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Production/Operations Management - Science topic

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As research on systems for drone delivery of small packages continue, a possible urban asset to successfully leverage is the network of natural and man-made drainage in metro areas.  This inventory would include streams, waterways, canals, gullies, rivers.  Has there been any empirical work been done on utilising these networks for commercial delivery of packages by drones.
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Textbooks about the managerial aspects of Digital Transformation and Industry 4.0 for academic teaching with exercises and case studies.
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Perhaps look to good articles … for a book it is not yet the time
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In the last month’s record if output=Rs. 20000, human input=Rs.10000, material input=Rs.2000, capital input=Rs.1000, energy=Rs.500 and other expenses=Rs.1000, calculate total factor productivity.
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To what do you want to use the total factor productivity? Calculation is easy , but as Simon (1979) and others have shown, Cobb-Douglas (or CES) production functions are fake ones. They represent accounting identity as something that represent production relations (input-output relations). We should doubt all arguments based on TFP such as Solow-Swan growth theory and more refined Romer-Lucas endogenous growth theory.
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to create precedence Diagram as you know we have to calculate forward pass and backward pass  which is ES,EF LS and LF
so early start will be either 0 or 1 which one do you think is correct and why?
if you say Early start 1 why and if you said 0 why?
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ES=0
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MICLASS and DCLASS coding system in group technology follow which type of coding: monocode, polycode or mixcode? Why Opitz classification and coding system is a mixed code. I can understand that there is the feature of polycode, but I cannot find any feature of monocode or hierarchical order in Opitz coding system.
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Sorry for the very very late answer (I saw this question now only).
This article has list of references that answer your question "Feature extraction from STEP (ISO 10303) CAD drawing files for metalforming process selection in an integrated design system"
The article is available on researchgate
please refer the references listed in it
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In the laboratory I’m working at, we are conducting a research about Lean tools use in each phase of DMAIC method. It would be very important for me if you can help me by answering the following survey.
It would take you no more than 5mins.
You can access in the following link:
Thanks
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Hi Diana Cardenas is there any update on the research. I would be interested in reading your findings. Best Regards Martin
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Cycle counting
i) is a process by which inventory records are verified once a year
ii) provides a measure of inventory accuracy
iii) provides a measure of inventory turnover
iv) assumes that all inventory records must be verified with the same frequency.
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Dear
Cycle counting of Inventory is using in Industries for some of the other purposes
It for ----- How many time This inventory in the organization , what is consumption resio , what is value impact on the organisation , through this we can reduce
1-: inventory carrying cost .
2-: Inventory testing Cost
3-: and avoid to product manufacturing or supply loss
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I am currently testing a model that involves cross-level interactions. The dependent variable (corporate financial performance, a formative scale) and the independent variable (corporate sustainability performance, a formative scale) are measured at the firm level, and the moderator is a country-level variable. What software and/or statistical package can evaluate this model? I feel that I need a tool that combines the strengths of PLS and HLM.
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As far as I know when usinh formative scales one cannot use efa cfa chronbach and sem
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I need an article, paper, book, etc. for mixed or multi-model of assembly line problem. However, any article related to multi-objective ALBP is very useful for me too.
Obviously, the difference between the mixed model and the multi-model line is the batch sizes defined for various types of products in multi-model ALB.
Regards,
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Dear Nima Pasha,
I recommend an article that describes the solution to a mixed or multi-model pipeline problem.
V. E. Lelyukhin and O. V. Kolesnikova, "Strategy for the Formation of Production Plans for Small-Serial Machine-Building Enterprises," 2019 International Science and Technology Conference "EastСonf", Vladivostok, Russia, 2019, pp. 1-6. doi: 10.1109/EastСonf.2019.8725334
Regards,
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if you sell umbrella, you have two season, one where is high seasonal demand and the other one is the low seasonal demand. How do you estimate when and how much the optimal order quantity is, if you know the one season will be end soon, so u know u cant sell all product (assume the amount is as large as EOQ) on the season, and the remain must be sold on the next season?
thank you
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Again, greetings to all the esteemed colleagues who are followers of this question. Last week I submit to the Research Gate platform, the Spanish version and the English version of the work: Multicriteria models to evaluate social development projects [New version], what we assume may be in the interest of all of you.
