Systems In Mobile Environment Research Articles

Research on the system and method of online learning provided by mobile learning environment

In recent years, with the rapid development and progress of information technology, education department management personnel in order to effectively improve the effect of online learning, through the setting of mobile environment teaching mode, along with the online learning system to improve the update, attracted wide attention in the education circle. This paper mainly analyzes and researches the automatic evaluation method of learning system in mobile environment.

Design and implementation for semantic information retrieval through convergence of ontology and user context based on mobile device

On account of prevalence of mobile devices, a variety of mobile-based services have been conducted recently. In this situation, it is possible to serve the information that fits to users’ requests according to the users’ context using mobile devices. Therefore, it is necessary to research data mining techniques with mobile devices. Therefore, we researched information retrieval system in mobile environment. We applied semantic data mining method with context information ontology. These techniques of semantic information retrieval can provide the information according to users’ context information such as location, weather, user preference etc. exactly and rapidly anytime and anyplace. In modern society, it is essential to develop mobile information retrieval system which is efficient to users. Also, the system can provide users’ current location and the location information with Google map APIs in mobile devices. Therefore, in this paper, we researched semantic data mining technique with context information ontology using mobile techniques. And we compared and evaluated our proposed model and the existing model in three areas and showed our proposed model has higher performance.

Undesired Radiation Suppression Technique with Adaptive Control for Distributed Array Antenna Systems in Mobile Environment

We have proposed a distributed array antenna (DAA) system for high-speed satellite communications. The DAA system uses multiple small tracking antennas and combines the transmission signals in-phase to increase the antenna gain. DAA system has a problem that the undesired radiation at the sidelobe direction increases as the antenna gain at the main lobe direction increases. In the mobile environment, the conventional technique can suppress the undesired radiation in the limited condition because of changing the direction of the undesired radiation according to the movement of the mobile station. This paper proposes a DAA technique that suppresses the undesired radiation by setting a transmission plate at each antenna aperture and moving them via adaptive control. The transmission plate consisting of a metal patch or slot retransmits electromagnetic waves and changes the amplitude and phase of the waves. To change the radiation patters of each antenna, the transmission plate rotates according to movement of the mobile station. After combining these changed signals, the adaptive control selects the rotate angle of the transmission plate to decrease the undesired radiation at the sidelobe direction. The antenna gain on the main lobe direction after combining is achieved with lower loss because the insertion loss through the transmission plate is smaller. The proposed technique offers more than $2.4$ dB improvement with three antennas and more than $3.5$ dB improvement with four antennas assuming each consists of $8 ¥times 8$ patches.

A Comparison Between AHP and Hybrid AHP for Mobile Based Culinary Recommendation System

Mobile based culinary recommendation system has become critical topic in mobile application. Some methods presented in the literature propose the use of the AHP (Analytic Hierarchy Process), AHP TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) and fuzzy AHP for mobile based culinary recommendation system. However, there are no comparative studies of these three methods when applied to mobile based culinary recommendation system. Thus, this research presents a comparative analysis of these three methods in the context of culinary recommendation system in mobile environment. The comparison was made based on accuracy and time complexity because mobile application environment needs low time complexity. The results have shown that all of these methods are suitable for culinary recommendation system in mobile environment. Fuzzy AHP have the highest accuracy between all of these methods, it have 66,67 % accuracy. But, AHP TOPSIS shows the best performance in time complexity, with order of growth in quadratic class (n2)

Context-aware recommender systems in mobile environment: On the road of future research

Recommender systems have recently been singled out as a fascinating area of research, owing to the technological progress in mobile devices, such as smartphones and tablets, as well as to the rapid growth of social networking. In this respect, the main purpose of recommender systems is to suggest items that help users to make decisions from a large number of possible actions such as what place to visit, what movie to watch, or which friend to add to a social network system. In mobile environment, many personal, social and environmental contextual factors can be integrated into the recommendation process in order to provide the correct recommendation to a special user, at the perfect moment, in the appropriate location based on his/her emotional state, his/her current activity and past behavior. This paper provides an overview of context-aware recommender systems in mobile environment. The objective of this systematic review is to investigate the current state of the art in context-aware recommender systems and classify the reviewed research papers. This study aims equally to identify the possible future directions in this research area.

