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An autonomous mobile robot requires efficient perception of the environment to perform various tasks in a challenging environment. The precise sensory information from the range sensors is required to accomplish prerequisites, such as SLAM, path planning and localization. But the accuracy and precision of the sensors become unreliable in harsh environmental conditions because of the effect of rain, dust, humidity, fog and smoke. The purpose of this paper is to generate robust mapping of the environment in harsh environmental conditions.

This paper presents a novel technique, averaging data with short range selection (ADWSRS), to reduce the effect of harsh environmental (rain, wind, humidity, etc.) conditions on sensory information (range) to generate reliable grid mapping. The sensory information on laser and sonar sensors in terms of probability values (occupied/unoccupied cell) in generating grid maps are fused after passing through two newly designed pre-processing filters: laser averaging filter and short range selection filter. This proposed approach relies on various aspects such as averaging laser data analogous to current pose of the sensor, selection of short range with respect to threshold value to remove the effect of specular reflection/crosstalk of sonar and a newly designed apparatus in which dirt cover (glass cover) and air blower are coupled to remove the influence of dirt, rain and humidity.

This proposed approach is tested in different environmental conditions, and to verify the consistency of the proposed approach, qualitative and quantitative analyses are carried out, which shows 42.5 per cent improvement in the probability value of occupied cells in the generated grid map.

The proposed ADWSRS approach reduced the effect of harsh environmental conditions such as fog, rain and smoke to generate efficient mapping of the environment, which may be implemented in diverse applications such as autonomous navigation, localization, path planning and mapping.

The purpose of this paper is to introduce and discuss 11 strategies and 11 sets of tools to provide a knowledge background on how native people of Iran have come up with innovative solutions to create a sustainable and comfortable living environment within the confinement of their homes, in harsh environment of Iran’s hot-arid and hot-humid regions.

These strategies include density, building orientation, introversion, design for four seasons, using local materials, using the ground’s thermal capacity, natural wind induced ventilation, using walls’ thickness and porosity, Panãm (insulation), using special native additive elements and integration of water and plants into the building. Discussed tools include water, courtyard, Showãdãn, Bahãr-khãb, roof, korsi room, ratio and Pãyãb, Sardãb and Howz-khãneh, Shanãshil, Bãdgir and Eivãn.

In conclusion, interrelations between these strategies and tools are illustrated in order to provide a collection of guidelines and inspirations for those involved in the building industry in Iran and Middle East to come up with innovative solutions for creating a sustainable and comfortable living environment in this region’s climates.

This paper provides a collection of guidelines and inspirations for those involved in the building industry in Iran and Middle East to come up with innovative solutions for creating a sustainable and comfortable living environment in this region’s climates.

The purpose of this paper is to improve the operation and maintenance intelligence of power systems, and summarize the transmission line robots and their key technologies. High-voltage power cables are important channels for power transmission systems. Their special geographical environment and harsh natural environment can lead to many different faults. At present, such special operations in dangerous and harsh environments are performed manually, which have not only high labor intensity and low work efficiency but also great personal safety risks.

For maintenance works that are far away from the tower, power outages are required. With the increasing evaluation of transmission quality and operational safety, and the urgent need for automation and operation of modern power systems, the contradiction between this manual operation and modern high-quality power transmission has become increasingly prominent. An effective method to replace the manual maintenance work is to use the mobile robot to carry the operation manipulator and its end tool, that is, the live maintenance robot.

Some achievements have been made in the key technologies of live maintenance robots, the work to be done to meet the basic requirements of complex and changeable line environment and practical application. Based on the existing research results of live overhaul robot, the follow-up research will focus on the practical application needs and the frontier of scientific and technological development, and truly realize the human–machine integration between live overhaul robot–human working environment. Only in this way can the robot better serve the operation and maintenance of the power system.

This paper reviews the system platform, operation function, structural characteristics and key technologies involved in the power cable robot, and the combination of live maintenance robots and modern high-tech such as big data and cloud computing is also given, and finally, the future development direction of the special operation robot is pointed out.

The purpose of this paper is to compare the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments and ultimately to provide basis and recommendations for the durability design of reinforced concrete (RC) structures.

Slag concrete specimens mixed with four kinds of rust inhibitors and coated with four kinds of surface strengthening materials were corroded by seawater exposure for 365 days, and the key parameters of chloride ion diffusion were obtained by testing. Then a new service life prediction model, based on the modified model for chloride ion diffusion and reliability theory, was applied to analyze the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments.

Rust inhibitors and surface strengthening materials can effectively extend the service life of RC structures through different effects on chloride ion diffusion behavior. The effects of rust inhibitors and surface strengthening materials on the service life extension of RC structures adhered to the following trend: silane material > cement-based permeable crystalline waterproof material > hydrophobic plug compound > spray polyurea elastomer > water-based permeable crystalline waterproof material > calcium nitrite > preservative > amino-alcohol composite.

Using a new method for predicting the service life of RC structures, the attenuation law of the service life of RC structures under the action of rust inhibitors and surface strengthening materials in tropical marine environments is obtained.

This paper aims to explore how police officer rank affects the relation between the extent of the code of silence and views of discipline fairness.

In 2005, 150 police supervisors and 450 line officers from East Bohemia, the Czech Republic were surveyed, regarding crucial components of police integrity.

