User's Viewpoint Research Articles

A user-oriented performance comparison of video hosting services

Internet streaming is responsible for a significant fraction of Internet traffic. It has been reported to account up to 70% of peak traffic in North American fixed access networks, and this figure is expected to reach 80% by 2020 [1]. Regarding such a killer service of the Internet, much has been discussed regarding if and how video hosting providers violate or may violate neutrality principles, in order to give users a “better” service compared to their competitors or other services. In this paper, we provide a contribution to this discussion studying three video hosting providers (i.e. YouTube, Vimeo, and Dailymotion). Specifically, we analyze their delivery infrastructures, including where the servers that provide videos are located, and the performance from a user viewpoint. To assess the performance, we measure throughput and RTT as experienced by users watching real videos of different popularity from several locations around the world and at different day hours.We uncover the performance differences of these providers as a function of the different variables under control and move a step forward to understand what causes such differences. We also study the changes in the infrastructures and related performance over time, performing different measurement campaigns over different years.Our results allow to understand what are the real performance users currently get from these providers and if the performance differences observed can be due or considered as a violation of network neutrality principles.

Selective patient and public involvement: The promise and perils of pharmaceutical intervention for autism.

BackgroundGuidelines suggest the patient community should be consulted from the outset when designing and implementing basic biomedical research, but such patient communities may include conflicting views. We examined how engagement occurred in one such instance.ObjectiveOur objective was to scrutinize patient and public involvement (PPI) by a pan‐European biomedical consortium working to develop drugs to treat autism. We aimed to use this as an example to illustrate how PPI has been utilized in biomedical research.Setting, participants and analysisTwo public events, one in the UK and one in Denmark were conducted as part of the consortium's on‐going PPI activities in 2014 and 2015. Sixty‐six individuals submitted written comments on the consortium's research after these events. The textual data produced were analysed using a thematic approach. Approximately 71% of respondents reported themselves to be adults on the autism spectrum or parents of children with autism.ResultsThe themes identified illustrated major differences between some community concerns and the biomedical research agenda. While treating autism per se. was seen as problematic by some, treating specific co‐occurring problems was seen as helpful in some circumstances. The biomedical consortium selected PPI with a limited user viewpoint at its outset and more widely once basic research was on‐going.DiscussionThis case illustrates what we term “selective PPI” where only a sympathetic and/or limited patient viewpoint is included. Findings highlight the perils of using selective PPI to legitimise scientific endeavours, and the possibilities for constructive dialogue.

Perceptions of autonomous vehicles: Relationships with road users, risk, gender and age

Fully automated self-driving cars, with expected benefits including improved road safety, are closer to becoming a reality. Thus, attention has turned to gauging public perceptions of these autonomous vehicles. To date, surveys have focused on the public as potential passengers of autonomous cars, overlooking other road users who would interact with them. Comparisons with perceptions of other existing vehicles are also lacking. This study surveyed almost 1000 participants on their perceptions, particularly with regards to safety and acceptance of autonomous vehicles. Overall, results revealed that autonomous cars were perceived as a “somewhat low risk“ form of transport and, while concerns existed, there was little opposition to the prospect of their use on public roads. However, compared to human-operated cars, autonomous cars were perceived differently depending on the road user perspective: more risky when a passenger yet less risky when a pedestrian. Autonomous cars were also perceived as more risky than existing autonomous trains. Gender, age and risk-taking had varied relationships with the perceived risk of different vehicle types and general attitudes towards autonomous cars. For instance, males and younger adults displayed greater acceptance. Whilst their adoption of this autonomous technology would seem societally beneficial – due to these groups’ greater propensity for taking road user risks, behaviours linked with poorer road safety – other results suggested it might be premature to draw conclusions on risk-taking and user acceptance. Future studies should therefore continue to investigate people’s perceptions from multiple perspectives, taking into account various road user viewpoints and individual characteristics.

Efficient Visibility Determination in Urban Scenes Considering Terrain Information

In this article, we introduce a novel occlusion culling method working on the server side to provide real-time navigation on web-based systems. Nowadays, virtual navigation in urban environments is a rising trend in several contexts such as tourism, GPS navigation systems, and video games. A city environment is usually associated with a complex data model that is better stored, maintained, and updated on a server system. Mobile devices are regular clients in these cases, demanding this information in a fast, reliable, and engaging way. Even though these gadgets have been increasing their capabilities in computation and visualization, the bottleneck is still the transmission of information over the network. The advantage of urban environments is that, from a user viewpoint, only a small portion of the scene is visible. This feature makes crucial the use of occlusion culling techniques working on the server side in order to transmit to the client side only the small set of visible elements compared to the whole scene. The input data are the city geometry from the 2D cadastral information system, the building textures, and DEM (Digital Elevation Model) files with the urban terrain features. In a first stage, the process creates a 2.5D urban model with all these data in preprocessing time. Then the client provides the user location point, and the server sends back the exact portion of visible city. This approach is implemented using polar diagrams for visibility determination and LOD (Level of Detail) techniques for further geometry reduction.

