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Lewbel and Pendakur (2009) developed the idea of implicit Marshallian demands. Implicit Marshallian demand systems allow the incorporation of both unobserved preference heterogeneity and complex Engel curves into consumer demand analysis, circumventing the standard problems associated with combining rationality with either unobserved heterogeneity or high rank in demand (or both). They also developed the exact affine Stone index (EASI) implicit Marshallian demand system wherein much of the demand system is linearised and thus relatively easy to implement and estimate. This chapter offers a less technical introduction to implicit Marshallian demands in general and to the EASI demand system in particular. I show how to implement the EASI demand system, paying special attention to tricks that allow the investigator to further simplify the problem without sacrificing too much in terms of model flexibility. STATA code to implement the simplified models is included throughout the text and in an appendix.

Recent methods of data organisation have sought to preserve the original sequence of keys in the address space yet this often also results in the wastage of valuable storage space as a consequence of the simultaneous preservation of gaps in the sequence. The method of key space compression using forbidden zones seeks to minimize such wastage by removing those gaps in the sequence corresponding with keys which the designer knows beforehand cannot occur.

IN this paper an attempt is made to describe rapid, precise, efficient methods for solving aeroplane geometry problems by analytic geometry.

Consumers tend to have problems interpreting cost information, such as the annual percentage rate (APR), pertaining to loans. Students were used to test people's spontaneous estimates of loan cost when only the payment pattern was known, but not the APR or the total finance charge (FC). Experiments show that some absolute measures such as the FC seem to be used rather than relative measures when ranking loans. This leads to a bias against loans of longer duration. This can be avoided by using a heuristic, an approximate APR, by a simple development of the FC. The last section examines the problem of estimating the duration change when the interest rate is altered. Experiments show that the duration is generally underestimated when only the payment pattern and the interest rate are known. If the FC per month is known the situation improves somewhat, but still the effects on the duration of changing interest rates are underestimated.

The dynamic nature and complexity of construction projects make it challenging to ensure that the engineer-to-order (ETO) materials supplied onsite match changing needs. The quick and efficient communication of required changes in material fabrication, delivery and use, due to changes in the design and construction schedules, is needed to address the challenges. This study aims to provide a novel integrated management framework with its embedded informatics to help major stakeholders efficiently absorb agility during communication to deal with required changes and improve workflows.

An integrated management framework is developed that integrates the milestones in look-ahead plans and structured iterative processes for major supply chain stakeholders to quickly disseminate information emanating from changes in design, schedules, production and transportation. A prototype system is devised including the informatics to support the framework, which consists of BIM-RFID functional modules and a central database and uses a client-server architecture. The usefulness of the prototype is illustrated using a construction of part of a fictive but realistic high-rise building.

The integrated management framework with the informatics provides major stakeholders with the ability to coordinate their activities efficiently and stimulate their agility (measured by process time) in planning and controlling material information. Although only a fictive example was used, it is shown that the use of the system is likely to result in a substantial reduction in the time required to deal with required changes when delivering ETO materials onsite (by 18% in the example).

The functionalities of the prototype system can be easily scaled up to coordinate changes in the design and scheduling of other types of materials. More functional developments are needed to show the extent of the possible improvement for entire construction projects. Future work should focus on investigating the possible improvements for other types and sizes of construction projects, and eventually in real-world construction projects.

By fitting the look-ahead plans into structured iterative processes through digital data sharing, stakeholders increased their capability to quickly capture required change information and resolve associated problems. This is particularly useful for the management of ETO supply chain processes, where prefabricated elements such as ductwork, plumbing, and mechanical systems typically have to be modified because of last-minute design and schedule changes.

Unlike traditional information technology (IT) based supply chain management practices, this research is characterized by a process-centered management framework that provides explicit decision points over iterative planning processes for major stakeholders to manage material information. The iterations through digital data sharing allow stakeholders to quickly respond to last-minute changes on site, which fundamentally achieves workflow agility in the construction supply chain context.

Geometrical transformations are used to specify the spatial relationship between two cubes. The analysis can be applied to the description of the error in a robot placement task in three‐dimensional space, or to the relative location between two arbitrary rigid bodies in such a space.

