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Production Planning - Science topic

Everything in the field of production planning, methods, systems, IT and so on
Questions related to Production Planning
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Hello everyone,
I would be interested to know which trends you, as experts, see as future research topics or research fields in production planning and control. Gladly also with reference to literature or studies.
Do you see more focus on the application and testing of new algorithms, do you think more research is needed in terms of systems understanding, or do you even say that the research field PPC is fully explored?
Thank you!
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I think Production control enabled by digital visualisation with key insights for decision making would interest most production managers, whether they are on the floor or working remotely, they can access what is happening in real-time
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Such a system can be a Business Intelligence analytical platform connected to the Big Data database system, where information from the Internet is collected, collected, processed and analyzed, including comments from Internet users entered into social media portals.
On the basis of this data, analytics reports are created in the Business Intelligence system describing changes in interest, consumer preferences for specific products and services, as well as changes in the company's brand assessment that offers a specific product or service offer to the market.
These reports can be very tangible in the business management process, including they can support decision-making in the field of production planning as well as the distribution process, sales organization in the form via the Internet, in the form of e-commerce.
Do you agree with me on the above matter?
In the context of the above issues, the following question is valid:
How to build a decision support system in the field of selling on the Internet, online store, e-commerce?
Please reply
I invite you to the discussion
Thank you very much
The issues of the use of information contained in Big Data database systems for the purposes of conducting Business Intelligence analyzes are described in the publications:
I invite you to discussion and cooperation.
Best wishes
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Dear Gioacchino de Candia,
Yes, that's right. The issue of collecting and processing large sets of information on Big Data Analytics platforms is particularly crucial in the context of the discussed issues.
Thank you, Regards,
Dariusz Prokopowicz
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Dear Research Fellows,
It would be much appreciated if you can advice me what research papers or published books which discuss the artificial intelligence algorithms or math models for production planning optimization.
The input factors could be: production volume, list of production machines and their capability, materials, delivery schedule, production location Vs shipping destination, production cost....
The output could be an optimized production plan: which machines should be used for a specific order, taking production cost, shipping cost... into account.
Best Regards,
Duong
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Dear Dr
The following same books in the topic
1-Introduction to Computational Optimization Models for Production Planning in a Supply Chain
Springer
Stefan Vo?, David L. Woodruff
Year:
2006
2-Effective Resource Management in Manufacturing Systems: Optimization Algorithms for Production Planning
Springer-Verlag London
Massimiliano Caramia PhD, Paolo Dell’Olmo (auth.)
Year:
2006
3-Production to Order: Models and Rules for Production Planning
Springer-Verlag Berlin Heidelberg
Dr. ir. Nico Dellaert (auth.)
Year:
1989
4-Stochastic Modelling in Production Planning: Methods for Improvement and Investigations on Production System Behaviour
Gabler Verlag
Alexander Hübl (auth.)
Year:
2018
with best regards
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If any one can help me to Prepare " User requirement Specification " For Production planing and scheduling in ERP system
Thanks
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Does anyone know; is there any special formula for inspection or preventive maintenance intervals or scheduling, when we are applying the artificial neural network models instead of conventional methods such as weibull?
Thanks in advance
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I agree with Mohammad Asjad and Günter Becker . ANN is a prediction tool. If you have one or more equipment failure data, you can use Weibull distribution to analyze the failure.
Due to the Weibull distribution, you will be able to comment and create schedules about the behavior of the equipment and even the system.
Cost factor is the most important criterion in these scheduling. Thanks to the Weibull distribution, I suggest you take advantage of the relevant study below in order to determine maintenance periods about costs and failure.
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Hi all,
I'm studying on a production plan which consists of different vessels, tanks, distillation columns, switch rooms,.. and I need a reference to determine points which have critical safety conditions thus I could compare their risk level.
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Dear Fatemah,
FMEA (Failure Mode and Effect Analysis) could be one of the approaches to assess the criticality of machines or process. This approach is considering the severity, occurrence and detection rate. In the first, you need to identify the risk, in this process, you can do brainstorming with the production team. Next, you need to do risk prioritisation (using the multiplication of severity, occurrence and detectability) and you can find the machine or process that has critical safety conditions. Make sure to choose the respondents who really understand with the production process. As far as I know, there is no exact minimum number respondents.
