Enhancing the sense of presence of participants is an important issue in terms of security awareness for remote collaboration in extended reality.However,conventional methods are insufficient to be aware of remote sit...Enhancing the sense of presence of participants is an important issue in terms of security awareness for remote collaboration in extended reality.However,conventional methods are insufficient to be aware of remote situations and to search for and control remote workspaces.This study pro-poses a spatial multi-presence system that simultaneously provides multiple spaces while rapidly exploring these spaces as users perform collaborative work in an extended reality environment.The proposed system provides methods for arranging and manipulating remote and personal spaces by creating an annular screen that is invisible to the user.The user can freely arrange remote participants and their workspaces on the annular screen.Because users can simultaneously view various spaces arranged on the annular screen,they can perform collaborative work while simultaneously feeling the presence of multiple spaces and can be fully immersed in a specific space.In addition,the personal spaces where users work can also be arranged through the annular screen.According to the results of the performance evaluations,users participating in remote collaborative works can visualize the spaces of multiple users simultaneously and feel their presence,thereby increasing their understanding of the spaces.Moreover,the proposed system reduces the time to perform tasks and gain awareness of the emergency in remote workspaces.展开更多
With the rapid development of immersive multimedia technologies,360-degree video services have quickly gained popularity and how to ensure sufficient spatial presence of end users when viewing 360-degree videos become...With the rapid development of immersive multimedia technologies,360-degree video services have quickly gained popularity and how to ensure sufficient spatial presence of end users when viewing 360-degree videos becomes a new challenge.In this regard,accurately acquiring users’sense of spatial presence is of fundamental importance for video service providers to improve their service quality.Unfortunately,there is no efficient evaluation model so far for measuring the sense of spatial presence for 360-degree videos.In this paper,we first design an assessment framework to clarify the influencing factors of spatial presence.Related parameters of 360-degree videos and headmounted display devices are both considered in this framework.Well-designed subjective experiments are then conducted to investigate the impact of various influencing factors on the sense of presence.Based on the subjective ratings,we propose a spatial presence assessment model that can be easily deployed in 360-degree video applications.To the best of our knowledge,this is the first attempt in literature to establish a quantitative spatial presence assessment model by using technical parameters that are easily extracted.Experimental results demonstrate that the proposed model can reliably predict the sense of spatial presence.展开更多
The analysis of company data useful for economic decisions,if not interpreted in an overall view of the company situation,can lead to wrong conclusions.This is the case when a company has to choose between several sal...The analysis of company data useful for economic decisions,if not interpreted in an overall view of the company situation,can lead to wrong conclusions.This is the case when a company has to choose between several sales options for one or more products in the presence of a limiting factor.The continuation of the investigation often denies the initial analysis.Not everything is as it appears,therefore,at the beginning of the deepening of the data useful for economic decisions.As it is well known,the choices of profitability concerning the planning of the sale of company products take place,at least in the majority of cases,through the determination of the contribution margin,i.e.the profitability margin connected to the individual goods/services sold by the companies(selling price net of variable costs).The contribution margin can be determined with four objectives:(1)Determination of the yield of the single product,net of variable costs only.In this case,the margin defines unitary,from net product yield to unitary contribution margin.(2)Determination of the return on total sales of an individual product,net of variable costs.In this hypothesis,reference is made to the first level(or gross)contribution margin.(3)Determination of the ability of the individual product to contribute to the coverage of fixed costs common to the company.This margin is determined net of special product variable and fixed costs.This aggregate is defined as a Level II(or semi-gross)margin.(4)Determination of the useful value in the planning choices in case of presence of scarce productive factors.In this case,it must identify the so-called unitary margin for low factor.Here we will only deal with the problem of the use of the contribution margin in the presence of rare factors.To complete the analysis,below are some very brief considerations regarding,respectively,the unitary,level I,and level II contribution margin in order to better understand where the problem of the most convenient choice of income is located in the event of the presence of rare production factors,especially in an environment characterized by a plurality of sales options.展开更多
We extend Bespalov-Talanov (B-T) theory on small-scale self-focusing (SSSF) to include vector effect of a very narrow intense laser beam with application of the vector self-focusing model. The gain spectrum for pertur...We extend Bespalov-Talanov (B-T) theory on small-scale self-focusing (SSSF) to include vector effect of a very narrow intense laser beam with application of the vector self-focusing model. The gain spectrum for perturbations is obtained by using the standard linear instability analysis. It is shown that the influence on SSSF of vector effect is closely related to the beam width. For a very narrow beam, the role played by vector effect becomes significant, it reduces the fastest growing frequency and the maximum growth rate, and shortens the frequency range for perturbation growing, and thus deviates the gain spectrum from that of B-T theory.展开更多