Thermal and Performance Analysis of a Gasification Boiler and Its Energy Efficiency Optimization

The purpose of this study was to determine a method for multi-parametric output regulation of a gasification boiler especially designed for heating or for hot water heating in buildings. A new method of regulation is offered, namely more parametric regulation via proportional-integral-derivative (PID) controllers that are capable of controlling the calculated values of pressure, temperature and fan speed. These values of pressure, temperature and fan speed are calculated in a completely new way, and calculations of setpoints for determination of optimal parameters lead to an increase in boilers efficiency and power output. Results of measurements show that changes at the mouth of the stack draft due atmospheric influences occur in times with high intensity and high frequency, while power parameters, or boiler power output amplitudes and fan speed automatically “copy” those changes proportionally due to instantaneous fan speed changes. The proposed method of regulation of the gasification boiler power output according to the technical solution enables a simple, cheap, express and continuous maintenance of high power output at low concentrations of the exhaust gases of the gasification boilers from the viewpoint of the boiler user, as well as from the perspective of development and production it allows a continuous control monitoring of these parameters.

A Procedural Content Generation-Based Framework for Educational Games: Toward a Tailored Data-Driven Game for Developing Early English Reading Skills

Automated content generation for educational games has become an emerging research problem, as manual authoring is often time consuming and costly. In this article, we present a procedural content generation framework that intends to produce educational game content from the viewpoint of both designer and user. This framework generates content by means of genetic algorithm, and thereby offers designers the ability to control the process of content generation for various learning goals according to their preferences. It further takes into consideration how the content can adapt according to the skill of the users. We demonstrate effectiveness of the framework by way of an empirical study of human players in an educational language learning game aiming at developing early English reading skills of young children. The results of our study confirm that users’ performance measurably improves when game contents are customized to their individual ability, in contrast to their improvement in uncustomized games. Moreover, the results show that the lowest proficiency participants demonstrated greater improvements in performance while playing the customized game than did the more highly proficient participants.

Motor experience influences object knowledge.

An object's perceived readiness-for-action (e.g., its size, the degree of rotation from its canonical position, the user's viewpoint) can influence semantic knowledge retrieval. Yet, the organization of object knowledge may also be affected by body-specific sensorimotor experiences. Here, we investigated whether people's history of performing motor actions with their hands influences the knowledge they store and retrieve about graspable objects. We compared object representations between healthy right- and left-handers (Experiment 1), and between unilateral stroke patients, whose motor experience was changed by impairment of either their right or left hand (Experiment 2). Participants saw pictures of graspable everyday items with the handles oriented toward either the left or right hand, and they generated the type of grasp they would employ (i.e., clench or pinch) when using each object, responding orally. In both experiments, hand dominance and object orientation interacted to predict response times. In Experiment 1, judgments were fastest when objects were oriented toward the right hand in right-handers, but not in left-handers. In Experiment 2, judgments were fastest when objects were oriented toward the left hand in patients who had lost the use of their right hand, even though these patients were right-handed prior to brain injury. Results suggest that at least some aspects of object knowledge are determined by motor experience, and can be changed by new patterns of motor experience. People with different bodily characteristics, who interact with objects in systematically different ways, form correspondingly different neurocognitive representations of the same common objects. (PsycINFO Database Record

Optimized camera handover scheme in free-viewpoint video streaming

Free-viewpoint video (FVV) is a promising approach that allows users to control their viewpoint and generate virtual views from any desired perspective. The individual user viewpoints are synthesized from two or more camera streams and correspondent depth sequences. In case of continuous viewpoint changes, the camera inputs of the view-synthesis process must be changed in a seamless way, to avoid the starvation of the viewpoint synthesizer algorithm. Starvation occurs when the desired user viewpoint cannot be synthesized with the currently streamed camera views, and thus, the FVV playout interrupts. In this paper, we propose three different camera handover schemes (TCC, MA, and SA) based on viewpoint prediction to minimize the probability of playout stalls and find the trade-off between the image quality and the camera handover frequency. Our simulation results show that the introduced camera switching methods can reduce the handover frequency with more than 40%, and hence, the viewpoint synthesis starvation and the playout interruption can be minimized. By providing seamless viewpoint changes, the quality of experience can be significantly improved, making the new FVV service more attractive in the future.

