With the development of Internet technology, secure storage and secure sharing of data have become increasingly important. Traditional data sharing schemes exist a series of problems including lack of security and low efficiency. In this paper, we construct a secure and efficient data sharing scheme based on threshold Paillier algorithm and blockchain technology, which achieves secure data storage and sharing without a third-party institution. Firstly, we propose a (t,l) threshold Paillier blockchain data sharing scheme, which effectively prevents decryption failures caused by the loss of a single node’s private key. Secondly, we propose a combined on-chain and off-chain data storage scheme, we store the ciphertext on the cloud server and the ciphertext hash value on the blockchain, which not only ensures the integrity of the data but also solves the storage limitation problem on the blockchain. Finally, we use the simulation paradigm to prove the security of the scheme in the semi-honest model. The discussion results of the comparison and the analysis of performance show that the blockchain data security sharing scheme proposed in this paper has lower computational overhead and higher security than other similar schemes.

Over recent decades, rapid urbanization has made people further detached from nature. Researchers from a wide range of disciplines have demonstrated that the growing separateness from nature has adverse impacts on public health and environmental sustainability. Therefore, promoting nature connectedness has been viewed as a prominent and necessary aspiration. Since more and more people live in cities and spend most of their time indoors, urban landscapes and citizens' living environments play an increasingly important role in reconnecting to nature. Under these circumstances, the project aims to use design and technology to gently intervene in people's perceptive and behavioral transformations by encouraging them to notice, value, and have more contact with the nearby nature, as well as deliver nature's restorative effects. A prototype was developed after a cultural probes study, connecting the natural environment with the home space, the digital device with the tangible interaction, the real-life behaviors with the virtual effects.

BACKGROUND: The Raffinose synthetase (RAFS) genes superfamily is critical for the synthesis of raffinose, which accumulates in plant leaves under abiotic stress. However, it remains unclear whether RAFS contributes to resistance to abiotic stress in plants, specifically in the Gossypium species. RESULTS: In this study, we identified 74 RAFS genes from G. hirsutum, G. barbadense, G. arboreum and G. raimondii by using a series of bioinformatic methods. Phylogenetic analysis showed that the RAFS gene family in the four Gossypium species could be divided into four major clades; the relatively uniform distribution of the gene number in each species ranged from 12 to 25 based on species ploidy, most likely resulting from an ancient whole-genome polyploidization. Gene motif analysis showed that the RAFS gene structure was relatively conservative. Promoter analysis for cis-regulatory elements showed that some RAFS genes might be regulated by gibberellins and abscisic acid, which might influence their expression levels. Moreover, we further examined the functions of RAFS under cold, heat, salt and drought stress conditions, based on the expression profile and co-expression network of RAFS genes in Gossypium species. Transcriptome analysis suggested that RAFS genes in clade III are highly expressed in organs such as seed, root, cotyledon, ovule and fiber, and under abiotic stress in particular, indicating the involvement of genes belonging to clade III in resistance to abiotic stress. Gene co-expressed network analysis showed that GhRFS2A-GhRFS6A, GhRFS6D, GhRFS7D and GhRFS8A-GhRFS11A were key genes, with high expression levels under salt, drought, cold and heat stress. CONCLUSION: The findings may provide insights into the evolutionary relationships and expression patterns of RAFS genes in Gossypium species and a theoretical basis for the identification of stress resistance materials in cotton.

Digital garage maps are the basis for future vehicle navigation services such as smart parking management that displays the availability of parking spaces. It can direct drivers to empty ones, avoiding any searching, circulating in large, complex parking structures. However, such maps are not currently available, making it impossible to deploy smart parking management. Conducting manual survey incurs tremendous amount of human efforts, and cannot scale to large numbers of garages. In this paper, we propose three algorithms, Sequential Merging, Points Clustering and Segments Matching that can automatically construct complete and accurate garage maps using data crowdsensed from drivers. Upon entering and leaving the garage, the driver's smartphone collects inertial data, which are used to generate the vehicle's trajectory. Our algorithms fuse together these trajectories to recreate the size, layout of the garage. We compare the performance of the three algorithms using different garages. We find that Points Clustering is robust to trajectory errors, with F-score above 0.95 for trajectory length error up to 2 meters, Segments Matching can handle partial trajectories with arbitrary start/end locations, and it constructs the same map using trajectories much shorter than those needed by the other two algorithms.

With the growing popularity of multi-core technology, traditional MPI programs are facing great challenges in fully exploit the computing power of this kind of chipsets. In this paper, we change the run time orgnaization of a MPI program and use some newly designed communication methods to enhance the performance of MPI programs on a multicore system without changing the code. We have evaluated the test results and the potential "side effects'' of this technique is discussed in the paper as well. The remarks on the related and possible future research work is also given in the end of the paper.

Soft hang is an action that was expected to respond instantly but instead drives an application into a coma. While the application usually responds eventually, users cannot issue other requests while waiting. Such hang problems are widespread in productivity tools such as desktop applications; similar issues arise in server programs as well. Hang problems arise because the software contains blocking or time-consuming operations in graphical user interface (GUI) and other time-critical call paths that should not.

Region-based memory management is a popular scheme in systems software for better organization and performance. In the scheme, a developer constructs a hierarchy of regions of different lifetimes and allocates objects in regions. When the developer deletes a region, the runtime will recursively delete all its subregions and simultaneously reclaim objects in the regions. The developer must construct a consistent placement of objects in regions; otherwise, if a region that contains pointers to other regions is not always deleted before pointees, an inconsistency will surface and cause dangling pointers, which may lead to either crashes or leaks.

Virtual Interface Architecture (VIA) established a communication model with low latency and high bandwidth, and defined the standard of user-level high-performance communication specification in cluster systems. This paper analyzes the current development, principle and implementations of VIA, and presents user-level high-performance communication software, MyVIA, based on Myrinet, which is comfortable with VIA specification. The paper first describes the design principle and framework of MyVIA, then proposes new technologies of MyVIA including User TLB, continued host physical memory and varied NIC buffer, the pipelining communication based on resource and DMA chain, and physical descriptor ring. Experimental results of performance comparisons and analysis are presented; the one-way bandwidth of MyVIA for a 4 KB message is 250 MB/s, and the lowest one-way latency is 8.46 /spl mu/s, which shows that the performance of MyVIA surpassed that of other implementations of VIA.