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In light of the current international concerns with security and terrorism, interest is increasing on the topic of using robot swarms to locate the source of chemical hazards. The purpose of this paper is to place this task, called chemical plume tracing (CPT), in the context of fluid dynamics.

This paper provides a foundation for CPT based on the physics of fluid dynamics. The theoretical approach is founded upon source localization using the divergence theorem of vector calculus, and the fundamental underlying notion of the divergence of the chemical mass flux. A CPT algorithm called fluxotaxis is presented that follows the gradient of this mass flux to locate a chemical source emitter.

Theoretical results are presented confirming that fluxotaxis will guide a robot swarm toward chemical sources, and away from misleading chemical sinks. Complementary empirical results demonstrate that in simulation, a swarm of fluxotaxis‐guided mobile robots rapidly converges on a source emitter despite obstacles, realistic vehicle constraints, and flow regimes ranging from laminar to turbulent. Fluxotaxis outperforms the two leading competitors, and the theoretical results are confirmed experimentally. Furthermore, initial experiments on real robots show promise for CPT in relatively uncontrolled indoor environments.

A physics‐based approach is shown to be a viable alternative to existing mainly biomimetic approaches to CPT. It has the advantage of being analyzable using standard physics analysis methods.

The fluxotaxis algorithm for CPT is shown to be “correct” in the sense that it is guaranteed to point toward a true source emitter and not be fooled by fluid sinks. It is experimentally (in simulation), and in one case also theoretically, shown to be superior to its leading competitors at finding a source emitter in a wide variety of challenging realistic environments.

This paper tests the fit of three models of integrative and distributive bargaining using eight hostage negotiation transcripts. Putnam (1990) argues that integrative and distributive bargaining processes are best understood through the interdependence model that emphasizes the dynamic nature in which bargainers make transitions between integrative and distributive positions. The separate and the stage models predict more stable patterns of distributive and integrative behavior. To determine the goodness of fit for these three models, this paper compares integrative and distributive strategy use among actual and simulated hostage negotiations. These hostage negotiations, obtained from the FBI and a Midwest state police organization, were transcribed and coded using a scheme designed to tap cooperative and competitive strategy use of both hostage takers and police negotiators. The data reveal that the interdependence model best fits the simulated cases. This fit is evidenced by the major shifts between integrative and distributive orientations displayed by hostage takers and police negotiators. The separate models and the stage appear to fit several features of the authentic hostage negotiation cases. The study concludes that the extent to which each model emerges depends largely on which contextual parameters dominate the interaction.

Aims to develop an efficient and robust system for real‐time personal identification by automatic face recognition.

A wavelet‐based image hierarchy and a guided coarse‐to‐fine search scheme are introduced to improve the computation efficiency in the face detection task. In addition, a Gabor‐based low feature dimensional pattern is proposed to deal with the face recognition problem.

The proposal of a wavelet‐based image hierarchy and a guided coarse‐to‐fine search scheme is effective to improve the computation efficiency in the face detection task. The introduction of a low feature dimensional pattern is powerful to cope with the transformed appearance‐based face recognition problem. In addition, the use of aggregated Gabor filter responses to represent face images provides a better solution to face feature extraction.

Provides guidance in the design of automatic face recognition system for real‐time personal identification.

Biometrics recognition has been emerging as a new and effective identification technology that attains certain level of maturity. Among many body characteristics that have been used, face is one of the most commonly used characteristics and has drawn considerably large attentions. An automated system to confirm an individual's identity employing features of face is very attractive in many specialized fields.

Introduces a wavelet‐based image hierarchy and a guided coarse‐to‐fine search scheme to improve the computation efficiency in the face detection task. Introduces a Gabor‐based low feature dimensional pattern to deal with the face recognition problem.

In order to solve the problem that the performance of the existing local feature descriptors in uncontrolled environment is greatly affected by illumination, background, occlusion and other factors, we propose a novel face recognition algorithm in uncontrolled environment which combines the block central symmetry local binary pattern (CS-LBP) and deep residual network (DRN) model.

The algorithm first extracts the block CSP-LBP features of the face image, then incorporates the extracted features into the DRN model, and gives the face recognition results by using a well-trained DRN model. The features obtained by the proposed algorithm have the characteristics of both local texture features and deep features that robust to illumination.

Compared with the direct usage of the original image, the usage of local texture features of the image as the input of DRN model significantly improves the computation efficiency. Experimental results on the face datasets of FERET, YALE-B and CMU-PIE have shown that the recognition rate of the proposed algorithm is significantly higher than that of other compared algorithms.

The proposed algorithm fundamentally solves the problem of face identity recognition in uncontrolled environment, and it is particularly robust to the change of illumination, which proves its superiority.

The presence of heavy metals in milk causes many acute and chronic physiological dysfunctions in human organs. The present study aims to investigate the heavy metals in cow's and buffalo's milk of two major cities, Karachi and Gujranwala, Pakistan to estimate metal intake by humans from this source.

In total, 48 milk samples from 2 cities were drawn from animals' udder to avoid contamination. Each sample was digested with nitric acid at 105 ^oC (degree Celsius) on a pre-heated electric hot plate to investigate the metals by atomic absorption spectroscopy (flame type). Air-acetylene technique analyzed chromium, cadmium and lead, and the hydride method analyzed arsenic in the milk samples.

The results revealed the highest mean lead concentration (19.65 ± 43.86 ppb) in the milk samples, followed by chromium (2.10 ± 2.33 ppb) and arsenic (0.48 ± 0.73 ppb). Cadmium was not detected in any sample, assuming cadmium's occurrence was below the detection level. The concentrations of all the metals in the samples of the two cities do not differ statistically. Lead concentrations in the buffalo's milk were higher than in cow's milk (p < 0.05). However, the concentrations of arsenic and chromium between buffalo's and cow's milk do not differ statistically. The present study reveals a lower level of metals in the milk than those conducted elsewhere. The mean concentrations of all the metals met the World Health Organization's (WHO) safety guidelines (1993).