Intersecting Contexts: Understanding Rural Utah Veterans’ Experiences with Accessing VA Health Care

AbstractSince the passage of the Rural Veterans Care Act of 2006 research has focused on health care provider issues with less attention given to individual and contextual factors that contribute to the remaining service gap. Adopting the health care user's viewpoint, we focus on two questions: How do health care users perceive access to health care, and which contextual factors are relevant to explaining the failure of recent efforts to increase access by rural veterans? We collected detailed data through focus groups and individual interviews involving veterans and knowledgeable community members in four rural areas of Utah. Framing the analysis of interview data using the sociospatial approach reveals key dimensions of several contexts that affect rural veterans’ access to health care: the historical period of military service that influences attitudes toward use of Veterans Administration health care and access to specialists, regulations of regionally and locally organized insurance coverage that affects access to and coordination of health care, and local social aspects of rural communities that inform use of specific health care sources. These dimensions provide new insights into the conditions that contribute to variations in the vulnerability of rural Utah veterans.

容積バンクの成立要因及び課題の解明

“Transfer of development right (TDR)” has been considered as an important institution for the urban regeneration since recently. The TDR system is first released in 1990 in Taipei city. Today, there are many TDR institutions in Taipei, Taiwan. The important point is that all of them could be utilized overall the Taipei city, so the integrity between TDR and existing urban plan is important. In this study, we first summarize several TDR institutions including Monument TDR, Urban plan TDR and Dihua Street TDR in Taipei city. Then we make clear the position and characteristic of TDR within the existing urban plan system. Then, we focus on compare the difference of new type of Urban plan TDR called Floor area bank (FAB) started in Taipei since 2014 with previous TDR. We first clarify the system of Floor area bank in Taipei city and the reason why it was established as the substitute of existing TDR institution. The difference between FAB-TDR and existing urban plan TDR is that, by donating land for public facility to Taipei city government, developers can get floor area same as the value of that land in the past. However, developers should pay the “Floor area fee” to the “Floor Bank” (Taipei city government) to get the floor area, and the amount of floor area will be decided by the “Urban design committee of Taipei city” based on the application of developer. We consider that all TDR institution is a kind of instrument for obtaining extra floor area. Actually, developers use several institutions for obtaining extra floor area including TDR and other institutions, for example, “Bonus floor area” institution is also one of that. However, the difference between TDR and Bonus floor area is that the floor area acquired from TDR is permanent. To protect the right of accepting site of TDR, certificate of TDR will be issued by Taipei city government. Besides, accepting site will also be recorded in the online zoning system of Taipei city. We then make clear the characteristic of FAB-TDR by operating the actual utilization cases. From the macro level, FAB-TDR actually solves the issues of unbalanced location of receiving site in the previous TDR institutions by operating total volume control. From the micro level, we can see how urban design committee plays an important role on controlling the nearby community of receiving site. What' more, by operating the evaluation of “Floor area fee” and the deliberation of urban design committee, it shortens the process of using FAB-TDR. Basically, it takes about 8 months. Finally, we summarize the key factor of the success of FAB-TDR and summarize the issues of it today. From the viewpoint of Taipei city government, FAB-TDR should consider about to provides some incentive for the user. From the viewpoint of user (developer), the cost of FAB-TDR is too expensive. From the viewpoint of appraisal, appraisal method of “Floor area fee” should be modified.

Changing quality of recycled fiber material. Part 1. Factors affecting the quality and an approach for characterisation of the strength potential

The paper recycling sector has undergone major changes in recent years, particularly regarding the quantity and quality of various materials processed. Material originating from board grades will increasingly dominate the recycling market as the use of printing papers decreases and the amount of non-fiber elements increases. Users of recycled fiber material have to overcome three main challenges: price, quality, and availability. This paper focuses on the quality dilemma in terms of measurement needs and possibilities from the user viewpoint. It includes a discussion of the factors causing deterioration in the quality of paper used for recycling. Today, the average fiber age is low compared to what the fibers can tolerate. Therefore, the characteristic phenomena in the paper recycling loop are not caused by the degradation of individual fibers, but by a blending process in which different fiber grades and non-fiber components are blended in a non-optimal way. A novel method is introduced in this article for evaluating the quality of recycled fiber material using a new parameter, the fiber integrity value. Part 2 of this paper will focus on the application of this new parameter and demonstrates its correlation with paper properties.