I apologize to those who receive this information multiple times, since I am sending it to several questions related to the subject.
Thank you for your attention and I hope you find the information useful.
Best regards,
José Herández.
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In CRS model, the input and output oriended objective function values are reciprocal to each others. But why not in VRS?
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It is not sufficient to attribute it just to the difference in the orientation between the CCR and the BCC models since "maximizing the outputs subject to the given inputs" and "minimizing the inputs subject to the given outputs" under CRS assumtpion provide reciprocal efficiency scores. Thus, we firstly have to consider the additional free in sign variable in the multiplier BCC model and the additional constraint about the lambdas (Σλ=1) in its envelopment counterpart. This changes the shape of the frontier (BCC efficient frontier) and allows, besides CRS, for increasing and decreasing returns to scale. The above, in conjuction with the orientation that guides the projections, provides non-reciprocal efficiency scores between input and output orientation under VRS assumption.
For a schematic represenation of the above check the attached image.
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What are the differences among flexible manufacturing system (FMS), computer integrated manufacturing (CIM) and totally integrated automation (TIA)?
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The three phrases (names) reflect the shift of attention on various features (functional flexibility, information-based integration, supervised automation) of evolving complex production systems, which may largely differ in terms of their scale and practical implementation. On the other hand, largely different interpretations can be found in the literature and in the practice.
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Which is not an essential requirement of JIT purchasing?
(i) Stable relation with vendor
(ii) Simple purchase agreement
(iii) Timely exact quantity delivery
(iv) Specifying all conceivable design features
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Agree with Rai Waqas Azfar Khan all are important.
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Is there specific KPI(s)?
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Demand variability is a measure of how much variability there is in customer demand.  It is the difference between what one expects to happen and what actually happens.  Demand variability is driven by several factors including:
  • The complexity of demand in general
  • Variation of demand across global enterprises
  • A lack of visibility within and across supply chains
  • Variable forecasting approaches at both the plant and customer level
  • Variable lead times at both the plant and customer level
  • Increasing inclusion of more suppliers and subcontracts
  • Increasing inclusion of smaller suppliers
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In which phase [Initiation, Planning/Design Phase, Execution and Closing] of a project, project appraisal is conducted to accept or reject a project?
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Hi...
Adis is right.
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Which of the following is not a component of inventory carrying cost?
i) capital cost
ii) transportation cost
iii) insurance cost
iv) obsolescence cost.
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transportation cost
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The implementation of JIT offers several advantages, including
(i) work-in-process increases
(ii) rework reduction
(iii) decreased profit margins
(iv) increase in variability to better respond to variable demand.
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Which advantage JIT offers?
Is JIT refers to Just In Time? If yes agreed above points except "decreased profit margins" - why JIT decreases profit margin? Is it because JIT can reduce production cost & hence the product can sell at lower price for better competitive strategy?
Think another advantage includes reduce or minimal warehouse / storage cost of finished goods.
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I am looking for any articles focused in the topic of Scheduling in Hybrid Flow Shop systems, using Ant Colony techniques. Also, if anyone have any articles in this matter that include the scheduling of systems that involve Make to Stock and Make to order products.
Thank you
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This article may be useful for you.
Best regards
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Hi
I would like some advice and hopefully references to papers or other sources that have researched warranty or failure forecasting methods.
Especially when a current component is replaced by a new. Event and warranty history of the current component is available. What possibilities are existing in the research/applied community ?
I'm particularly interested in applications in the automotive domain, however general advice is appreciated as well.
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Great, thanks!
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We have many assumptions when we optimize the production scheduling based on the flow shop sequence model, and omit an important factor about human beings. The schedule may not turn out as we planned due to the thinking and behaviors of labors or managers. I want to consider the impacts of human but have no idea about the methods. Could anyone provide some suggestions or related publications? thanks!
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您好!
I consider that it would be a good option to use a wider communication, form may managerial experience, sometimes, if you do not communicate (in an easy way) your objectives to your operators (workers), it is very difficult to have a good performance on any initiative or project you want to implement. So, depending on the educational level, you need your workers to understand what, how, when, and/or who will work on the initiative or project. Once you have cover that request, you can use any abstract tool to approach the reality.
