• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.1
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• pp.171-184
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• 2010

In this work, we develop a novel channel power allocation method for the real-time multimedia over the wireless network environment. Since each frame has different effect on the user perceivable QoS, improving packet loss does not necessarily coincide with perceivable improvements in QoS. A new channel power control scheme is suggested based on the quantified importance of each frame in terms of user perceivable QoS. Dynamic programming formulation is used to obtain optimal transmit power which minimizes power consumption and maximizes user perceivable QoS simultaneously. The experiment is performed by using publicly available video clips. The performance is evaluated using network simulator version 2 (NS 2) and decoding engine is embedded at the client node, and calculated PSNR over the every frame transmitted. Through the semantics aware power allocation (SAPA) scheme, significant improvement on the QoS has been verified, which is the result of unequal protection to more important packets. SAPA scheme reduced the loss of I frame by upto 27% and reduced power consumption by upto 19% without degradation on the user perceivable QoS.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.1
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• pp.123-134
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• 2010

In this paper we propose ubiquitous virtual reality framework and its application for fostering a sustainable content ecosystem in the convergence space of virtual reality and real space. The ubiquitous virtual reality framework supports fundamental infrastructure which consists of platforms for end-users and service providers and dual space management. The platform for the service provider allows experts to generate contents related to real objects while the platform for the end-users allows to consume, share and regenerate the contents contextually augmented over real objects. The dual space management stores, visualizes and provides the contents generated and extended by them for connecting different users and service providers. The proposed framework allows users to continuously generate, share and extend the contents and thus contribute to making multimedia service environment. We also implemented and evaluated the framework consisting of a desktop authoring platform, mobile authoring platform and a dual space management server. We then introduced a promising application scenario to show how the content ecosystem is empowered by ubiquitous virtual reality framework and is realized in our life. Consequently, we are expecting that the ubiquitous virtual reality technology will play a vital role in building continuously evolving multimedia service environment for the future computing environment.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.1
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• pp.80-91
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• 2010

As the volume of image data increases dramatically, its good organization of image data is crucial for efficient image retrieval. Clustering is a typical way of organizing image data. However, traditional clustering methods have a difficulty of requiring a user to provide the number of clusters as a parameter before clustering. In this paper, we discuss an approach for clustering image data that does not require the parameter. Basically, the proposed approach is based on Cross-Association that finds a structure or patterns hidden in data using the relationship between individual objects. In order to apply Cross-Association to clustering of image data, we convert the image data into a graph first. Then, we perform Cross-Association on the graph thus obtained and interpret the results in the clustering perspective. We also propose the method of hierarchical clustering and the method of outlier detection based on Cross-Association. By performing a series of experiments, we verify the effectiveness of the proposed approach. Finally, we discuss the finding of a good value of k used in k-nearest neighbor search and also compare the clustering results with symmetric and asymmetric ways used in building a graph.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.1
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• pp.15-21
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• 2010

This paper proposes the multimedia fingerprinting code insertion algorithm when video content is distributed in P2P environment, and designs the collusion codebook SRP(Small RISC Processor) embedded system for the collusion attack prevention. In the implemented system, it is detecting the fingerprinting code inserted in the video content of the client user in which it requests an upload to the web server and in which if it is certified content then transmitted to the streaming server then the implemented system allowed to distribute in P2P network. On the contrary, if it detects the collusion code, than the implemented system blocks to transmit the video content to the streaming server and discontinues to distribute in P2P network. And also it traces the colluders who generate the collusion code and participates in the collusion attack. The collusion code of the averaging attack is generated with 10% of BIBD code v. Based on the generated collusion code, the codebook is designed. As a result, when the insert quantity of the fingerprinting code is 0.15% upper in bitplane 0~3 of the Y(luminance) element of I-frame at the video compression of ASF for a streaming service and MP4 for an offline offer of video content, the correlation coefficient of the inserted original code and the detected code is above 0.15. At the correlation coefficient is above 0.1 then the detection ratio of the collusion code is 38%, and is above 0.2 then the trace ratio of the colluder is 20%.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.5
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• pp.28-37
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• 2007

