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This paper aims to present experimental experience of heavy fuelling of a spark ignition crankcase scavenged two-stroke cycle unmanned aerial vehicle (UAV) engine, particularly focusing on the effects of compression ratio variation, and to cross-correlate with the results of fluid dynamic modelling of the engine and fuels used.

One-dimensional modelling of the engine has been conducted using WAVE software supported by experimental dynamometer testing of a spark ignition UAV engine to construct a validated computational model using gasoline and kerosene JET A-1 fuels.

The investigation into the effects of compression ratio variation via fluid dynamic simulation and experimental testing has allowed an assessment of the approach for improving heavy fuel operation of UAV engines using auxiliary transfer port fuel injection. The power level achieved with reduced compression ratio heavy fuel operation is equal to 15.35 kW at 6,500 revolutions per minute compared to 16.27 kW from the standard gasoline engine or a reduction of 5.7%.

The studied engine is specifically designed for UAV applications. The validation of the computational models to explore the effects of compression ratio and heavy fuel injection on the solution and cost is supported by experimental tests.

The application of auxiliary port fuel injection of heavy fuel and associated compression ratio optimisation offers an alternative approach to achieve the safety and logistical challenges of the single fuel policy for UAVs. The application of WAVE to simulate crankcase scavenged two-stroke cycle engines has been applied in very few cases. This study shows further exploratory work in that context.

The purpose of this paper is to perform a technical and economical analysis on the conversion of a regional turboprop platform for Airborne Early Warning and Control (AEW&C) missions by supposing installation of supplementary diesel turbo‐charged engines.

The problem has been approached by considering all issues related to conversion to AEW&C platform. Class II methods have been used for weight and drag estimations. Flight performances have been evaluated by using standard equations of flight mechanics. Costs have been evaluated by using a model developed by the authors.

As far as performances are concerned, it is possible to increase aircraft service ceiling of about 4,400 ft by installing auxiliary diesel engines in separate wing‐nacelles. The low specific fuel consumption (SFC) of diesel engines balances the reduction of mission endurance caused by the aerodynamic drag increment (i.e. additional drag of AEW radar antenna and new nacelles). The proposed solution is shown to have the best Effectiveness‐Cost performance in comparison with other AEW&C aircraft‐systems.

To convert regional turboprops to AEW&C platform by employing turbocharged diesel engines could be an interesting future perspective for aerospace companies interested in creating a new AEW&C market segment.

The proposed solution gives the possibility to reduce operating costs in the AEW&C mission field. The issue is actual due to typical high operating costs of AEW&C missions.

The digital construction transformation requires using emerging digital technology such as deep learning to automate implementing tasks. Therefore, this paper aims to evaluate the current state of using deep learning in the construction management tasks to enable researchers to determine the capabilities of current solutions, as well as finding research gaps to carry out more research to bridge revealed knowledge and practice gaps.

The scientometric analysis is conducted for 181 articles to assess the density of publications in different topics of deep learning-based construction management applications. After that, a thematic and gap analysis are conducted to analyze contributions and limitations of key published articles in each area of application.

The scientometric analysis indicates that there are four main applications of deep learning in construction management, namely, automating progress monitoring, automating safety warning for workers, managing construction equipment, integrating Internet of things with deep learning to automatically collect data from the site. The thematic and gap analysis refers to many successful cases of using deep learning in automating site management tasks; however, more validations are recommended to test developed solutions, as well as additional research is required to consider practitioners and workers perspectives to implement existing applications in their daily tasks.

This paper enables researchers to directly find the research gaps in the existing solutions and develop more workable applications to bridge revealed gaps. Accordingly, this will be reflected on speeding the digital construction transformation, which is a strategy over the world.

To the best of the authors’ knowledge, this paper is the first of its kind to adopt a structured technique to assess deep learning-based construction site management applications to enable researcher/practitioners to either adopting these applications in their projects or conducting further research to extend existing solutions and bridging revealed knowledge gaps.

Having been a promising visualization tool since 1950s, ironically, virtual reality is not widely used in the architectural design and evaluation process due to several constrains, such as the high cost of equipments and advanced programming skills required. This paper described the collaboration between design computing courses and architecture design studios that have been taught at Savannah College of Art and Design (SCAD) in 2004 and 2005. These courses explored several practical methods to integrate Low Cost Virtual Reality Aided Design (LC-VRAD) in the architectural design process. As a summary of the collaboration, this paper refers to three main aspects: (1) How to use game engine to design an affordable VR system in the ordinary studio environment. (2) How to integrate VR, into the design process, not only as a visualization tool, but also as a design instrument. (3) How to evaluate different methods of representing architectural models based on the efficiency of workflow, rendering quality and users' feedback.