Although cadmium causes toxicity in the human body, cadmium could not be measured because cadmium's concentration was below the detection level, which is 1 ppb.

This study will help reduce the toxic metals in our environment, and the sources of heavy metals, particularly from the industrial sector could be identified. The feed and water consumed by the milking animals could be carefully used for feeding them.

This study will help reduce the diseases and malfunction of human organs and organ systems since these heavy metals cause toxicity and carcinogenicity in humans. Arsenic and chromium cause cancer while lead causes encephalopathy (a brain disease).

The study reports heavy metal concentrations in the two attributes of four independent variables of raw milk samples that were scarcely reported from Pakistan.

The purpose of this paper is to discuss that in an uncontrolled business environment public companies' resources may be abused to fund other group companies by their management.

The paper has been designed on fraud theory. The theory has been developed on interviews with key management personnel, financial analysis, audit tests and gathering the facts on each step.

The paper concludes that in an uncontrolled financial market, owners, executives and statutory company auditors acting in harmony may break the financial rules, statutory obligations and convert a healthy public company into bankruptcy by means of milking its resources to other group companies on unfeasible projects or on individual pleasures.

Auditors both internal and external should pay attention to intragroup transactions. Companies, partially or wholly owned by the public might be under the influence of owner/executives. Here, it is not only the government interests as tax or social insurance, but also the shareholders' interests are at stake.

Resources are scarce, especially in developing countries. The public's savings must be sourced to feasible projects in trustworthy hands, otherwise public's trust is shaken which will deter potential shareholders to invest in capital markets, and consequently these negative repercussions will affect the whole community.

The case that the paper covers reflects the author's own audit experiences as an ex‐auditor. The names of the companies have been changed but not the essence of events. It is believed that the paper will shed light onto the path of the reader who might be an external or an internal or a statutory auditor or a manager of a company who might be involved in similar situations.

A significant sector of the international tourism industry focusses on the natural and cultural attributes of target destinations and sites. The more natural and unusual the attraction the greater the value to the industry and hence the greater the promotion of the venue. However, this pattern of exploitation could prove to be a short cut to actually degrading the object of attraction and hence its pulling power.

The purpose of this work is to assess the influence of ambient noise on the performance of wireless sensor networks (WSNs) empirically and, based on these findings, develop a mathematical tool to assist technicians to determine the maximum inter-node separation before deploying a new WSN.

A WSN test platform is set up in an electromagnetically shielded environment (RF chamber) to accurately control and quantify the ambient noise level. The test platform is subsequently placed in an operational laboratory to record network performance in typical unshielded spaces. Results from the RF chamber and the real-life environments are analysed.

A minimum signal-to-noise ratio (SNR) at which the network still functions was found to be of the order 30 dB. In the real-life scenarios (machines, telecommunications and computer laboratories), the measured SNR exceeded this minimum value by more than 20 dB. This is due to the low ambient industrial noise levels observed in the 2.4 GHz ISM band for typical environments found at academic institutions. It, therefore, suggests that WSNs are less prone to industrial interferences than anticipated.

A predictive mathematical tool is developed that can be used by technicians to determine the maximum inter-node separation before the WSN is deployed. The tool yields reliable results and promises to save installation time.

Bates' information search tactics have been influential in the practice and teaching of online searching since they were published in 1979. This paper is about using information search tactics to search the internet, and aims to present a set of tactics useful in the practice and teaching of internet searching.

Tactics used on the internet were gathered from the literature, web sites, and the author's experience of internet searching. These were compared with the information search tactics, and refined into a set of internet search tactics.

The article presents 34 internet search tactics: 18 of the original Bates tactics, interpreted in the context of the internet, and 16 new tactics. While many of the information search tactics are relevant, effective internet searching requires recognition of the role of relevancy ranking and full text searching in search engines. The uncontrolled nature of the internet means that evaluation of information resources is an integral part of internet searching, so a group of evaluation tactics have been proposed.

The tactics provide a framework for teaching effective internet searching.

Bates' information search tactics do not appear to have been applied as a whole to searching the internet. The proposed tactics will be useful for librarians and researchers who need to carry out effective searching on the internet, and for information literacy education. Research into information seeking and search interfaces will be informed by the tactics.

This paper aims to explore the strategy development process followed by firms during the current economic and financial crisis through the relationship between changes in performance measures and strategic success factors.

A survey to executives of global firms asking the importance of widely accepted performance indicators and strategic success factors has been performed obtaining 53 usable surveys. Test has been performed to identify respondent bias. Empirical results from the survey are presented and t‐tests have been performed to validate the statistical significance of the change in importance of performance indicators and strategic success factors.

The findings suggest that firms followed a reactive strategic development process since they adjusted their strategic direction to the short‐term problems in their performance affected by the economic crisis. While firms may focus their attention to similar set of performance measures during the crisis, their strategic behavior to face the crisis differs.

While the sample is small (53 respondents), the authors believe that the quality of the respondents, senior managers and directors with responsibility for strategic development processes, compensates for the small number of responses.

Rehearsing strategies can be a powerful tool to avoid reactive strategic behavior either anticipating environmental constraints through scenario planning or testing the robustness of strategic initiatives using diverse tools like strategic modeling.

The paper offers an empirical validation of strategic development processes under uncertainty considering the linkage between changes in organizational performance, performance indicators and strategic success factors.