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Ready-mix concrete delivery problem (RMCDP), a specific version of the vehicle routing problem (VRP), is a relevant supply-chain engineering task for construction management with various formulations and solving methods. This problem can range from a simple scenario involving one source, one material and one destination to a more challenging and complex case involving multiple sources, multiple materials and multiple destinations. This paper presents an Internet of Things (IoT)-supported active building information modeling (BIM) system for optimized multi-project ready-mix concrete (RMC) delivery.

The presented system is BIM-based, IoT supported, dynamic and automatic input/output exchange to provide an optimal delivery program for multi-project ready-mix-concrete problem. The input parameters are extracted as real-time map-supported IoT data and transferred to the system via an application programming interface (API) into a mixed-integer linear programming (MILP) optimization model developed to perform the optimization. The obtained optimization results are further integrated into BIM by conventional project management tools. To demonstrate the features of the suggested system, an RMCDP example was applied to solve that included four building sites, seven eligible concrete plants and three necessary RMC mixtures.

The system provides the optimum delivery schedule for multiple RMCs to multiple construction sites, as well as the optimum RMC quantities to be delivered, the quantities from each concrete plant that must be supplied, the best delivery routes, the optimum execution times for each construction site, and the total minimal costs, while also assuring the dynamic transfer of the optimized results back into the portfolio of multiple BIM projects. The system can generate as many solutions as needed by updating the real-time input parameters in terms of change of the routes, unit prices and availability of concrete plants.

The suggested system allows dynamic adjustments during the optimization process, andis adaptable to changes in input data also considering the real-time input data. The system is based on spreadsheets, which are widely used and common tool that most stakeholders already utilize daily, while also providing the possibility to apply a more specialized tool. Based on this, the RMCDP can be solved using both conventional and advanced optimization software, enabling the system to handle even large-scale tasks as necessary.

Based on the context of the Internet of Things (IoT), the territorial public emergency supplies will be networked, platform-based management, unified emergency dispatch. The problem of supplies dispatching in the “last kilometer” of emergency is solved, and the supplies needed in the disaster area are promptly delivered to the hands of the victims so that they can quickly be rescued after the disaster and to save valuable time for rapid rescue, which can greatly decrease casualties and property losses. This paper aims to discuss these issues.

By analyzing the shortage of existing emergency supplies dispatching research and taking all factors such as disaster area demand, social reserve, road conditions, mode of transport, loading limit, disaster area satisfaction rate and road capacity into consideration under the background of IoT, a variety of the territorial emergency supplies dispatching model with more rescue points, more affected areas are constructed. The objective function of the model is to aim in finding the shortest rescue time, giving the solution algorithm, and finally simulating the simulation case.

Based on the context of the IoT, the territorial public emergency supplies will be networked, platform-based management, unified emergency dispatch. Considering factors such as road conditions, modes of transport and road capacity, the authors construct a number of emergency rescue plans, multiple disaster scenarios and various emergency supplies dispatching models. The authors simulate the situation through simulation cases with the shortest time being the ultimate goal. The problem of supplies dispatching in the “last kilometer” of emergency is solved, and the supplies needed in the disaster area are promptly delivered to the hands of the victims so that they can quickly be rescued after the disaster and to save valuable time for rapid rescue, which can greatly decrease casualties and property losses.

This paper provides little research on the dispatch of emergency supplies. The problems of direct dispatch from the rescue point to the affected area and dispatch of supplies without relying on the arrival of emergency supplies at the rear are addressed. Therefore, this study does not focus on the arrival of emergency supplies at the rear but on direct dispatching issues during territorial public emergency supplies from the rescue point to the disaster point.

The purpose of this paper is to create a model of FM and location variables in the dimensions of location and recessions.

The approach is based on statistical analysis and quantitative methodology.

Significant differences and correlations argue for four settings with different features, first, in the dimension of single or multiple site locations, and second, the dimension in low and high growth of GDP, here termed “recession” and “boom”, respectively.

This paper is a relevant study for growth firms in multiple facilities management perspectives.

A better knowledge and decision basis related to relocation and behaviour of FM during fluctuations of GDP is expected.

The paper presents a survey of FM‐related data that covers an entire nation and all major business sectors, collected concerning two successive periods, and analysed.

A threatened sense of safety in public spaces is a problem for liveable communities. For better public policies, this study investigates multi-dimensional and multi-scalar aspects of gendered perceived safety and strategies by women and men in daily public spaces.

A face-to-face survey with 40 men and 50 women in a public space (Izmir, Turkey) is deployed. Descriptive statistics and regression analysis compare participants' perceptions of and strategies for safety across the city, neighbourhood and the study site.

Their experienced-based familiarities in public places increase women's perceived safety. As safety strategies, different place-based and gendered-preconditions appear for women and men going “outside” especially “alone” (i.e. unaccompanied). Reaffirming female vulnerability in public places, gendered preconditions include individuals' attributes. Of place-based preconditions, crowd and police are significant mechanisms for safety but emphasized differently by women and men. Housewives' female companionship in the study site develops a class- and gender-based claim for a safe place away from their underserved neighbourhood.

Gendered- and place preconditions for women's safety can inform design policies about surveillance and permeability of public spaces. Lack of data about class-based differences about perceived safety is a limitation.

