Win-Tsung Lo

Adaptive scheduling for parallel tasks with QoS satisfaction for hybrid cloud environments

A hybrid cloud integrates private clouds and public clouds into one unified environment. For the economy and the efficiency reasons, the hybrid cloud environment should be able to automatically maximize the utilization rate of the private cloud and minimize the cost of the public cloud when users submit their computing jobs to the environment. In this paper, we propose the Adaptive-Scheduling-with-QoS-Satisfaction algorithm, namely AsQ, for the hybrid cloud environment to raise the resource utilization rate of the private cloud and to diminish task response time as much as possible. We exploit runtime estimation and several fast scheduling strategies for near-optimal resource allocation, which results in high resource utilization rate and low execution time in the private cloud. Moreover, the near-optimal allocation in the private cloud can reduce the amount of tasks that need to be executed on the public cloud to satisfy their deadline. For the tasks that have to be dispatched to the public cloud, we choose the minimal cost strategy to reduce the cost of using public clouds based on the characteristics of tasks such as workload size and data size. Therefore, the AsQ can achieve a total optimization regarding cost and deadline constraints. Many experiments have been conducted to evaluate the performance of the proposed AsQ. The results show that the performance of the proposed AsQ is superior to recent similar algorithms in terms of task waiting time, task execution time and task finish time. The results also show that the proposed algorithm achieves a better QoS satisfaction rate than other similar studies.

Mobile cloud-based depression diagnosis using an ontology and a Bayesian network

Recently, depression has becomes a widespread disease throughout the world. However, most people are not aware of the possibility of becoming depressed during their daily lives. Therefore, obtaining an accurate diagnosis of depression is an important issue in healthcare. In this study, we built an inference model based on an ontology and a Bayesian network to infer the possibility of becoming depressed, and we implemented a prototype using a mobile agent platform as a proof-of-concept in the mobile cloud. We developed an ontology model based on the terminology used to describe depression and we utilized a Bayesian network to infer the probability of becoming depressed. We also implemented the system using multi-agents to run on the Android platform, thereby demonstrating the feasibility of this method, and we addressed various implementation issues. The results showed that our method may be useful for inferring a diagnosis of depression. Integrating Ontology with Bayesian Network to predict getting depressed or not.Using mobile agent and cloud environment to implement the diagnosis environment.Evaluation result shown the system is feasibility for doing the prediction.

CUDT: A CUDA Based Decision Tree Algorithm

Decision tree is one of the famous classification methods in data mining. Many researches have been proposed, which were focusing on improving the performance of decision tree. However, those algorithms are developed and run on traditional distributed systems. Obviously the latency could not be improved while processing huge data generated by ubiquitous sensing node in the era without new technology help. In order to improve data processing latency in huge data mining, in this paper, we design and implement a new parallelized decision tree algorithm on a CUDA (compute unified device architecture), which is a GPGPU solution provided by NVIDIA. In the proposed system, CPU is responsible for flow control while the GPU is responsible for computation. We have conducted many experiments to evaluate system performance of CUDT and made a comparison with traditional CPU version. The results show that CUDT is 5∼55 times faster than Weka-j48 and is 18 times speedup than SPRINT for large data set.

A new architecture for integration of CORBA and OODB

Object oriented database system (OODB) supports an object oriented data model with the functionality of persistency and transaction semantics. In order to facilitate the use of OODB, the Object Database Management Group (ODMG) defined a standard for object database management systems. On the other hand, the Object Management Group (OMG) defined the Common Object Request Broker Architecture (CORBA), which is an emerging standard of distributed object technology providing the interconnection network between distributed objects. For the sake of matching these two object models, taking the advantages of merging both of them, and building a more sophisticated infrastructure, the integration of CORBA and OODB is currently an urgent and important issue in distributed object systems. Instead of using Object Database Adapter (ODA) suggested by the ODMG, we provide a novel way of reusing the Object Transaction Service (OTS) and wrapping techniques to introduce OODB into CORBA automatically. Through our design, CORBA clients or OODB object implementers do not need to learn any knowledge of each other. In addition, error recovery is also provided to guarantee the consistency of object states. The whole task for integrating CORBA and OODB is done transparently by our proposed preprocessor, which plays an important role in solving problems encountered by ORB and OODB vendors easily.

