed. Furthermore, we present a solution to the problem of typing mutually exclusive features. We discuss how results from our formalization helped implement our own product-line tool CIDE for full Java and report of our experience with detecting type errors in four existing software product line implementations.

Turn-and-Earn in a Product Line: The Impact of Product Substitutability

When manufacturers do not have sufficient capacity to meet demand and they cannot increase prices, they have to determine other methods to allocate goods among retailers. A common allocation mechanism is based on a retailer's sales history: a retailer that has ordered larger quantities in the past should get a greater allocation than a retailer that has historically ordered smaller quantities. This mechanism, known as a turn-and-earn allocation rule, is commonly used in many industries such as automobiles, microprocessors, video game consoles, etc. The existing literature has considered the effect of turn-and-earn allocation rules when a manufacturer sells a single product. However, when we consider a product line, it is not clear whether the manufacturer is better off basing its allocation on the sales history of the entire product line or basing allocation solely on the sales history of the product in short supply. In particular, a shortage of one product can lead retailers and consumers to move toward other products in the line. This, in turn, can have an effect on the manufacturer's optimal allocation mechanism. We examine this issue by developing a model of a supplier selling two substitutable goods through two retailers. Within this setup, we introduce a general turn-and-earn allocation rule that allows the entire sales history to influence allocation levels. Counter to previous work, we show that certain turn-and-earn rules not only help the manufacturer, but they can also help the retailer and increase total supply chain profits.

Hierarchical performance measurement and modeling of the linux file system (abstracts only)

File systems are very important components in a computer system. File system simulation can help to predict the performance of new system designs. It offers the advantages of the flexibility of modeling and the cost and time savings when utilizing simulation instead of full implementation. Being able to predict end-to-end file system performance against a pre-defined workload can help system designers to make decisions that could affect their entire product line, affecting several million dollars of investment. This paper presents a detailed simulation-based performance model of the Linux ext3 file system. The model is developed using Colored Petri Nets. A performance study using the model shows that the obtained results are close to the expected behavior of the real file system. The model shows that file system parameters have significant impact on the performance of the I/O when compared to the parameters of the disk subsystem.

Whose customers are they?

PurposeMany product organizations recognize the benefits of outsourcing manufacturing of key components or even entire product lines to China and other low labor cost countries. But while the cost savings are obvious, many product companies fail to grasp the parallel risk of their own distributors or retailers by‐passing them to source products directly from offshore suppliers. The author discusses case examples of companies that do a good job of anticipating and addressing this threat through a range of approaches to building strong connections to end customers. The author proposes six key strategies for companies in this situation.Design/methodology/approachIn this article, Jackson cites a number of case examples of businesses that have built strong connections to end customers even though they typically reach these through distributors or retailers. Examples industries included in the article are durable consumer goods and medical products. The author then draws lessons that can be applied broadly by any company concerned about the risks of distributors or retailers sourcing private label product directly from off‐shore suppliers.FindingsThe author proposes six priorities for defending against disintermediation by distributors and offshore suppliers: acknowledge the urgency of the threat; reinforce brands; find new ways to link to customers; look for mass‐customization opportunities; enter into creative partnerships; be serious about services.Originality/valueThis article sheds light on the risk of disintermediation for product companies using offshore suppliers, and strategies that can be used to mitigate this.

Quantitative analysis for peach production line management

The quantitative analysis, including reliability and maintainability which are of the fundamental issues for the operation management of an automated peach production line, was developed. Descriptive statistics of all the failures at machine and line level were shown, and the most critical machines under failures according to several criteria were determined. The best fit of the failure data between the common theoretical distributions was found and the respective parameters were identified. Moreover, the reliability and hazard rate models for the entire production line were calculated. They both proved to be useful tools to assess the current situation, and to predict reliability, mainly in short term, for upgrading the operation management of the peach production line. It was pointed out that (a) the mean time-to-failure (TTF) is approximately 650 min whereas the mean time-to-repair (TTR) a failure amounts to approximately 70 min. (b) The failure times follow the logistic distribution whereas the repair times comply with the Weibull distribution, and (c) the repair rate of failure is increasing, thereby implying that the maintenance staff expertise increases with time.

The Value of Flexibility in Make-to-Order Systems: The Effect of Demand Correlation

We consider a manufacturer of mass-customized modular products who orders components under demand uncertainty, and sets prices, produces to order, and trades excess components in a secondary market after this uncertainty is resolved. The sequence of events reflects, in a parsimonious fashion, the considerable reduction in demand uncertainty between the procurement stage and the selling season, typical of industries with long supply lead times and short product life cycles. We prove that, in contrast to conventional wisdom, the value of production flexibility and expected profit increase with demand correlation if, and only if, commonality between the corresponding products does not exceed a threshold. We also prove that the value of flexibility and expected profit may each increase or decrease with demand variability, depending on demand correlations and component commonalities across the entire product line. Finally, we prove that when demand shocks are independent, the optimal product prices are positively correlated if, and only if, the degree of commonality between the corresponding products exceeds a threshold.