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If will be nice if the dataset is in some form or spreadsheet or is a format that can easily transferred into an SPSS or Minitab.
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Can anyone help me with a dateset (SKU number, forecast data, actual data) for demand planning, which I can use in my research ?
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I am currently writing my master thesis in the automotive industry. It is an Action Research and the aseembly capacity for a certain component needs to be increased. There are two options to do that:
1) expand an existing assembly line where currently a similar part is assembled
2) invest into a completly new assembly line
I can't find relevant case studies or papers regarding this or a similar topics. Only some standard procedures from the fundamental literature about production planning. Do you know similar cases or papers about that topic?
I am looking forward for your response. Thank you in advance.
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Dear Anton Lorenz,
*****Assembly line production has become established globally in the automotive industry since its introduction at the Ford Motor Company more than 100 years ago. Companies with diverse product portfolio often face capacity planning problems due to the diversity of the products and the fluctuation of the order stream. High volume products can be produced cost-efficiently in dedicated assembly lines, but the assembly of low-volume products in such lines involves high idle times and operation costs. Reconfigurable assembly lines offer reasonable solution for the problem. Another I will suggest the implementation of a modular concept, the flexibility and changeability of car manufacturer’s assembly systems could be increased, and it may create an effective and efficient way to adapt the assembly system to the requirements of the future automotive industry. By this, the assembly system can handle the complexity of assembling cars in the future resulting from a further differentiation and individualization of products as well as an increasing dynamic of the markets.
An assembly line sped up is a dramatic manufacturing process (often called a progressive assembly) in which parts (usually interchangeable parts) are added as the semi-finished assembly moves from workstation to workstation where the parts are added in sequence until the final assembly is produced. The use of interchangeable parts allowed for continuous workflow and more time on task by laborers. Worker specialization resulted in less waste and a higher quality of the end product. It allowed factories to churn out products at a remarkable rate, and it also managed to reduce labor hours—benefiting many workers who used to spend 10 to 12 hours a day in the factory trying to meet quotas. As such, the development of the assembly line method in the Industrial Revolution sped up production and simplified the manufacturing of goods.
Refer site
1. file:///C:/Users/3020/Cookies/Desktop/Downloads/Capacity_Planning_and_Resource_Allocation_in_Assem%20(2).pdf
2. Ceryan O, Koren Y. Manufacturing capacity planning strategies. CIRP Annals - Manufacturing Technology 2009; 58(1) 403-406.
Ashish
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Can someone please suggest any material on branching process applications in manufacturing industry, production planning and control?
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Noha A. Mostafa I meant branching process (stochastic process) not the branching for MIP. Thank you.
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The 3 factors of machine remains constant MTTR ,availability(AT) and cycle time(CT), but the TH changes as the capacity and length of conveyor changes .factors like MTTR, availability(AT) and Cycle time(CT). the final output should be throughput(TH - Dependent factor).
The 3 factors of machine remains constant MTTR ,AT and CT, but the TH changes as the capcity and length of conveyor changes.
Can someone please help me if i can use regression analysis to find the equation that gives the relationship between 31conveyors and TH. so that if i change the value of conveyor i can find the value of the corresponding TH. The sample size wont be a problem as i will be collecting data from the simulation model.
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Probably But remember that all your variables including DV are measured with error. If you don't take that into account you loose accuracy. Build your prediction equation carefully. Graph everything and look at:
This is the optimal method. See the attached. Best, D. Booth PS you'll find a great R program at that link
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I also have question about Energy consumption, is there any way to find each product energy consumption?
Is the cost of Energy consumption increases by increasing production (number of products)?
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In today's session of ERP, we discussed the goals of production planning.
A case study regarding the causes of disruption in SAP and the changing trends in Toyota Motors was also discussed.
The case identified three trends for Toyota Motors:
  • lean manufacturing,
  • Vertical integration (means the extent to which a company produces the components and assemblies used in the products it manufactures).
  • supply base rationalization.
These trends—lean manufacturing, reduced vertical integration, and supply base rationalization—have been implemented by manufacturers in a number of industries over the past 30 years and have resulted in higher efficiencies and reduced cost.
