## Linear Programming using Whats Best

A convenient way of creating models to solve linear programming problems is to use the What's Best add-in for Microsoft Excel. A demo version of What's Best is available from Lindo Systems. After installation, the What's Best toolbar becomes available in Excel (Fig. 1.1). Decision, uncontrolled, or endogenous variables are called adjustable cells in What's Best . The value of the objective function is called the best cell. A linear programming model can be constructed by transcribing the...

## Open Designs structuring of a design problem

The structuring commonly used in design problems for the purpose of mathematical optimisation originates from the domain of operations research (OR). In that domain, reference is made to 'design' problems and 'decision(-making)' problems. By doing so, OR experts do not recognise the obvious relationship between a design problem and a decision problem. After all, one cannot make a decision about something without having 'conceived' (designed) it first. Design problems and decision problems are...

## Deterministic network planning CPM

Modelling a construction planning using LP software is in essence no more than translating the (graphical) relations between the different activities into mathematical equations. The relation between two activities in a construction planning can easily be translated into a mathematical formula. We will restrain ourselves to Finish-to-Start relations with a relation-duration of zero. In the critical path method the activity-duration is considered invariable. Consider the part of an AON*...

## Open Design Cases and Exercises

1 The realisation area (shaded) 212 1.1 What's Best toolbar 218 1.2 The standard LP form represented in Excel with What's Best 219 1.4 Screenshot solved model (project developer's problem) 222 1.5 Screenshot solved model (municipality's problem) 224 1.6 Screenshot solved model (facility manager's problem) 226 1.8 Screenshot solved model (maximising the number of affordable houses) 230 1.9 Screenshot solved model (maximising the project developer's fee) 230 2.1 Monte Carlo simulation for a real...

## Monte Carlo simulation

To determine how much the investor can invest in a lift, to get at least the same return at the same risk level as without a lift, we have to search for input variables which generate the same return-risk profile for both cases. This can be done, in a trial and error manner, with the following assumptions (Table 10.1) Investment for a multiple family unit without lift - Pessimistic optimistic estimates 10 from best guess. Rest value 80 of initial investment. Exploitation results from regression...

## An office renovation project

An example of the Open Design methodology applied in an office renovation project is the upgrading of the former KLM head office on the Plesmanweg in the Hague (Binnekamp, 1995). In the year 1979, the building had been in use for ten years by its second owner, the Ministry of Infrastructure. The building badly needed a thorough overhaul including maintenance of the outside of the building, improving the ventilation, modernising the interior and making the office designs of the various wings...

## Linear single variable regression analysis

Consider a firm of architects that has data on 30 types of houses from a project. The database has data on the cost price and on both the gross and usable floor-space per house. Table 4.1 shows the content of the database. For instance, type 3A has a cost price of 98,352 and has a gross floorspace of 163 m2 and a usable floorspace of 122.2 m2. The firm wishes to develop a formula to predict the cost price of a (similar) house based on either the gross or usable floorspace. Figure 4.1 shows a...

## Monte Carlo simulation of a portfolio of real estate investments

Real estate investors are primarily interested in the risk profile (probability distribution of expected return) of their portfolio of projects. What we need, therefore, is a method to conduct a Monte Carlo simulation for a portfolio of projects with different starting dates, different lifetimes and different risk profiles. Any project, j, of a portfolio of N projects has a past (indicated by subscript P) and a future (indicated by subscript F). The NPV is the sum of the NPV over the past and...

## Key Issues Matrix

In the management of the project the concept of a Key Issues Matrix played an important role in focussing attention on the right issues and addressing them with appropriate management tools. On the horizontal axis are placed the management tools addressing the key issues, such as communication, continuity of staff, delegation procedures and lessons from other projects. On the vertical axis are placed the key issues put forward by the project managers. Then the question was asked what can each...