With the rapid global proliferation of the Internet and telecommunication networks, online education, one form of distance education is currently becoming the fastest growing trend of domestic and international educat...With the rapid global proliferation of the Internet and telecommunication networks, online education, one form of distance education is currently becoming the fastest growing trend of domestic and international education. A major challenge to designing online learning is the development of appropriate means to facilitate the social environment that is critical for higher order learning in many disciplines. In many online learning designs, the majority of resources are channeled to web interface design and technology, while little or no resources are devoted to facilitating the teaching and learning process, the negotiation of meaning and the validation of knowledge among peers and instructors that depends on a conducive socio-cultural environment and adequate learner support.展开更多
BACKGROUND Surgical intervention is usually a traumatic event that causes stress and anxiety in the pediatric patient and the family environment.To reduce the harmful effects of presurgical anxiety,parental presence d...BACKGROUND Surgical intervention is usually a traumatic event that causes stress and anxiety in the pediatric patient and the family environment.To reduce the harmful effects of presurgical anxiety,parental presence during induction of anesthesia(PPIA)is one of the more notable interventions used in medical centers.However,data on this measure are difficult to evaluate and often face resistance from healthcare staff.AIM To analyze the perception of the healthcare workers after the implementation of a PPIA program.METHODS A survey was developed and sent by email to all the healthcare staff working in the children’s area of a tertiary hospital.It consisted of 14 items divided into positive aspects of PPIA and negative aspects of PPIA evaluated with the use of a Likert scale(1 to 5).The demographics of the respondents were included in the data collected.The answers to the questions were interpreted through the Net Promoter Score(NPS).The statistical analysis compared the differences in the responses to each question of the survey made by the different groups of health personnel included.RESULTS A total of 141 surveys were sent out,with a response rate of 69%.Of the total number of responses,68%were from women and 32%from men.The average age of the participants was 42.3±10.6 years.As for the positive questions about the PPIA,83%had an NPS>50,and only one had a score between 0 and 50,which means that the quality of the service was rated as excellent or good by 100%of the respondents.On the other hand,100%of the negative questions about the PPIA had a negative NPS.Responses to the question“PPIA increases patient safety”were significantly different(P=0.037),with a lower percentage of pediatric surgeons(70%)thinking that PPIA increased patient safety,compared with anesthesiologists(90%),nursing(92%),and other medical personnel(96%).CONCLUSION The personnel who participated in the PPIA program at our center were in favor of implementation.There were no validated arguments to support worker resistance to the development of the PPIA.展开更多
Evolution of spatial distribution of charged particulates under the action of an external force is investigated.It is found that starting from a homogeneous Maxwellian distribution of particulates,clusters can form an...Evolution of spatial distribution of charged particulates under the action of an external force is investigated.It is found that starting from a homogeneous Maxwellian distribution of particulates,clusters can form and aggregate.The evolution process,as well as the asymptotic number and configuration of the clusters formed,depends strongly on the strength of the external force.The particulates in most of the final clusters are in the crystal state,as can also be deduced from the corresponding velocity and auto-correlation functions.展开更多
基金supported by“Regional Innovation Strategy(RIS)”through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(MOE)(2021RIS-004).
文摘Enhancing the sense of presence of participants is an important issue in terms of security awareness for remote collaboration in extended reality.However,conventional methods are insufficient to be aware of remote situations and to search for and control remote workspaces.This study pro-poses a spatial multi-presence system that simultaneously provides multiple spaces while rapidly exploring these spaces as users perform collaborative work in an extended reality environment.The proposed system provides methods for arranging and manipulating remote and personal spaces by creating an annular screen that is invisible to the user.The user can freely arrange remote participants and their workspaces on the annular screen.Because users can simultaneously view various spaces arranged on the annular screen,they can perform collaborative work while simultaneously feeling the presence of multiple spaces and can be fully immersed in a specific space.In addition,the personal spaces where users work can also be arranged through the annular screen.According to the results of the performance evaluations,users participating in remote collaborative works can visualize the spaces of multiple users simultaneously and feel their presence,thereby increasing their understanding of the spaces.Moreover,the proposed system reduces the time to perform tasks and gain awareness of the emergency in remote workspaces.
基金supported in part by ZTE Industry⁃University⁃Institute Coop⁃eration Funds.
文摘With the rapid development of immersive multimedia technologies,360-degree video services have quickly gained popularity and how to ensure sufficient spatial presence of end users when viewing 360-degree videos becomes a new challenge.In this regard,accurately acquiring users’sense of spatial presence is of fundamental importance for video service providers to improve their service quality.Unfortunately,there is no efficient evaluation model so far for measuring the sense of spatial presence for 360-degree videos.In this paper,we first design an assessment framework to clarify the influencing factors of spatial presence.Related parameters of 360-degree videos and headmounted display devices are both considered in this framework.Well-designed subjective experiments are then conducted to investigate the impact of various influencing factors on the sense of presence.Based on the subjective ratings,we propose a spatial presence assessment model that can be easily deployed in 360-degree video applications.To the best of our knowledge,this is the first attempt in literature to establish a quantitative spatial presence assessment model by using technical parameters that are easily extracted.Experimental results demonstrate that the proposed model can reliably predict the sense of spatial presence.