祝好,
丹尼尔。
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Interesting project - reminds me of the problems I faced when forecasting sales when scheduling production - there I tried to do several things to reduce the impact of uncertainty.
1.      Apply effort to reduce the uncertainty associated with the most important items.
2.      Separate uncertainty into those where I could improve my knowledge of the item (sales trends and seasonality) and where I could not improve my knowledge ("random" fluctuations due to weather etc.)
3.      Improve "agility" appropriately (so as to speed response) when actuals differed significantly from forecast - holding inventory at a sub assembly level, buffer stocks.
4.      Flag and investigate situations where the actual was an outlier - such as a customer changing the product that it bought routinely (despite sale saying that this was a purely random blip!!).
Also, I think that the quality management knowledgebase may be a good source of ideas.
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EITHER 1. Make your response adaptable to change
OR 2. Make your response resilient to change
then you are proof against uncertainty
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I have the maintenance cost for each individual  HEMMs. I want to know if I can use simple moving average, weighed moving average or exponential smoothing methods to calculate maintenance cost for future projects and also to decide whether it will be more profitable to go with old vehicles or buy new ones.
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Usually moving average chart used to monitor process variation. I think the best tool is time series chart.  
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We have a Mixed-Integer Non-Linear Problem with square root components on the decision variables. I have seen a proposal to reformulate as a Conic Quadratic problem, but I am not sure if this reformulation guarantees optimality with respect to the original problem.
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There's a script of Ben-Tal and Nemirovski on convex optimization that also has a chapter on conic programming. It's my first reference and I can really recommend it: http://www2.isye.gatech.edu/~nemirovs/Lect_ModConvOpt.pdf
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National Furniture Company (NFC) is the manufacturer of home and office furniture. Currently they are in financial crisis and after an inquiry it was found that the problem occurred due to inaccurate demand forecast. The sales manager, who is responsible for the demand forecast was also contacted for explanation. At the other hand sometimes organizations have to spend huge money in holding the inventory which ultimately brings losses to the company.
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As a production manager, i will guide to sales manager to follow some steps as mentioned below-
1.Observe the demand of last 6-7 months.
2. Accordingly plan the material which has regular demand.
3. Do not stock the undemanded product.
4. Observe the market scenario and potential also.
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The above query relates to the Production & Operations Management,which is a functional area of Management
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Hello,
The advent of Internet of Things (IoT) has resulted in creation of Smart or Intelligent Products. IoT affects the lifecycle of such products greatly and causes a new approach tp Product Lifecycle Management which is known as " Closed-loop Product Lifecycle Management". This can be listed as the newest research trends in this field.
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I search the way to make one complex parameter for significant impact of new production equipment: investment cost of machines and tools, quality, throughput, capacity scalability, number of product types, system conversion time, stability, maintenance, ...
I would be glad to find out other existing Procedure or Ideas.
Are there any references for this topic.
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Hello again Edin,
thank you for providing me with your clarification.
I can tackle your question from two levels.
The first one, more specific, pertains a suggestion of a single indicator already existing in common practices.
The second one, on a general level, sees suggestions of methodologies to come up with a single indicator which may suit your need. 
When it comes to the first level, I do also agree on the use of OEE, provided that understanding the impact of equipment availability (maintenance), efficiency and production quality on the overall equipment effectiveness is interesting to you.
I have also developed an "energy version" of the OEE which assesses the impact that these three factors have on the total energy consumption of the equipment. You may find the paper on this in my publication list on RG (Winter Simulation Conference 2014).
When it comes to the second level of my suggestion, I also agree on the use of methods for Multi Criteria Decision Making (MCDM). I have attached a file explaining the methods of it, done by the Department of Communities and Local Government in London. It addresses a policy maker audience, but I do believe that it did its job well even for other types of users.
Hope this may help you out!
BR
Ilaria 
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I am analysing the route that spare parts follow in a manufacturing plant, and I should determine the costs deriving both with availability (i.e. stock costs in warehouse) and unavailability (i.e. the costs caused by the lack of the products themselves)
The total cost should comprehend both the two costs (stored and missing materials), but the second term is particularly difficult to identify.
Could you please suggest me an approximate way to calculate it? Is there a correlation, for example in terms of percentages of the unitary cost?