Reliability and Maintainability Analysis of Bread Production Line

The statistical analysis of the bread production line of the failure and repair data at machine and line levels was displayed. The experiment covers a period of twenty-five months. The best fit of the failure data between the common theoretical distributions was found and its parameters were computed. The reliability and hazard rate modes for all machines and the entire production line were calculated as well. The models could prove to be a useful tool to assess the current conditions, and to predict the reliability for upgrading the maintenance policy of the production line. It was pointed out that (a) the availability of the bread production line is 90.74% and went down to 86.76% because the equipment's failures cause an additional production gap in the line, (b) the 53.5% of all failures occurred at the bread machine, cooling tower machine, and volumetric-divider machine, and (c) the machines of the bread production line that displayed increasing hazard rate functions were identified. This analysis will be very useful in terms of identifying the occurring and latent problems in manufacturing process of bread and improve it.

Testing Research of Liner Stress in Process of Side Pressing

Liner is key parts of equipment of slab side pressing, its main function is supporting the weight of lateral pressure, and are under some impact pressure, which is impact force up to 2000 tons, it make liner frequent breakage in the process of working, an led to entire production line stop, seriously affect the yield and efficiency of hot rolled strip. In order to obtain the reasons of liner fracture, the means of non-linear finite element and test combination were used to test and verify the correctness of finite element model, it is a new solution on how to settle liner breakage by calculation and analysis. The result of study indicate that it can effective increase the output and reduce the cost of cut end for hot-rolled strip, and has obtained the anticipated effect.

Simulating the factory

Its not just component that are now simulated and tested in software, but as well as the entire production lines and factories are also simulated before any hardware is built. The losses are not the only cost that has manufacturers turning to simulation tools for insight into how production processes can be improved.

A case study of investigating reliability and maintainability in a Greek juice bottling medium size enterprise (MSE)

The reliability and maintainability analysis of an automated mechanical equipment of juice bottling industry for a period of forty-five months at machine, workstation and entire line level was made. The descriptive statistics of failure and repair data, the identification of the most important failure modes, and the determination of the theoretical distributions parameters that best fit to failures data was carried out. Furthermore, the reliability, maintainability, failure rate, and repair rate models of the production line for all workstations and the entire production line were developed. The models could prove to be a useful tool both to assess the current conditions and to predict the reliability for upgrading the operations management policies of the production line. It was pointed out that (a) the availability of the juice production line is 85.66% and the efficiency amounts to 82.10% because the equipment’s failures. (b) The WS 1 and WS 4 display the most frequent failures and the lowest availability with 94.54% and 96.13%, respectively. Moreover, they show the largest number of different failure modes of the production process due to the complexity of the equipment with 28 and 30 different failure modes respectively. (c) In the production line, a failure occurs every 12.5 h or equivalent to two-failures per day approximately, whereas the mean TTR a failure is approximately two hours per failure. (d) The production line for the TTF follows the Weibull distribution, while the TTR follows the lognormal distribution. This particular methodology can also be utilized in the bottling industry sector by the machinery manufacturers and the manufacturers of bottled products to improve the design and operation management of the juice bottling production line.

On The Upside: A Decade of Growth and Innovation [Industrial Activities

The robotics community might have defined success in transforming our world in terms of the appearance of real products that perform robotic-assisted surgery or automated warehousing or intelligent toys. Now that the time is up, we can look back and recognize that these products did appear, and the markets chased by the companies seem to be robust. In all cases, the numbers are most easily expressed in billions. Global markets valued in billions have emerged and some companies, whose entire product line is robotics, are raising a good fraction of a billion dollars every year. Therefore, despite the short-term pessimism that drives the erosion of stock prices around the world, it seems that a little long-term optimism is in order. Indeed, however long it takes for the global economy to recover its vigor, the next decade of commercial activity in robotics is likely to be as innovative and surprising as the last.