Gaussian Light Field: Estimation of Viewpoint-Dependent Blur for Optical See-Through Head-Mounted Displays.

We propose a method to calibrate viewpoint-dependent, channel-wise image blur of near-eye displays, especially of Optical See-Through Head-Mounted Displays (OST-HMDs). Imperfections in HMD optics cause channel-wise image shift and blur that degrade the image quality of the display at a user's viewpoint. If we can estimate such characteristics perfectly, we could mitigate the effect by applying correction techniques from the computational photography in computer vision as analogous to cameras. Unfortunately, directly applying existing calibration techniques of cameras to OST-HMDs is not a straightforward task. Unlike ordinary imaging systems, image blur in OST-HMDs is viewpoint-dependent, i.e., the optical characteristic of a display dynamically changes depending on the current viewpoint of the user. This constraint makes the problem challenging since we must measure image blur of an HMD, ideally, over the entire 3D eyebox in which a user can see an image. To overcome this problem, we model the viewpoint-dependent blur as a Gaussian Light Field (GLF) that stores spatial information of the display screen as a (4D) light field with depth information and the blur as point-spread functions in the form of Gaussian kernels, respectively. We first describe both our GLF model and a calibration procedure to learn a GLF for a given OST-HMD. We then apply our calibration method to two HMDs that use different optics: a cubic prism or holographic gratings. The results show that our method achieves significantly better accuracy in Point-Spread Function (PSF) estimations with an accuracy about 2 to 7 dB in Peak SNR.

Health sciences librarians off the radar.

The library environment has undergone tremendous change through the years and with that change, the profession has had to adapt. These seemingly simple phrases written more than forty years ago continue to be as meaningful and applicable today as they were when written: “like everything else, libraries and library methods are changing at an increasing rate,” and “‘new things' have been and are happening in your field, and, indeed, some of these new trends seem to have come upon us quickly and, in some instances, have become drastic enough to threaten the very existence of the relatively small, professionally-supported medical library” [1]. Many health sciences libraries have adapted to accelerated technological advancements, fragmented collection acquisition models, altered space allocations, and modified user viewpoints. Particularly, health sciences libraries in hospitals have been profoundly impacted with library closures, bringing forth new thoughts related to value, adaptation, and change. In essence, this seemingly new trend of closures experienced today may not be so new after all, and the question that must be asked is, how has the health sciences hospital library continued to survive through the years?

Potensi Kebijaksanaan Kontrak Pemeliharaan Mesin dalam Menunjang Keberhasilan Mekanisme Industri Pertanian

In this paper we discuss a mathematical model of maintenance policy for certain type of agricultural equipments. It is assumed that the equipments are repairable and sold with two-dimensional warranty, i.e. a warranty with two scales of limit, such as the age of the equipment and the usage of the equipment. As an example in the case of automobile, the warranty is cease whenever the age of the automobile reaches 5 years or its mileage reaches 50.000 km, whichever occurs first. The model is intended to provide the best contract-based preventive maintenance (PM) strategy chosen from available options. A method to determine the optimal cost of service contract, both from user and producer view points, is presented. Numerical simulations reveal that the resulting optimal strategy depends on the level of the consumer usage pattern. In this paper we show that the selection of optimal policy is potential in supporting the performance of mechanization in agricultural industry in terms of choosing the best strategy to maintain agricultural equipments effectively (is able to reduce the failure rate of the equipment) with a minimal cost.

Title of the Paper:Measuring Service Quality of Public Transport Operator in Pune City, Maharashtra India Uses the Critical Incident Technique

This study explores the service quality of public Transporters from user's viewpoints using different techniques such as, the critical incident technique (critical incident technique), e-mail inquiries, and unstructured interviews. The researcher recruited 48 participants, 24 female and 24 male who are the frequent public Transport users. Different participants were asked to report positive and negative incidents or situations in relation to the services provided by their public Transporters mainly considering geographical area of Pune city of Maharashtra, India. This study utilized the conceptual themes of SERVQUAL, a model that has been used by many service industries for evaluating their public services. Data were collected and analyzed from e-mail inquiries and unstructured interviews. Results. Findings revealed that the positive incidents were slightly higher than the negative events. Also women transport users had more positive experiences than men. Further investigations of this study are provided. This study revealed that even though the participants reside in different areas, their positive and negative incidents reveal similar situations. Further research would be expanded to a larger study population and/or compare other public Public transport users outside the Pune. Another possibility could be could be looking the size of the Public transporters and their serving population.