Than you in advance
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Hi, good day to all ResearchGate members,
I would like to know how to calculate the time covariate in cox regression.
My data is about companies which produced product A and product B. The time of production of product A/B is different for each of the companies. These companies are subsequently default/distress after the production of product A/B. I selected the default/distress time as the 'death time'. Then later I collected the data 5 years backward, i.e. 5 years before the 'death time' for observation period. Within this 5 years of observation, there are companies which produced the product at year 5th ,4th and 3rd. In other words, some companies have observation 2 years before 'death', some with 3 years of observation and so on. How to calculate the time covariate then? And how to set up the data in excel?
 I hope my explanation is clear. Appreciate your feedback.
Thank you.
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Dear Stephen DeLurgio,
Thank you for asking. i was wondering how the data input should be key-in if the data (independent variables; IV) involves unbalanced panel data? Should I take the average of the independent variables for each of the survival time?
Using your example in previous posting for Company A:
Says, in Excel:
Time   IV for X      IV for Y
0           X1              Y1
0           X2              Y2
1          X3              Y3
Is this the right way?
Appreciate your feedback. Thanks
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This question is about naming.
I am struggling to find out whether a name exists within the field of operations management research in order to address such an "approach" explained as follows:
  • you have a production system (even a simple equipment) as your base case (let's call it BC);
  • you plan to invest in a new configuration of your production system, or simply to change its operations --> you model one or more possible design alternatives (let's call them C1, C2, etc)
  • you define the performance indicators you will use to compare BC, C1, C2 (can be economic, environmental ones)
  • you model how these systems may work, calculate the indicators and compare the alternatives. 
Any references, if well-connected to this topic, are most welcome.
Thank you in advance
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You can study  the PROMETHEE for   multi-criteria decision making . It will help you.
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There is a problem with simultaneous variation of the structure (production equipment) and variation of parameters for each equipment (variation of processing time, reducing time of services, Increasing of priority of working place, ...) by using Design of Experiments .
My suggestion is that we first varies structure in dependence of production cost and achieved annual production. After that we choose best ranked structures for process of parametric optimization.
I would be glad to find out other Procedure or Ideas.
Are there any references for this topic.
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Dear Edin,
Firstly, please correct your question. DOF is wrongly written instead of DOE. It helps you to find better answers.
One of the advantage of DOE is its ability to analyze the simultaneous effect of different factors on specific outputs. In your case,  I recommend to use a scenario-based design. You can firstly consider the existence of variation in each equipment and then go through the final design. Alternatively, you can consider these different scenarios to check which equipment has the most significant effect on you model responses. Finally, you can use some weighting approaches to involve and change the weight of these different scenarios in you final decision.
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Especially in the Moissac - Montauban region in south-west France, there is a significant fruit hub. For example, Tarn&Garonne is one of the major region for apple production in Europe and welcome the biggest apple exporter in France, Blue Whale. 
I know general papers about F&V supply chains in Europe, like recent European Parliament paper by Bijman, but I know no study focused on south-west France supply chains.
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Currently, I am teaching a subject about operations management and I have to introduce to my students the importance of safety stocks and the different ways to determine it. At this point, I was analyzing how this issue is explained in operations management books, and I realized that some of them compute the safety stock on the basis of the lead time demand distribution (Heizer and Render,  2008), whereas books more specialized in inventory management (Silver et al, 1998) and (Nahmias, 2004), they suggest to use the lead time forecast demand error distribution.
I think that we should use the lead time forecast demand error, what do you think?
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Dear Juan, I think that it is more correct to consider the forecasting error distribution instead of the demand distribution (during lead time). The two alternatives would be equivalent if you use, as forecasting method, the simple mean over all the hystorical data. In this case the estimate coming from the forecasting method is exactly the mean value of the demand during the lead time.
But if you use any other forecasting method (like moving averages, or exponential smoothing) to estimate demand during lead time, your estimate will be different than the simple mean over the periods. Because you use a forecasting method to estimate demand during lead time, you have to protect against errors in forecasating demand. This is why you have to consider the standard deviation of forecasting errors to calculate the required safty stocks.
In summary, the books that consider standard deviation of demand instead of s.d. of forecasting error do not consider the link between inventory control and forecasting method.
