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1.
Online dating continues to grow rapidly in popularity every day, yet the role of social competence in online dating behavior remains unclear. This study was designed to expand previous research and conduct a comprehensive investigation on how social competence is associated with college students’ online dating behaviors, perceptions, and attitudes. Two hypotheses were tested: The social compensation hypothesis (SCH)socially incompetent individuals would engage in more online dating, and the rich-get-richer hypothesis (RGRH)—socially competent individuals would use online dating more than their incompetent counterparts. The results showed that incompetent individuals, despite their ability to see benefits in online dating, did not show a favorable attitude towards online dating. They indicated a more frequent use of and a stronger preference for face-to-face dating compared to online dating, which contradicted the SCH. There were weak associations between competence traits and online dating behavior. Socially competent individuals perceived less benefit and showed less interest in online dating, which disconfirmed the RGRH.  相似文献   

2.
Petri net language is a powerful tool for describing dynamic behaviors of physical systems. However, it is not easy to obtain the language expression for a given Petri net especially a structure-complex net. In this paper, we first analyze the behaviors of S-nets, which are structure-simple. With the decomposition method based on a given index function on the place set, a given structure-complex Petri net can be decomposed into a set of structure-simple S-nets. With the language relationships between the original system and the decomposed subnets, an algorithm to obtain the language expression of a given structure-complex net system is presented, which benefits the analysis of physical systems based on the Petri net language.  相似文献   

3.
Canopy phenology plays a prominent role in determining the timing and magnitude of carbon uptake by many ecosystems. The Moderate Resolution Imaging Spectroradiometer (MODIS) Global Land Cover Dynamics product developed from the enhanced vegetation index (EVI) provides broad spatial and temporal coverage of land-surface phenology (LSP), and may serve as a useful proxy for the phenology of canopy photosynthesis. Here, we compare the MODIS growing season start and end dates (SOS and EOS) with the seasonal phenology of canopy photosynthesis estimated using the eddy covariance approach. Using 153 site-years obtained from the Ameriflux database, we calculated the SOS and EOS of gross primary production (GPP) and canopy photosynthesis capacity (CPC) for seven different boreal and temperate vegetation types. CPC is GPP at maximum radiation, estimated by fitting half-hourly GPP and radiation to a rectangular hyperbolic function. We found large mean absolute differences of up to 53 days, depending on vegetation type, between the phenology of canopy development and photosynthesis, indicating that remotely sensed LSP is not a robust surrogate of seasonal changes in GPP, particularly for evergreen needleleaf forests. This limited correspondence of ecosystem carbon uptake with the MODIS LSP product points to the need for improved remotely sensed proxies of GPP phenology.  相似文献   

4.
A parallel multithreaded program that is ostensibly deterministic may nevertheless behave nondeterministically due to bugs in the code. These bugs are called determinacy races, and they result when one thread updates a location in shared memory while another thread is concurrently accessing the location. We have implemented a provably efficient determinacy-race detector for Cilk, an algorithmic multithreaded programming language. If a Cilk program is run on a given input data set, our debugging tool, which we call the ``Nondeterminator,' either determines at least one location in the program that is subject to a determinacy race, or else it certifies that the program is race free when run on the data set. The core of the Nondeterminator is an asymptotically efficient serial algorithm (inspired by Tarjan's nearly linear-time least-common-ancestors algorithm) for detecting determinacy races in series-parallel directed acyclic graphs. For a Cilk program that runs in T time on one processor and uses v shared-memory locations, the Nondeterminator runs in O(T α(v,v)) time, where α is Tarjan's functional inverse of Ackermann's function, a very slowly growing function which, for all practical purposes, is bounded above by 4 . The Nondeterminator uses at most a constant factor more space than does the original program. On a variety of Cilk program benchmarks, the Nondeterminator exhibits a slowdown of less than 12 compared with the serial execution time of the original optimized code, which we contend is an acceptable slowdown for debugging purposes. Received November 11, 1997, and in final form September 21, 1998.  相似文献   