A Generic Application Sharing Architecture Based on Message-Oriented Middleware Platform

Previous application sharing systems have no unified communication protocols. The well known application sharing protocols include RFB (Remote FrameBuffer), RDP (Remote Desktop Protocol) and ITU-T T.128. A generic application sharing architecture is proposed for providing the capability of connecting various application sharing servers with the same application sharing client. A communication standard for application sharing systems is defined based on the Message-Oriented Middleware (MOM). To compare with previous application sharing systems, there are many advantages including easy to use, easy to connect, easy to integrate, higher scalability and less bandwidth consumption.

A fault tolerant object transaction service in CORBA

The concept of transactions is not only indispensable in database applications, but also useful in building robust software for mission critical applications. The paper presents an implementation of the Object Transaction Service (OTS) based on CORBA 2.0 specification. Transactional applications developed with the support of our OTS implementation are able to assure the ACID properties even in the presence of node crashes, software system failures and process hangs. The preliminary results obtained from the experiments on Sun workstations with Orbix 1.3 show that the overhead due to the OTS service is satisfactory for most applications.

Design and Implementation of File Deduplication Framework on HDFS

File systems are designed to control how files are stored and retrieved. Without knowing the context and semantics of file contents, file systems often contain duplicate copies and result in redundant consumptions of storage space and network bandwidth. It has been a complex and challenging issue for enterprises to seek deduplication technologies to reduce cost and increase the storage efficiency. To solve such problem, researchers proposed in-line or offline solutions for primary storages or backup systems at the subfile or whole-file level. Some of the technologies are used for file servers and database systems. Fewer studies focus on the cloud file system deduplication technologies at the application level, especially for the Hadoop distributed file system. It is the goal of this paper to design a file deduplication framework on Hadoop distributed file system for cloud application developers. The architecture, interface, and implementation experiences are also shared in this paper.

MEDEA-a model for the event-based data exchange architecture

Traditional data interchange mechanisms are based on the client-server model, which has been confronted with a plethora of problems. For example, bilateral partners must exchange data sets through recognized protocols. Whenever the data set is updated, data interchange participants have to rebuild their protocols as well as applications. It is really a considerable problem for system maintenance or scalability. We propose an event-based data exchange model, called MEDEA, to solve the problems encountered by traditional data exchange systems. The designed MEDEA data exchange framework and the learned experiences are also detailed.

A generic application sharing architecture based on message-oriented middleware platform

Previous application sharing systems have no unified communication protocols. The well known application sharing protocols include RFB (remote framebuffer), RDP (remote desktop protocol) and ITU-T T.128. A generic application sharing architecture is proposed for providing the capability of connecting various application sharing servers with the same application sharing client. A communication standard for application sharing systems is defined based on the message-oriented middleware (MOM). To compare with previous application sharing systems, there are many advantages including easy to use, easy to connect, easy to integrate, higher scalability and less bandwidth consumption

Object finding system based on RFID technology

Locations of moving or missing objects are getting important information for context-aware applications which try to get the locality of an object, and then provide services pertaining to the object. To position an object, most systems use a predefined coordinate to compute object location while sensing the appearance of the target object. Usually, it is troublesome and costs much to define the base coordinate in advance for most object positioning systems, especially when the target object is locating in an unknown environment. To reduce the cost and complexity of object locating system and improve the accuracy of location, this paper proposed an Object Finding System based on RFID technology to identify the localities of target objects in buildings. In this paper, we introduce the design concepts of the proposed system as well as the algorithms used to calculate the object locations. In addition, the experimental results show that it is a feasibility study.