Supervisor and line officer codes of silence are similar; whenever the codes differ, the supervisor code seems to be narrower. The majority of line officers and supervisors provided similar assessments of the expected discipline; they disagreed only regarding a small number of scenarios. The results clearly show a direct relation between how strongly police officers adhere to the code of silence and the way they view disciplinary fairness, regardless of their supervisory status.

The survey included only police officers from East Bohemia in the Czech Republic.

The methodology can be utilized by police administrators to explore the contours of the code of silence in their agencies, police officers' views about appropriate and expected discipline, as well as the relation between the police officers' willingness to tolerate misconduct in silence, and their perceptions of the fairness of the expected discipline.

Studies exploring the relation between the code of silence and discipline fairness are rare. This study contributes to this scarce literature along two dimensions: first, it provides an in‐depth analysis of the relation between the extent of the code of silence and views of discipline fairness in an emerging democracy; and second, it explores the effect of police officer rank on this relation.

This paper aims to give an overview about the state of wireless passive surface acoustic wave (SAW) gas sensor used in the detection of chemical vapor. It also discusses a variety of different architectures including delay line and array sensor for gas detection, and it is considered that this technology has a good application prospect.

The authors state the most of the wireless passive SAW methods used in gas sensing, such as CO2, CO, CH4, C2H4, NH3, NO2, et al., the sensor principles, design procedures and technological issues are discussed in detail; their advantages and disadvantages are also summarized. In conclusion, it gives a prospect of wireless passive SAW sensor applications and proposes the future research field might lie in the studying of many kinds of harmful gases.

In this paper, the authors will try to cover most of the important methods used in gas sensing and their recent developments. Although wireless passive SAW sensors have been used successfully in harsh environments for the monitoring of temperature or pressure, the using in chemical gases are seldom reported. This review paper gives a survey of the present state of wireless passive SAW sensor in gas detection and suggests new and exciting perspectives of wireless passive SAW gas sensor technology.

The authors will review most of the methods used in wireless passive SAW sensor and discuss the current research status and development trend; the potential application in future is also forecasted.

The authors will review most of the methods used in wireless passive SAW sensor and discuss the current research status and development trend; the potential application in future is also forecasted.

For many years, the concern over the use of plastic encapsulated microcircuits (PEMs) has been their capability to survive in harsh environments over a long term with continuous or intermittent operation. The issues centred around operational life limitation, due to failure mechanisms associated with internal corrosion, wires and wire bonds, and surface effects, It has now been conclusively demonstrated that best commercial practices will ensure that PEMs made using best commercial materials, processes, and quality techniques will permit devices to perform reliably in the most severe environments. Missile systems are low volume production items, which use relatively few microcircuits. They are required to operate for very short times after being unpowered (dormant) for very long times (10 to 20 years) and exposed to humidity, temperature cycle, and mechanical shock. This paper will address reliability concerns and provide data from studies which were performed to determine if PEMs could survive such long‐term unbiased applications. These studies include analysis of PEMs (some date coded 1968) from inventory or various storage locations and from applications where the electronic modules containing PEMs were stored for 10‐12 years in various environments. Regardless of the storage conditions, the significant factor is that these early vintage commercial grade PEMs, without screening or incoming inspection, survived assembly and extended storage.

This study uses the notions of institutional harshness and uncertainty avoidance in the home country to explain the choice between direct and indirect exporting strategies by emerging market firms.

This study is based on a dataset of 23,256 observations on firms from 32 countries spread over 11 years (2006–2016). Since only some firms undertake exports, the Heckman procedure is used to control for sample self-selection. In the first stage, we predict which firms will choose to export, and, in the second stage, we examine the factors driving the choice made by firms involved in exports between direct and indirect exports strategies.

The analyses reveal that firms are more likely to choose direct exports when institutional harshness is high and when they are from countries with low uncertainty avoidance. We also find that the strength of the relationship between institutional harshness and the choice of direct exports is moderated at high levels of uncertainty avoidance.

While this study's empirical models account for many firm-level factors as well as home country differences discussed in the literature, we acknowledge there could be other temporal, firm or country idiosyncratic factors not included in our analysis driving the key choices examined in the paper.

This study makes three contributions to exporting literature. First, it highlights the drivers of the choice between direct and indirect exports. This choice is an important facet of exporting strategy and has received scant attention in prior IB research. Second, it demonstrates how the choice between direct and indirect exports is impacted by the degree of the home country's institutional harshness and uncertainty avoidance. Third, it offers insights on how the interaction of formal and informal home market institutional factors influences export strategy.

Localization is one of the critical issues in Ocean Internet of Things (OITs). The existing research results of localization in OITs are very limited. It poses many challenges due to the difficulty of deploy beacon accurately, the difficulty of transmission distance estimation in harsh ocean environment and the underwater node mobility. This paper aims to provide a novel localization algorithm to solve these problems.

This paper takes the ship with accurate position as a beacon, analyzes the relationship between underwater energy attenuation and node distance and takes them into OITs localization algorithm design. Then, it studies the movement regulation of underwater nodes in the action of ocean current, and designs an Energy-aware Localization Algorithm (ELA) for OITs.

Proposing an ELA. ELA takes the ship with accurate position information as a beacon to solve the problem of beacon deployment. ELA does not need to calculate the information transmission distance which solves the problem of distance estimation. It takes underwater node movement regulation into computation to solve the problem of node mobility.

This paper provides an ELA based on the relationship between propagation energy attenuation and node distance for OITs. It solves the problem of localization in dynamic underwater networks.