To Protect and Serve

To Protect and Serve

Research Note—Price-Matching Guarantees, Retail Competition, and Product-Line Assortment

Price-matching guarantees (PMGs) are offers to match a competitor's price on a specific item. Such guarantees are extremely common in U.S. retail practice, and their impact has been studied in several published papers. The existing analytic literature models each retailer as a single-product seller; most work assumes that each retailer's product is identical with (or completely substitutable for) the competitor's product. In reality, competing retailers often sell multiple products, and these products do not always overlap, or may overlap partially but not totally. Furthermore, retailers that offer PMGs routinely exclude certain offerings from PMG coverage. This raises the interesting question of how product variety and product-stocking factors affect retailer decisions about offering PMGs. In this paper, we simultaneously consider three factors of retailing importance that imply results consistent with PMG use and nonuse: the ability to choose to stock the same product as, or a product differentiated from, a competitor's offering; the possibility of shelf-space limitations on the ability to stock complete variety; and the category-demand-enhancing effect of variety. These are sensible and realistic descriptive factors shaping retailers' product and pricing decisions, and because they have not been considered jointly in the prior literature on PMGs, their joint consideration helps to expand our understanding of the drivers of PMG implementation and impact. In the presence of these three factors, we examine retailers' decisions about whether to offer a PMG, what product(s) to stock, and how to price the product(s) stocked. Our results show that shelf-space limitations have an important influence on PMG provision: in particular, when retailers are shelf-space constrained, and product substitutability in the category is sufficiently large, choosing to use PMGs (which by definition also requires stocking identical products) is strictly less profitable than enduring Bertrand (price) competition but enjoying retail product differentiation. The result that PMGs can be profit-reducing relative to head-to-head retail competition is a novel one, driven in our model by the opportunity costs of stocking identical products, i.e., the inability to benefit from the demand-enhancing effects of variety and the differential (small or large) between Bertrand pricing and PMG pricing levels. We further show that under asymmetric shelf-space availability, either product variety will be severely limited or retailers will offer a different array of products. Weak substitution between products leads to the latter, with pricing between the differentiated products Bertrand and monopoly levels; strong substitution leads to the former, with pricing at the monopoly level. Our results also show that with unlimited shelf space, both competing retailers offer PMGs, stock the entire available product line, and enjoy monopoly pricing. Given our focus on product variety issues, we also relate our results to the literature on branded variants. Our results demonstrate that the nature of product variety, the availability of retail shelf space, and the category-demand-enhancing effect of variety are key market characteristics that jointly and strongly affect the optimality of PMGs and the resulting pricing and profitability characteristics of the market.

Keynote Address—The Innovator's Prescription: An Examination of the Future of Health Care Through the Lenses of Disruptive Innovation

Keynote Address—The Innovator's Prescription: An Examination of the Future of Health Care Through the Lenses of Disruptive Innovation

Reliability and maintainability analysis of cheese (feta) production line in a Greek medium-size company: A case study

Reliability, availability and maintainability (RAM) analysis of the cheese production line over a period of 17 months was investigated. The best fit of the failure and repair data between the common theoretical distributions was found and the respective parameters were computed. The reliability and hazard rate modes at the entire production line were calculated as well. The models are anticipated to be a useful tool to assess the current conditions, and to predict the reliability for upgrading the maintenance strategies of the production line. It was found out that (a) the availability of the cheese production line is 91.20% and went down to 87.03%, (b) the dominant four failure modes have the 62.2% of all the failures of the cheese production line, and (c) the average of a failure is every 12.5 operation hours and the mean time to repair is 66 min. This analysis will be very useful in terms of identifying both the occurring and latent problems in cheese manufacturing process of and, eventually, solve them.

Modes in component behavior specification via EBP and their application in product lines

The concept of software product lines (SPL) is a modern approach to software development simplifying construction of related variants of a product thus lowering development costs and shortening time-to-market. In SPL, software components play an important role. In this paper, we show how the original idea of component mode can be captured and further developed in behavior specification via the formalism of extended behavior protocols (EBP). Moreover, we demonstrate how the modes in behavior specification can be used for modeling behavior of an entire product line. The main benefits include (i) the existence of a single behavior specification capturing the behavior of all product variants, and (ii) automatic verification of absence of communication errors among the cooperating components taking the variability into account. These benefits are demonstrated on a part of a non-trivial case study.

Reliability and maintainability analysis of strudel production line with experimental data – A case study

The strudel production line consists of several workstations and machines in series supplied with a common transfer mechanism and control system that have different failure modes. When a random failure occurs, the failed machine stops and forces most of the line upstream of the failure to operate without processing whereas the material (raw, intermediate or end-product) of the line downstream may have to be scrapped due to quality deterioration during the stoppage. The failure impact is the drop of line reliability and production rate. A reliability and maintainability analysis of strudel production line at machine, workstation and entire line level was developed. Descriptive statistics of the failure and repair data was carried out and the best fitness index parameters were determined. Data collection from production line and their analysis were valid for a period of sixteen months. Furthermore, the reliability and hazard rate modes for all workstations and the entire production line were calculated. The proposed models could be a useful tool towards (a) assessing the current conditions, and (b) predicting reliability for improving the production line maintenance policy.