• Journal of the Institute of Convergence Signal Processing
• /
• v.11 no.4
• /
• pp.255-262
• /
• 2010

Recently, we are living in the world of information and ubiquitous technology strayed away from the fixed network systems resulting in an increase of using mobile terminals which is convenient for mobility and functionality. Because the diversification of mobile devices to communicate between disparate mobile terminals is difficult, the two kinds of operating systems and hardware for data communication between the terminals is needed to convert the data. The proposed instant messenger design in MRP-S3C2440A (Windows CE 5.0) and Nexio XP30 (Windows CE .NET 4.1) were tested and applied. Usually the mobile terminal has an information on a central server. Sender terminal receives the message according to the characteristics of the terminal after converting was sent to the receiving terminal. Receiving-side terminal without a separate conversion process, it was the output terminals. This paper deals with the proposal and implementation of designing an instant messenger application program between the two different mobile terminals and network systems.

• The KIPS Transactions:PartA
• /
• v.9A no.4
• /
• pp.413-420
• /
• 2002

It it essential to get the exact location information of products for a warehouse management. It is very hard, however, to know the location of products which change their location in warehouse frequently This causes the effective warehouse management to be almost impossible. In this paper, we suggest a new location management system for such a SKU(Stock Keeping Unit) with high mobility. The system is composed of RFID (Radio Frequency IDentification), a management terminal with wireless LAN, mobile devices (Cellular Phone & PDA), and a central management system. As a model of a SKU with high mobility, we selected a used-car stored in a large-scale warehouse. We designed and implanted used-car location management system. After analyzing the operations of each position in used-car warehouse where the system will run, we implemented each function. This research shows that an embedded system with wireless LAN is able to know the status of coming in and cut and location of a SKU with high mobility in warehouse very accurately in real time. Therefore, it makes the warehouse to be controlled systematically.

• The KIPS Transactions:PartA
• /
• v.9A no.4
• /
• pp.485-490
• /
• 2002

As the products of internet appliance, such as digital TV, internet set-top box, and internet phone, are continually produced, the market of real time operating system which controls those products is being highly increased. ETRI developed the extensible real time operating system, Qplus-P, which can be used from PDA to internet set-top box and home server. This paper describes the design and implementation of C standard library for real-time operating system Qplus-P. The Qplus-P C standard library follows EL/IX API level, which is proposed to the real-time operating system international standard by the RedHat. And, the C standard library functions, which are needed to support the Tiny-X and Kaffe, are also implemented. The implemented C standard library can reduce the size of library about 30% compare to the C library that does not follow EL/IX API level.

• The KIPS Transactions:PartB
• /
• v.9B no.5
• /
• pp.533-540
• /
• 2002

We can buy products everywhere from Web-based shopping mall using desktop, cellular phone or PDA. To guarantee the various services for different equipment, shopping mail systems should allow a lot of different size or quality of images to provide a good service to their customers. Despite of same product image, each shopping mall saves the image in its storage space individually. Furthermore, all the product images in each shopping mall are stored as images of different quality. It may waste resources of shopping mail server and bring us developmental overhead. It is difficult to update all the images for product that is used by distributed e-catalog in everywhere. In this paper, we extended the proposed Web Image Server (WIS) for sharing one image with all clients and processing Image dynamically, so that we strengthened the function of managing shopping mall as a client of WIS and added the function of recording clients'log file and image catalog for shopping mall. We measured the response time from WIS and conventional e-Commerce site using by WAS which is one of the stress test tools for Web application. Furthermore, we measured WIS responses image requests in reasonable time when the current user is increased.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.1
• /
• pp.70-74
• /
• 2010

As the storage capacity of the flash memories increased portable devices began to store mass amount of multimedia data on flash memory. Therefore, there has been a need for an effective data management scheme by indexing structure. Among many indexing schemes, M-tree is well known for it's suitability for multimedia data with high dimensional matrix space. Since flash memories have writing operation restriction, there is a performance limitation in indexing scheme with frequent write operation. In this paper, a new node split method with reduced write operation for m-tree indexing scheme in flash memory is proposed. According to experiments the proposed method reduced the write operation to about 7% of the original method. The proposed method will effectively construct an indexing structure for multimedia data in flash memories.

