Energy-efficient and cost-effective web API invocations with transfer size reduction for mobile mashup applications

Recently, the proliferation of smartphones and the extensive coverage of wireless networks have enabled numerous mobile users to access Web resources with smartphones. Mobile mashup applications are very attractive to smartphone users due to specialized services and user-friendly GUIs. However, to offer new services through the integration of Web resources via Web API invocations, mobile mashup applications suffer from high energy consumption and long response time. In this paper, we propose a proxy system and two techniques to reduce the size of data transfer, thereby enabling mobile mashup applications to achieve energy-efficient and cost-effective Web API invocations. Specifically, we design an API query language that allows mobile mashup applications to readily specify and obtain desired information by instructing a proxy to filter unnecessary information returned from Web API servers. We also devise an image multi-get module, which results in mobile mashup applications with smaller transfer sizes by combining multiple images and adjusting the quality, scale, or resolution of the images. With the proposed proxy and techniques, a mobile mashup application can rapidly retrieve Web resources via Web API invocations with lower energy consumption due to a smaller number of HTTP requests and responses as well as smaller response bodies. Experimental results show that the proposed proxy system and techniques significantly reduce transfer size, response time, and energy consumption of mobile mashup applications.     

一种针对大规模网络图像的自动标注改善算法

在对网络图像进行索引时,人们往往利用网页中图像周围的文字作为其近似标注信息,但是这些文字信息质量不高,不足以良好地描述图像内容。该文提出一种综合利用图像视觉特征、相关文本信息以及词汇间语义关系的方法对这些不精确的文本信息进行改善,从而提高图像的索引和搜索质量。在大规模数据集上的实验证明了所提出的方法能够有效改善图像的标注。     

Media pattern exhibition mechanism via mobile devices

This paper describes a new methodology of pattern exhibition for digital media that can conceal an imperceptible but recognizable watermark on the media captured with mobile devices. From the human perception, the imperceptible watermark of marked media can preserve the fidelity and readability of the image’s content. With the designed, window-based histogram operation, the embedded pattern of the marked media can be exhibited and recognized visually. That is, the designed mechanism can satisfy the essentials of both visible and invisible watermarking techniques to promote significant pattern sharing and identification for mobile applications. Simulations demonstrate that the peak signal-to-noise ratio (PSNR) of the marked image is superior (around 50–70 dB) to many of the existing watermarking algorithms. The process is of low computational complexity, efficient and can be applied in the real world via mobile devices via inner histogram operation.     

Personal Trusted Devices for Web Services: Revisiting Multilevel Security

In this paper we revisit the concept of mandatory access control and investigate its potential with personal digital assistants (PDA). Only if applications are clearly separated and Trojans cannot leak personal information can these PDAs become personal trusted devices. Limited processing power and memory can be overcome by using Web services instead of full-fledged applications – a trend also in non-mobile computing. Web services, however, introduce additional security risks, some of them specific for mobile users. We propose an identification scheme that can be effectively used to protect privacy and show how this system builds upon a light-weight version of mandatory access control.     

Mobile Search With Multimodal Queries

The popularity of mobile devices, such as PDAs and SmartPhones, has grown rapidly over the last couple of years. Though most users still perform searches using desktop computers, it is expected that more and more people will also search the Web while they are on the move. In addition to text-based keyword queries, mobile devices can support richer and hybrid queries such as images, audio, video, and their combinations. In this paper, we will discuss mobile search systems that support image queries and audio queries, covering typical designs for mobile visual and audio search, as well as the opportunities and challenges. Specifically, we will present an in-depth study of two real systems we have developed: product image categorization and mobile ringtone search, which use image queries and audio queries, respectively. Experimental results on real-life data demonstrate their effectiveness and efficiency.     

基于移动设备的图像体视化系统

设计了一个基于移动设备的图像体视化系统,通过红蓝互补色眼镜,实现图像的立体显示,使用户可以使用移动设备随时随地体验立体图像。实验证明,提出基于移动设备的图像体视化技术具有使用简便易于实现的特点,其体视效果明显,易于观察,对于体视技术在移动设备的应用和研究具有一定的指导意义。     

Mobile computing technology at Vindigo

Developing widely useful mobile computing applications presents difficult challenges. On one hand, mobile users demand intuitive user interfaces, fast response times, and deep relevant content. On the other hand, mobile devices have limited processing, storage, power, display, and communication resources. Vindigo has taken a technology-intensive approach to meeting these challenges and has created personal navigation tools that many people find useful in their everyday lives. Vindigo's Palm OS application, introduced in March 2000, has hundreds of thousands of users and continues to attract new users rapidly. This article presents some of the technology behind Vindigo. To provide context, it first gives an overview of a typical user session. It then discusses special demands and constraints placed on mobile applications, and enumerates design principles drawn from these considerations. The rest of the article describes technology developed at Vindigo according to those principles. Throughout, it emphasizes techniques that have proven effective in delivering location-based services on today's handheld devices.     

