• Journal of electromagnetic engineering and science
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• v.4 no.3
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• pp.124-127
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• 2004

A novel printed inverted-F antenna for dual-band WLAN is presented. The proposed design is based on the folded quarter-wave antennas, which have a conductor plate having two arms. An extremely thin prototype antenna is fabricated according to the simulation result. The obtained antenna can perform in IEEE802.11a, b(2.4～2.484 GHz and 5.15～5.35 GHz bands) and be adopted for laptop applications. All the measurements are performed in the actual test fixture.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.177-178
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• 2012

In spite of its compactness and lightness, conventioan boost converter is not preferred for the charge applications. In this paper, a non-isolated boost converter topology for the Li-Ion battery suitable for fuel cell powered laptop computer is proposed and analyzed. The proposed converter has an additional inductor at the output to reduce the output ripple current and voltage. This feature makes it suitable for the charger application by eliminating the disadvantages of the conventional non-isolated boost converter mentioned above.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.10
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• pp.1835-1839
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• 2008

Power management is a very important issue in portable electronic applications. Portable electronic devices require very efficient power management like LDO to increase the battery life. As the voltage variation of battery power is large in the application of cell phone, camera, laptop, automotive, industry application and so on, battery power is not directly used and LDO is used to supply the power of internal circuit. Besides, LDO can supply DC voltage that is lower than bauer voltage and constant DC voltage that is not related to largely fluctuated battery power. In the study, the power-save mode current and IR-drop characteristics are analyzed from a LDO with on-chip fabricated in 0.18-um CMOS technology.

• Korean Journal of Mathematics
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• v.29 no.1
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• pp.137-167
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• 2021

Spherical fuzzy set (SFS) is also one of the fundamental concepts for address more uncertainties in decision problems than the existing structures of fuzzy sets, and thus its implementation was more substantial. The well-known sine trigonometric function maintains the periodicity and symmetry of the origin in nature and thus satisfies the expectations of the experts over the multi parameters. Taking this feature and the significance of the SFSs into the consideration, the main objective of the article is to describe some reliable sine trigonometric laws (ST L) for SFSs. Associated with these laws, we develop new average and geometric aggregation operators to aggregate the Spherical fuzzy numbers (SFNs). Then, we presented a group decision- making (DM) strategy to address the multi-attribute group decision making (MAGDM) problem using the developed aggregation operators. In order to verify the value of the defined operators, a MAGDM strategy is provided along with an application for the selection of laptop. Moreover, a comparative study is also performed to present the effectiveness of the developed approach.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1188-1190
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• 2003

Taipei Watershed Management Bureau (WRATB) is a government agency entitled for water resources protection at two major watersheds in order to provide drinking water for about four millions population in Taipei on a sustainable basis. At WRATB, there are two major public sewage treatment facilities which can convert sewage in each watershed into an acceptable state before they were discharged into rivers. More than 82% of household wastewater have been collected and treated by the two public sewage systems. However, households at remote area still need more effective sewage management prescriptions. The objective of this paper is to implement geographic information systems in order to provide more effective approaches that sewage management can be easier and cost effective. ArcIMS was implemented for Internet browsing and map server of those sewage facilities on personal computers, laptop computers. In the open field, ArcPAD was implemented with personal digital assistant (PDA) such that compact flash type's global positioning systems (GPS) and digital camera can be utilized with PDA. All sewage facilities digital files were convert into ArcMap format files. MapObjects and visual BASIC were used to create sewage application modules to meet every single technician personal flavor. ASP.NET was implemented for Internet database manipulations of all sewage databases. Mobile GIS was the key component of GIS applications in the open field for sewage management on a basis of house by house. Houses at remote area, which can not cover by the two public sewage systems, were managed by PDA and laptop computers with GPS and digital camera. Sewage management at Taipei Watershed Management Bureau is easier both in the open field and in the office. Integration of GPS, GIS, and PDA makes sewage management in the open field much easier. ArcIMS, MapObjects, ASP.NET and visual BASIC make sewage management can be done in the office and over Internet.

