• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.11 s.102
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• pp.1147-1154
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• 2005

In this paper, we propose some PAPR(Peak to Average Power Ratio) reduction methods using WHT(Walsh Hadamard Transform) to reduce high PAPR generated in OFDM system because of multi carrier modulation. These proposed methods are the methods which has additional PAPR reduction performance without a loss of bandwidth efficiency and a large increment of calculation complexity than common PAPR reduction methods by combining the WHT with some common methods. In this paper, we propose two PAPR reduction methods made by combining a SLM(Selective Mapping) and DSI(Dummy Sequence Insertion) with a WHT. From simulation result, we can find that the PAPR reduction methods using a WHT can get about 1 dB additional PAPR reduction performance than common PAPR reduction methods; they are SLM and DSI. And, because our proposed methods have not only PAPR reduction effect, but also frequency diversity effect, more stabile data transmission is possible in nonlinear HPA and multipath fading channel.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.3
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• pp.109-122
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• 2020

In recent, projection mapping, which has attracted high attention in the field of realistic media, is regarded as a technology to increase the users' immersion. However, most existing methods perform projection mapping on static objects. In this paper, we developed a technology to track the movements of users and dynamically map the media contents to the users' bodies. The projected media content is built by predefined gestures just using the user's bare hands without the special devices. An interactive immersive media system has been implemented by integrating these dynamic projection mapping technologies and gesture-based drawing technologies. The proposed realistic media system recognizes the movements and open / closed states of the user 's hands, selects the functions necessary to draw a picture. The users can freely draw the picture by changing the color of the brush using the colors of any real objects. In addition, the user's drawing is dynamically projected on the user's body, allowing the user to design and wear his t-shirt in real-time.

• Korean Journal of Head & Neck Oncology
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• v.23 no.1
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• pp.37-40
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• 2007

Objectives：Cutaneous angiosarcoma is an infrequent but aggressive neoplasm involving the skin of the face and scalp. Unfamiliarity with the clinical manifestations of cutaneous angiosarcoma frequently leads to misdiagnosis and delay in treatment. Complete surgical resection requires the performance of preoperative staging biopsies to determine the true extent of the neoplasm. Intraoperative frozen section analysis to determine the adequacy of the surgical resection is unreliable due to the high false negative rate. Material and Methods：In five scalp angiosarcoma cases, mapping biopsies were performed at far from the suspected edge of the neoplasm. On permanent pathology, we obtained tumor free margin with occasional focal involvement of the tumor. Results：Frozen-section analysis of the resected margins is inconclusive, for the subtle diagnostic features of angiosarcoma are distorted by the tissue processing required for frozen-section analysis. The characteristic dermal vessels lined by their malignant cells are collapsed by the freezing process. This results in a high rate of false-negative reports and possibly leads to incomplete resection of the neoplasm. Conclusion：Our recommendation is to establish the margins of the tumor by performing preoperative evaluations by mapping biopsies.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.5
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• pp.479-485
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• 2011

A number of case studies that find distribution of longevity population and influencing factors through the spatial data fusion using GIS techniques are growing. The majority cases of these studies are adopt census administrative boundary data for the spatial analysis. However, these methods cannot fully explain the phenomenon of longevity because there are a variety of spatial characteristics within the census administrative boundaries. Therefore, studies of spatial unit are required that realistically reflect the phenomenon of human longevity. The dasymetric mapping method enables to product of spatial unit more realistic than census administrative boundary map and statistic estimates of small area utilizing diversity spatial information. In this study, elderly population of small area has been estimated within statistically significant level that applied the vector based dasymetric mapping method. Also, the cluster analysis confirmed that the variation of local spatial relationship within census administrative boundary. The result of this study implied that the need for local-level studies of the human longevity and the validity of the dashmetric mapping techniques.

• Journal of Biosystems Engineering
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• v.27 no.3
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• pp.259-266
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• 2002

It is crucial to know spatial soil variability for precision farming. However, it is time-consuming, and difficult to measure spatial soil properties. Therefore, there are needs fur sensing technology to estimate spatial soil variability, and for electronic mapping technology to store, manipulate and process the sampled data. This research was conducted to develop a real-time soil organic matter sensor and an electronic mapping system. A soil organic matter sensor was developed with a spectrophotometer in the 900∼1,700 nm range. It was designed in a penetrator type to measure reflectance of soil at 15cm depth. The signal was calibrated with organic matter content (OMC) of the soil which was sampled in the field. The OMC was measured by the Walkeley-Black method. The soil OMCs were ranged from 0.07 to 7.96%. Statistical partial least square and principle component regression analyses were used as calibration methods. Coefficient of determination, standard error prediction and bias were 0.85 0.72 and -0.13, respectively. The electronic mapping system was consisted of the soil OMC sensor, a DGPS, a database and a makeshift vehicle. An algorithm was developed to acquire data on sampling position and its OMC and to store the data in the database. Fifty samples in fields were taken to make an N-fertilizer dosage map. Mean absolute error of these data was 0.59. The Kring method was used to interpolate data between sampling nodes. The interpolated data was used to make a soil OMC map. Also an N-fertilizer dosage map was drawn using the soil OMC map. The N-fertilizer dosage was determined by the fertilizing equation recommended by National Institute of Agricultural Science and Technology in Korea. Use of the N-fertilizer dosage map would increase precision fertilization up to 91% compared with conventional fertilization. Therefore, the developed electronic mapping system was feasible to not only precision determination of N-fertilizer dosage, but also reduction of environmental pollution.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.1
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• pp.56-63
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• 2007

A color gamut mapping has been known to be one of promising methods to enhance display quality of various types of color display device. However, it is required to handle this mapping in real time for display or digital TV application. If carefully arranged, the tetrahedral interpolation can be computed with simpler operations compared to a cubic interpolation in the conventional reduced resolution look-up table which is devised to process the gamut mapping in real time. Based on the tetrahedral interpolation, a new type hardware architecture for real-time gamut mapping is proposed in this paper. The proposed hardware architecture shows better processing speed and reduces the hardware cost.