More over, we practiced some exercises of SAP implementation in Financial Statements and Cost Centres.
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In my experience the biggest challenges in SAP are related to poor management.
For instance if several hundred components are quarantined for a quality inspection. A portion of them may be ok and a portion of them may need to be scrapped. However we have to rely on human interaction to correctly identify the ok parts and scrap the bad parts. What we found is the scrap parts remained in quarantine. This ment because the system didn’t know if the parts where ok or not it never re-ordered them. Then we ended up with a situation where manufacturing said that there wasn’t enough parts, could quality release the quarantined parts, the answer was no because they are scrap. Therefore production would have to stop until the supplier could send in more parts.
The root cause being a lack of process and lack of training. The system is very good but relies on human element. If the information you put in is rubbish, you get rubbish out.
Hope that helps
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Oil Production has been a project of mine. Are you aware of Operations Research efforts in this arena? If interested in such, see and articles.
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What are some topics related to sustainable manufacturing that are still in need of development and future research?
My masters thesis must incorporate some type of system modeling geared toward reducing energy Costs, however I am having diFficulty finding a topic that is unique and under developed. my Literature review consists of topics such as: production planning, predictive maintenance, buffer optimization, reduction of peak demand, systems which utilize renewable energy and or chp systems, agent based modeling, machine learning, etc.
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Sustainable development can be achieved by various methods. Which method will be selected is determined by many factors of the environment, the environment of specific economic processes as well as the specifics of economic enterprises and the national economy. However, in the absence of a key development factor, a key raw material such as water can be a significant cost barrier for the implementation of the process of achieving sustainable development. Sustainable development can not be excluded in the context of continuous irrigation of agriculture, but it will generate high costs. In such a situation, profitable ventures should be developed in the domestic economy, which will allow to finance the costs of the said irrigation. It can not be ruled out that irrigated poor soil with proper fertilization and use will produce high yields, high production of agricultural produce will be generated and after a few or more years, it will be possible to create more complex flora ecosystems, including forests next to arable fields, and the way can be improved. Then, sustainable development will be analyzed, implemented and improved in terms of the national economy.
I invite you to the discussion
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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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My supervisor is too busy and I've did my best working on it, I just need someone to tell me if there's something wrong with the outline or if there's some really eye catching mistake ( not read it in detail). Thank you very much! 
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Sarah,
A couple inputs.
 The problem you were trying to solve and path to conclusions are not clear in the paper. I get your formula's etc. But why the are important to the work being accomplished is not clear.
  Did you identify opportunities within the constraints defined by your supervisor? If so what were the opportunities identified and how did validate your results to enable you to propose a change? Did the operation improve its throughput? Did it lower its inventory? etc. Was there a strategic contribution?
 Your modeling was interesting but what did that modeling do for you in addressing your problem statement. You indicated that you were to elaborate a production plan. Was there no plan and if so our were they operationally functioning? What results did your elaboration yield?
It sounds like a unique learning period for you. But I would look at your flow and start with the problem and how you gradually built to a solution using the tools that and operational research training to get to a optimized plan and why it was good for this business.
  Many times internships are opportunity for some business to achieve some extra resources during a times of busyness. But you have a goal personally to obtain some experience and apply your education to solve a problem. Because the result gives you a completed thesis. You may want to organize this in that sort of flow. Good luck and interesting work.
Don Myers
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it is as following :
A capacitated lot sizing problem with :
-multi item
-multi machine
-minimum inventory constraints
-changeover times between items
-It's a big bucket problem, the horizon is 18 months and periods are months
Can you please give me insights about how to solve it ( without any solver only oriented programming ), knowing that it is NP hard and I have very large instances with 18 periods, up to 5000 items and 20 machines.
Thank you very much
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@Ali Vatankhah barenji Thank you so much dear,  never heared of it, joined ResearhGate not so much ago and here I am learning so much! Thank you loads again for sharing your knowledge with me, I will check it out and get back to you if I need more information. 
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I want to model a production line.
The objective function is to minimize production time in the production line which will be feasible via workers collaboration.