An Adaptive Web-based Framework for Mobile Telemonitoring System

Mobile long distance monitoring system using web-based will be deliberated as one of the primary industry in the near future. This paper focuses on the development of the healthcare service for telemonitoring system using an adaptive web-based framework with several parameters at the same time. The proposed system is used to make easy the patient and physician for accessing healthcare system. It tries to combine many functions in healthcare services for long distance monitoring system. Physiological parameters are used such as blood pressure, blood sugar, respiration, heartbeat, pulse, temperature will be received by the system then it is sent to the clinic server immediately. All of these parameters can be inputted by patients themselves while the patients are far from the clinical environment and forward to the physician for further diagnosis and medical treatment. The advantages of the proposed system are the patient will be easy to access the system through internet and easy to connect the physician from a remote area. Smartphone with multimedia features and internet connection in mobile environment can be used to perform mobile computing anywhere and anytime. It keeps real-time recording and monitoring of physiology parameters of the patients at lowest cost and at home. The physiology parameters of patient are increased to be multimedia data. By using the good quality of the multimedia data, the physician will be more precise to perform diagnosis and medical treatment to the patient. The proposed framework can be used to develop a practical web-based mobile telemonitoring system in mobile environment.

Implementation of semantic information retrieval system in mobile environment

Implementation of semantic information retrieval system in mobile environment

Speech Recognition using Hidden Markov Models in Embedded Platform

Speech recognition used widely in environment of mobile application. The Study of speech recognition is one of the main topics of journal in artificial intelligence which doesn’t take out meaningful result. The reason of such result is to relate with difficulty of feature extraction. Liner Predictive Coding, Hidden Markov Model, Artificial Neural Network are known to be effective in the same way as for the voice signal processing. Mel frequency cepstral coefficients are the most popular method for extracting speech features from the speech recognition field. This paper proposes a method for recognizing speech using Mel-frequency information. In this paper we propose Automatic Speech Recognition (ASR) technique using Mel-Frequency Cepstral Coefficient extraction and Hidden Markov Model in mobile environment. Our method is used to speech enhancement technique. We’ll try to implement ASR system in mobile environment using embedded platform.

시간 영역 시퀀스 패턴에 기반한 한국어 모음 'ㅐ'의 음성 인식

As computing and network technologies are further developed, communication equipment continues to become smaller, and as a result, mobility is now a predominant feature of current technology. Therefore, demand for speech recognition systems in mobile environments is rapidly increasing. This paper proposes a novel method to recognize the Korean vowel 'ㅐ' as a part of a phoneme-based Korean speech recognition system. The proposed method works by analyzing a sequence of patterns in the time domain instead of the frequency domain, and consequently, its use can markedly reduce computational costs. Three algorithms are presented to detect typical sequence patterns of 'ㅐ', and these are combined to produce the final decision. The results of the experiment show that the proposed method has an accuracy of 89.1% in recognizing the vowel 'ㅐ'.

한국어 음성 인식에서 변동성과 벌크 지표에 기반한 음소 경계 검출

Today, the demand for speech recognition systems in mobile environments is increasing rapidly. This paper proposes a novel method for Korean phoneme segmentation that is applicable to a phoneme based Korean speech recognition system. First, the input signal constitutes blocks of the same size. The proposed method is based on a volatility indicator calculated for each block of the input speech signal, and the bulk indicators calculated for each bulk in blocks, where a bulk is a set of adjacent samples that have the same sign as that of the primitive indicators for phoneme segmentation. The input signal vowels, voiced consonants, and voiceless consonants are sequentially recognized and the boundaries among phonemes are found using three devoted recognition algorithms that combine the two types of primitive indicators. The experimental results show that the proposed method can markedly reduce the error rate of the existing phoneme segmentation method.

Time evolution of face recognition in accessible scenarios

AbstractUp to now, biometric recognition has shown significant advantages as to be considered a reliable solution for security systems in mobile environments. Nevertheless, due to the short lifetime of biometrics in mobile devices, a handful of concerns regarding usability and accessibility need to be covered in order to meet users’ requirements. This work is focused on analysing the usability and accessibility of a face recognition system used by visually impaired people, focusing on the time spent in the process, which is a critical aspect. Specifically, we cover different key questions including which kind of feedback is more useful for visually impaired users and beneficial for performance and how is the performance evolution in contrast with the time spent in the recognition. Our findings suggest that several parameters improve along with the time spent in the process, including performance. The audio feedback provided in real time involves also better performance and user experience than instructions given previously.

