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BACKGROUND: There is little published research about managers’ views about implementing and embedding workplace health promotion interventions. OBJECTIVE: To shed light on research-to-practice challenges in implementing workplace health promotion interventions in the Australian road transport industry. METHODS: In this Participatory Action Research project, managers from small-to-midsized companies in the Australian road transport industry were asked their views about enablers and barriers to implementing nutrition and physical activity interventions in their workplace. RESULTS: Managers identified practical assistance with resources, ideas, and staffing as being key enablers to implementation. Barriers included time restraints, worker age and lack of interest, and workplace issues relating to costs and resources. CONCLUSION: Manager perspectives add new insights about successful implementation of workplace health promotion. A Participatory Action Research approach allows managers to develop their own ideas for adapting interventions to suit their workplace. These findings add to a small body of knowledge about managers’ views regarding implementing workplace health promotion in small-to-midsized road transport companies – a relatively unexplored group. Managers highlight the importance of time constraints and worker availability when designing interventions for the road transport industry. Managers require a good understanding of the workplaces’ socio-cultural context for successful health promotion and health behaviour change.

Purpose Workplaces are challenging environments which place workers at the risk of obesity. This is particularly true for Australian road transport industry workplaces. The Analysis Grid for Environments Linked to Obesity (ANGELO) framework is a public health tool which can be used to conceptualise obesogenic environments. It suggests that workplaces have a variety of roles (in the physical, economic, political and sociocultural domains) in responding to obesity in transport industry workplaces. The purpose of this paper is to present the findings which explore this idea. Design/methodology/approach The project used a mixed-methods approach located within a participatory action research framework, to engage workplace managers and truck drivers in the implementation and evaluation of workplace health promotion strategies. The project involved six transport industry workplaces in Queensland, Australia. Findings This study found that transport industry workplaces perceive themselves to have an important role in addressing the physical, economic, political and sociocultural aspects of obesity, as per the ANGELO framework. However, transport industry employees – specifically, truck drivers – do not perceive workplaces to have a major role in health; rather, they consider health to be an area of personal responsibility. Practical implications Balancing the competing perceptions of truck drivers and workplace managers about the workplace’s role in health promotion is an important consideration for future health promotion activities in this hard-to-reach, at-risk population. Originality/value The use of the ANGELO framework allows the conceptualisation of obesity in a novel workplace context.

Background Road trauma had been identified as the leading cause of work-related death in Australia. Research in general driving behaviours has shown that sensation seekers with high levels of thrill and adventure seeking traits are more likely to drive in a risky manner. However, thrill and adventure seeking has not been explicitly examined as a predictor of risky driving behaviour in work-related settings. Methodology Using a large sample of fleet drivers ( N = 892) from three Australian organisations, the current study examined the role of thrill and adventure seeking in predicting risky work-related driving behaviours and involvement in crash and traffic offence. Hardcopies and online version of the questionnaire were sent to the worksite measuring participants' demographic information, work driving exposure, thrill and adventure seeking trait, work-related risky driving behaviours, and self-reported crash and traffic offences in the past 12 months. Results The results indicated that thrill and adventure seeking was a significant predictor of risky work-related driving behaviours. However, thrill and adventure seeking did not significantly predict self-reported crashes and traffic offences. Conclusion The current study implies that dispositional characteristics, such as thrill and adventure seeking, should be considered when implementing interventions in fleet safety.

Research on concepts associated with risk management and theoretical frameworks associated with safety culture and safety citizenship behavior are reviewed, along with their practical application within the work driving safety setting. A model incorporating safety citizenship behavior as a complementary paradigm to safety culture is proposed. It is suggested that this model provides a theoretical framework to inform future research directions aimed at improving safety within the work driving setting.