IEEE 1451 standard defines an interface for network and transducer. In this paper, We propose an architectural model to configure data acquisition system and wireless smart sensor node based on IEEE 1451 standard. Proposed Network Capable Application Processor(NCAP) supports the task of data acquisition and communication for smart sensor node and network. The NCAP is able to reconfigure without interrupting the functionality of the wireless sensor node and receives the critical information of transducer using the DB. Smart sensor node is able to provide the basic information of sensor in digital format. This digital format is called Transducer Electronic Data Sheet(TEDS), is capable of plug-and-play capability of wireless sensor node and the NCAP. We simplify the format of TEDS and template to apply to wireless network environment. information of TEDS and template is transmitted using ad-hoc routing. This study system uses body temperature sensor and ECG(Electrocardiogram) sensor to provide the medical information service. The format of template is selected by data sheet of the sensor and reconfigured to accurately describe the property of the sensor. DB of NCAP is possible to register new template and information of the property as developing new sensor.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.5
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• pp.38-48
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• 2007

In ubiquitous environment, sensor networks that sense and transmit surrounding data without human intervention will become more important. If sensors are installed for detecting vehicles and measuring their speed in the road and that real-time information is given to drivers, it will be very effective for enhancing safety and controlling traffic in the road. In this paper, we proposed a new reliable and real-time sensor MAC protocol between AP and sensor nodes in order to provide real-time traffic flow information based on ubiquitous sensor networks. The proposed MAC allocates one TDMA slot for each sensor node on the IEEE 802.15.4 based channel structure, introduces relayed communication for distant sensors, and adopts a frame structure that supports retransmission for the case of errors. In addition, the proposed MAC synchronizes with AP by using beacon and adopts a hybrid tracking mode that supports economic power consumption according to various traffic situations, We implemented a simulator for the proposed MAC by using sim++ and evaluated various performances. The simulation results show that the proposed MAC reduces the power consumption and reveals excellent performance in real-time application systems.

• Journal of Magnetics
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• v.19 no.3
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• pp.248-254
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• 2014

The purpose of this study is to figure out how uptake counts of technetium ($^{99m}Tc$) among radioisotopes in the human body are affected if computed tomography (CT), magnetic resonance imaging (MRI) and isotope examination are performed consecutively. $^{99m}Tc$ isotope material, iodinated contrast media for CT and paramagnetic contrast media for magnetic resonance (MR) were used as experimental materials. First, $^{99m}Tc$ was added to 4 cc normal saline in a test tube. Then, 2 cc of CT contrast media such as $Iopamidol^{(R)}$ and $Dotarem^{(R)}$ were diluted with 2 cc normal saline, and 2cc of MRI contrast media such as $Primovist^{(R)}$ and $Gadovist^{(R)}$ were diluted with 2 cc normal saline. Each distributed contrast media was a total of 4 cc and included 10m Ci of $^{99m}Tc$. A gamma camera, a LEHR (Low energy high resolution) collimator and a pin-hole collimator were used for image acquisition. Image acquisition was repeated a total of 6 times and 120 frames were obtained and uptake counts of $^{99m}Tc$ were measured (from this procedure). In this study, as a result of measuring the uptake counts of $^{99m}Tc$ using the LEHR collimator, the uptake counts were less measured in all contrast media than normal saline as a reference. In particular, the lowest uptake counts were measured when $Gadovist^{(R)}$, contrast media for MRI, was used. However, the result of measuring the uptake counts of $^{99m}Tc$ using the pin-hole collimator showed higher uptake counts in all contrast media, except for $Iopamidol^{(R)}$, than normal saline as a reference. The highest uptake counts were measured particularly when $Primovist^{(R)}$, contrast media for MRI, was used. In performing the gamma camera examination using contrast media and $^{99m}Tc$, it is considered significant to check the changes in the uptake counts to improve various diagnosis values.