Meeting human needs with new digital imaging technologies

It's a visual world. Images capture many people's thrills, emotions, and concerns. Art can shock or inspire, and family photos are some of our greatest treasures. It's not surprising that visual information is a vital component of the new computing. Most people depend on visual input to understand the world around them and as a basis for further creative activities. The popularity of visual media such as photos, short videos, and animations attests to their mainstream acceptance. Digital photos and image-laden Web pages have already become major computing applications, but users still want higher-resolution images and faster downloads     

基于Matlab的图像自动标注

图像自动标注在检索大量数字图像时起到关键作用,它能将图像的视觉特征转化为图像的标注字信息,为用户的使用及检索带来极大的方便。研究了图像自动语义标注方法,设计并实现了基于Matlab图像自动标注系统,能够提取图像颜色特征和纹理特征,与已标注图像进行相似性度量并标注出图像语义关键词     

Experience with adaptive mobile applications in Odyssey

In this paper, we present our experience with application-aware adaptation in the context of Odyssey, a platform for mobile data access. We describe three applications that we have modified to run on Odyssey – a video player, a Web browser, and a speech recognition system. Our experience indicates that it is relatively simple to incorporate applications into Odyssey, and that application source code is not always essential. Although our applications were built without knowledge of each other, Odyssey is able to run them concurrently without interference. However, our experience also exposes important areas of future work. Specifically, it reveals the difficulty of balancing agility with stability in adaptation, and emphasizes the need for controlled exposure of internal Odyssey state to users.     

Cloud-assisted Computing for Event-driven Mobile Services

Today, software developers for desktop computing build request and respond applications to do what end users tell them to do and answer what they ask. In mobile computing, software developers will need to develop sense and response applications that will interact with the end user. These applications will notify or ask users what they want based on what they have sensed or on a personal profile. Mobile cloud computing has the potential to empower mobile users with capabilities not found in mobile devices, combining different and heterogeneous data sets. In this work, we discuss the importance and challenges in designing event-driven mobile services that will detect conditions of interest to users and notify them accordingly.     

Optimization method for attribute-based cryptographic access control in mobile cloud computing

For the problem of secure data sharing and access control in mobile cloud,the drawback of traditional cryptographic access control schemes was deeply analyzed.Considering the truth that mobile devices were usually equipped with limited resources,an optimized attribute-based cryptographic access control scheme was proposed in this study.In the proposed scheme,a third party proxy was introduced into the system model,and the two-layer encryption method was applied.Combining traditional attribute-based encryption (ABE) algorithm with multi-secret sharing and split measurement of ABE encryption,the scheme could greatly reduce the cost of mobile users in terms of data publish and access management.Theoretical and experimental analysis shows that the contribution can well meet the requirements of mobile cloud in terms of security,computational complexity and communication cost,which means that it is promising for future applications.     

移动互联网时代“Web前端开发”课程教学模式探究

随着社会科技的不断发展,移动互联网成为各种行业展开工作的全新媒介,同时其自身也是一个具有宽阔就业前景的媒介,Web前端开发便是其中的一种。移动设备的普及以及便利的网络为"Web前端开发"课程教学提供了新的平台。文章就移动互利网背景下该课程的教学特点和存在的问题,对未来的发展提出一定的措施及展望。     

Quality of Service in Mobile and Wireless Networks: The Need for Proactive and Adaptive Applications

Although there are already many fixed networked computers around the world, we will see several orders of magnitude more wireless and mobile devices connected to the Internet. Each car, truck, aircraft, but also many people will carry a plethora of different devices for communication. However, all mobile and wireless systems have in common that the quality of their connectivity may change rapidly over time. Still, users want to get the best quality possible or the quality they pay for respectively. In this paper we describe the implementation of adaptive and proactive applications that are supported by our architecture. The user can express his or her preference by simply clicking on a Q(uality)-button; the process of adaptation is performed without any user interaction. Feedback loops connecting applications, operating system, and network system realize the adaptation. We show how our architecture supports traditional adaptive applications and demonstrate the benefits of proactive applications in wireless and mobile environments.     