• The KIPS Transactions:PartA
• /
• v.15A no.6
• /
• pp.325-334
• /
• 2008

Flash memory is widely used as a storage medium for mobile devices such as cell phones, MP3 players, PDA's due to its tiny size, low power consumption and shock resistant characteristics. Additionally, some computer manufacturers try to replace hard-disk drives used in Laptops or personal computers with flash memory. More recently, there are some literatures on developing a flash memory-aware $B^+$-tree index for an efficient key-based search in the flash memory storage system. They focus on minimizing the number of "overwrites" resulting from inserting or deleting a sequence of key values to/from the $B^+$-tree. However, in addition to this factor, the size of a physical page allocated to a node can affect the maintenance cost of the $B^+$-tree. In this paper, with diverse experiments, we compare and analyze the costs of construction and search of the $B^+$-tree and the space requirement on flash memory as the node size increases. We also provide sorting-based or non-sorting-based algorithms to be used when inserting a key value into the node and suggest an header structure of the index node for searching a given key inside it efficiently.

• Journal of the Korea Society of Computer and Information
• /
• v.18 no.12
• /
• pp.207-215
• /
• 2013

The general opinion about the notion of cyberbullying hasn't existed yet, but in related laws it is defined as the entire behavior causing the counterpart to suffer the pain by continuously and repeatedly psychologic offending toward specific students with information and telecommunication products such as the Internet and mobile phones, and spreading the private information or false facts related with specific students. Recently a number of accidents related with abuse of cyberbullying are being broadcast on a variety of mass media, and the argument about the severity and countermeasures against cyberbullying is moving onward. This study has a purpose as suggesting the practical alternatives to prevent cyberbullying victim of middle school students by arguing cyberbullying of middle school students and analyzing the relationship between the general features such as victimized experience and frequency and the emotional behaviors according to victimized experience. As the result of this study, cyberbullying victimized experience has a significant effect on the emotional behavior such as depression, aggression, and academic stress. As political implication, this study suggests the practical alternatives to prevent cyberbullying of middle school students based on the analysis result.

• Journal of Advanced Navigation Technology
• /
• v.24 no.6
• /
• pp.601-606
• /
• 2020

In this paper, we designed a microstrip patch antenna that can be applied to the Wimax/LTE 5G system among wireless media usable in coastal ships. The substrate of the proposed antenna is FR-4 (er=4.3), the size is 22 mm × 30 mm, and it can be used in the 3.5 GHz and 5.8 GHz bands of Wimax/LTE 5G by constructing a simple structure using a microstrip patch antenna. CST Microwave Studio 2014 was used for simulation, and the gain of the simulation result is 2.41dB at 2.4 GHz and 3.96 dB at 3.5 GHz. S-Parameter also showed a result of less than -10 dB (VSWR 2:1) in the desired frequency band, and designed a small variable and a miniaturized antenna so that the antenna can be used in mobile phones or electronic devices.

• Journal of Appropriate Technology
• /
• v.7 no.2
• /
• pp.211-215
• /
• 2021

It is estimated that there are 40 million people with AIDS worldwide, with most cases occurring mainly in developing countries. HIV, the virus that causes AIDS, is infected with CD4+ T cells in the blood and gradually destroys CD4+ T cells for several months to 10 years, thereby lowering the patient's immune function. AIDS patients who have weakened immunity in this way will die from various diseases. The current method for counting the number of CD4+ T cells is usually performed by flow cytometry. The flow cytometry method has the advantage of high accuracy, but it is difficult to use in developing countries because it requires skilled professionals and equipment is expensive. As a result of this study, a device for AIDS screening was developed by capturing leukocytes from a small amount of 5 ㎕ blood through a microfilter and analyzing CD4+ T cells and CD8+ T cells from the captured cells. cheaper and easier to carry and use than current test equipment.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.1
• /
• pp.141-151
• /
• 2022

Wireless earphones are products that are consumed together with smart devices (mobile phones, etc), and there is no twisting and convenience compared to general earphones. However, due to the lack of information on the quality of wireless earphones, consumers tend to purchase products based on brand awareness, and manufacturers deliver information to consumers based on different standards for each product due to the lack of standards for measurement methods for quality evaluation. In particular, the playback time of wireless earphones is a factor that can directly affect consumers' purchases, so it is necessary to prepare a standardized test method to properly measure it. This paper introduces the current status of wireless earphones and related standard trends, and proposes a method for measuring the audio playback time of wireless earphones developed through this. In addition, this measurement method will be proposed as an international standard (IEC) after being established as the national standard, the Korean Industrial Standard (KS).