文摘The analysis of company data useful for economic decisions,if not interpreted in an overall view of the company situation,can lead to wrong conclusions.This is the case when a company has to choose between several sales options for one or more products in the presence of a limiting factor.The continuation of the investigation often denies the initial analysis.Not everything is as it appears,therefore,at the beginning of the deepening of the data useful for economic decisions.As it is well known,the choices of profitability concerning the planning of the sale of company products take place,at least in the majority of cases,through the determination of the contribution margin,i.e.the profitability margin connected to the individual goods/services sold by the companies(selling price net of variable costs).The contribution margin can be determined with four objectives:(1)Determination of the yield of the single product,net of variable costs only.In this case,the margin defines unitary,from net product yield to unitary contribution margin.(2)Determination of the return on total sales of an individual product,net of variable costs.In this hypothesis,reference is made to the first level(or gross)contribution margin.(3)Determination of the ability of the individual product to contribute to the coverage of fixed costs common to the company.This margin is determined net of special product variable and fixed costs.This aggregate is defined as a Level II(or semi-gross)margin.(4)Determination of the useful value in the planning choices in case of presence of scarce productive factors.In this case,it must identify the so-called unitary margin for low factor.Here we will only deal with the problem of the use of the contribution margin in the presence of rare factors.To complete the analysis,below are some very brief considerations regarding,respectively,the unitary,level I,and level II contribution margin in order to better understand where the problem of the most convenient choice of income is located in the event of the presence of rare production factors,especially in an environment characterized by a plurality of sales options.
基金Supported by the High Technology Research and Development Program of China(Grant No.863-416-5).
文摘We extend Bespalov-Talanov (B-T) theory on small-scale self-focusing (SSSF) to include vector effect of a very narrow intense laser beam with application of the vector self-focusing model. The gain spectrum for perturbations is obtained by using the standard linear instability analysis. It is shown that the influence on SSSF of vector effect is closely related to the beam width. For a very narrow beam, the role played by vector effect becomes significant, it reduces the fastest growing frequency and the maximum growth rate, and shortens the frequency range for perturbation growing, and thus deviates the gain spectrum from that of B-T theory.
文摘With the rapid global proliferation of the Internet and telecommunication networks, online education, one form of distance education is currently becoming the fastest growing trend of domestic and international education. A major challenge to designing online learning is the development of appropriate means to facilitate the social environment that is critical for higher order learning in many disciplines. In many online learning designs, the majority of resources are channeled to web interface design and technology, while little or no resources are devoted to facilitating the teaching and learning process, the negotiation of meaning and the validation of knowledge among peers and instructors that depends on a conducive socio-cultural environment and adequate learner support.
文摘BACKGROUND Surgical intervention is usually a traumatic event that causes stress and anxiety in the pediatric patient and the family environment.To reduce the harmful effects of presurgical anxiety,parental presence during induction of anesthesia(PPIA)is one of the more notable interventions used in medical centers.However,data on this measure are difficult to evaluate and often face resistance from healthcare staff.AIM To analyze the perception of the healthcare workers after the implementation of a PPIA program.METHODS A survey was developed and sent by email to all the healthcare staff working in the children’s area of a tertiary hospital.It consisted of 14 items divided into positive aspects of PPIA and negative aspects of PPIA evaluated with the use of a Likert scale(1 to 5).The demographics of the respondents were included in the data collected.The answers to the questions were interpreted through the Net Promoter Score(NPS).The statistical analysis compared the differences in the responses to each question of the survey made by the different groups of health personnel included.RESULTS A total of 141 surveys were sent out,with a response rate of 69%.Of the total number of responses,68%were from women and 32%from men.The average age of the participants was 42.3±10.6 years.As for the positive questions about the PPIA,83%had an NPS>50,and only one had a score between 0 and 50,which means that the quality of the service was rated as excellent or good by 100%of the respondents.On the other hand,100%of the negative questions about the PPIA had a negative NPS.Responses to the question“PPIA increases patient safety”were significantly different(P=0.037),with a lower percentage of pediatric surgeons(70%)thinking that PPIA increased patient safety,compared with anesthesiologists(90%),nursing(92%),and other medical personnel(96%).CONCLUSION The personnel who participated in the PPIA program at our center were in favor of implementation.There were no validated arguments to support worker resistance to the development of the PPIA.
基金Supported by the Natural Science Foundation of Zhejiang Province under Grant No LY15A050001the National Natural Science Foundation of China under Grant Nos 11247007 and 11374262the Open Fund of the State Key Laboratory of High-Field Laser Physics at SIOM
文摘Evolution of spatial distribution of charged particulates under the action of an external force is investigated.It is found that starting from a homogeneous Maxwellian distribution of particulates,clusters can form and aggregate.The evolution process,as well as the asymptotic number and configuration of the clusters formed,depends strongly on the strength of the external force.The particulates in most of the final clusters are in the crystal state,as can also be deduced from the corresponding velocity and auto-correlation functions.
