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Autonomous underwater gliders are robotic underwater vehicles that do not require operator input. They are frequently deployed in large-scale, long-term ocean-sampling missions that take advantage of their buoyancy-driven engines and very low power consumption. A limitation of the buoyancy-driven engine design is that the glider must travel at slow speeds and is unable to confront strong upstream currents. Optimal path-planning to minimize the upstream-current effect and distance traversed is helpful to guide the glider navigating in the ocean. In a glider path-planning problem, reachability signifies that a minimal upstream-current effect along a path is achieved, while efficiency refers to optimizing path distance, to make it as short as possible. Reachability and efficiency are sometimes inconsistent goals in glider path-planning, and obtaining an optimal solution between both aspects of path-planning constitutes a multi-objective optimization problem. In order to discover an optimal path for glider safety, a parallel genetic approach to the glider path-planning is developed here. We present a novel scheme of upstream-current avoidance to solve the critical path-planning problem in deployment of multiple gliders. The benefits of the proposed approach are used to produce characteristic curves that express how improved cruising capability benefits path diversity. The reachability of an important scheme of upstream-current avoidance is validated by a maximum likelihood function. Moreover, a new crossover operator is proposed to encourage individuals of offspring in solution diversity. Numeric results demonstrate that the proposed path-planning approach determines an optimal path that reduces the upstream-current effect, and also shortens the cruising distance in multi-glider path-planning solutions.

Three types of petroleum-based tricycloalkyl-containing methacrylate polymers derived from adamantane and DCPD were synthesized and characterized, poly(1-adamantyl methacrylate) (PADMA), poly(tricyclodecyl methacrylate) (PTCDMA) and poly(1-adamantyl methacrylate-co-tricyclodecyl methacrylate) (P(ADMA-co-TCDMA)). As expected, the incorporation of a tricycloalkyl substituent as a pendant group on the methacrylate polymer contributed to enhancement of thermal stability in combination with high transparency in the UV–vis region and long-term thermal resistance, in addition to improved mechanical properties, a lower CTE, decreased water absorption and a lower dielectric constant. These merits make tricycloalkyl-containing methacrylate polymers promising candidates for use as high value-added optical plastics in the microelectronics and optoelectronics applications.

Whether surveying the lake, river, or ocean, side-scan sonar system is one of the vital instruments in marine science that maps the seafloor for discoveries of shipwrecks, underwater archaeology, and submerged structures; or represents the water column backscattering for researches of marine biology and seagrass measurement. In operation of side-scan sonar survey, determining the altitude of transducer head is critical to avoid collisions between the transducer head and the seabed. On the other hand, determining the altitude of transducer head is namely a technology of bottom tracking. Usually, the bottom tracking inside the sonar software receives the first return acoustic signals from the seabed and computes the depth of the seabed below the transducer head, not from the surface. Moreover, sometimes the first return signals reflected by halobios or ship wake flow caused by propeller churning interferes the result of bottom tracking and determines the wrong altitude of transducer head on the waterfall display. In this paper, an overview of state-of-the-art side-scan sonar bottom tracking technologies is discussed in advance. Afterwards, an adaptive bottom tracking algorithm is introduced to construct a bottom tracking for seabed mapping by means of integrated image processing technologies. Finally, the results show that the adaptive bottom tracking algorithm provides good accuracy of seabed mapping in various geomorphological features.

In this work, an exponential effective function (EEF) is developed as fitness function applied in a hybrid-Genetic Algorithm (hybrid-GA) to propose a genetic-based effective approach to the glider path-planning of ocean-sampling mission in variable oceans. The proposed EEF is such an objective function that is able to be implemented in optimization algorithm such as Genetic Algorithm (GA) for evaluation of the fittest path. In consideration of the glider path-planning problem (GPP), two motivations are driven by the proposed approach to the glider path-planning in discovery of: (1) a reachable path with the upstream-current avoidance (UCA) in variable oceans; (2) an efficient path for the glider ocean-sampling mission. The exponential combination of the glider motion and current effects as well as the cruising distance benefits the path in terms of reachability and efficiency. The reachability is the first motivation to discover a reachable path implemented by the scheme of UCA, while the efficiency is the second motivation to shorten the cruising distance. Meanwhile, the stabilized path solution is accomplished by hybrid-GA. In variable oceans, currents severely impact the path solution and lead the global optimum to absence. Therefore, alternative is to discover an optimal path with the minimum upstream-current sub-paths to approximate the minimal cruising distance in the condition that the discovered cruising distance should be less than the glider cruising range. To deeply analyze the path reachability, two theorems are developed to verify the conditions of the downstream-current angle (DCA). To evaluate the path-planning performances, 6 state-of-the-art fitness functions are studied and used to make a fair comparison with the EEF in hybrid-GA. First of all, 112 scenarios are created in the restricted random current variations (RRCV). Secondly, 21 scenarios are created in the near-real Kuroshio Current of east Taiwan (KCET) introducing from an ocean prediction model. These scenarios are designed to evaluate fairly the EEF in hybrid-GA. Numeric results show that whether the RRCV or the KCET, the proposed EEF indeed is able to discover the optimal path with the benefits of reachability and efficiency. Therefore, the proposed genetic-based effective approach is well developed to solve the GPP in variable oceans.