• Journal of the Korea Society of Computer and Information
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• v.19 no.2
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• pp.125-132
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• 2014

In this paper, we present marker-less fingertip and brush tracking system with inexpensive web camera. Parallel computation using CUDA is applied to the tracking system. This tracking system can run on inexpensive environment such as a laptop or a desktop and support for real-time application. We also present realistic water-based sign pen drawing model and implementation. The realistic drawing application with our inexpensive real-time fingertip and brush tracking system shows us the art class of the future. The realistic drawing application, along with our inexpensive real-time fingertip and brush tracking system, would be utilized in test-bed for the future high-technology education environment.

• Journal of KIISE
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• v.42 no.6
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• pp.691-698
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• 2015

Application launch time is an important performance metric to user experience in desktop and laptop environment, which mostly depends on the performance of secondary storage. Application launch times can be reduced by utilizing solid-state drive (SSD) instead of hard disk drive (HDD). However, considering a cost-performance trade-off, utilizing SSDs as caches for slow HDDs is a practicable alternative in reducing the application launch times. We propose a new SSD caching scheme which migrates data blocks from HDDs to SSDs. Our scheme operates entirely in the file system level and does not require an extra layer for mapping SSD-cached data that is essential in most other schemes. In particular, our scheme does not incur mapping overheads that cause significant burdens on the main memory, CPU, and SSD space for mapping table. Experimental results conducted with 8 popular applications demonstrate our scheme yields 56% of performance gain in application launch, when data blocks along with metadata are migrated.

• Journal of the HCI Society of Korea
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• v.8 no.2
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• pp.1-8
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• 2013

In previous study, we developed a guidance system outdoors for person with visual impairment to be able to walk safely to the destination. The volunteers are exposed to dangerous situations since they are performed to the experiments in the outdoors. In order to solve the problem, we propose an interactive application that monitors the volunteer wearing guidance system and warns remotely the volunteer about dangerous situations. The application is used to remote wireless communication with guidance system through Bluetooth module that is built in a laptop computer, without additional device. Therefore, we can monitor in real time user's location and guided contents to user, and it is possible to check a path to the destination and POI (Point of Interest) coordinate values. As using a proposed monitoring application, it is possible to perform safe experiment with the rapid situation awareness and fast detection of dangerous.

• Journal of Korea Multimedia Society
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• v.20 no.2
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• pp.101-107
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• 2017

LabVIEW coding for video dehazing was developed. The dark channel prior proposed by K. He was applied to remove fog based on a single image, and K. B. Gibson's median dark channel prior was applied, and implemented in LabVIEW. In other words, we improved the image processing speed by converting the existing fog removal algorithm, dark channel prior, to the LabVIEW system. As a result, we have developed a real-time fog removal system that can be commercialized. Although the existing algorithm has been utilized, since the performance has been verified real - time, it will be highly applicable in academic and industrial fields. In addition, fog removal is performed not only in the entire image but also in the selected area of the partial region. As an application example, we have developed a system that acquires clear video from the long distance by connecting a laptop equipped with LabVIEW SW that was developed in this paper to a 100~300 times zoom telescope.

• 전자공학회논문지 IE
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• v.47 no.3
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• pp.14-18
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• 2010

In this paper, we describe a CMOS DC-DC converter with a variable output voltage(5-7V @100mA) for a portable battery-operated system applications. The proposed DC-DC converter is used along with a Pulse-Frequency Modulation (PFM) method and consists of reference circuit, a feedback resistor, a controller, and an internal oscillator. The integrated DC-DC converter with two external passive components(L,C) has been designed and fabricated on a 0.5um 2-poly 3-metal CMOS process and could be applied to the Personal Digital Assistants(PDA), cellular Phone, Laptop Computer, etc.