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In this paper, we propose a formation control algorithm for multi-USVs according to COLREGs. First, we applied the Dynamic Window Approach algorithm that can reflect the kinematic characteristics for the path movement of USVs. Then, we propose a virtual structure-based virtual leader-follower method that applies the advantages of leader-follower and virtual structure methods among conventional formation control algorithms for stability. Next, we proposed a collision avoidance algorithm according to all COLREGs when encountering an opposing ship by adding COLREGs situational conditions to the virtual leader, and finally confirmed the feasibility of the proposed method through simulation.

High-harmonic radiation can be generated when an ultra-intense laser beam is reflected from an over-dense plasma, known as a plasma mirror. It is considered a promising technique for generating intense attosecond pulses in the extreme ultraviolet and X-ray wavelength ranges. However, a solid target used for the formation of the over-dense plasma is completely damaged by the interaction. Thus, it is challenging to use a solid target for applications such as time-resolved studies and attosecond streaking experiments that require a large amount of data. Here we demonstrate that high-harmonic radiation can be continuously generated from a liquid plasma mirror in both the coherent wake emission and relativistic oscillating mirror regimes. These results will pave the way for the development of bright, stable, and high-repetition-rate attosecond light sources, which can greatly benefit the study of ultrafast laser-matter interactions.

The on-board voltage regulator in the DDR5 memory module is required to resiliently supply current at large load transient events and alleviate output noise at the same time. We present an adaptive on-time (AOT) buck regulator with a turbo dual-phase interleaving logic for stable regulation and on-time control with dithered pseudo-constant switching frequency to suppress output harmonics by 6dB. The voltage regulator delivers up to 10A with a peak efficiency of 92.5% and covers 10A/μs steep load transients.

In this paper, we propose a new framework for detecting the unauthorized dumping of garbage in real‐world surveillance camera. Although several action/behavior recognition methods have been investigated, these studies are hardly applicable to real‐world scenarios because they are mainly focused on well‐refined datasets. Because the dumping actions in the real‐world take a variety of forms, building a new method to disclose the actions instead of exploiting previous approaches is a better strategy. We detected the dumping action by the change in relation between a person and the object being held by them. To find the person‐held object of indefinite form, we used a background subtraction algorithm and human joint estimation. The person‐held object was then tracked and the relation model between the joints and objects was built. Finally, the dumping action was detected through the voting‐based decision module. In the experiments, we show the effectiveness of the proposed method by testing on real‐world videos containing various dumping actions. In addition, the proposed framework is implemented in a real‐time monitoring system through a fast online algorithm.

In order to deliver medical products (medicines, vaccines, blood packs, etc.) in time for needed areas, a method of transporting goods using drones is being studied. However, temperature-sensitive medical products may decay due to outside temperature changes. The time required to transport over the distance may vary a lot as well. As a result, the likelihood of the goods deteriorating is very high. There is a need for a study on cargo bay to prevent this and to protect the medical goods. In this paper, in order to protect the temperature sensitive medical goods, the inside cargo bay is equipped with the cooling fan device and the electric heating elements. These elements can be monitored and controlled according to the user’s discretion. By using the web server built inside the cloud server, the temperature can be controlled in real-time from anywhere without the limitation of distance. We built the proposed device, and installed it on the drone cargo bay. The test results show that the cargo bay can be temperature-controlled, and the setting can be maintained over a great distance. The user can watch the temperature variations during the transport and ascertain the goodness of the medical supply with the data. It is expected that such development can greatly enhance the utility of the drone operations, especially for the medical supply transport applications.