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Three specifications:
  • the impact assessment occurs within the design stage of the system
  • for "production system" I mean not only whichever manufacturing system, but also systems for end-of-life processes (e.g. disassembly, recycling)
  • the impact is with respect to sustainability, hence, economy, environment and society.
Many thanks.
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Hi Ilaria,
Kassu already send you an extended lists of possible sources.
From a Quality point of view, I do like very much the APQP Automotive Industry Methodology: QFD, Product FMEA, Process FMEA; MSA, Process Capability Study/SPC study, Control Plan. It should assure that your process in under statistical control and has a good process capability to deliver quality product to the customers (a bit heavy methodology for many organizations, but …).
Environmental speaking, there is an ISO standard for this purpose: ISO 14044, Environmental management — Life cycle assessment — Requirements and guidelines. However, in my view, many times you do not need to do a full LCA, a simple consideration of the life cycle stages which can be controlled or influenced by the organization might be sufficient. For this purpose the organization may obtain this information directly or seek it from the supplier of the products and services. Information already developed for regulatory or other purposes may be used in this process. Typical stages of a product life cycle can include, for example, extraction of raw materials, design, production, transportation, use, and end-of-life treatment. The life cycle stages that are applicable will vary depending on the activity, product or service.
SA8000, available for download at Social Accountability International web site (http://www.sa-intl.org/) might be of interesting to you for social impact and they have good lines on how to interpret and apply it.
And if you want to make it really summarized, why not use CANVAS strategic model (1 page, available at http://www.canvaslms.eu/).
I used a model to research the influence of Sustainability/CSR programs in Organizational success (mediated by stakeholders satisfaction) for my PhD Thesis (framed on Stakeholder Theory and RBV) but looking back, it is a very heavy and quantitative demanding approach and is written in … Portuguese.
I wish you the Best.
Luis Fonseca
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I would like to conduct empirical research on the effectiveness of certain operational practices on the different quality dimensions: production quality, product quality, product reliability etc. Does anyone know a validated construct that could be used?
Thanks a lot for your help!
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Dear Niklas, 
I think one the problems we face when trying to answer your question is that there are several definitions for Quality Construct with multiple dimensions: The Gurus definitions, ISO 9000 International Standards Series, Excellence Awards, and so on. So, I do not think there is one single scale applicable to all models and industry scopes.
Powell, T.C., 1995, Total Quality Management as Competitive Advantage A Review and Empirical Study, SMJ, Vol. 16, No. 1. pp. 15-37, is a classical for TQM measurement.
For B2B I think the Crosby definition of conformity to standards still applies many times. For B2C I would ask customers if they would recommend the service to a friend and if I get 8 or more in a 1-10 Likert scale I would be fine.
There are indeed some articles that propose specific scales for specific situation, e.g.., for services, SERVQUAL service quality model Parasuraman et al (1985, 1988, 1991) is commonly used. It highlights the main components of high quality service. The SERVQUAL authors originally identified ten elements of service quality, but in later work, these were collapsed into five factors - reliability, assurance, tangibles, empathy and responsiveness - that create the acronym RATER. SERVPERF is another scale that claims can be used for this purpose (Sanjay K Jain and Garima Gupta, VIKALPA • VOLUME 29 • NO 2 • APRIL - JUNE 2004, available at ResearchGate).
So, in summary, my advice would be to be more specific and try to find out or create and then validate your own scale for the specific construct and research you pretend to carry on.
All the best
Luis Fonseca
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Advances in different areas are often offloaded into education. One concept that is currently being peddled in different areas is lean management. Outside of theorising, are there specific areas in which the principles of lean management can benefit education? Do the central principles of lean management converge with the goals of education or do they stand divergent to it? Does it bring a one size fits all scenario? Please let's have your views
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Hi, Gordon:
This has been a perplexing issue for many in education! Perhaps because of  problems in understanding, communicating and transferring lean thinking in the education context!
For example, a recent research study (Bessette, 2012) argued that principles, management, and leadership tactics within standards of businesses recently have proven to become nonconforming in terms of education which prevails and is exercised in businesses!
The author goes on to argue that simplistic operations techniques which have been used and nurtured in the past three decades have shown to become obsolete in terms of the new visions and focuses on realistic goals and plans within companies and organizations.