An Empirical Study on the Success Factors of Academic Affairs Information System in Mobile Environment

스마트 시대의 도래로 모바일 환경 기반의 학사 정보시스템 도입 및 활용에 대한 관심이 증가하고 있으나, 이에 대한 연구는 부족한 실정이다. 이에 본 연구는 기존의 정보시스템 성공 모델을 기반으로 모바일 환경에서의 학사 정보시스템 성공 모델을 제안하고 이를 실증하고자, 문헌 고찰을 통해 학사 정보시스템의 성공을 지속적 이용으로 규정하고 정보시스템 품질 요인(시스템 품질, 정보 품질, 서비스 품질)과 지각된 유용성, 그리고 이용자 만족도를 성공에 영향을 미치는 변수로 제시하였다. 연구 결과, 시스템 품질을 제외한 정보 품질과 서비스 품질은 지각된 유용성에 영향을 미치고, 정보시스템 품질 요인과 지각된 유용성은 이용자 만족에 유의한 영향을 미치는 것으로 나타났다. 또한 지각된 유용성과 이용자 만족은 지속이용의도에 유의한 영향을 미치는 것으로 나타났다. 본 연구를 통하여 모바일 환경에서의 학사 정보시스템 이용 행동을 이해 할 수 있는 계기를 제공하고, 나아가 고객 충성도 제고를 위한 방향성을 제공했다는 점을 연구적 가치로 말 할 수 있을 것이다.

Using Cellular Automata to Reduce Congestion for Tourist Navigation Systems in Mobile Environments

Tourist navigation systems have become an important area of research because they help people increase the quality of their travel. This work proposes an adaptive recommendation mechanism that relies on a congestion-aware scheduling method for multiple groups of travelers on multi-destination trips. The recommendation scheme uses the cell (number of groups) mechanism of the cellular automata model for group system distribution. To reduce congestion while visiting multiple destinations, we present a tour group with adaptive recommendations from a system to yield a high quality tour experience. When faced with congestion, the system proposes a path by which the group visits a secondary destination first and then visits the primary destination. Simulation results reveal the strengths of the proposed "adaptive recommendation mechanism" model in terms of decreasing the average wait time, congestion, and the ratio of congestion avoidance to the number of groups.

Editorial for Special Issue on “New Technologies and Applications for Wireless Communications & Mobile Cloud Computing”

Editorial: This special issue features eight selected papers with high quality. The first article, “A Cost-Effective Methodology Applied to Videoconference Services on Hybrid Clouds” by Javier Cervino, Pedro Rodriguez, Irena Trajkovska, Fernando Escribano and Joaquin Salvachua, tackles the optimization of applications in multi-provider hybrid cloud scenarios from an economic point of view. However the approach was intended to introduce a novel solution by making maximum use of divide and rule. Also this article describes a methodology to create cost aware cloud applications that can be broken down into the three most important components in cloud infrastructures: computation, network and storage. A real videoconference system has been modified in order to evaluate this idea with both theoretical and empirical experiments. The proposed system has become a widely used as a tool in several national and European projects for e-learning and collaboration purposes. The second article, “An Efficient Dynamic Integration Middleware for Cyber-Physical Systems in Mobile Environments” by Young-Sik Jeong, Sang Oh Park and Jong Hyuk Park, proposes a cyber-physical system (CPS) middleware framework that ensures interoperability and communication between heterogeneous components in a global CPS network. A CPS is a tight integration of the system’s computational and physical elements. The CPS technology builds on the older discipline of embedded systems, and CPS applications can be found in diverse industry sectors, such as smart home, health care, and transportation. The article assume that a global CPS network that integrates different CPS networks appears in the near future. Through local and global communications, the proposed middleware makes mobile devices in different networks interoperable. The third article, “Particle Swarm Optimization with Skyline Operator for Fast Cloud-based Web Service Composition” by Shangguang Wang, Qibo Sun, Hua Zou, Fangchun Yang, proposed a fast Cloud-based web service T. Shon (*) Division of Information and Computer Engineering, College of Information Technology, Ajou University, Suwon, South Korea e-mail: taeshik.shon@gmail.com

