• Journal of Korea Multimedia Society
• /
• v.17 no.8
• /
• pp.968-976
• /
• 2014

Authentication methods on smartphone are demanded to be implicit to users with minimum users' interaction. Existing authentication methods (e.g. PINs, passwords, visual patterns, etc.) are not effectively considering remembrance and privacy issues. Behavioral biometrics such as keystroke dynamics and gait biometrics can be acquired easily and implicitly by using integrated sensors on smartphone. We propose a biometric model involving keystroke dynamics for implicit authentication on smartphone. We first design a feature extraction method for keystroke dynamics. And then, we build a fusion model of keystroke dynamics and gait to improve the authentication performance of single behavioral biometric on smartphone. We operate the fusion at both feature extraction level and matching score level. Experiment using linear Support Vector Machines (SVM) classifier reveals that the best results are achieved with score fusion: a recognition rate approximately 97.86% under identification mode and an error rate approximately 1.11% under authentication mode.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.140-142
• /
• 2016

Recently, rapid innovation of Smartphone is changing the paradigm of our daily life. Smartphone users, opinion experts more than 99 percent of the economically active population is using, it has reached the saturation past the early stages of formation. Smartphone is equipped with a general purpose OS possible the implementation of high performance environment similar level as a personal computer. Thus, it is a mobile communication terminal scalable which can be removed or installed various applications. Such extensibility, it is possible to use different applications through the Apps store. Also, it is also possible various services which are location based service. In this research, we aim to analyze factors influencing of cloud computing service on reusing intention of smartphone. In addition, we aim to analyze the causal relationship from perceived value to reusing intention. This study suggests practical and theoretical implications based on the results.

• KIPS Transactions on Software and Data Engineering
• /
• v.2 no.1
• /
• pp.49-54
• /
• 2013

Activity recognition using smartphone accelerometer suffers from the user dependency problem that acceleration patterns of one user differ from those of others for the same activity. Moreover, it also suffers from the position dependency problem since a smartphone may be placed in any pockets or hands. In order to overcome these problems, this paper proposes an effective activity recognition method which is less dependent with both specific users and specific positions of the smartphone. Based on the proposed method, we implement a real-time activity recognition system working on an Android smartphone. Throughout some experiments with 6642 examples collected from different users and different positions, we investigate the performance of our activity recognition system.

• KIPS Transactions on Software and Data Engineering
• /
• v.2 no.6
• /
• pp.395-402
• /
• 2013

We propose an accelerometer-based gesture recognition method for smartphone users. In our method, similarities between a new time series accelerometer data and each gesture exemplar are computed with DTW algorithm, and then the best matching gesture is determined based on k-NN algorithm. In order to investigate the performance of our method, we implemented a gesture recognition program working on an Android smartphone and a gesture-based teleoperating robot system. Through a set of user-mixed and user-independent experiments, we showed that the proposed method and implementation have high performance and scalability.

• Journal of Digital Convergence
• /
• v.15 no.3
• /
• pp.201-209
• /
• 2017

This paper is a smartphone object recognition system using hierarchical convolutional neural network. The overall configuration is a method of communicating object information to the smartphone by matching the collected data by connecting the smartphone and the server and recognizing the object to the convergence neural network in the server. It is also compared to a hierarchical convolutional neural network and a fractional convolutional neural network. Hierarchical convolutional neural networks have 88% accuracy, fractional convolutional neural networks have 73% accuracy and 15%p performance improvement. Based on this, it shows possibility of expansion of T-Commerce market connected with smartphone and broadcasting media.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.21 no.5
• /
• pp.95-102
• /
• 2021

The urinalysis, which is universally accessible to the general public, has disadvantages of being less objective using sight and purchasing a separate portable urinalysis machine. However, due to the high penetration rate and performance improvement of smartphone created by the development of mobile communication technology, research on urinalysis services using smartphone has been conducted. In this paper, a new urinalysis screening application based on smartphone was developed by supplementing the limitations of the previously studied urinalysis services. The key technology of the application is urinalysis recognition algorithm and urinalysis pad color determination algorithm through image-processing and contour detection. In order to confirm the performance of the developed application, urinalysis strip was photographed and analyzed from various backgrounds and angles.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.219-222
• /
• 2013

Recently, rapid innovation of Smartphone is changing the paradigm of our daily life. With the launch of Apple iPhone, there is an explosion of interest in Smartphone itself as well as Internet-based services using Smartphone are being revitalized. Smartphone users, opinion experts more than 99 percent of the economically active population is using, it has reached the saturation past the early stages of formation. Smartphone is equipped with a general purpose OS possible the implementation of high performance environment similar level as a personal computer. Also, it is a mobile communication terminal scalable which can be removed or installed various applications. New information technology like Smartphone gives us a very important and interesting research issue that is to find and prove the factors influencing the purchase intention. At this point, study identifying on the influence factors to the behavioral intention of Smartphone is very important. This study was targeted a total of 99 research papers that are setting up the related Smartphone in among the research papers published in domestic academic journals since 2008. Empirical research related behavioral intention using was summarized on the papers 76.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.25 no.3
• /
• pp.519-530
• /
• 2015

With the development of technologies, smartphone provides excellent extensibility and performance. Users can install application programs easily in smartphone, so they can use smartphone in various way. In the past, users used smartphone for enhancing security in personal computer. Nowadays, smartphone has become a major target for attackers. Therefore we needs a reliable portable device for smartphone security. There are various wearable devices such as smartglasses and smartwatches, so they can be used for enhancing security in smartphone. In this paper, we study about that smartwatches can be role for enhancing smartphone security, and we implement transaction information verification scheme, Transaction information verification scheme based on CAPTCHA and CAPTCHA based transaction OTP scheme and experiment with users in prototype application.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.4
• /
• pp.739-751
• /
• 2014

We are using our smartphone for our business as well as ours lives. Thus, user's privacy data and a company secret are stored at smartphone. By the way, the saved data on smartphone database can be exposed to a malicous attacker when a malicous app is installed in the smartphone or a user lose his/her smartphone because all data are stored as form of plaintext in the database. To prevent this disclosure of personal information, we need a database encryption method. However, if a database is encrypted, it causes of declining the performance. For example, when we search specific data in condition with encrypted database, we should decrypt all data stored in the database or search sequentially the data we want with accompanying overhead[1]. In this paper, we propose an efficient and searchable encryption method using variable length bloom filter under limited resource circumstances(e.g., a smartphone). We compare with existing searchable symmetric encryption. Also, we implemented the proposed method in android smartphone and evaluated the performance the proposed method. As a result through the implementation, We can confirm that our method has over a 50% improvement in the search speed compared to the simple search method about encrypted database and has over a 70% space saving compared to the method of fixed length bloom filter with the same false positive rate.

• Journal of information and communication convergence engineering
• /
• v.9 no.6
• /
• pp.695-700
• /
• 2011

Smartphone has formed a new market and introduced a new environment. They have an operating system like PCs, enabling free installation and removal of application programs. As the number of Smartphone users is increasing, more personal information is also exposed to malicious codes. There are problem of modification and deletion of files, battery consumption, and information leakage due to malicious codes. As the needs of Smartphone antivirus solutions are increasing, the antivirus solutions should be evaluated with quality characteristics. In this paper, we propose an effective evaluation method for functionality and performance of Smartphone antivirus solutions, and the best practices for evaluation.