Each production line have several workstations which are placed in sequence and one feature of this production line is that the product should be finished in each workstation to be transferable to the next workstation. It means the amount of work in the first workstation should be 100% and then production in the second workstation could be started otherwise the production rate in the second workstation would be zero. The same holds true for the relation between production in station two and three. The production in the second station should be finished afterward the production in the third station could be started. Otherwise the production rate of the third workstation is equal to zero.
I want to know if there is any specific trick in linear programming to solve this issue. Also, is there somebody who knows how to model this issue in AIMMS?
If you know any similar example please send it to me.
Thank you for your comments,
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What you can do - or not do - depends largely on several set-ups, like those of the machines, how resources are handled around the machines,vthe requirements on quality, time constraints, and so on. I was the main supervisor of Karin Thörnblad, who worked with GKN Aerospace on high-tolerance products, using flexible workshop models. Look up her publications for some samples of real cases.
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I would like to know if anyone is working in this topic. It would be interesting if we can work together in this research line that has a wide camp of action.
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this topic is one of my research interests and directions. i can forward you to the following related publications in connection with this topic:
Bayar, N., Darmoul, S., Gabouj, S.-H., Pierreval, H., (2015). Using Immune Designed Ontologies to Monitor Disruptions in Manufacturing Systems. Computers in Industry, Vol. 81, September 2015, Pages 67–81, DOI: 10.1016/j.compind.2015.09.004
Darmoul, S., Pierreval, H., Gabouj, S.–H. (2013). Handling Disruptions in Manufacturing Systems: an Immune Perspective. Engineering Applications of Artificial Intelligence, vol. 26, issue 1, pp. 110–121, http://dx.doi.org/10.1016/j.engappai.2012.09.021.
Darmoul, S., Pierreval, H., Gabouj, S.-H., (2011). Using ontologies to capture and structure knowledge about disruptions in manufacturing systems: An immune driven approach. In Proceedings of the 16th IEEE International Conference on Emerging Technologies and Factory Automation, ETFA 2011, Toulouse, France, September 5th – 9th, 2011. http://dx.doi.org/10.1109/ETFA.2011.6059033
Mabkhot, M. M., Al-Samhan, A. M., Darmoul, S., (2016). An information model to support reconfiguration of manufacturing systems. Accepted in the fourth IFAC International Conference on Intelligent Control and Automation Sciences, ICONS2016, June 01-03, 2016, Reims, France. http://dx.doi.org/10.1016/j.ifacol.2016.07.086
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While comparing the old tax structure application on all construction activities (Material, plant & machinery, logistics) with new one. Inclusion of facts and figures is preferred.
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Dear Urvi
If you have a project to be constructed most probably you have done your planning and scheduling using the CPM method and software such as Primavera (ORACLE) or Project (Microsoft).
In there, you have to detail for each activity in the network all the costs (labor, materials, transportation, taxes to be paid, etc)
As you know, from the CPM network you can get the Gantt schedule and from it the projected investments during the life cycle of the project up to its conclusion, and materialized by the budget curve.
Any new GST must be incorporated in the planning, after deleting the old one, and then the new budget curve will show you new values. For each month and comparing the old budget curve with the new one you can deduct the impact of the new policies.
It could be that because the new budget there could be financial problems. In that case you should modify the last budget curve by working with the floats in the CPM in order to delay execution of non-critical tasks without altering the completion date.
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I need reference to some literature where a supply chain partner agrees to pay at a higher rate to keep the transaction feasible for the other (weaker?) partner. I cant seem to find anything. If anybody can suggest some direction, it will be very helpful. 
Thanks and regards.
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The entities created correctly at 6:30-700am, but it skipped the 11:30am-12pm one (second peak) and entities were created near end of day instead (around 10pm).
I also make sure I edited the schedule using spreadsheet so the zeros are there from 12pm to 12am. 
Thank you! 
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Check simulation time in RUN setup
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What are the disadvantages of Variety Reduction in purchasing and supplies?
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1-Requirements once considered part of the reason for the project now cut. A potentially great idea could be skipped over as being "out of scope".
2- Leave project capable of include out of scope projects later. Document reasons for not including items, and a time frame for looking into it again later.