Among a few, it takes perceived safety as performative acts with learned strategies across (rather than momentary perceptions in) socio-spatial spaces and provides a research framework that considers such acts with individual and spatial dimensions across multiple socio-spatial scales.

In the hotel industry today, web site marketing and third party distribution metrics are of critical importance in understanding the effectiveness of hotel revenue management objectives. The purpose of this paper is to propose a new model which tests hotel web‐effectiveness using the following variables: reach, content, consistency and price parity (RCO2P).

For the current RCO2P study, the hotel sample was broken down into two segment groupings of five hotels: luxury; and upper‐upscale. The ten full‐service hotels were monitored over a 90‐day period using room rate quotations and ordinal values across 14 dimensions based on three pre‐selected arrival dates.

Results of the RCO2P study indicated preferential display sequencing emerged as a significant factor in the reach category among all hotel properties reviewed. Only six of ten properties were measured as having achieved optimal web‐effectiveness, while poor price‐parity competency reflected the most situation‐critical performance among sampled hotel properties.

International comparative research methodologies were examined and determined to be effective models of certain hotel web‐effectiveness dimensions; however, a comprehensive hotel web‐effectiveness measurement model is still lacking which can better inform hotel industry executives. Therefore, future research should incorporate a best practice research approach combining the current RCO2P study elements with other web‐effectiveness measurement criteria based on the collective best practices identified among the research studies reviewed.

While there is increasing interest in implementing drug checking within overdose prevention, we must also consider how to scale-up these responses so that they have significant reach and impact for people navigating the unpredictable and increasingly complex drug supplies linked to overdose. The purpose of this paper is to present a distributed model of community drug checking that addresses multiple barriers to increasing the reach of drug checking as a response to the illicit drug overdose crisis.

A detailed description of the key components of a distributed model of community drug checking is provided. This includes an integrated software platform that links a multi-instrument, multi-site service design with online service options, a foundational database that provides storage and reporting functions and a community of practice to facilitate engagement and capacity building.

The distributed model diminishes the need for technicians at multiple sites while still providing point-of-care results with local harm reduction engagement and access to confirmatory testing online and in localized reporting. It also reduces the need for training in the technical components of drug checking (e.g. interpreting spectra) for harm reduction workers. Moreover, its real-time reporting capability keeps communities informed about the crisis. Sites are additionally supported by a community of practice.

This paper presents innovations in drug checking technologies and service design that attempt to overcome current financial and technical barriers towards scaling-up services to a more equitable and impactful level and effectively linking multiple urban and rural communities to report concentration levels for substances most linked to overdose.

The purpose of this paper is, first, to assess the potential of the visual to enact multiplicity and reflexivity in organizational research, and second, to develop a performative approach to the visual, which offers aesthetic strategies for creating future research accounts in organization and management studies.

The paper reviews existing visual research in organization and management studies and presents an in‐depth analysis of two early, almost classical, and yet very different endeavors to create visual accounts based on ethnography: the multi‐media enactments by Bruno Latour, Emilie Hermant, Susanna Shannon, and Patricia Reed, and the filmic and written work by Trinh T. Minh‐ha and her collaborators.

The authors’ analysis of how the visual is performed in both cases identifies a repertoire of three distinct and paradoxical aesthetic strategies: de/synchronizing, de/centralizing, and dis/covering.

The authors analyze two rarely acknowledged but ground‐breaking research presentations, identify aesthetic strategies to perform multiplicity and reflexivity in research accounts, and question the ways that research accounts are written and published in organization and management studies by acknowledging the consequences of a performative approach to the visual.

For parts of the time on a typical construction site concrete pour, the site placing crew is idle waiting for the arrival of the next truckmixer delivery, whereas for other periods, truckmixers are idle on site waiting to be unloaded. Ideally, the work of the crew should be continuous, with successive truckmixers arriving on site just as the preceding truckmixer has been emptied, to provide perfect matching between site and concrete plant resources. However, in reality, sample benchmark data, representing 118 concrete pours of 69 m³ average volume, illustrate that significant wastage occurs of both crew and truckmixer time. The purpose of this paper is to present and explain the characteristics of the wastage pattern observed and provide further understanding of the effects of the factors affecting the productivity of this everyday routine site concreting system.

Analytical algebraic models have been developed applicable to both serial and circulating truckmixer dispatch policies. The models connect crew idle time, truckmixer waiting time, truckmixer round trip time, truckmixer unloading time and truckmixer numbers. The truckmixer dispatch interval is another parameter included in the serial dispatch model. The models illustrate that perfect resource matching cannot be expected in general, such is the sensitivity of the system to the values applying to those parameters. The models are directly derived from theoretical truckmixer and crew placing time-based flow charts, which graphically depict crew and truckmixer idle times as affected by truckmixer emptying times and other relevant parameters.

The models successfully represent the magnitudes of the resource wastage seen in real life but fail to mirror the wastage distribution of crew and truckmixer time for the 118 pour benchmark. When augmented to include the simulation of stochastic activity durations, however, the models produce pour combinations of crew and truckmixer wastage that do mirror those of the benchmark.

The basic contribution of the paper consists of the proposed analytical models themselves, and their augmented versions, which describe the site and truckmixer resource wastage characteristics actually observed in practice. A further contribution is the step this makes towards understanding why such an everyday construction process is so apparently wasteful of resources.