• Proceedings of the Korea Multimedia Society Conference
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• 2004.05a
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• pp.334-337
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• 2004

컨텐츠를 저작하기 위하여 멀티미디어 요소로 사용되는 그래픽, 이미지, 오디오, 비디오 등의 여러 요소의 상호작용적인 관계를 저작할 수 있는 MPEG-4에 관하여 많은 연구가 이루어지고 있다. 이러한 연구의 결과는 저작과 재생뿐만 아니라 서비스, 유통 등에 대해 전반적으로 다루어진다. 개인용 컴퓨터의 사용과 더불어 휴대폰, PDA와 같은 무선 인터넷의 사용 빈도가 현저하게 증가하고 있으며, 모바일 환경에 MPEG-4 적용을 시도하는 것은 큰 의의를 가진다. 본 논문에서는 PC 환경에서 개발된 멀티미디어 컨텐츠 저작도구를 바탕으로 PDA 환경에 적합한 멀티미디어 컨텐츠 저작 방법을 제시하고 제안한 방법을 적용한 저작도구를 제시한다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.262-264
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• 2003

본 논문에서는 광역 및 근거리 우선 접속을 지원하는 PDA상에서 각 무선접속들 간의 상호 연동 및 핸드오프 방안을 설계하고 제시한다. 즉, 근거리 망인 블루투스와 광역 망인 COMA간의 연동 및 핸드오프 방식을 설계 제안하며 이동성과 연결성을 보장한다. 또한 홈 네트워크 상에서 홈 서버와 PDA간의 상호연동 접속 및 핸드오프 방안을 적용하고 테스트한다.

• Clinical and Experimental Pediatrics
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• v.46 no.11
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• pp.1080-1084
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• 2003

Purpose : To compare perinatal characteristics, clinical courses, and overall morbidity between respiratory distress syndrome(RDS) with patent ductus arteriosus(PDA) and RDS without PDA in neonates. Methods : Eighty-three neonates who were diagnosed and treated for RDS in the neonatal intensive care unit(NICU) from Jan. 2000 to Dec. 2002 were included in this study. RDS was complicated with PDA(group A) in 17 patients and not complicated in 66(group B). PDA was diagnosed by echocardiogram in neonates with congestive heart failure symptom, cardiac murmur or chest X-ray findings of cardiomegaly or pulmonary edema. A retrospective study was undertaken of the perinatal characteristics and overall morbidity in group A and group B. Results : The birth weight and gestational periods of group A were less compared with group B. There was more perinatal asphyxia in group A. Incidence of overall morbidity such as bronchopulmonary dysplasia, intraventricular hemorrhage and death was higher in group A. Intravenous indomethacin was administered in 17 PDA infants. Conclusion : The perinatal characteristics in the two groups showed a significant difference. Incidence of overall morbidity in the two groups showed significant differences, however, there is no simple conclusion to draw because we didn't do multifactorial analyses to rule out other many risk factors affecting morbidity, such as gestational weeks or birth weight.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1594-1617
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• 2018

In this paper, we consider a spectrum access scenario which consists of two groups of users, namely Primary Users (PUs) and Secondary Users (SUs) in Cooperative Cognitive Radio Networks (CCRNs). SUs cooperatively relay PUs messages based on Amplify-and-Forward (AF) and Decode-and-Forward (DF) cooperative techniques, in exchange for accessing some of the spectrum for their secondary communications. From the literatures, we found that the Conventional Distributed Algorithm (CDA) and Pragmatic Distributed Algorithm (PDA) aim to maximize the PU sum-rate resulting in a lower sum-rate for the SU. In this contribution, we have investigated a suit of distributed matching algorithms. More specifically, we investigated SU-based CDA (CDA-SU) and SU-based PDA (PDA-SU) that maximize the SU sum-rate. We have also proposed the All User-based PDA (PDA-ALL), for maximizing the sum-rates of both PU and SU groups. A comparative study of CDA, PDA, CDA-SU, PDA-SU and PDA-ALL is conducted, and the strength of each scheme is highlighted. Different schemes may be suitable for different applications. All schemes are investigated under the idealistic scenario involving perfect coding and perfect modulation, as well as under practical scenario involving actual coding and actual modulation. Explicitly, our practical scenario considers the adaptive coded modulation based DF schemes for transmission flexibility and efficiency. More specifically, we have considered the Self-Concatenated Convolutional Code (SECCC), which exhibits low complexity, since it invokes only a single encoder and a single decoder. Furthermore, puncturing has been employed for enhancing the bandwidth efficiency of SECCC. As another enhancement, physical layer security has been applied to our system by introducing a unique Advanced Encryption Standard (AES) based puncturing to our SECCC scheme.