BACKGROUND Australia's mineral, resource and infrastructure sectors continues to expand as operations in rural and remote locations increasingly rely on fly-in, fly-out or drive-in, drive-out workforces in order to become economically competitive. The issues in effectively managing these workforces are becoming more apparent with reported high amounts of turnover and concerns for safety and performance. The issues presented include a range of physical, mental, psychosocial, safety and community challenges. OBJECTIVES This review aims to consolidate a range of research conducted to communicate potential challenges for industry in relation to a wide variety of issues when engaging and using FIFO/DIDO workforces which includes compressed working schedule design (work schedules), working hours, fatigue, safety performance, employee wellbeing, turnover, psychosocial relationships and community concerns. METHODS A comprehensive literature review was performed using EBSCOhost, PubMed and google scholar, with a focus on FIFO or DIDO workforces engaged within the resources sector. Search terms were kept broad in order to capture all national and international research conducted and included: "fly-in, fly-out" "FIFO" "DIDO" "drive-in, drive-out" "mining". There was no date restriction included in the search. RESULTS Many of the studies were focused on sleep quality, fatigue and the influence of lowered safety performance while at work, presenting an increased risk for health and safety. These issues may be exacerbated for the FIFO workforce when linked to additional research surrounding the extended periods of absence from families influencing workers personal relationships, psychological wellbeing, job satisfaction and the reported high amounts of turnover within the industry. Taken together, this presents a unique implication for the management and continued use of FIFO workforces when considering balancing safety and performance with economic viability of production and operations. CONCLUSIONS The issues of long working hours, fatigue, turnover and job satisfaction are not new to the management of workers. However, FIFO workforces appear to be at an increased risk physically and mentally due to a culmination of other influences, such as extended and frequent periods of absence from friends and families which contribute to feelings of isolation and lowered psychological wellbeing. FIFO workers and their families, engage in a unique lifestyle, rarely are other workers subjected to long hours and compressed work weeks while separated or isolated from their families for extended periods of time. Recently, FIFO interest has shifted to understanding the influences on employee engagement, satisfaction, retention and safety. Considering the management of FIFO workforces from a holistic perspective incorporating all of the issues impacting on these workers may assist to ensure the challenges associated with FIFO employment are understood, addressed and communicated to workers and their families is crucial for safety and health.

Reversing vehicle incidents is a significant but often overlooked issues in organisations. Utilising three Australian organisations, this study aimed to evaluate the efficacy of reversing aids and a behaviour-change program in reducing reversing-related crashes in fleet settings. Reversing-related incidents increased from Time 1 to Time 2 in the organisation that did not implement a specific strategy to reduce their reversing-related crashes and in the organisation that implemented the reversing aids intervention. However, the increase was only statistically significant in the organisation that utilised the reversing aids technology. In this organisation, the odds of its drivers getting involved in a reversing incident has almost doubled from Time 1 and Time 2. In contrast, the frequency of reversing incidents in the organisation implementing the behaviour-change program has significantly decreased, with less than 50 % chance of its drivers being involved in a reversing incident from Time 1 to Time 2. The implications associated with these results will be discussed.

One of the expected effects of climate change is a change in the magnitudes of extreme temperatures. This effect is likely to be pronounced on the Canadian Prairies, which experience a continental climate. This study investigates the extreme minimum temperatures of the winter season at rural or small urban prairie locations, having long periods of record. For each winter month, daily minima are analysed for the number of occurrences of temperatures colder than two standard deviations from the mean minimum for the month. A Mann‐Kendall nonparametric test for the trend is then applied to the counts obtained for the period of record in order to test the significance of the results. Following this, a spatial analysis of each month's trend is carried out using inverse distance weighting. During January and February it was found that there was a significant trend towards fewer occurrences of very cold minimum daily temperature during the period 1914–94. This is especially noticeable in western portions...

Climate Change is anticipatedto result in alterations in cyclone activity over the northern hemisphere. Cyclones in their passage across the open prairie of western Canada spawn one of the more extreme weather events that occur in that part of the country; blizzards. Numerous studies of individual blizzards are available. The objective of this study of blizzards is to identify trends in their seasonal occurrence, in seasonal blizzard weather element extremes, and discuss the results in the context of climate change. Criteria used in western Canada to define a blizzard event during the period of study were applied to the archive of hourly weather data for locations within the Prairie Ecozone. Blizzard events were extracted for the period 1953–1997 and analyzed for trends in seasonal occurrence. Results of this analysis are presented which illustrate a significant downward trend for weather observing locations in the more westerly part of the prairies. This trend is consistent with results found by others that indicate a decrease in cyclone frequency over western Canada. No significant trend was found in the more central and eastern locations. No significant trend was evident in seasonal extremes of blizzard weather elements at most locations.