The drone was developed with the use of unmanned aircraft systems in the initial military sector based on the combination of aerospace technology and information and communication technologies in a variety of usability, including the civilian sectors. Developed for the field of reconnaissance, it is used in both civilian and police sectors as traffic monitoring and high altitude reconnaissance missions. It is used in broadcasting and surveillance, while continuously expanding into the areas of courier delivery and rescue missions. Based on the convergence of aviation technology such as various SW, sensor and flight control to utilize unmanned system and information communication technology, commercialization of related technology is being developed as a very diverse route. In this paper, we propose and manufacture of a VTOL UAV. Design process referred to the VTOL development process that has been devised by us, and actual building of a UAV also applied the same VTOL development concept. In order to understand the aerodynamic characteristics of the aircraft, we have applied the aerodynamic design theory and used the CAE method that can replace the actual wind tunnel test. We tested the selection method and criteria for the internal modules that make up the UAV, and we were able to assemble the product. FW coding of flight control computer was conducted for VTOL control. In addition, we developed a LTE communication module for the long distance flight, and carried out flight experiments with GCS to observe and respond to the flight situation from the ground. Flight test results showed that stable transition flight was possible with broadband. We could see that the actual performance results were met, compared to our development target values.

Recently, the need for exoskeleton robots has been increased due to the advancement of robotic technologies and changes in the concept of how the robots can be utilized in direct contact with human bodies. The robots, once only used on the factory floor, are now becoming a part of human bodies, which provides the unprecedented level of muscle power boost and the increase of running speed. If used very carefully, the exoskeleton robots can be also used for patients’ rehabilitation. The exoskeleton robots have many potential application areas; hence most advanced countries are currently developing various types of exoskeleton robots. Those robots can be classified into two major categories, namely the rigid type and the soft type. Each type has own advantages and disadvantages, while the carrying load capacity and the actuation speed can be quite different. There are also many technical difficulties in order to use the exoskeleton robots in the field. The aim of this study is, therefore, to introduce the trends of exoskeleton robot development in advanced countries, while providing the analysis on the technical merits and downside of robot types. The comparison chart also indicates the major technical directions, in which the future technology will be headed for, such as the improved robot response characteristics by employing advanced sensors and artificial intelligence. The robots are becoming smarter, lighter, and more powerful. It is foreseeable that the wearable robots can be a part of human life in the very near future.

The integrated Mission Planning System (MPS) of Unmanned Surface Vehicle (USV) refers to the process which can recognize, decide, plan situations and carry out missions, such as human beings, for all incidental or complex events occurring at sea. In the actual operating environment, it is necessary to develop a simulation software environment and analyze, verify it in advance so as to make an appropriate mission plan considering equipment, sensor, fuel, and other available resources. The existing USV mission planning process methodology has several limitations in the analysis of USV missions because the scenario to be tested is limited and autonomy of USV is not considered sufficiently. To overcome these problems, we constructed a process that considers various missions and is more autonomous, and an integrated environment in which to experiment. In this study, we designed a multi-agent based USV Integrated Mission Planning System and modeled each component. In addition, we constructed the USV remote operation S/W based on M&S that user can experiment with the modeled process and verified the usefulness of the developed system through simulations.

For contingencies occurring in a complex marine environment, Unmanned Surface Vehicle (USV) has to recognize the situation and decide behaviors, and plan the following actions through the Integrated Mission Planning Process. Therefore, researches are actively being carried out about it. However, since it is difficult to test the actual USV with the mission planning process, it is necessary to develop a virtual experimental environment based on Modeling & Simulation (M&S). In this study, we developed an integrated simulation environment capable of simulating and analyzing the overall mission of USV. In Part I, we modelled the USV Integrated Mission Planning Process and in Part II, we developed an experimental framework and interface for loading them. In addition, we verified the suitability of this model through scenarios and defined the Mission of Effectiveness (MOE) concept for USV mission analysis.