Classic models for distribution systems design have usually considered only basic aspects such as power capacity limits, power demand requirements and the minimization of a single‐objective function that represents the total system expansion cost. However, multiobjective design models include aspects such as reliability evaluations, the optimal voltage profile in the network, social amenity values and geographical conditions of the study area, as well as the basic design aspects. In this paper, a multiobjective model is presented for optimal design of distribution systems by finding the best reliability of the network and the least expensive system expansion simultaneously. A multiobjective method used in applications of the model to practical distribution systems design problems is outlined. The computer results indicate that multiobjective models achieve satisfactory solutions, which consider multiple objectives simultaneously. These solutions, preferred by the planner, are advantageous compared with the classic design solutions.

The purpose of this paper is to analyze the sensitivity of the motion error parameters in microassembly process, thereby improving the assembly accuracy. The motion errors of the precision motion stages directly affect the final assembly quality after the machine visual alignment.

This paper presents the error parameters of the in-house microassembly system with coaxial alignment function, builds the error transfer model by the multi-body system theory, analyzes the error sensitivity on the sensitive direction using the Sobol method, which was based on variance, and then gets the ones which made a great degree of influence. Before the sensitivity analyzing, parts of the error sources have been measured to obtain their distribution ranges.

The results of the sensitivity analysis by the Sobol method, which was based on variance, are coincident with the theoretical analysis. Besides, the results provide a reference for the error compensation in control process, for the selection of the precision motion stages and for the installation index of the motion stages of the assembly system with coaxial alignment.

This kind of error sensitivity analysis method is of great significance for improving the assembly accuracy after visual system positioning, and increasing efficiency from the initial motion stage selection to final error compensation for designers. It is suitable for general precision motion systems be of multi-degree of freedom, for the method of modeling, measuring and analyzing used in this paper are all universal and applicative.

This paper aims to examine information and communications technology (ICT) adoption among small hotel businesses in South Africa, Botswana and Zimbabwe.

This qualitative research is based on seven case studies that fall within the South African and European Union small and medium enterprises (SMEs) definitions. The case studies are constructed on the basis of 60 semi‐structured interviews and supporting secondary data. The authors adopt the Gibbs et al. model which identifies and brings together ICT adoption factors that include government role, environmental attributes, owner/manager attributes, organisational attributes and social networks. Archer's epistemological bootstrapping technique is applied for analysing the data. In addition, Zappala and Gray's stage model is used to gauge the level of ICT uptake reached by each case study. In this way, the authors incorporate an important additional element for examining ICT adoption.

Apart from providing rich insights into the ICT adoption process, the results highlight the individual distinctive behavioural characteristics as well as the stage of ICT adoption reached by each case study. The paper finds that case studies that operated in a stable business environment; with organisational readiness; financial and owner manager support seemed readily engaged in ICT adoption. Social networks played a crucial role, especially among those small businesses with resource constraints.

The findings from seven individual cases in the three South African Development Community (SADC) countries have limited cross‐case and cross‐national comparisons owing to the distinctive organisational characteristics of the SMEs. Furthermore, the selection of case studies from a single sector of small hotel businesses results in data which only reflect the experiences of SMEs in typical urban locations of Johannesburg, Gaborone and Harare. The implications of these limitations mean that further data are needed from other small firm sectors and more SADC countries in order to gain a better understanding of ICT adoption among SMEs in the region.

The findings contribute to the literature on ICT adoption among SMEs in South Africa, Botswana and Zimbabwe. The results bring new insights from small hotel businesses and help to explain ICT adoption, which is relatively under‐researched in these SADC countries.

Multiobjective planning models for electric power distribution system planning can include multiple aspects such as community amenity values, geographical conditions of the study area, reliability evaluations (mainly in terms of service continuity), or the optimal voltage profile in the network, as well as the basic planning aspects: power demand requirements, power capacity limits and the minimization of the total system expansion costs. On the other hand, classical single objective planning models have usually considered only the basic aspects. This paper describes a multiobjective model to find the optimal voltage profile and to look for the least cost system expansion simultaneously. Furthermore, two multiobjective techniques for the application of the model to distribution system expansion problems are outlined. The computer results have shown that multiobjective models are able to find solutions which include multiple planning objectives simultaneously, and that these solutions are advantageous compared with the ones from classical single objective models.