Earticle

Nowadays learning has developed to a new way of anywhere and anytime by using mobile devices called m-learning which can provide flexibility, independency and creativity in academic environment. Most studies about m-learning are for higher education and the most users of m-learning are higher education students. Although developed countries are using m-learning in educational sectors, most of the Middle East countries are far from m-learning, and facing number of challenges. In Iran m-learning is still in early stage of implementation in higher education and in terms of technical and infrastructural aspects there is a vast gap in compare with developed countries. Although technical and infrastructural difficulties are one of the significant aspects in implementation and integration of m-learning technologies in education, the technology will not be successful if could not adopt with users. Due to the importance of user adoption with m-learning, there are limited studies about m-learning adoption in higher education of Iran. This paper attempts to review on technical and infrastructural aspects that facilitate m-learning which have effect on adoption of Iran higher education system. The review of the trend in the literature provides a reference for higher education institutes for decision making in developing m-learning for their students.

As smartphone users grow, mobile operators are trying to standardize and commercialize Rich Communication Suite (RCS), which is a next-generation messaging service, so that it can replace legacy messaging services. However, it is not enough to spread RCS widely to the users only by publishing an RCS app. To increase the use of RCS, a web-based open API for common RCS capabilities is needed. By using the API, Internet-based developers can create applications that make use of the RCS capabilities with less effort and time. This paper proposes a lightweight Comet-based open API to allow mobile operators to expose useful information and capabilities to application developers. The system architecture of the open API framework and call flow between relevant nodes are defined. In addition, examples of protocol translations on the framework are provided.

The Constrained Application Protocol (CoAP) is a specialized web transfer protocol proposed by the IETF for use in IoT environments. CoAP was designed as a lightweight machine-to-machine protocol for resource constrained environments. Due to the strength of low overhead, the number of CoAP devices is expected to rise rapidly. When CoAP runs over UDP for wireless sensor networks, CoAP needs to support congestion control mechanisms. Since the default CoAP defines a minimal mechanism for congestion control, several schemes to improve the mechanism have been proposed. To keep CoAP lightweight, the majority of the schemes have been focused mainly on how to measure RTT accurately and how to set RTO adaptively according to network conditions, but other approaches such as rate-based congestion control were proposed more recently. In this paper, we survey the literature on congestion control for CoAP and discuss the future research directions.

Sensors collect information for Internet of Things (IoT)-based services. However, indoor construction sites have a poor communication environment and many interfering elements that make it difficult to collect sensor information. In this study, a network was constructed between a Bluetooth Low Energy (BLE)-based IoT device based on a serverless IoT framework and a router. This experimental environment was applied to large- and small-scale indoor construction sites. Experiments were performed to test the communication performance of BLE-based IoT devices and routers at indoor construction sites. An analysis of the received signal strength indication (RSSI) graph patterns collected from the communication between the BLE-based IoT devices and routers for different testbed site situation revealed areas with good communication performance and poor communication performance due to interfering factors. The results confirmed that structural components of the building as well as the materials, equipment, and temporary facilities used in indoor construction interfere with the communication performance. Construction project managers will require improved technical knowledge of IoT, such as optimizing the router placement and matching communication between the router and workers, to improve the communication performance for large-scale indoor construction.

This paper proposes an adaptive threshold watershed algorithm, which is the method used for image segmentation and boundary detection, which extends the region on the basis of regional minimum point. First, apply adaptive thresholds to determine regional minimum points. Second, it extends the region by applying adaptive thresholds based on determined regional minimum points. Traditional watershed algorithms create over-segmentation, resulting in the disadvantages of breaking boundaries between regions. These segmentation results mainly from the boundary of the object, creating an inaccurate region. To solve these problems, this paper applies an improved watershed algorithm applied with adaptive threshold in regional minimum point search and region expansion in order to reduce over-segmentation and breaking the boundary of region. This resulted in over-segmentation suppression and the result of having the boundary of precisely divided regions. The experimental results show that the proposed algorithm can apply adaptive thresholds to reduce the number of segmented regions and see that the segmented boundary parts are correct.

The idea of ensemble learning is to train multiple models, each with the objective to predict or classify a set of results. Most of the errors from a model’s learning are from three main factors: variance, noise, and bias. By using ensemble methods, we’re able to increase the stability of the final model and reduce the errors mentioned previously. By combining many models, we’re able to reduce the variance, even when they are individually not great. In this paper we propose an ensemble model and applied it to classification problem. In iris, Pima indian diabeit and semiconductor fault detection problem, proposed model classifies well compared to traditional single classifier that is logistic regression, SVM and random forest .

The parametrization of the surface plays an important role in the 3D computer graphics and computer vision. Especially, it is essential in 3D mesh editing that manipulates the position of 3D objects on a computer monitor. Because computer monitors are two-dimensional, while vertices of objects that actually want to change are in a three-dimensional virtual space. In this study, we propose a new type of parametrization method that takes advantage of the special properties of circles that are common to local parameterization. Experimental results show that our parameterization method is more efficient in terms of time and space than the standard parameterization method that was designed by Floater et al.