Furthermore, the author argues that sustainable methods, with the increased concentration in operations management techniques, have proven to be useful and educational in terms of task completion. When companies, associations, and organizations plan and show significant impacts on environments, ecosystems, and societies, they have the ability to enable humans to significantly help improve the surrounding educational methods towards businesses!
Very interesting research. please take a look at it:
  • Bessette, D. (2012). THE MANAGEMENT PROCESSES: UTILIZING LEAN THINKING AND SIX SIGMA [6σ] TECHNIQUE EDUCATION IN SUSTAINABLE METHODS. Review Of Management Innovation & Creativity, 5(14), 69-73.
Hope this helps!
Nadeem
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In operations management, business organizations offer either product or service. Can we consider healthy practices as non-product medicine?
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If food is medicine, then healthy food, exercise and fresh clean air and water may be regarded as 'medicine' in that they contribute to health.  I am reminded 'Let thy food be thy medicine.'
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For ex: according to literature
Economic dependency between units implies that performing maintenance on several units at the same time costs less money and/or requires less time than dealing with each unit separately.
while Structural dependency refers to systems where several units form an integral part, so that maintenance of a failed unit also demands the treatment of other units in the part.
is structural dependency not economical?
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I am not an economist, but in software we have something similar to this. It is always best to have your code modular so that when you have to correct something, you can do it cirurgically, without having to worry about other pieces of code. You can also operate the maintenance of two pieces at the same time if you are changing one while the other one is running (as a test for what you changed before)
To me structural dependency comes as a cost, or an increase in costs, because when you want to maintain unit 'a', which has a cost 'ca' , the structural dependency forces you to work also on unit 'b', and you end up with a total cost of 'ca+cb-y', which is '2ca-y' if the cost of maintaining each unit is the same. 'y' with y<ca is what you save from simultaneously operating on both units. I say that overall, structural dependency comes as a cost because '2ca-y' is bigger than 'ca' (original expected cost)
Economic dependency is the opposite. It comes as savings. You want to maintain units a and b, which would normally cost you '2ca' under the same assumptions, and you end up saving 'y' because you operate on both units at the same time. Therefore the total cost comes as '2ca-y' which is smaller than expected ('2ca').
Another way of seeing the difference is that with structural dependency (sd) and economic dependency (ed) you end up having the same cost, but if you notice, in one case you were just trying to maintain one unit (sd) and in the other you were planning to intervene in two units (ed). So, ed is cheaper than sd.
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Many researchers argue that EDI (i.e. Electronic Data Interchange) technology does not provide flexibility, arguing that EDI is out of date technology. To what extent is this claim valid? To which industry sector to this valid? What is the alternative?
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Intranet technology is already adopted by most of the system suppliers. The new trend is to use Enterprise Content Management Systems for sharing not only of documents but sharing of real-time dynamic production data. A good approach is to extend the existing functionality of existing CMS (like SharePoint) with additional Manufacturing Operations Management (MOM) functionality, such as ISA 95 objects, OPC, BAPI, etc.  
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Generally for service level calculations most of the papers used cu/cu+co.
I felt it is applicable to only stochastic problems. Can we use this formula for a deterministic problem?
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Since we are using the same number of periods for sales and demand, it does't matter whether you use total sum or average in calculation of fill rate.
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A newsvendor simultaneously faces two risks - that of stockout and excess stock. A newsvendor who orders less than optimum is averse to having excess stocks but is taking risks of stockouts. Similarly ordering more than optimal could mean being risk averse towards stockouts but risk taking towards excess stocks. How should then a risk averse newsvendor be defined?
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A good source to start with is certainly Schweitzer and Cachon (2000) who discuss several utitliy functions (preferences) such as risk aversion of newsvendors. The key is to define the utility function appropriately and then to optimize expected utility instead of expected profits.
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People in business and research scholars are familiar with the term “economies of scale.” But in the present era of chaotic competition, It is now believed that this term is largely being replaced by the term, “economies of scope.” I wish to know all the possible and detailed features of the term “economies of scope” and how it actually works.
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Anu you are talking about economies of scale. I was curious to know about 'scope'.