• The Journal of the Korea Contents Association
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• v.8 no.7
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• pp.93-102
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• 2008

With the advance of ubiquitous environment, a lot of changes occur in various kinds of applications. The marketing for festivals is not an exception. Due to the needs for changes in the festival marketing, researches about active marketing suitable for ubiquitous environment are increasing. The purpose of this paper is to develop a u-pamphlet based on PDA and QR code. In this paper, we focus on Jeju Jeongweol Daeboreum Fire Festival, shortly Jeju Fire Festival, as a pamphlet content, which is one of the best domestic festivals. When tourists attend Jeju Fire Festival, the proposed u-pamphlet provides various forms of Jeju Fire Festival information either by accessing digital content stored in PDA directly or by interpreting QR code in the Festival area and connecting remote digital content indirectly. In addition, in order to analyze the necessity, the usefulness, the functionality, and the technical barriers of the u-pamphlet, we make a questionnaire after we exhibit our u-pamphlet.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.4
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• pp.430-435
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• 2006

In this paper, we propose a method based on multimodal biometrics system using the face and signature under ubiquitous computing environments. First, the face and signature images are obtained by PDA and then these images with user ID and name are transmitted via WLAN(Wireless LAN) to the server and finally the PDA receives verification result from the server. The multimodal biometrics recognition system consists of two parts. In client part located in PDA, user interface program executes the user registration and verification process. The server consisting of the PCA and LDA algorithm shows excellent face recognition performance and the signature recognition method based on the Kernel PCA and LDA algorithm for signature image projected to vertical and horizontal axes by grid partition method. The proposed algorithm is evaluated with several face and signature images and shows better recognition and verification results than previous unimodal biometrics recognition techniques.

• Clinical and Experimental Pediatrics
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• v.53 no.12
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• pp.1012-1017
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• 2010

Purpose: Transcatheter closure has become an effective therapy in most patients with patent ductus arteriosus (PDA). However, there are difficulties in transcatheter closure of PDA in small children. We reviewed clinical outcomes of transcatheter closure of PDA in children weighing less than 10 kg in a single center. Methods: Between January 2003 and December 2009, 314 patients with PDA underwent transcatheter closure in our institute. Among them, 115 weighed less than 10 kg. All of these patients underwent transcatheter closure of PDA using either COOK Detachable $Coil^{(R)}$, PFM Nit-$Occlud^{(R)}$, or Amplatzer duct $occluder^{(R)}$. A retrospective review of the treatment results and complications was performed. Results: The mean age of patients was $9.1{\pm}5.9$ months (median, 8 months), and mean weight was $7.6{\pm}1.8kg$ (median, 7.8 kg). The mean diameter of PDA was $3.2{\pm}1.4mm$ (median, 3 mm). Complete occlusion occurred in 113 patients (98%). One patient was sent to surgery because of a failed attempt at device closure, and another patient had a small residual shunt after device placement. The average mean length of hospital stay was $3.0{\pm}3.3$ days, and mean follow-up duration was $21.0{\pm}19.6$ months. There were no major complications in any of the patients. Conclusion: Transcatheter closure of PDA is considered safe and efficacious in infants weighing less than 10 kg. With sufficient experience and further effort, transcatheter closure of PDA can be accepted as the gold standard of treatment for this group of patients.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.690-695
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• 2006

This study was carried out to develop a system for forest resources inventory using PDA. The Forest Inventory Software running on PDA was developed based on a Forest Resources Inventory Method by Korea Forestry Service and 4th National Forest Inventory Method. The forest inventory data stored in PDA contains sea level and GPS positioning data. Forest inventory input items are 34 tree species, 18 diameter class by each tree species, number of trees, tree height per each diameter class, thickness of bark, and annual growth of tree. Application test of the software with the forest workers shorted that, hours of forest works were remarkably reduced. It is possible to do forest inventory effectively using Forest Inventory Software developed by this study. Therefore, investigation and management expenses can be reduced and labor productivity will be improved.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.53-60
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• 2014

Different kinds of post-deposition annealing (PDA) by a rapid thermal process (RTP) are used to enhance the field-effect passivation of $Al_2O_3$ film in crystal Si solar cells. To characterize the effects of PDA on $Al_2O_3$ and the interface, metal-insulator semiconductor (MIS) devices were fabricated. The effects of PDA were characterized as functions of RTP temperature from $400{\sim}700^{\circ}C$ and RTP time from 30~120 s. A high temperature PDA can retard the passivation of thin $Al_2O_3$ film in c-Si solar cells. PDA by RTP at $400^{\circ}C$ results in better passivation than a PDA at $400^{\circ}C$ in forming gas ($H_2$ 4% in $N_2$) for 30 minutes. A high thermal budget causes blistering on $Al_2O_3$ film, which degrades its thermal stability and effective lifetime. It is related to the film structure, deposition temperature, thickness of the film, and annealing temperature. RTP shows the possibility of being applied to the PDA of $Al_2O_3$ film. Optimal PDA conditions should be studied for specific $Al_2O_3$ films, considering blistering.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.5
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• pp.590-597
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• 2002

Currently, with the increasing demand for combining cellular phone and PDA, various kinds of PDA-phones are being developed. A typical PDA-phone consists of a CDMA processor and a PDA processor. Generally, a UART serial communication port is used for inter-processor communication. However, the CDMA standard will need more data bandwidth over 2Mbps with the emergence of IMT-2000. The bandwidth requirement is beyond the capability of UART. In this paper, several inter-processor communication mechanisms are analyzed and especially Dual Port Memory and USB were chosen as the candidates for the new communication mechanism. A prototype PDA-phone board has been implemented for experiment. The experimental result shows that Dual Port Memory is better than USB in cost performance.