A concept of tunable electric-LC (ELC) resonators is presented in this work. The voltage-controlled tunability is achieved by using liquid crystal in a micro-fluidic channel running through the central capacitive gaps. To attain the largest tunability, the structure is optimized through a parametric analysis using full-wave electromagnetic simulations. The simulation results predict a 6% continuous frequency tuning for this ELC resonator around the frequency of 4.5 GHz. The achieved results demonstrate the possibility of using these ELC resonators in an array to form a tunable frequency selective surfaces (FSS). The principle can be scaled for operation at higher microwave frequencies, where the dissipation of liquid crystal is low.

Fast probability integration (FPI) algorthms are adapted, extended and used to perform nuclear engineering uncertainty analyses. Methods are presented to improve the efficiency and precision of FPI for frequently encountered input distributions, to permit quick estimates of extreme model output quantiles and to provide appropriate sensitivity and uncertainty importance measures. Advantages and disadvantages of FPI as a stand-alone method are explored in two demonstration applications. FPI is first applied to estimate extreme (0.95, 0.99, 0.999 and 0.9999) quantiles of the frequency of a dominant station blackout accident. Sensitivity measures are quantified to indicate how the relative importance of each model input changes at progressively more extreme output quantiles. FPI is next applied to analyze uncertainties in fire damage times predicted by compbrn iiie . Alternative FPI-based uncertainty importance measures are compared and shown to consistently rank the input contributions to the output uncertainty. FPI results are compared with results obtained from Monte Carlo sampling to demonstrate the computational advantage that clearly favors FPI, especially at the more extreme output quantiles. In a third application, Latin hypercube sampling (LHS) is combined with FPI to determine extreme quantiles of peak cladding temperature during the blowdown phase of a large-break loss of coolant accident as modeled by trac-pfi/mod2 . The 0.95 quantile peak cladding temperature is reproducibly determined to within 2 K in one LHS-FPI iteration, which is based on only 21 trac-pfi/mod2 runs. To demonstrate convergence for a more extreme case, LHS-FPI is also applied to estimate the 0.999 quantile peak cladding temperature. In each LHS-FPI iteration a final code run is performed to assure that the code-calculated peak cladding temperature agrees with that predicted by LHS-FPI at the most probable point. Importance measures are quantified at this point to identify dominant input-output relationships. Compared with past code scaling, applicability and uncertainty (CSAU) analyses, LHS-FPI offers a significant reduction in the number of best-estimate code runs required while providing additional checks and insights.

The characterization of a tunable band-pass filter based on stepped-impedance resonator (SIR) is presented in this work. The designed filter uses a half-wavelength resonator patch above a multi-layer substrate, with liquid crystal as its central layer, making it continuously tunable at frequencies around S-band. Two liquid crystal samples are considered for three different approaches: lumped-element circuit simulation, full-wave electromagnetic simulations and prototype measurements. The results demonstrate the possibility of using a simple lumped-element circuit simulation for rapid calculation of the performances of liquid crystal devices at microwave frequencies.

Liquid crystals have potential applications in the design of tunable microwave devices. Polyimide films are commonly incorporated in designs to achieve reproducible molecule alignment in the unbiased state. In this investigation two separate resonator elements are designed and investigated: One is fabricated with polyimide layers and one without. Experimental results obtained with a patch resonator illustrate that about half of the maximum tuning range is achieved without polyimide layers. Since substrates able to sustain a temperature range of 180–300 °C are required for the polyimide film curing process, avoiding polyimide enables using even lower heat resistant substrates for various tunable microwave applications and can lead to faster fabrication processes.

Vitamin B₁₂ is found almost exclusively in animal-based foods and is therefore a nutrient of potential concern for those following a vegetarian or vegan diet. Vegans, and anyone who significantly limits intake of animal-based foods, require vitamin B₁₂-fortified foods or supplements. Vitamin B₁₂ deficiency has several stages and may be present even if a person does not have anaemia. Anyone following a vegan or vegetarian diet should have their vitamin B₁₂ status regularly assessed to identify a potential problem. A useful process for assessing vitamin B₁₂ status in clinical practice is the combination of taking a diet history, testing serum vitamin B₁₂ level and testing homocysteine, holotranscobalamin II or methylmalonic acid serum levels. Pregnant and lactating vegan or vegetarian women should ensure an adequate intake of vitamin B₁₂ to provide for their developing baby. In people who can absorb vitamin B₁₂, small amounts (in line with the recommended dietary intake) and frequent (daily) doses appear to be more effective than infrequent large doses, including intramuscular injections. Fortification of a wider range of foods products with vitamin B₁₂, particularly foods commonly consumed by vegetarians, is likely to be beneficial, and the feasibility of this should be explored by relevant food authorities.