Support by the Game and Interactive Design Department at SCAD, students in the School of Building Arts implemented two Low Cost VRAD methods in various design phases, starting from site analysis, schematic design, design development to the final presentation. Two popular game engines, Epic Game's Unreal engine and Director MX's Shockwave engine, were introduced to students to visualize their project in real-time. We discussed computer-aided design theories including the application of VR, as well as digital computing and human computer interaction. At the end of each quarter, feedbacks from students and faculties were collected and analyzed. These methods were revised and improved consistently across 2004 and 2005 academic year.

University archives (UA) are the bridge between the past and the present and serve as a beacon for highlighting the contribution of academic institutions to society. Although the UA topic was introduced and formalized in the 1950s, the scientific research interest has increased significantly in the past two decades. This paper aims to provide insights into the UA research topic during the previous 15 years.

The combination of two well-established methods for performing literature review was deployed, aiming to identify, select and assess the research documents. Based on the selection criteria, 49 documents presenting research efforts around the UA topic were finally examined from the Scopus citation index. The selected studies have been classified into three main topics: strategic management of UA and the derived challenges, the educational contribution of UA and the strategic information systems for UA.

Some of the main findings are the lack of well-defined administrative policies, the low level of awareness and archival consciousness within the universities, the inadequacy of university archivists’ educational and training background, the need to use UA for building relationships with alumni and society, and finally, the need for metadata standardization by the UA management systems.

As a literature review around UA has not been conducted before, the reader will gain insights into the methods and research designs that other scholars had already applied to designate useful findings and results.

Over the past decade, researchers have used unmanned aerial systems (UASs) in construction industry for various applications from site inspection to safety monitoring or building maintenance. This paper aims to assort academic studies on construction UAS applications, summarize logics behind using UAS in each application and extend understanding of current state of UAS research in the construction setting.

This research follows a systematic literature assessment methodology to summarize the results of 54 research papers over the past ten years and outlines the research trends for applying UASs in construction.

UASs are used in building inspection, damage assessment, site surveying, safety inspection, progress monitoring, building maintenance and other construction applications. Cost saving, time efficiency and improved accessibility are the primary reasons for choosing UAS in construction applications. Rotary-wing UASs are the most common types of UASs being used in construction. Cameras, LiDAR and Kinect are the most common onboard sensors integrated in construction UAS applications. The control styles used are manual, semi-autonomous and autonomous.

This paper contributes to classification of UAS applications in construction research and identification of UAS hardware and sensor types as well as their flying control systems in construction literature.

This paper aims to consider the question of changes brought to consumers’ trust and security issues by the implementation of the General Data Protection Regulation (GDPR) in electronic commerce.

Online shopping policies in Poland and Ukraine are compared from the perspective of four factors as follows: application of terms of service and privacy policy, usage of online payment systems, presence in price comparison engines and grade of secure sockets layer security certificates. Comparison is conducted within the framework of three research questions (complemented by eight hypotheses) set to reveal whether: policies of personal data protection and server security for online stores in both countries are the same; all online stores in both countries obey the existing e-commerce rules; e-commerce policies in the two countries differ significantly. The sample for analysis contains 40 Polish and 40 Ukrainian online stores, representing four industries, namely, electronics, entertainment, fashion and goods for children.

The research allowed to reveal major differences in the privacy policy of the two countries, caused, mainly, by the absence of GDPR in Ukraine. It also disclosed much stronger cooperation of online stores and price comparison engines in Poland compared to Ukraine. At the same time, research results allow to state that server security in both countries is on the same rather high level and that online stores use transparent and safe methods of online payment.

This research opens a way to other, expanded observations which will include more countries and larger scopes of data. Its main limitation is that GDPR influence is only studied in two countries, not in all countries where it is implemented.

This research contributes from security and trust perspectives by analyzing the situation in two countries as follows: the EU member (Poland) and a non-EU country (Ukraine). The value of exploring the situation of Ukrainian e-commerce consists of understanding how online stores function without implementing the GDPR. Observation of shopbots application allows drawing an important conclusion of the necessity for online stores to cooperate with such services. It was also revealed that consumers’ trust in both countries depends a lot on the payment methods applied by an online store and on the ease of use of these methods.