This paper sampled approximately 9.3 million entries of data, concerning payments from 300,000 credit card customers over the past two years of Bank A in Taiwan. By applying data mining techniques to decipher customers' behavior and perform risk analysis, the clustering algorithms divides card users into 9 groups of different levels of contributions and risk profiles, according to their consumption patterns. We generalize a set of clustering rules to identify high risk customer groups in advance. Therefore, the proposed suggestions could tell who was a bad risk and either deny their application or, for those who were already cardholders, start shrinking their available credit and increasing minimum payments to squeeze out as much cash as possible before they defaulted. On the other hand, banks are advised to adjust credit limits in a timely manner for the customer groups whose risks are low and contributions are high, in addition to the provision of value added services, in order to enhance earnings.

Traditional assessment tools, such as ''Learning and Study Strategy Scale Inventory (LASSI)'', are typically pen-and-paper tests that require responses to a multitude of questions. This may easily lead to student's resistance, fatigue and unwillingness to complete the assessment. To improve the situation, a hybrid data mining technique was applied to analyze the LASSI surveys of freshmen students at Tamkang University. The most significant contribution of this research is in dynamically reducing the number of questions while the LASSI assessment is proceeding. To verify the appliance of the proposed method, a web-based LASSI self-assessment system (Web-LSA) was developed. This system can be used as a guide to determine study disturbances for high-risk groups, and can provide counselors with fundamental information on which to base follow-up counseling services to its users.

An amphiphilic colloidal copolymer containing methyl methacrylate (MMA) and sodium acrylate at different compositions was prepared by a free-emulsion polymerization method with potassium persulfate as an initiator, and it was then doped in HCl solution to obtain the acid form poly(methyl methacrylate-co-acrylic acid) (PMMAA) copolymer. The copolymers were characterized by means of gel permeation chromatography, 1H nuclear magnetic resonance spectrometer, 13C solid-state nuclear magnetic resonance spectrometer, infrared spectra, and differential scanning calorimeter. The copolymers have only a single, and nearly constant, glass transition temperature of 124°C, at which there is no observable effect on the structure of the copolymer. The monomer reactivity ratios rNaAA and rMMA were rNaAA = 1.06, rMMA = 0.70 and rNaAA = 1.02, and rMMA = 0.63 estimated respectively by using the classical Fineman-Ross and the Kelen-Tudos methods. The results revealed that the copolymer had a tendency towards the formation of small acrylic acid blocks that have very short segments of MMA. The proton spin-lattice relaxation time in the rotating frame T indicated single composition-dependent for all copolymers, which imply dynamic homogeneity and a good miscibility with chain dynamics on the upper spatial scale of 3 nm existed in the PMMAA copolymer. An increase of the thermal stability of the copolymers was shown from the apparent activation energy of the thermal degradation process for the copolymers relative to the homopolymers. POLYM. COMPOS., 29:37–44, 2008. © 2007 Society of Plastics Engineers

Although several researchers have used statistical methods to prove that aspiration followed by the injection of 95% ethanol left in situ (retention) is an effective treatment for ovarian endometriomas, very few discuss the different conditions that could generate different recovery rates for the patients. Therefore, this study adopts the statistical method and decision tree techniques together to analyze the postoperative status of ovarian endometriosis patients under different conditions. Since our collected data set is small, containing only 212 records, we use all of these data as the training data. Therefore, instead of using a resultant tree to generate rules directly, we use the value of each node as a cut point to generate all possible rules from the tree first. Then, using t -test, we verify the rules to discover some useful description rules after all possible rules from the tree have been generated. Experimental results show that our approach can find some new interesting knowledge about recurrent ovarian endometriomas under different conditions.