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It is believed that in the sphere of production system the paradigm is shifting from Fordism to post-Fordism, but a full comprehension of this concept is not quite clear. What all are the features of the Post-Fordist production system, and why is it also called Toyotism or flexible specialization? Any suggestions?
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In the modern context with widening market preference the necessity is to have a large variety of products. Obviously with a large variety of products, the life of the product is limited as well as the volume. This means modularization and standardization is necessary in order to reduce the product development time and cost. In this scenario, the economy of scope (variety) is more relevant than economy of scale. For this purpose one requires flexibility of products and flow manufacturing. They require multi-functional machines and control in real time.
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Hello, I am searching for mathematical equations expressing processing time (and quality) as variable dependent on the load (jobs/resources) and overwork (fatigue) in the system, i.e. as load increases operators speed up (or cut corners with an impact on quality); if high levels of load are maintained for a longer period, fatigue sets in, thus operators lower their speed (bellow normal levels) and quality (potentially) deteriorates as well.
Relevant papers found so far:
- KC, Diwas and Christian Terwiesch. 2009. "Impact of Work Load on Service Time and Patient Safety: An Econometric Analysis of Hospital Operations," Management Science. 55(9) 1486-1498, -> the authors build regressions models of processing time and quality (difficult to replicate given the number of observations required)
- Cutting Corners and Working Overtime: Quality Erosion in the Service Industry
Authors: Rogelio Oliva, John D. Sterman, Management Science, 47(7), July 2001, 894-914-> system dynamic model based on more than 30 equations
thank you!
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My knowledge regarding this problem is Systems Dynamics based and I also looked at the Oliva/Sterman paper. To me it is still the best model for overtime, wear-out and quality. It can be described as a state-space model, instead, and one may eventually obtain analytic solutions from that. Such systems tend to have under damped oscillatory behaviours.
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I am just asking about, "Suppose we have a production line that consists of 12-14 works stations and our objective is to enhance the productivity of the operations by eliminating the time losses due to less effective man and machine utilization." So, suggest a plan or set of Management tools that will help in carrying out improvements in the the system.
Thanks
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Mr. James Cock
I have read and analyzed your answers and what I understand is that
From 1st Answer
-Organizations, most of the times waste their time and resources in misguided improvement efforts.
-It is better to have a system for identifying different alternatives and then to check which alternative would be more effective.
- In a production Line, production sequence and location of constraint play a vital role.
- It is better to have constraint at the end of the line
From 2nd Answer
-Production line starts from suppliers and ends at the market or customer demand instead of only work stations
-The production systems work mostly on stochastic distributions
- My concept of work center efficiency was wrong because efficiency of the constraint sets the efficiency of the production system
-If we try to trim the capacity of the non-constraints then it will Cause deficiencies of supplies on the constraints and eventually the efficiency of the whole system will lower.
Sir, I want to know, whether my interpretations are right or wrong? And Sir, kindly refer me some helpful material for understanding Discrete Event Simulation.
Thank you
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Does anyone know about free data sets available for research purposes in the field of production and operations management?
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Dear Luis, I don't think there are, since OM has 'unlimited' issues. Which data or idea you need (sequencing, scheduling, etc), I'll possibly suggest the link or published paper.
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Functional strategies have important roles in achieving business strategies. These strategies affect each other in many situations and in different ways. In absence of good correlation between them we can't do the best. Thus, we must find appropriate methods for achieving a good correlation.
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I would echo that. This can be critical in directing higher level managers towards tactics that align with overarching strategies. See "The efficient use of enterprise information for strategic advantage: a DEA analysis"
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Faced with a global marketplace characterized by a growing competitiveness, and higher expectations from customers, organizations are more and more under increasing pressure to demonstrate their status as corporate suppliers with good quality management systems, good environmental initiatives, good safety policies, among other practices. To meet such expectations, organizations are increasingly adopting integrated management systems based on internationally recognized standards. Research suggests that integrating management systems may provide significant advantages to organizations. Do you think that the healthcare sector may also benefit from such strategies? Why should healthcare institutions think about such options? Do you know any research paper(s) focused on such questions?
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The National Baldrige Quality Award Standard for Health Care is one set of standards for heath care organztions that has shown some positive benefits towards improving operations and achieving high performance benchmarks in patient care. See link for references: http://www.nist.gov/baldrige/baldrige-120412.cfm#