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Internet-of-things technologies enable service providers such as insurance companies to collect vast amounts of privacy-sensitive data on car drivers. This paper studies whether and how privacy concerns of car owners can be compensated by offering monetary benefits. We study the case of usage based car insurance services for which the insurance fee is adapted to measured mileage and driving behaviour. A conjoint experiment shows that consumers prefer their current insurance products to usage based car insurance. However, when offered a minor financial compensation, they are willing to give up their privacy to car insurers. Consumers find privacy of behaviour and action more valuable than privacy of location and space. The study is a first to compare different forms of privacy in the acceptance of connected car services. Hereby, we contribute to more fine-grained understanding of privacy concerns in the acceptance of digital services, which will become more important in the upcoming Internet-of-things era.  相似文献   

8.
From video games to virtual worlds on the World Wide Web, modern media are becoming increasingly spatial, with users traversing artificial spaces and experiencing a kind of immersion known as “spatial presence.” But how do these media induce spatial presence? Are the affordances for movement provided by these technologies responsible for this illusion? Or do narratives that accompany them persuade us to suspend disbelief and transport ourselves into a virtual space? We explore these theoretical questions by pitting the navigability affordances of a video game against narrative transportation and examining their relative contributions to the formation of spatial presence in a virtual reality context. Results from a large experiment (N = 240) reveal that the narrative actually detracts from spatial presence while traversibility (in the form of greater degrees of steering motion) enhances it even without invoking a mental model of the portrayed environment. Theoretical and practical implications are discussed.  相似文献   

9.
We add to the investments literature by employing new techniques to estimate asset performance. We estimate a data envelopment analysis based efficiency score that allows for direct comparison between ex-post efficiency rankings and test the ex-ante relevance of such scores by including them into asset pricing models. We find that knowing the fund efficiency score can help explain time-series returns. When efficiency is included in an asset pricing model, the absolute value of the average mispricing error is decreased, which we take as evidence of the explanatory power of efficiency scores. But more importantly, we show that efficacy scores can be used as next period predictors of stock returns. In addition, we further use the efficiency scores to differentiate between the performance of constrained and unconstrained investment assets, as in the case of socially responsible investments. Our findings give robustness to the literature on constrained investments showing significant underperformance of socially and responsible investments.  相似文献   

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The ergonomics aspects of the design of a domestic telephone are outlined as a case study. The main usage points investigated were: handset relationship to ear and mouth together with adequate finger clearance at the cheek; general comfort when picking up and holding the handset; replacing the handset correctly in order to operate the hook-switch; establishing an acceptable compromise for dial and keypad angle at 15 degrees ; and devising a wall mounted unit.  相似文献   

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This study examined whether computerized dynamic testing by utilizing a robot would lead to different patterns in children's (aged 6–9 years) potential for learning and strategy use when solving series‐completion tasks. The robot, in a “Wizard of Oz” setting, provided instructions and prompts during dynamic testing. It was found that a dynamic training resulted in greater accuracy and more correctly placed pieces at the post‐test than repeated testing only. Moreover, children who were dynamically trained appeared to use more heuristic strategies at the post‐test than their peers who were not trained. In general, observations showed that children were excited to work with the robot. All in all, the study revealed that computerized dynamic testing by means of a robot has much potential in tapping into children's potential for learning and strategy use. The implications of using a robot in educational assessment were stressed further in the discussion.  相似文献   