Traditional learning activity has inherently restricted by time and space. New learning paradigms, such as M-learning becomes an irreplaceable learning tool because learner is not confined in the restricted environment. Such a new learning system benefits students in cases of lifelong learners and new influenza. Moreover, several new wireless communication technologies are developed and deployed for marketing needs. For examples, mobile cellular network such as WCDMA, WiMAX and LTE; and WLAN such as IEEE 802.11b/g/n. These technologies are formed different access networks and used to connect to internet easily anytime and anywhere with any available portable devices such as PDA, laptop, netbook and smart phone. Meanwhile, several emerging applications are applied in M-Learning such as Short Message Service, Multimedia Messaging Service, Location Based Service and broadcasting service such as IPTV. IPTV is a broadcasting TV service based on Internet Protocol. Traditional TV services are very popular in house, school or company. But it is a one-direction TV service without interaction. The IPTV services possess a main feature of bi-direction connection that can provide interactive TV services such as voting service, TV shopping and interactive instruction. Personal Video Recorder (PVR) is one of important IPTV services. PVR stores video content from broadcast TV and replays it at any convenient time. The IPTV PVR service can be used to product interactive multimedia teaching materials. Therefore, this study proposes a framework of novel learning environment: A scaffolding M-learning framework with IMS based IPTV PVR service. In this framework based on IMS, access networks which supported by IMS can be integrated into core IMS network and then services can be inter-operated between different access networks. With an adaptive scaffold, learners study independently, handle any situation they encounter, increase learning efficiency and achieve seamless learning space. Furthermore, teacher's precious knowledge and experiences are gathered, preserved and passed down completely.

An adaptive ecology m-learning framework applied for national parks is proposed in this paper. The traditional ecology guiding service uses static web page or fixed placard to prompt and provide ecology information to learners. It can not provide adaptive learning anytime and anywhere. Learners can not obtain real-time ecology guiding information and have a good adaptive learning based on learners' knowledge background, and time and location. This study proposes a framework based on Scaffolding Theory that provide learners mobile, dynamic and adaptive ecology guiding service to national parks. Scaffolding Theory is to support learners a knowledge structure for systematic learning. Based on Scaffolding Theory, learners are identified by background (e.g. age and gender), knowledge (e.g. cognitive base, knowledge requirement and learning objective), and interests. Moreover, adaptive and appropriate ecology knowledge based on learners' properties is provided dynamically. Furthermore, learning steps and contents are able to be adjusted flexibly by learners' feedback. In addition, this study also adopt context awareness to provide the learner a suitable route planning for ecology guiding service according to environment factors such as weather condition, time and season, prediction of tide, UV rays and rain rate where learners located. Landscapes and ecology events such as Migratory birds in transit within the route can be actively delivered to learners immediately using interactive applications such as multimedia messages (e.g. text, image and video). Attention and enjoyment of learners can be increased and ecology education purpose of national parks can be achieved.

A Temperature Surveillance System (TSS) developed on technologies of wireless sensor networks (WSN) and embedded systems (ES), to monitor the temperatures of residential environments is presented for blaze detection. The space temperature patters captured by a customized WSN is analyzed by an algorithm named as Determination of Temperature Anomalies (DTA) to evaluate the risk of a possible fire alarm. Once the temperature pattern depicts critical conditions, the TSS issues an alarm through SMS on 2G/3G networks to local and remote users. Thus, TSS will benefit the safety of home environments and the saving of people life as well as property. Furthermore, the cost of social security is also improved by the deployment of such a system.

Due to increasing occurrence of accidents and illness during business trips, travel, or overseas studies, the requirement for portable EMR (Electronic Medical Records) has increased. This study proposes integrating streaming media technology into the EMR system to facilitate referrals, contracted laboratories, and disease notification among hospitals. The current study encoded static and dynamic medical images of patients into a streaming video format and stored them in a Flash Media Server (FMS). Based on the Taiwan Electronic Medical Record Template (TMT) standard, EMR records can be converted into XML documents and used to integrate description fields with embedded streaming videos. This investigation implemented a web-based portable EMR interchanging system using streaming media techniques to expedite exchanging medical image information among hospitals. The proposed architecture of the portable EMR retrieval system not only provides local hospital users the ability to acquire EMR text files from a previous hospital, but also helps access static and dynamic medical images as reference for clinical diagnosis and treatment. The proposed method protects property rights of medical images through information security mechanisms of the Medical Record Interchange Service Center and Health Certificate Authorization to facilitate proper, efficient, and continuous treatment of patients.

The capability of providing real-time multimedia player over the Internet is an important future application for embedded system. However, the main challenge of such an application is the limitation on computation performance and memory size in architecture of embedded system, especially while encoding and decoding. In this paper, a streaming packet tracer (SPT) algorithm is proposed for realtime tracing the streaming packet header. Based on the SPT algorithm, we present a novel software-based technique which enables a non-DSP embedded system to play and record real-time streaming audio simultaneously. To verify the feasibility of the proposed technique, a real-time Internet radio recorder has been implemented on SBC-2410x embedded system successfully. The experimental results show that our achievement has reduced the CPU usage rate from over 100% to about 30%-40% in comparison with other recording method.