• Korean journal of applied entomology
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• v.17 no.3 s.36
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• pp.155-160
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• 1978

This experiment was carried out to develope a technique for labelling pine gall midge with ·radioactive phosphorus and calcium. This technique evolved would help to obtain basic information on the appropriate concentration of $^{32}P\; and\; ^{45}Ca$ in tagging and determination of adult flight ranges which considered as one of the factors in dissemination. 1. Labelling at the larval stage of pine gall midge by injection of $^{45}Ca$ into pine tree trunk appeared not to be effective for tagging the adults because radioactivity was gradually decreased to background by emergence. 2. The radioactivities of larvae in the galls gradually increased in September but from October 1 the activity was gradually decreased for 10 days then equilibrium was maintained thereafter. The results seem to indicate that larval diet termination occured early October. 3. A maximum level of radiation was detected at 3 weeks after $^{32}P$ injection and thereafter it was gradually reduced. This result implies that $^{32}P$ is not appropriate radioisotope in labelling pine gall midge through trunk injection method. 4. After washing in running water for 10 minutes, the optimum$^{32}P$ concentration for treated overwintered larvae and pupae was found to be 0.5 micro curie per ml. for 30 minutes dipping.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.29 no.4
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• pp.14-23
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• 2016

Objectives : One of major complications of diabetes, diabetic ulcer is also one of the main reasons for amputation, and the prevalence rate is 4-10%. Laser therapy is widely used for leg ulcer and diabetic ulcer, and it is known to improve wound epithelialization, cellular content, and collagen deposition. The purpose of this study is to investigate the properties of the laser and the spectrum of laser instruments for diabetic ulcer. Methods : We performed literature search using the PubMed, Cochrane, CINAHL and Web of science for the data in English. In addition, other databases were checked for different languages such as OASIS and NDSL for the literature in Korean, CNKI in Chinese, and CiNii and J-STAGE written in Japanese. We excluded all review article and experimental studies, and only clinical studies using laser or light emitting diode (LED) for diabetic ulcer were selected. Results : A total twenty papers were selected. Different light sources were used as follows: LED, HeNe, InGaAlP, GaAlAs, GaAs, CO2, and KTP. The number of LED studies was 9, and HeNe laser was 7, and InGaAlP and GaAlAs laser was 2, GaAs, CO2, and KTP laser was 1 for each. Various energy density of the clinical study were reported. Conclusions : It is suggested that to select appropriate laser type and give the adequate output power to treat diabetic ulcer. Further evaluation and research for the condition of laser therapy to treat diabetic ulcers are warranted.

• Economic and Environmental Geology
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• v.34 no.1
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• pp.105-117
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• 2001

The characteristics of hydrogeochemistry and fluorine distribution in drinking groundwater from limestone and granite were studied in the Keumsan-Wanju area, where major important fluorite-deposits are distributed. The hydrochemical properties of groundwater from studied area arc commonly characterized as $Ca-HC0_3$ water type. However, some of the groundwater samples collected from Jurassic and Cretaceuus granites belong to $Ca-Na-HC0_3 and Na-HC0_3$ type, respectively. The contamination of drinking groundwater by minewater from the nearby fluorite deposits is not found yet. However, groundwater having high F contents up to 1].4 mgll, which is higher than the drinking water limit, is found from the wells located in Cretaceous granite. The tluorine contents in groundwater generally increase with increasing well depth. The concentrations of F in the groundwater show a positive relationship with the values of Na, $HC0_3, Cl. Si0_2$, pH, whereas a negative relationship with Ca. The positive correlation of F-concentrations to major elements ($Si0_2$, Na, CI) and trace elements (Li, B, Rb) may suggest that the groundwater come from the decomposition of tluoride-bearing silicate minerals within highly differentiated granitic rocks, Therefore, wells for drinking water should not be developed or should be drilled within shallow level in the Cretaceous granite region to reduce the F contents in the groundwater.