In this paper, we propose the adaptive beamforming algorithm for the MIMO (Multi-Input Multi-Out)-OFDMA(Orthogonal Frequency Division Multiplexing Access)system to improve the performance. The performance of MIMO-OFDMA systems is greatly decreased in the wireless channel environment with multiusers, because the received signals are much distorted by a cochannel interference (CCI) during the space-time decoding. The proposed approach can track the DOA of each signal from the multiple antennas of the desired user without being greatly dependent on the impinging angle. And beams are directed toward the multiple transmitters of the desired user while null beams are directed toward interference directions. Therefore, we can can effectively cancel CCI and mitigate the impairment of delay spread while preserving the STC(space time code) diversity. BER performance improvement is investigated through computer simulation by applying the proposed approach to MIMO-OFDMA system in a multipath fading channel with CCI.

The compiler is the key of the prototyping framework for the new memory system. These compiler-centric prototyping tools have several components, including compiler, linker, assembler, and standard libraries. It takes a lot of cost and man power to develop it all at zero base. Therefore, developer usually use a development framework to develop these prototyping tools efficiently. These development frameworks should be free of licensing issues when considering the commercialization of development results. Thus, developer should investigate the development framework, which is free from licensing issues and that provides all of the development environment to enable actual execution. There are three representative compiler-centric development frameworks: GCC, Clang (LLVM), and MS visual studio. There are some differences depending on the release version among them. And, there are some limitations to the freeware and commercial use. We chose LLVM here to explain the development of prototyping tools. This information will help accelerate the development of prototyping tools and will help reduce system development costs.

This study was a cross-sectional descriptive research that investigate the level of addiction and analyzed the impact of computer game addiction from 20 to 30 years old on communication capabilities. The purpose of this study was to investigate the level of game addiction according to general characteristics and to confirm the effect of computer game addiction on communication ability. There were a total of 220 participants in the study. This survey for this study was a self-reporting questionnaire, research tools for this study were developed by Lee (2000) using game addiction and Communication ability developed by Frits et al., (1999). Data analysis was analyzed with frequency analysis, t-test, ANOVA, and Regression using SPSS 18.0. As a result of analysis, the difference between game addiction and communication ability by gender was appeared to be different under statistical significance levels: game addiction (t=-.9.2, p<0.01), subcomponents of communication ability, concentration (t=7.20, p<0.01), understanding (t=6.13, p<0.01), response (t=6.22, p<0.01), memory (t=2.88, p<0.05). The highest level of game addiction was appeared between 28 and 30 years old under statistical significance (p<0.01). Finally computer game addiction affects understanding, a subcomponent of communication capabilities.

In this paper, we propose a technique for spatially encrypting confidential data into R, G, B planes of color image and extracting spatially encrypted confidential data. The effectiveness of the proposed technique is verified by mathematically analyzing the quality of the stego-image generated using the proposed technique. The proposed technique can hide confidential data securely into cover image by spatially encrypting the confidential data, and can extract confidential data from the stego-image. The quality of the stego-image created by applying the proposed technique is very good. The average value of the quality of the stego-image is 51.14 dB. Therefore, it is not visually recognizable whether the confidential data is hidden in the stego-image. The proposed technique can be widely used for military and intellectual property protection.

The purpose of this study is to investigate Nest Labs (Nest)’s business strategy. The activities based on strategic choices for monetizing connected product are investigated. Nest’s capacity and functionality is to offer a seamless integration of devices, platforms, and services and the “Works with Nest” offers an ecosystem fulfilling the needs of different partners. For monetizing customer data, Nest provides a seamless customer experience supported by product incentives. Nest introduces open APIs to connect its connected products to the wider Internet of things (IoT) and open to “If This, Then That.” The Nest app controls them from one single place. Nest partners with 32 energy providers as of 2017 and they provide energy from renewable and non-renewable energy sources. Nest also creates a sales channels in direct and indirect route and expands is business model to other industries such as home-rental service, ‘AirBnB’ to help consumers become more energy-efficient at home.

As the number of "Mobility Handicapped" increases, the incidence of "Mobility Handicapped" traffic accidents is also increasing. In order to reduce the incidence of traffic accidents in the "Mobility Handicapped", a service providing system for "Mobility Handicapped" is required. Since these services have different data formats, data heterogeneity occurs. Therefore, the system should resolve the data heterogeneity by mapping the format of the data. In this paper, we design DBaaS as a mobility handicapped system for data interoperability. This system provides a service to extend the flashing time of the traffic lights according to the condition of "Mobility Handicapped" on the occurrence of a fall or a crosswalk in a crosswalk where there is a risk of a traffic accident. These services can reduce the incidence of traffic accidents in "Mobility Handicapped".