• Korean Journal of Health Education and Promotion
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• v.29 no.5
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• pp.125-133
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• 2012

Objectives: We used participatory mapping as a tool for empowerment training for promoting health and safety of farmers. We would like to introduce the application of participatory mapping method and report our experiences in a rural community in Korea. Methods: A one-day workshop was offered in six rural villages which were designated as 'safe farm zones'. Each workshop started with an orientation session, followed by a village rounding, presentations of best cases, a group exercise to draw and present a healthy village map. Participants were requested to express their ideas and experiences about healthy and safe residential and working environments on their map. Results: A total of 206 farmers(100 male, 106 female) participated in the workshops. In each workshop, an average of 34.3 farmers participated, and their mean age was 59 years. In the six workshops, the participants proposed a total of 137 action plans. The action plans included improvement of co-working condition, building facilities for recreation, improving traffic safety measures, and improving residential environment. Conclusions: Participatory mapping was successfully developed and applied as a tool for empowering Korean farmers. The participants were able to express their ideas and thoughts about healthy and safe village and action plans on the map. Moreover, some of the actions in the action plans were carried out immediately after workshop.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.1
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• pp.38-50
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• 1999

Currently many devices reproduce electronic images in the various ways. However the color that is reproduced in any device is different from the original color due to the difference in the gamut between devices. In this paper, an image dependent gamut mapping method is proposed. This method clips the chroma with compensating for the change of lightness caused by the lightness scaling. The anchor point, which is the center point in the mapping, is set as a lower point by the proposed method than a point by the conventional mapping method. This reduces the color difference between point. In addition, to heighten the color contrast on the constant hue, the different two mapping methods are applied to the printer gamut which is divided in two region, bright region and dark region. Consequently, the printer output image was highly consistent with the corresponding monitor image.

• Journal of Cardiovascular Imaging
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• v.31 no.2
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• pp.71-82
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• 2023

BACKGROUND: Cardiac magnetic resonance fingerprinting (cMRF) enables simultaneous mapping of myocardial T1 and T2 with very short acquisition times. Breathing maneuvers have been utilized as a vasoactive stress test to dynamically characterize myocardial tissue in vivo. We tested the feasibility of sequential, rapid cMRF acquisitions during breathing maneuvers to quantify myocardial T1 and T2 changes. METHODS: We measured T1 and T2 values using conventional T1 and T2-mapping techniques (modified look locker inversion [MOLLI] and T2-prepared balanced-steady state free precession), and a 15 heartbeat (15-hb) and rapid 5-hb cMRF sequence in a phantom and in 9 healthy volunteers. The cMRF_5-hb sequence was also used to dynamically assess T1 and T2 changes over the course of a vasoactive combined breathing maneuver. RESULTS: In healthy volunteers, the mean myocardial T1 of the different mapping methodologies were: MOLLI 1,224 ± 81 ms, cMRF_15-hb 1,359 ± 97 ms, and cMRF_5-hb 1,357 ± 76 ms. The mean myocardial T2 measured with the conventional mapping technique was 41.7 ± 6.7 ms, while for cMRF_15-hb 29.6 ± 5.8 ms and cMRF_5-hb 30.5 ± 5.8 ms. T2 was reduced with vasoconstriction (post-hyperventilation compared to a baseline resting state) (30.15 ± 1.53 ms vs. 27.99 ± 2.07 ms, p = 0.02), while T1 did not change with hyperventilation. During the vasodilatory breath-hold, no significant change of myocardial T1 and T2 was observed. CONCLUSIONS: cMRF_5-hb enables simultaneous mapping of myocardial T1 and T2, and may be used to track dynamic changes of myocardial T1 and T2 during vasoactive combined breathing maneuvers.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.1
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• pp.99-113
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• 2004

A new architecture called SAN(Storage Area Network) was developed in response to the requirements of high availability of data, scalable growth, and system performance. In order to use SAN more efficiently, most of SAN operating softwares support storage virtualization concepts that allow users to view physical storage devices attached to SAN as a large volume virtually h logical volume manager plays a key role in storage virtualization. It realizes the storage virtualization by mapping logical addresses to physical addresses. A logical volume manager also supports a snapshot that preserves a volume image at certain time and on-line reorganization to allow users to add/remove storage devices to/from SAN even while the system is running. To support the snapshot and the on-line reorganization, most logical volume managers have used table based mapping methods. However, it is very difficult to manage mapping table because the mapping table is large in proportion to a storage capacity. In this paper, we design and implement an efficient and flexible hybrid mapping method based on mathematical equations. The mapping method in this paper supports a snapshot and on-line reorganization. The proposed snapshot and on-line reorganization are performed on the reserved area which is separated from data area of a volume. Due to this strategy normal I/O operations are not affected by snapshot and reorganization. Finally, we show the superiority of our proposed mapping method through various experiments.