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Two 6 GHz microstrip patch antennas made from conducting polymers with relatively low DC conductivity such as PEDOT (10000 S/m) and PPy (2000 S/m) are presented. The performance of these patch antennas is compared with a similar copper patch antenna. The results indicate that it is possible to obtain reasonable performance albeit with modest radiation efficiencies. The PEDOT antenna achieved a maximum gain of 2.2 dB, while the PPy antenna reached a gain of 3.8 dB, as against 6.0 dB for a corresponding Cu patch antenna The results confirm the potential of polymer materials for microwave antennas and suggest that CPs may be of use in other passive microwave circuit applications.

Getsinger's Longitudinal Section Electric model describing the propagation characteristics of a single layer microstrip line is modified to cater for ‘n’ layers. An accurate closed-form expression for two and three layered structures is presented and validated against full-wave numerical results. The computed effective permittivity for a randomly selected two and three layer dielectric microstrip line is presented. In the selected examples, for the modified Getsinger model, the dispersion of effective permittivity is within 2–3% relative error for two-layer and within 6–7% relative error for three-layer dielectric microstrip lines for frequency up to 50 GHz. In contrast, for the same structures, the relative errors in previously reported works are above 10% for two layers and above 15% for three-layer dielectric substrates.

Limitations to current long range weather radars include reduced coverage of the lower atmosphere, coarse cross range resolution and coarse temporal resolution due to the mechanical scanning. A proposed network of low cost, short range digital radars for monitoring hydrometeor phenomena is described and its potential benefit in providing lower atmospheric coverage is discussed. The benefits of replacing the scanning antenna at each node of the network with a phased array are also discussed.

th Generation Flash Ladar system which produces real-time, 3-dimensional (3D) video in all lighting conditions has been demonstrated to be a significant enabler to enhance the mission capabilities of Unmanned Aerial Vehicles (UAVs). These new capabilities include enhanced Intelligence, Reconnaissance and Surveillance (ISR), Automated Target Recognition (ATR), improved situational awareness, GPS denied (terrain relative) navigation, 3D surface mapping, surface change detection (detection of buried improvised explosive devices), camouflage penetration, autonomous aerial refueling and autonomous landing. Ball Aerospace 5 th Generation Flash Ladar system has benefited from over 6 years of development, is compact, modular, and has been demonstrated to be easily integrated and flight-tested on both fixed-wing and rotorcraft with different optical configurations. This paper presents the results of airborne test activities and sample imagery of our 5 th Generation system and discusses options for repackaging and integrating the system into UAV platforms. I. Introduction all Aerospace has significant experience in providing ladar systems for remote sensing applications. NASA’s CALIPSO lidar was built by Ball and has celebrated a number of operational milestones, including an extension of the 3-year initial mission lifetime and over 1 billion laser firings and associated atmospheric measurements. Further, Ball Aerospace is developing the flash ladar navigation system for NASA’s space exploration missions. These programs leverage Ball’s extensive understanding of ladar systems, real time image processing algorithms, guidance, navigation and control algorithms, laser system engineering, and the phenomenology being exploited. 1

A Microstrip Patch Antenna (MPA) has been fabricated using a Conducting Polymer (CP), Polypyrrole (PPy) as radiating patch on a transparent 3mm thick Plexiglas™ substrate. The bulk DC conductivity of the PPy patch is 2000 S/m and its thickness 120 µm. The MPA was designed for operating at 2 GHz. A similar antenna with Copper (Cu) patch on Plexiglas™ was also fabricated for validating the simulation of PPy antenna and comparing its performance. The results show that the PPy antenna reaches a gain of 5.01 dB at 2.18 GHz as against 6.26 dB at 2.2 GHz for a corresponding Cu patch antenna. The conduction efficiency of Cu-patch antenna is around 80% while that of PPy-patch antenna is around 60%. The results suggest that it might be possible to use CPs in other passive microwave circuit applications.