An Efficient Dynamic Integration Middleware for Cyber-Physical Systems in Mobile Environments

Advances in information technologies have brought a wide variety of computing environments. In recent years, integrations of computational, networking, and physical elements in different environments tend to increase, so interoperability between heterogeneous computing elements has become a key area of research. A cyber-physical system (CPS) that has gained a lot of attention lately is a tight integration of the system's computational and physical elements. The CPS technology builds on the older discipline of embedded systems, and CPS applications can be found in diverse industry sectors, such as smart home, health care, and transportation. There is a high possibility that a global CPS network that integrates different CPS networks appears in the near future. This paper proposes a CPS middleware framework that ensures interoperability and communication between heterogeneous components in a global CPS network. Through local and global communications, the proposed middleware makes mobile devices in different networks interoperable. It employs Internet Protocol version 6 (IPv6) and performs protocol conversion to communicate with devices using different protocols.

User-selectable interactive recommendation system in mobile environment

Mobile devices need to provide more accurate and personalized information in a computing environment with a small screen and limited information retrieval functions. This paper presents a user-selectable recommendation system that reflects a user interest group by employing collaborative filtering as technique to provide useful information in a mobile environment. We form similar groups by simultaneously considering a user's information preferences and demographics. Then we reconstruct lists of a final recommendation based on what search results the similar demographic group has chosen. This is an optional filter for the search results. This means that we provide an interactive flexible recommendation list that considers a user's intent more actively, rather than unilaterally. We show the Mean Absolute Error result to evaluate the recommendation and finally show the realization of a prototype that is based on both the iPhone and Android phone environments.

Bayesian Network-Based High-Level Context Recognition for Mobile Context Sharing in Cyber-Physical System

With the recent proliferation of smart phones, they become useful tools to implement high-confidence cyber-physical systems. Among many applications, context sharing systems in mobile environment attract attention with the popularization of social media. Mobile context sharing systems can share more information than web-based social network services because they can use a variety of information from mobile sensors. To share high-level contexts such as activity, emotion, and user relationship, a user had to annotate them manually in previous works. This paper proposes a mobile context sharing system that can recognize high-level contexts automatically by using Bayesian networks based on mobile logs. We have developed a ContextViewer application which consists of a phonebook and a map browser to show the feasibility of the system. Experiments of evaluating Bayesian networks and performing the SUS test confirm that the proposed system is useful.

A channel recommendation system in mobile environment

Digital multimedia broadcasting service has been at the center of developing issues in mobile environment. In contrast to traditional multimedia broadcasting systems, mobile devices have limit of information handling capacity. In order to solve the problem, this paper presents a personalized channel recommendation system at client side in mobile environment. The system includes four modules: client manager agent, monitoring agent, data preparation agent and recommendation agent. Within the recommendation agent, we develop a recommendation algorithm using users' preference transitions for the channels. Also, we design and implement the prototype system on the wireless Internet platform for interoperability. In the experiment, we compare the proposed algorithm with a conventional method. The experimental results show that the proposed recommendation system can provide better performance than the conventional method.

The performance analysis of a multi-carrier CDMA system in mobile environment

In this paper, several detection schemes are studied for a multi-carrier code division multiple access (MC-CDMA) system in the downlink case. Both analytical methods and system simulations are used to examine the performance of those detection schemes. The inter-symbol interference (ISI) can be absorbed by guard intervals, so the data in each subcarrier can be well equalized in slowly fading environment in case of coherent detection. Since each individual subcarrier of an MC-CDMA system is flat fading, it is possible to apply differential modulation schemes with non-coherent reception at subcarrier level. In the ideal case, the non-coherent reception provides worse performance than the coherent reception. However, the performance gap between coherent and differential reception reduces with increasing channel estimation and equalization errors. In the extreme cases, in fast-fading environment, the performance of differential detection may even exceed that of a coherent receiver with practical channel estimation methods. This is proved by the simulation results when a simple coherent detection scheme and a differential phase detection scheme are compared. It is also shown in this paper that with a simple equalizer, an MC-CDMA system can provide good performance in multi-user and multipath fading environments. Copyright © 2004 AEI.