Focused augmented mirror based on human visual perception

A mirror is used in various aspects of daily life; thus, most people can use a mirror-metaphor augmented reality (AR) system naturally, without wearing a head-mounted display or AR glasses. An augmented mirror, one of the mirror metaphor AR display, is considered a more appropriate system than video-based virtual mirror display for personalized and immersive interaction in AR because it can show a combined scene in which a rendered virtual world is superimposed on the reflected real world based the viewpoint of a user. In this paper, we propose a focused augmented mirror that implements both viewpoint and depth-of-field matchings. In particular, we design a focused augmented mirror by concentrating on how the depth-of-field influences human visual perception in the augmented mirror system. To compare the differences between the theoretical and practical results, we perform two types of experiments; calculating the focus measure of the combined image photographed at user's viewpoint and evaluating user experience with randomly selected non-expert people. In addition, we suggest an efficient user workspace that is limited by the tracker's geometric configuration and the target object's depth of field. Finally, we describe the physical limitation of our system and propose its solution as a future work.

Enabling consistent hand-based interaction in mixed reality by occlusions handling

A mixed reality environment, namely the space resulting from displaying virtual contents co-registered to the real space, represents an effective paradigm for applying the potential of virtual reality in the everyday life instead of having it confined within a computer screen. In this context, gesture-based interaction seems to be the most suited approach for human-machine interfacing. However, in order that interaction to be visually consistent, the tridimensional composition of the virtual objects onto the real background should be per-formed respecting the distance of each rendered pixel according to the user viewpoint. This paper describes a simple yet effective hand/finger-based interaction system and a virtual-to-real occlusion-handling approach, able to process in real time the stereoscopic video see-through stream to achieve pixel-wise z-order info, crucial to evaluating whether each rendered pixel should be displayed. The experiments confirm the efficacy of the proposed method in a simulation context.

Developing a stereoscopic CG system with motion parallax and interactive digital contents on the system for science museums

As we watch 3D objects and move around them, the appearance of the objects would change. This is called motion parallax and it is one of important depth cues. We develop an interactive stereoscopic CG system using motion parallax. This system follows the position of a user's view point, and generates 3DCG images for the view point every moment. As a result, the system can reproduce motion parallax and can synthesize stereoscopy without special equipments. Based on this system, we develop two interactive stereoscopic contents which would be used in science museums. One is a constellation viewer, in which we can observe constellations and planets from any positions, and can grasp positional relationships and 3D shapes of them. It is also possible to control the content with gestures. The other is a virtual 3D photocopy system. When we put physical 3D objects on a desk and remove them, we can observe virtual objects from any points as a stereoscopic 3DCG image based on motion parallax. We can feel the removed objects being left as they were. When the system scans moving objects, a stereoscopic 3DCG animation is synthesized and the user can observe it from any positions. It is also possible to interact with the 3DCG objects such as touching and deforming the 3DCG objects.

A viewpoint based extension of the common warehouse metamodel to support the user's viewpoint approach

Metadata integration and interoperability is still one of the leading problems facing the datawarehouse and the business analysis community. The Common Warehouse Metamodel CWM enables interoperability and easy interchange of warehouse and business information metadata between heterogeneous systems. However, a decisional process involves a variety of expert and novice users who manipulate several types of knowledge and know-how, each user exploits the process based on his preferences, needs and objectives. Currently, the CWM metamodel does not allow to model and to keep trace of users' experiences during the exploitation of the whole decisional process. In this paper, we extend the CWM in order to support its different users with a new entity that is viewpoints, which models and keeps trace of user preferences, objectives, and decisions made during the datawarehouse process. Our main objective is the capitalisation of users' experiences to enhance reusability of metadata and coordination between users.

Ruminant Digestive System Based Framework for Enhancing the Reliability and Availability of Cloud

In the last decade, the substantial increase in adoption of cloud computing has transformed the IT industry. From a user's viewpoint, the practically boundless scalability, the avoidance of up-front investments, and usage based payment schemes make cloud computing a very attractive option. Presently, almost all companies and individuals are utilizing the cloud for any of their purpose. Healthcare sector also understands the major advantages of cloud services and try to utilize the cloud computing. The cloud has some challenges or issues in cloud which affects the performance of the Healthcare applications in cloud. The Reliability of cloud services and Availability of cloud resources are considered as important challenges. We have already proposed three scheduling algorithms to improve the reliability and availability of cloud resources. In this paper we propose a new hybrid scheduling algorithm fit into our RDS framework to furthermore improve the performance.