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Of course, I mean the formulation like this:
When teaching OR, I use this kind of the ILP problem as a simple example where LP must be "supplemented" with integer variables. However, my students expect practical applications to the models I teach them, not only their formal mathematical correctness. And what can I say to them? Well, you must know all the cutting patterns before you optimize. It's easy to find those patterns at least in the 1D-CSP case. Even if we are restricted to 1D-CSP only, it is still an important application. But there may be hundreds or thousands of cutting patterns and, what follows, integer variables even in a possibly small and simply problem. So, the whole thing often becomes useless.
My question is really the following:
Is there any case in which the considered ILP form of CSP (restrict it to 1D-CSP) is better in some sense (time of optimization, but also e.g. availability of free software) to compare with other 1D-CSP models (those with "guaranteed" optimal solutions, not like First Fit Decreasing for example)? Or, more practically, does anybody know any real-world case of a company in which the ILP form of CSP is actually used in production planning?
I don't want to teach something which is nothing but a practically useless mathematical concept, that's all.
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This "academic" problem is perfect for educational purposes, as you can use it as an example of the column generation principle (extending Dantzig-Wolfe to integer programs). It's an age-old story - Dirickx-Jennergren's book from - I think - 1979 is full of things like this. Very good!
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I want to know if someone has studied the effect of the spiral of economics of apparel dress shirt making in terms of speed of processing , different process for the making, if the size of the batch change is a limiting issue, if the discrete process approach of manufacturing lay out to a straight line manufacturing concept affects , or any other variables are considerable to as to describe or forecast an economic model upon the cost performance per unit produced in a developing country?.- Please any comments I would appreciate.
thanks
Alex Banegas 
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Maybe these articles can provide more details:
Saludos :-)
Management of international technology transfer: A case study in the Brazilian textile industry
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I am associated with a research work related to product-line strategies of fast-moving consumer goods in Nepal and South Asia. I will appreciate your support in advising good works in this topic.
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Dear Arhan,
These papers may be helpful:
1- Bilgen, B., & Günther, H. O. (2010). Integrated production and distribution planning in the fast moving consumer goods industry: a block planning application. Or Spectrum, 32(4), 927-955.
2- Francis, M. (2006). Stage model research in the UK fast moving consumer goods industry. International Journal of Logistics: Research and Applications, 9(4), 351-368.
3- Grant, D. B., & Banomyong, R. (2010). Design of closed-loop supply chain and product recovery management for fast-moving consumer goods: the case of a single-use camera. Asia Pacific Journal of Marketing and Logistics, 22(2), 232-246.
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Information sharing and exchange between OEMs and suppliers is a new approach to enable responsiveness.
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Besides smooth flow of information, the process includes smooth flow of materials from suppliers, smooth production and smooth delivery to end customers.
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Can the way physical objects are moved, stored, realized, supplied and used throughout the world be economically, environmentally and socially improved in order to guarantee sustainability via a wide-spread adoption of iso-modular boxes?
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Hi Edoardo Marcucci!
Its a pleasure.
Cheers
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“Productivity is, above all, an attitude of the mind. It seeks continually improve what already exists. It is based on the believe that one can do things better than yesterday and tomorrow better than today. Also, it requires a lot of efforts to adapt economical activities to changing conditions applying news theories and methods. It’s a firmly believe on the progress of the human been”.
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Hello Ronald,
Productivity is nothing but just a performance measurement which can be seen both in company and national scales. Productivity which is calculated as a ratio of Output(s)/ Input(s) shows how the company utilized its resources in order to produce products or offer services. In national scale, productivity is known as one of the most important reasons of economic growth.
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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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I am analyzing one operation of distribution with about 600 SKUs where the picking occurs using the method man to product. Some items with 2 or minus touches by week are located in subdivided pallets with up to 4 products in floor and on the first pair of beams of the pallet racks and concentrated in a few aisles.
But the efficiency of the cube usage is low and the travel distance is still high.
My idea is to use the classical solution of shelving, but maybe the dynamic pick face technique would be feasible.
What other solutions do you use or have you used in the past with good results and low implementation costs?
Thank you in advance!
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From a similar project.  Improve the ergonomics.