Radio frequency identification (RFID) systems are part of modern life. They are revolutionizing the way companies run their businesses, cars pay tolls and employees access an office in a building. RFID devices are also making their way quickly into other industries including health care where they are used in remote of monitoring equipment, as tiny chips that identify items in inventory, or are even embedded in surgical sponges for tracking during an operation. Although in many regions RFID regulations are very strict and operators must adhere to the standard, the unpredictable environmental effects on radio propagation can change the way that these devices operate. This paper offers a review of important EMC information relevant to RFID system deployment. It also examines the sources of error in simulations reported in some other publications.

Crash data involving taxis indicates that such drivers are over represented in crashes and are one to two times more likely to be involved in a fatality crash. This study reports on the pre intervention survey to provide a baseline measure of the self-reported attitudes and corresponding driving behaviours of a sample of taxi drivers. Results indicate that some taxi drivers willingly admit to engaging in unsafe driving practices. In addition, preliminary results of a post intervention survey revealed that taxi drivers’ safety perceptions, attitude and behaviours improved after completing a Driving Diary intervention.

Sparse array imaging systems (developed in ultra sound medical imaging) using a co array can be deployed on small UAVs to eliminate grating lobes on a wideband radar. This allows the use of thin film antennas under the aircraft wing using a split transmit and receive aperture. Simulations show side lobes equivalent to an array of 2 times the linear dimension. Apodization reduces sidelobes to -100 dB, but a secondary lobe is apparent at 0.5-0.8 π. Z transform apodization will reduce the secondary lobe. It can be eliminated entirely using sub kernel convolution with the Z transform. (5 pages)

Radar requirements differ from commercial Radio-Over-Fibre (ROF) systems. High signal to noise ratio (SNR) and spurious free dynamic range (SFDR) in a photonic beam forming architecture are paramount. The architecture described in this paper uses phase modulation to overcome previous limitations. It provides high SNR, low-distortion mixing, enabling optical systems to be used in radar, beamforming and similar applications. (5 pages)

Contemporary policy debates on the macroeconomics of aid often concentrate on short-run Dutch disease effects, ignoring the possible supply side impact of aid— financed public expenditure. We develop a simple model of aid and public expenditure in which public infrastructure capital generates an inter-temporal productivity spillover for both tradable and non-tradable sectors, where these productivity effects may display sector-specific biases. The model also allows for non-homothetic demands. We then use an extended version of this model, calibrated to contemporary conditions in Uganda, to simulate the effect of a step increase in net aid flows. Our simulations show that beyond the short-run, where Dutch disease effects are present, the relationship between enhanced aid flows, real exchange rates and welfare is less straightforward than simple models of aid suggest. We show that public infrastructure which generates a productivity bias in favour of non-tradable production delivers the largest aggregate return to aid, with the real exchange rate appreciation reduced or reversed and enhanced export performance, but it does so at the cost of a deterioration in the income distribution. Income gains accrue predominantly to urban skilled and unskilled households, leaving the rural poor relatively worse off. Under plausible parameterizations of the model the rural poor may also be worse off in absolute terms.

We introduce the Network Photonics' Crosswave as the first commercially-available, MEMS-based wavelength selective switch. The CrossWave combines the functionality of signal demultiplexing, switching and re-multiplexing in a single all-optical operation using a dispersive element and 1-D MEMS. 1-D MEMS, where micronurrors are configured in a single array with a single mirror per wavelength, are fabricated in a standard surface micromachining process. In this paper we present three generations of micromirror designs. With proper design optimization and process improvements we have demonstrated exceptional mirror flatness (

Probably the most enduring result in the theory of optimum income taxation is that, for a sufficiently thin upper tail to the skill distribution, the marginal tax rate should fall rather than rise with income. This paper shows that this result is highly sensitive to a very strong informational assumption, namely that earnings exactly reflect a worker's contribution to output. While the formal structure of the optimum problem is altered only slightly when earnings are allowed to be less than perfectly correlated with productivity, the shape of the optimum schedule is very sensitive to this relaxation. For high but imperfect correlation, optimum schedules look rather like those traditionally chosen by governments, with the marginal rate rising over high incomes and possibly U-shaped over the whole distribution.