The 3D vehicle trajectory in complex traffic conditions such as crossroads and heavy traffic is practically very useful in autonomous driving. In order to accurately extract the 3D vehicle trajectory from a perspective camera in a crossroad where the vehicle has an angular range of 360 degrees, problems such as the narrow visual angle in single-camera scene, vehicle occlusion under conditions of low camera perspective, and lack of vehicle physical information must be solved. In this paper, we propose a method for estimating the 3D bounding boxes of vehicles and extracting trajectories using a deep convolutional neural network (DCNN) in an overlapping multi-camera crossroad scene. First, traffic data were collected using overlapping multi-cameras to obtain a wide range of trajectories around the crossroad. Then, 3D bounding boxes of vehicles were estimated and tracked in each single-camera scene through DCNN models (YOLOv4, multi-branch CNN) combined with camera calibration. Using the abovementioned information, the 3D vehicle trajectory could be extracted on the ground plane of the crossroad by calculating results obtained from the overlapping multi-camera with a homography matrix. Finally, in experiments, the errors of extracted trajectories were corrected through a simple linear interpolation and regression, and the accuracy of the proposed method was verified by calculating the difference with ground-truth data. Compared with other previously reported methods, our approach is shown to be more accurate and more practical.

For video understanding, namely analyzing who did what in a video, actions along with objects are primary elements. Most studies on actions have handled recognition problems for a well‐trimmed video and focused on enhancing their classification performance. However, action detection, including localization as well as recognition, is required because, in general, actions intersect in time and space. In addition, most studies have not considered extensibility for a newly added action that has been previously trained. Therefore, proposed in this paper is an extensible hierarchical method for detecting generic actions, which combine object movements and spatial relations between two objects, and inherited actions, which are determined by the related objects through an ontology and rule based methodology. The hierarchical design of the method enables it to detect any interactive actions based on the spatial relations between two objects. The method using object information achieves an F‐measure of 90.27%. Moreover, this paper describes the extensibility of the method for a new action contained in a video from a video domain that is different from the dataset used.

A novel model for trajectories and semantic regions (sest-hiHMM) is proposed.A sticky version of sest-hiHMMs is proposed for reducing redundant semantic regions.An extended definition of semantic regions covers actual regions, not sets of points.Our models concern the temporal dependency of observations in a trajectory.Our models retrieve reasonable semantic regions from a real trajectory dataset. With an increasing attempt of finding latent semantics in a video dataset, trajectories have become key components since they intrinsically include concise characteristics of object movements. An approach to analyze a trajectory dataset has concentrated on semantic region retrieval, which extracts some regions in which have their own patterns of object movements. Semantic region retrieval has become an important topic since the semantic regions are useful for various applications, such as activity analysis. The previous literatures, however, have just revealed semantically relevant points, rather than actual regions, and have less consideration of temporal dependency of observations in a trajectory. In this paper, we propose a novel model for trajectory analysis and semantic region retrieval. We first extend the meaning of semantic regions that can cover actual regions. We build a model for the extended semantic regions based on a hierarchically linked infinite hidden Markov model, which can capture the temporal dependency between adjacent observations, and retrieve the semantic regions from a trajectory dataset. In addition, we propose a sticky extension to diminish redundant semantic regions that occur in a non-sticky model. The experimental results demonstrate that our models well extract semantic regions from a real trajectory dataset.

In light of the increasing trend of the use of the product–service system (PSS), tools that can help to analyse complex relationships among products, services and technologies and furthermore support decision-making during their planning are needed. To meet these needs, this study proposes a design structure matrix (DSM)-based technology roadmap (TRM) approach and a case study on mobile services is conducted. While PSS planning may involve a number of teams and organisations, the DSM-based TRM can help with such complex collaborative technology planning and hence lead to better performance. Methodologically, this is one of the first attempts to link DSM and TRM, both of which are widely used in planning stages, and thus is expected to contribute to the advances in TRM methodologies. In practice, this study describes an overall roadmapping process for the PSS, thus providing worthwhile guidelines available to organisations that are in charge of the TRM.