## European airport in the North Sea a rational and feasible option for the European main airports

Environmentalists are, in general, not interested in local solutions which only move pollution problems elsewhere. They wish to resolve pollution issues globally. In regard to air transport, they favour substitution of air transport by rail transport. For the long distances of intercontinental connections, air transport is the only possibility when travel time is of any importance. Intercontinental trains simply do not exist. As a result, environmentalists tend to accept intercontinental...

## Appendix A Grannys puzzle

On the request of the first author (who was a member of the Committee) Hennes A.J. De Ridder (1994) wrote a fairy tale to make clear what his Ph.D. thesis was all about. The story illustrates so well that the separation of Design and Construct (D& C) is artificial, that we feel that it deserves to be added as an unabridged appendix to this book. A Client's grandmother, who is fond of puzzles but who is too old for puzzling now, is celebrating her birthday. Client wants to surprise...

## Behavioural theory of Argyris and Schn a summary

Behaviour is governed by theories of action. A theory of action is defined in terms of a particular situation, S, a particular consequence, intended in that situation, C, and an action strategy, A, for obtaining consequence C in situation S. The general form of a theory of action is similar to a computer program. If you intend to produce consequence C in situation S, then do A. A theory of action, whether it applies to organisations or individuals, may take two different forms. By espoused...

## The use of multiple variable linear regression analysis in architectural design

In general, cost prices depend on much more than one variable. To derive rules of the thumb for cost prices calculations we have to conduct multiple variable (linear) regression analysis of databases on past construction projects. Most cost price calculation procedures, for instance SVINSK which is in use in our faculty, are based on regression analysis. The so-called REN-norms, giving cost price calculation rules, for office buildings, constitute another example. The term 'norms' is...

## Analyse database using correlation analysis

The properties 'Number of addresses per square kilometre' and 'Number of houses per hectare' are very similar, which means that, possibly, only one should be used in the regression analysis. For this purpose correlation analysis is carried out prior to the regression analysis. To determine whether a coefficient is meaningful to include in the regression, the following relationship holds (for derivation, see standard text books on statistics) Z coefficient depending on the chosen confidence...

## Risk assessment in network planning through Monte Carlo simulation

As a solution for this problem, Lanza (2003) proposes a Monte Carlo approach. In essence, this involves the following steps 1. Establish most optimistic most likely most pessimistic estimates for the duration of all project activities 2. Calculate the Critical Path using the most-likely-estimates. So far the procedure is the same as in traditional PERT planning 3. Establish one or more other paths through the network that may actually become critical paths as a result of high variability in the...

## Risk diversification example portfolio of projects

As an investor you have a portfolio with real estate objects with estimated characteristics as shown in Table 2.3. You first add the portfolio characteristics to the MCS software or alternatively open the sample project O e_mcs-3 . Figure 2.5 Portfolio characteristics Figure 2.5 Portfolio characteristics You can check the portfolio's characteristics by clicking either the 'Input' or 'PortFolio Input' tab. This will show output as shown in Figure 2.5. You can then click the 'Perform Portfolio...

## Best practices of project management

In Tables 2.1, 2.2, 2.3 we have summarised, in ten aspects, the best practices for project management and their implications as can be found in the literature on the subject. We call them PI practices, for simple projects, which we distinguish from PII practices, being more appropriate for managing complex projects. These PII practices, will be presented in Chapter 3. They have been summarised in the same ten aspects. Of course, our summary of PI management practices is by no means exhaustive,...

## Open Design a Collaborative Approach to Architecture

1 The potential of mathematical modelling for architecture and urban planning has increased dramatically in the nineties 8 1.1 Sjoelbak Dutch shuffleboard 10 1.2 Expert design sjoelbak 10 1.3 Multi-stakeholder sjoelbak design 11 1.4 Mathematical modelling in Open Design 16 2.1 In Open Design, the product champion needs several benefactors 23 3.1 Graphical representation of professor's time allocation problem 28 3.2 Professor's time allocation problem 28 3.3 Manufacturing allocation problem 31...