Simultaneous image classification and annotation based on probabilistic model

The paper proposes a novel probabilistic generative model for simultaneous image classification and annotation.The model considers the fact that the category information can provide valuable information for image annotation.Once the category of an image is ascertained,the scope of annotation words can be narrowed,and the probability of generating irrelevant annotation words can be reduced.To this end,the idea that annotates images according to class is introduced in the model.Using variational methods,the approximate inference and parameters estimation algorithms of the model are derived,and efficient approximations for classifying and annotating new images are also given.The power of our model is demonstrated on two real world datasets:a 1 600-images LabelMe dataset and a 1 791-images UIUC-Sport dataset.The experiment results show that the classification performance is on par with several state-of-the-art classification models,while the annotation performance is better than that of several state-of-the-art annotation models.     

Design and Performance Studies of an Adaptive Scheme for Serving Dynamic Web Content in a Mobile Computing Environment

Currently, people gain easy access to an increasingly diverse range of mobile devices such as personal digital assistants (PDAs), smart phones, and handheld computers. As dynamic content has become dominant on the fast-growing World Wide Web (C. Yuan et al., 2003), it is necessary to provide effective ways for the users to access such prevalent Web content in a mobile computing environment. During a course of browsing dynamic content on mobile devices, the requested content is first dynamically generated by remote Web server, then transmitted over a wireless network, and, finally, adapted for display' on small screens. This leads to considerable latency and processing load on mobile devices. By integrating a novel Web content adaptation algorithm and an enhanced caching strategy, we propose an adaptive scheme called MobiDNA for serving dynamic content in a mobile computing environment. To validate the feasibility and effectiveness of the proposed MobiDNA system, we construct an experimental testbed to investigate its performance. Experimental results demonstrate that this scheme can effectively improve mobile dynamic content browsing, by improving Web content readability on small displays, decreasing mobile browsing latency, and reducing wireless bandwidth consumption     

Scalable user-friendly image sharing

Image sharing addresses a fault-tolerant protection mechanism for important images. In a typical image sharing scheme, the generated shadow images usually have a noise-like appearance that conceals the secret image completely, but this makes them difficult to identify and manage. This paper proposes a scalable user-friendly image sharing scheme in which each generated shadow image looks like a shrunken replica of the original image. The scheme provides an easy-to-identify interface for managing the shadow images. Compared with previous user-friendly image sharing schemes, the proposed method can reconstruct the original image without any loss and still has the small-size shadow images. A notable feature is that the qualities of generated shadow images are scalable in the proposed scheme, which allows the quality of the shadow images to be adjusted according to the requirements of diverse applications.     

Low-light image enhancement by diffusion pyramid with residuals

With the advancement of the camera-related technology in mobile devices, the vast amount of photos have been taken and shared in our daily life. However, many users still have unsatisfactory experiences with low-visible photos, which are frequently acquired under complicated real-world environments. In this paper, a novel yet simple method for low-light image enhancement has been proposed without any learning procedure. The key idea of the proposed method is to estimate properties of the scene illumination both in global and local manner by exploiting the diffusion pyramid with residuals. Specifically, the residual of each scale level in the diffusion pyramid is combined with the corresponding input. This restored result efficiently highlights local details across different scale spaces, thus it is helpful for preserving the boundary of illuminations. By conducting max-pooling with restored results from different levels of the diffusion pyramid, which are resized to the original resolution, the illumination component is accurately inferred from a given image. Compared to recent learning-based approaches, one important advantage of the proposed method is to effectively avoid the overfitting problem to the specific training dataset. Experimental results on various benchmark datasets demonstrate the efficiency and robustness of the proposed method for low-light image enhancement in real-world scenarios.     

Categorizing images in Web documents

The Web provides an increasingly powerful and popular publication mechanism. Web documents often contain a large number of images that serve various purposes. Identifying the functional categories of these images is an important task in Web repurposing. This article describes a study on the functional categorization of Web images using data collected from news Web sites. As the popularity of the Web soars, the content on the Web is increasingly accessed from wireless devices that have small screens and different bandwidths. Because many Web documents contain a large number of images serving different purposes, how to identify the function of each image so that it can be handled accordingly is an important issue in Web content repurposing. Much work remains to be done in function-based image classification of all images. Icons that appear regularly on Web sites (for example, newspaper logos) could be classified by analyzing different editions of the pages for repetitions. For the host class, a combination of detecting repetitive images and face recognition should help significantly.