Recently, the market for drones is growing rapidly. Commercial UAVs (Unmanned Aerial Vehicles, or drones) are increasingly being used for various purposes, such as geographic survey, rescue missions, inspection of industrial facilities, traffic monitoring and delivery of cargos and goods. In particular, the drones have great potential for life-saving operations. A missing person, for example, can be rapidly and effectively searched using a drone in comparison with the conventional search operations. However, there is no commercially available rescue UAV until now. The motivation for this study is to design an unmanned aerial vehicle capable of vertical takeoff and landing, while containing a high power propellant apparatus in order to lift a heavy cargo that contains rescue materials (such as water, food, and medicine). We used the EDF (Electric Ducted Fan) technology as opposed to the conventional motor and prop combination. The EDF can produce the power about three times higher than the motor-prop combination. This became suitable for transportation of rescue goods, and can be widely used in rescue operations in natural environments. Based on these results, the UAV for rescue material transport capable of heavy vertical takeoff and landing is developed, including airframe, flight control computer and GCS (ground control station).

Advanced countries around the world are spurring the development of Unmanned Surface Vehicles (USVs) that can operate autonomously at marine environment. The key enabling technology for such USVs is the mission planning system (MPS) that can autonomously navigate through the harsh waters. The MPS not only has the functions for the navigation, but also has the capabilities, such as obstacle avoidance, malfunction corrections, dealing with unexpected events, return home functions, and many other eventualities that cannot be programmed in advance. The autonomy levels are increasingly moving higher and it is foreseeable that the trend will continue in the future. The main purpose of this paper is the analysis of the MPS onboard the USVs, in terms of the categories, functions, and technological details. Also, we analyze the case study of autonomous mission planning control systems in various fields and introduce the features that constitute the critical functionalities of the mission planning systems.

In recent years, because of the development of marine military science technology, there is a growing interest in the unmanned systems throughout the world. Also, the demand of Unmanned Surface Vehicles (USVs) which can be autonomously operated without the operator intervention is increasing dramatically. The growing interests lie in the facts that those USVs can be manufactured at much lower costs, and can be operated without the human fatigue, while can be sent to the hostile or quite dangerous areas that are inherently unhealthy for human operators. The utilization and the deployment of such vessels will continue to grow in the future. In this paper, along with the technological development of unmanned surface vehicles, we investigate and analyze the cases of already developed platforms and identify the trends of the technological advances. Additionally, we suggest the future directions of development.

Recently, the surge in the interests in unmanned aerial vehicles has soared dra-matically worldwide due to many potential benefits foreseen by this technology. The most widespread use of the commercial drones is a multi-copter form of unmanned aerial vehicle, because of its vertical takeoff and landing (VTOL) capability. However, due to the structural characteristics, it has a disadvantage that the flight time is quite short, which is typically ranging between 15 to 30 minutes. The fixed wing type of unmanned aerial vehicles has a longer flight time and duration, but it is not easy to secure a safe landing space, especially in the city areas. For this reason, demand for vertical fixed take-off and landing aircraft is rapidly increasing throughout the world. This study analyzes the trends and recent development of global VTOL technology and provides a direction into which the current state of the technology should be heading. By comparing the advantage and disadvantage of various VTOP propulsion types, we can clearly identify the most effective form of VTOL propulsion types. Such analysis will be highly beneficial to the drone researchers and scientists in terms of future development.

Fixed wing unmanned aerial vehicles typically have longer running (flight) time than multicopers, but runways are needed. Because it is difficult to expect a wide runway in the city area, the great need is there to develop a vertical takeoff and landing (VTOL) type fixed-wing UAV that does not require any runway. In addition, our goal was to develop a VTOL plane that contains a stable transit flight characteristic. To achieve this goal, we have designed and developed a test plane and the flight parameters have been extensively tested. For the airframe design, the carbon-bar method was selected for vertical takeoff and landing, and the 11-way method was adopted through dynamics analysis. We assembled the airframe and made a prototype using the Pixhawk flight computer. The developed VTOL plane shows a very smooth transition flight. It is expected that the VOTL UAV will be widely used in the city area in the future for various purposes, such as cargo delivery and emergency medical supply delivery.