It has been argued that the institutions of the CFA Franc zone may have reduced inflation but that they also induced misalignment of the real exchange rate and that this is the explanation for their dismal revenue performance. This paper uses a panel of 22 countries in sub-Saharan Africa to estimate revenue performance over the period from 1980 to 1996. It finds that the poor cumulative relative revenue performance of the franc zone countries is mainly attributable to differences in environmental and structural factors, and that different responses to changes in the equilibrium real exchange rate, but that the misalignment of the real exchange rate also played a part.

Thy monolithic integration of MicroElectroMechanical Systems (MEMS) with the driving, controlling, and signal processing electronics promises to improve the performance of micromechanical devices as well as lower their manufacturing, packaging, and instrumentation costs. Key to this integration is the proper interleaving, combining, and customizing of the manufacturing processes to produce functional integrated micromechanical devices with electronics. We have developed a MEMS-first monolithic integrated process that first seals the micromechanical devices in a planarized trench and then builds the electronics in a conventional CMOS process. To date, most of the research published on this technology has focused on the performance characteristics of the mechanical portion of the devices, with little information on the attributes of the accompanying electronics. This work attempts to reduce this information void by presenting the results of SPICE Level 3 and BSIM3v3.1 model parameters extracted for the CMOS portion of the MEMS-first process. Transistor-level simulations of MOSFET current, capacitance, output resistance, and transconductance versus voltage using the extracted model parameters closely match the measured data. Moreover, in model validation efforts, circuit-level simulation values for the average gate propagation delay in a 101-stage ring oscillator are within 13 - 18% of the measured data. These results establish the following: (1) the MEMS-first approach produces functional CMOS devices integrated on a single chip with MEMS devices and (2) the devices manufactured in the approach have excellent transistor characteristics. Thus, the MEMS-first approach renders a solid technology foundation for customers designing in the technology.

When a country emerges from a lengthy war, it is inevitable that the transition to a peacetime economy should have profound budgetary consequences. A number of African countries have embarked on this transition in recent years, and it is to be hoped that others will soon follow suit. In these circumstances, it is natural to enquire whether the fiscal challenges and opportunities accompanying the transition have common features, and whether the experience of countries which began the process relatively early may be useful in the formulation of policy in the others. This paper considers this question, using the experiences of Uganda and Ethiopia to illustrate Section 2 identifies a number of potentially systematic features, and later sections look at these in more detail. Section 3 discusses the revenue characteristics of the transition and Section 4 considers expenditure patterns. Section 5 looks briefly at the impetus to decentralise, and Section 6 concludes.

While generalisation is perilous, there are many, especially small, developing countries for which sales taxes and turnover taxes are fairly negligible as revenue sources and for which import duties and export taxes, particularly the former, are leading revenue sources. For evidence from the early I980S see Tanzi (I987) and Greenaway and Milner (I990). This observation is unsurprising when account is taken of the administrative constraints to which many developing countries are subject. Sales taxes can be difficult to collect, not to mention a complex tax like VAT. Income tax is largely infeasible and often has to take a simple form, such as a payroll tax confined in practice to public and large company employment. Some taxes which would be assumed to be eminently feasible in industrial economies may not generate as much revenue as might be supposed in a developing country. For instance, tax disks which the law may require heavy goods vehicles to carry may generate a flow of bribes to police and other officials if these are wise enough to set the bribe at a modest level, making it cheaper to pay bribes than to buy a disk. A cynic might say that the bribes are an unofficial source of revenue if their existence enables the state to get away with paying its officials absurdly low salaries. One would have to hope, if that argument is accepted, that the officials do something socially useful apart from stopping heavy goods vehicles. Such considerations make it interesting to consider the design of public finance for a country severely constrained in its choice of what Musgrave called 'tax handles', that is, types of tax instrument which it may practically employ: The existing literature, for which Newbery and Stern (I987) provides an excellent review, throws some light on this issue, but the problem is seldom treated explicitly. An exception would be Dreze and Stern (I985), whose highly abstract and general treatment of cost-benefit analysis theory can be seen to incorporate principles of public finance which fully cover the restricted policy choices which I have in mind. Because the approach of these authors is so general, however, it is not easy to extract conclusions for tax design in specific cases. This is no criticism of the paper, of course, as the argument is addressed to cost-benefit analysis. Generally speaking, theory has developed in the direction of sophisticated and complex tax systems. The next section discusses why this is so from the point of view of theory. Yet ideal tax systems would be difficult to implement in many developing countries. As I shall treat tariffs as a highly feasible revenue