14.
A natural extension of cloud services is to extend platform independence via virtualization to a security model. For security as a service to be a viable cloud offering, customers must be able to establish their own security policies and risk framework. Today, cloud customers must purchase, install, and configure the antiviral, antispyware, antimalware, and so on, services in their host environment. However, if cloud providers offered security as a service in these virtualized environments, customers could integrate these security measures into their risk profile to ensure that the cloud risk posture is acceptable for their mission. By leveraging the service delivery model, a cloud can deliver security as a service as part of a virtualized infrastructure as a pay-for-service offering. This configuration lets customers selectively choose the countermeasures they wish to implement as dictated by their risk profile. The practicality of this security-as-a-service approach will continue to evolve with technology. In spring 2009, VMware released the VMsafe API, which supports third-party security applications in the hypervisor (a virtual-machine monitor). If VMsafe performs as claimed, it will enable the cloud-computing environment to support security as a service. The VMsafe API offers the immediate opportunity to begin the long-needed transition of cloud computing from a trusted environment to a secured environment.  相似文献   

15.
This article explores a robotogenetic model of empathetic understanding of another mind as one of the capabilities required in human–robot social interactions. The term robotogenetic means that we implement a possible ontogeny (i.e., developmental process) of the social capability onto a robotic embodiment with a certain phylogenetic background (i.e., innate prerequisites). First, we look into infants development of social and communicative skills, especially of empathetic understanding of others. We then consider two fundamental abilities, namely eye-contact and joint attention, as the prerequisites for this cognitive development. Then in psychological experiments using robots that are capable of eye-contact and joint attention, we observe how people, especially infants and children, attribute mental states to the robots. Based on these investigations, we consider a possible mechanism of empathy which is based on the spatiotemporal coordination of attention and bodily movement between the self and another.This work was presented in part at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January 24–26, 2003  相似文献   

16.
In this work, we present the concept, design and implementation of a new software to visualize and segment 3-dimensional medical data. The main goal was to create a platform that would allow trying out new approaches and ideas while staying independent from hardware and operating system, being especially useful for interdisciplinary research groups. A special focus will be given on fast and interactive volume visualization, and a survey on the use of Virtual Reality (VR) and especially haptic/force feedback in medical applications will be provided.  相似文献   

17.
There is a strong relationship between evaluation and methods for automatically training language processing systems, where generally the same resource and metrics are used both to train system components and to evaluate them. To date, in dialogue systems research, this general methodology is not typically applied to the dialogue manager and spoken language generator. However, any metric for evaluating system performance can be used as a feedback function for automatically training the system. This approach is motivated with examples of the application of reinforcement learning to dialogue manager optimization, and the use of boosting to train the spoken language generator.  相似文献   

18.
Roger Normann 《AI & Society》2005,19(4):520-542
Summary  The article locates work on regional development, and in particular action research, within the context of debates on neo-liberalism and democracy. The learning regions approach is explored, but the scale of the challenges to overcome is emphasised.
Roger NormannEmail:
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19.
This paper provides an introduction to several problems and techniques related to controlling periodic motions of dynamical systems. In particular, we consider planning periodic motions and designing feedback controllers for orbital stabilization. We review classical and recent design methods based on the Poincaré first-return map and the transverse linearization. We begin with general nonlinear systems and then specialize to a class of underactuated mechanical systems for which a particularly rich structure allows many of the problems to be solved analytically.  相似文献   

20.
Can we determine a high resolution protein structure quickly, say, in a week? I will show this is possible by the current technologies together with new computational tools discussed in this article. We have three potential paths to explore:
  • X-ray crystallography. While this method has produced the most protein structures in the PDB (Protein Data Bank), the nasty trial-and-error crystallization step remains to be an inhibitive obstacle.
  • NMR (Nuclear Magnetic Resonance) spectroscopy. While the NMR experiments are relatively easy to do, the interpretation of the NMR data for structure calculation takes several months on average.
  • In silico protein structure prediction. Can we actually predict high resolution structures consistently? If the predicted models remain to be labeled as “predicted”, and these structures still need to be experimentally verified by the wet lab methods, then this method at best can serve only as a screening tool.
I investigate the question of “quick protein structure Determination” from a computer scientist point of view and actually answer the more relevant question “what can a computer scientist effectively contribute to this goal”.  相似文献   

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