Most aircraft simulators are manufactured separately for each model because the structure and flight characteristic of each model is different. However, light aircrafts are somewhat similar in terms of form and structure. In addition, from the flight schools’ point of view, it is not economically beneficial to purchase and maintain light aircraft simulators for each different aircraft type. Globally, there are four types of light aircraft models that are most widely used for basic flight training. If all four models are separately selectable within a single flight simulator, there will be a lot of economic benefits in terms of reducing the purchasing costs as well as the reduction of pilot training costs. In this regard, this study aims at developing the multi-purpose variable-type simulator technology so that it can train four different aircraft types using only a single simulator. The utility of simulator is divided into the use of flight training and the use of leisure time. The flight characteristics are analyzed for each model type to emulate the actual aircraft. It is anticipated that the developed simulator can be produced at a lower cost while occupying less floor space and using less electric energy than the previous one.

In recent years, the weapon systems have been changing drastically because of the advancement of science technology and the change of military concept of combat. There is an unmanned system at the center of all those changes. Especially, in case of maritime environment, as the center stage of combat has changed from ocean to coastal areas, it is difficult for the existing naval forces to effectively operate in shallow waters. Therefore, unmanned underwater vehicles (UUVs) are being required at an increasing pace. In this paper, we analyze the characteristics of already developed UUVs, which are the key unmanned system of the marine battlefield environment in the future. Through the analysis of development cases and the investigation of the essential technologies, the critical design issues of UUVs are elaborated. We also suggest the future directions of the UUV technologies based on the case analysis.

Today, the growth of aerospace industry has led to the development of modular overhead systems that can be applied to a wide variety of aircraft. It actually maximizes training effectiveness by working in a similar way as to the real aircraft maneuverability. Overhead system control device for aircraft simulator is developed as a module and integrated to the flight simulator. The developed system can replace the similar products imported from overseas at a much lower price, about one third of the imports, while maintaining the same level of functionality and the performance with the counterparts. This price advantage is the main motivation of this development, which is expected to enlarge the commercial training simulator market in our country. This development has been also funded by the government, and we invited several commercial airline pilots to test the equipment. The post operation interview revealed that the developed system at least matches or exceeds the performance of the imported products. With the development completed, it is ready for the commercial production and will help promote the expansion of flight training education at various aerospace universities in Korea.

The automated part quality inspection poses many challenges to the engineers, especially when the part features to be inspected become complicated. A large quantity of part inspection at a faster rate should be relied upon computerized, automated inspection methods, which requires advanced quality control approaches. In this context, this work uses innovative methods in remote part tracking and quality control with the aid of the modern equipment and application of support vector machine (SVM) learning approach to predict the outcome of the quality control process. The classifier equations are built on the data obtained from the experiments and analyzed with different kernel functions. From the analysis, detailed outcome is presented for six different cases. The results indicate the robustness of support vector classification for the experimental data with two output classes. Highlights This work uses innovative methods in e-quality with the application of SVM. Many potential benefits of e-quality control have been presented and instantiated. The classifier equations are built on the data obtained from the experiments. A detailed analysis is presented for six different case studies. The results indicate the robustness of proposed SVM classification.

Overall, this paper explains the related information about VTOL and trend of this technology worldwide. Also, it comes up with the distinction among VTOL and helicopter and fixed wing aircraft. This paper concentrates on domestic and international drones that utilize VTOL technology. Also, this paper gives the explanation about VTOL’s performance and object. Furthermore, this paper predicts the future of VTOL and which area this technology going to be used.

The importance of the aircraft is increasing gradually; among them it may be called Ground Control Station (GCS) receiving the highest expectations. In aspect of operation, operator’s workload and working speed are one of the most important factors. Thus, we need to compare Touch mode and Non Touch mode in order to improve workload and working speed. In this paper, we analyzed the differences of Touch mode and Non Touch mode about workload, working speed in operation of aircraft. Through NASA-TLX and Measured working time, quantified data were collected and an analysis of variance (ANOVA) was performed. According to experimental result, working speed and workload according to input mode showed significant difference. In ground operation, Touch mode is better than Non Touch mode about working speed and workload. In the Touch mode, the optimal value of lower display angle was selected as 60。 angle.