Ensure that the lighting is at the required level of lumens.  Warehouses are often dimly lit. This improved our case greatly.  Besides bright, improve the 'look' of the surroundings.  Make pick lists in the same order as the storage of SKUs; thus, the flow of people, carts and SKUs is the same.  Use bar code readers to deliver, display and confirm pick lists.  (More expensive)
Hand picking is best with products on the sides, easily reached, and the container for orders down the middle.  Use a system to check off items as collected.  You can use load cells to check the weight of the order. You can to this a couple of times along the route, if needed. 
Use an audit approach to check a percentage of the orders and improve the process to eliminate systemic problems.
Organize SKUs such that the most frequently picked items are at the beginning of the route or at the beginning of rows and near the collection point.
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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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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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needed some papers on parallel computing in remote sensing ,production planning(assembly operations),geo intelligence(defence),agriculture,robotics.
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BIM increases the efficiency of collaboration through all phases of a construction project, but there are a few constraints to both BIM and lean project delivery in certain scenarios depending on various factors that influence the construction of a project. How can BIM be utilized to overcome these constraints and contribute to collaboration and procurement of Lean Project Delivery?
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Stefan Boeykens, i totally agree with the benefits of BIM in lean project delivery, where the effort is directed into the source that generates information which provides results through all stages of the project.
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Thanks.
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some research by prominent researchers : Gunasekaran,Stevenson,QTu
Basic concepts on Modularity  by Karl Urlich..
Happy Researching..
Regards,
Dr.Kottala SriYogi
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I would like to know if there are statistics or researchers showing how frequently multinational companies relocate their production facilities around the globe. I am not interested in new investments or divestments, but only relocation.
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Multinational companies may adapt production more flexibly than outright relocation (meaning shutting down a production unit or terminating a supplier contract). First, sometimes changes in the disaggregration of the value system (say, a value chain) may lead to relocating some, but not all production activities. Second, to the extent that their production network has some flexibility (excess capacity) external changes (e.g. foreign exchange) may induce them to shift some, but not necessarily all, production across their network of production facilities. 
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I am working on a problem where I need to model cost of production as depending upon several factors. Can anybody please suggest some article, book or other monologue where this has been done.
Thanks in advance.
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I am strongly agree with the answers/discussions of Prof.Nita H. Shah & Prof. Jens Schütze.
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I was just wondering what substantive research is presently being carried out in this area. What are the gaps that still need to be filled?
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No one seems to answer this question.  Does that mean that the question is not clear/not formulated well?
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We know that the problem with release dates is NP-hard.
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I don't think I understand your question.  It is never optimal for the machine to be idle if all release times are 0.  Proof: if the machine is idle for epsilon time units, change the schedule by doing everything after the idle time epsilon earlier.  The weighted completion time will decrease by n times epsilon where n = # of jobs completed after the idle time.   A similar argument called "swapping" proves that preemption is never optimal.  Suppose job a finishes before job b finishes, but job b runs for a while before job a finishes.  Make a and b trade epsilon>0 time, where b gives a time before a finishes and a gives b time after b has run for a while.  Then b's finish time stays the same but a's finish time is strictly better.  Swapping is also how you prove that if job a has larger weight/runtime than b, then a should be scheduled before b.  If not there will exist two consecutive jobs that violate this ordering rule.  Swap them.  It's a simple computation to see that the sum of weighted completion times strictly decreases.
If this does not answer your question, please clarify what you mean about idle times.
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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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I need websites for supply chain concepts with reference to inventories
or some mail id od experts in this area of optimization
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Int'l Journal of Production Economics
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As far as I know, a single-level CLSP is an NP-hard problem. Multi-level CLSPs are more complex than single-level ones.
What is the main strategy in solving a Multi-level CLSP?
What's the difference between the strategies for Single-level ones and those for Multi-level ones?
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When you say 'level', do you mean 'item' or do you refer to the levels of a BOM structure? Because a problem can be single-level but multi-item (and still hard to solve).
If you mean with 'solving' finding a 'good solution', obviously there are many heuristic methods that work very well in practice. If you are aiming to find the 'optimal' solution, then it's of course not to be expected with a realistic size problem -- there are some inequalities (such as the classical (l,S) inequalities) and reformulations (such as the facility location reformulation) that might well in practice to close the gap (I'd advice the first in practice as the problems can get messy with reformulations due to increase in dimension). Also other exact methods such as Benders decomposition and Lagrangean relaxation can be very handy.