In Side-by-Side helicopter system, pilots and co-pilot occupy same place and make a community about instruments. So both pilots have a great interaction and communication compared with tandem helicopter. In our previous research, we found the TSD information is effected on mission conduction greatly. We also realized the new task assignment is required. To compensate for our previous research and find the optimal task assignment in side-by-side helicopter system, we set up the second experiment. We established the scenario and did some experiment. Measuring data is performance total time, killing rate, and pilot & gunner workload data similar to before experiment 1, and this project has a purpose about finding optimal task assignment and researching strong point than Tandem system using 1 & 2 experiment totally.

This research investigates the impact of changing weather conditions on the crew members who sit in a side-by-side cockpit, which is unusual for attack helicopters. Extensive review conducted by the authors fails to locate similar studies; hence a helicopter simulator is developed in order to conduct the experiments. The simulator represents the realistic flight characteristics as well as the digital cockpit instruments that contain the advanced mission equipment. During the experiments, a camcorder is used to record the pilots to accurately analyze the task completion time and the physical motions of both pilots. NASA-TLX is also used to collect the workload data to assess the impact of task assignments among the pilots. The analytical findings from this study will be instrumental in improving the cockpit design for enhanced mission effectiveness.

This study is a preparation phase for visualization of utilized information using ergonomic user interface and standardization of elements for anti-air radar screen. Therefore, we investigated the instances of anti-air radar screen for air defense weapon system for defense advanced country. Based on the collected data, we compared and analyzed the air defense weapon system radar screen design. In addition, we carry out a research for layout, configuration, standardization and design of the radar screen’s elements. Ultimately, it is essential to share a variety of battle field conditions such as enemy threat, enemy/friendly information, terrain information that can be effectively recognized. In this paper, we conduct case study for ergonomically development of automated/standardized radar screen. It is expected that this research improves the situational awareness and reduces the user’s task load.

This study addresses a critical problem in the control of process capability as to the positioning accuracy of vision-guided robot. Depending on the calibration accuracy, the process capability varies widely, which renders the precise control of assembly tasks difficult. Furthermore, some vision sensors prohibit the programming access to rectify the lens distortion effects, which even complicates the problem. This study proposes a method of circumventing the lack of programming access by implementing the lens optical center alignment. Three different calibration methods are compared as to the process capability, and the proposed method shows a very good accuracy. The method can be easily adopted on the shop floor since it doesn’t require a complex setup and mathematical derivation process. Therefore, the practitioners can benefit from the proposed method, while maintaining a high level of precision in terms of robot positioning accuracy.

Computing for human experience has become more important for understanding all of aspects of any interaction of human beings in the cyber, physical, and social environments. In particular, artificial intelligent technologies based on big data enable to understand natural language, enhance day to day human experience, and make a better decision. In this paper, we propose a method to classify unstructured text data on the Web into the five types of sensation features: sight (ophthalmoception), hearing (audioception), touch (tactioception), smell (olfacception), and taste (gustaoception). Even though sensation is the first process of human experience against the environments, the study of sensation information extraction is neglected due to lack of sensory expression and knowledge comparing with the sentimental analysis or opinion mining. We first define the sensation measurement that is assigned to each feature. Then, we identify which sensation feature has a strong influence on human perceptual experience in a specific topic of corpus. Finally, we evaluate our method by comparing with several baselines in terms of the accuracy.

In this paper, analog-and-digital hybrid beamformer design is considered for millimeter-wave (mmWave) wideband multi-user (MU) multiple-input single-output (MISO)-OFDM downlink systems, where a single common analog beamformer is used for all subcarriers while a separate digital beamformer is applied to each subcarrier. By applying a signal-to-leakage-plus-noise ratio (SLNR) approach, an efficient beamformer design algorithm based on a trace quotient is derived for joint design of the common analog beamformer and the separate digital beamformers.