• Korean Journal of Remote Sensing
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• v.31 no.5
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• pp.395-408
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• 2015

High-resolution satellite image mosaics are becoming increasingly important in the field of remote sensing image analysis as an essential image processing to create a large image constructed from several smaller images. In this paper, we present an automatic seamline extraction technique and the procedure to generate a mosaic image by this technique. For more effective seamline extraction in the overlap region of adjacent images, an NDVI-based seamline extraction technique is developed, which takes advantage of the computational time and memory. The Normalized Difference Vegetation Index(NDVI) is an index of plant "greeness" or photosynthetic activity that is employed to extract the initial seamline. The NDVI can divide into manmade region and natural region. The cost image is obtained by the canny edge detector and the buffering technique is used to extract the ranging cost image. The seamline is extracted by applying the Dijkstra algorithm to a cost image generated through the labeling process of the extracted edge information. Histogram matching is also conducted to alleviate radiometric distortion between adjacent images acquired at different time. In the experimental results using the KOMPSAT-2/3 satellite imagery, it is confirmed that the proposed method greatly reduces the visual discontinuity caused by geometric difference of adjacent images and the computation time.

• Journal of Korean Academy of Nursing
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• v.25 no.4
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• pp.751-773
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• 1995

We, clinical nurse specialists practising and guiding student practice in a Community health nursing clinic, wanted to develop a family pattern appraisal consistent with Rogers' conceptual system, the nursing model guiding our practice. We use Rogers' model because it is harmonious with the traditional Korean view of the one human, natural and cosmic world. The purpose of our research was to contribute to science - based nursing practice, not only, one helpful model, but also a model of how to use, in guiding practice, a conceptual system which reflects nurse practitioners' philosophy of nursing, is intellectually satisfying, and enriches meaning in daily nursing life. The research objectives were to review the literature on Rogers' model and analyse it according to Kim's five - level analytical framework, to explore Rogers' definition of family, to review appraisals based on Rogers' model, and to develop a family appraisal which is culturally appropriate for use in our community. This work including the use of the appraisal and its refinement with families in our practice which was done during 1994 and 1995, in Seoul, in the Capital of the Republic of Korea. At the highest level of analysis, Rogers conceptual system emphasizes acausality and multidimentional meaning ; the world view is characterized by process, movement and wholeness. The epistemology Is one of holism and the knowledge base includes all forms of experience, from sensory to mystical, objective, and subjective. At the metaparadigm level, nursing focuses on the unitary human being and the environment. At the level of nursing philosophy, the model identifies human being, nursing, nurse, and illness and health. At the paradigm level the model assumes the irriducibility of the human to parts, noncausality and continual change. Rogers' practice methodology consists of pattern manifestation appraisal and deliberative mutual patterning. Under-standing patterns and patterning of people is the key to helping them achieve their potential. At the theory level, the basic assumptions, key concepts, and homeodynamic principles were identified. Rogers states the family energy field is an undividable, four-dimensional negentropic energy field which is in a larger envircinmental field show-ing such characteristics as cannot be predicted by knowledge of individual family members. Based on the word of Rogers scholars, we chose Rogers' correlates of patterning to understand the family unit as a whole-frequency, rhythms, motion, time perception, sleeping-waking beyond waking, pragmatic -imaginative-visionary to develop the appraisal. We, also used some of Barrel's (1988) criteria including interpersonal network and professional health care access and use, and Cordon's (1982) criteria including self perception - self concept modified to fit the family. Our family Pattern appraisal included 1. Influencirg data, 2. Professional health care access and use, 3. Family self perception-self concept, 4. Family interpersonal network, 5. Sleep-wake-be-yond waking, 6. Pragmatic-imaginary-visionary, 7. Family frequency and rhythm, 8. Family motion, 9. Family time perception. The appraisal was used with four families and modified to eliminate overlap and to make it possible for the family member to express themselves more easily. We plan to gain more experience with the appraisal toward further development of the tool.

• The KIPS Transactions:PartA
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• v.10A no.6
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• pp.665-670
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• 2003

In the applications like automatic masks generation for semiconductor production, a drawing consists of lots of polygons that are partitioned into trapezoids. The addition/deletion of a polygon to/from the drawing is performed through geometric operations such as insertion, deletion, and search of trapezoids. Depending on partitioning algorithm being used, a polygon can be partitioned differently in terms of shape, size, and so on. So, It's necessary to invent some comparison algorithm of sets of trapezoids in which each set represents interested parts of a drawing. This comparison algorithm, for example, may be used to verify a software program handling geometric objects consisted of trapezoids. In this paper, given k sets of trapezoids in which each set forms the regions of interest of each drawing, we present how to compare the k sets to see if all k sets represent the same geometric scene. When each input set has the same number n of trapezoids, the algorithm proposed has O(2$^{k-2}$ $n^2$(log n＋k)) time complexity. It is also shown that the algorithm suggested has the same time complexity O( $n^2$ log n) as the sweeping-based algorithm when the number k(<< n) of input sets is small. Furthermore, the proposed algorithm can be kn times faster than the sweeping-based algorithm when all the trapezoids in the k input sets are almost the same.

• Journal of KIISE:Databases
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• v.33 no.5
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• pp.495-512
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• 2006

Recently, researches on a future position prediction of moving objects have been progressed as the importance of the future position retrieval increases. New index structures are required to efficiently retrieve the consecutive positions of moving objects. Existing index structures significantly degrade the search performance of the moving objects because the search operation makes the unnecessary extension of the node in the index structure. To solve this problem, we propose a space partition based index structure considering the mobility of moving objects. To deal with the overflow of a node, our index structure first merges it and the sibling node. If it is impossible to merge them, our method splits the overflow node in which moving properties of objects are considered. Our index structure is always partitioned into overlap free subregions when a node is split. Our split strategy chooses the split position by considering the parameters such as velocities, the escape time of the objects, and the update time of a node. In the internal node, the split position Is determined from preventing the cascading split of the child node. We perform various experiments to show that our index structure outperforms the existing index structures in terms of retrieval performance. Our experimental results show that our proposed index structure achieves about $17%{\sim}264%$ performance gains on current position retrieval and about $107%{\sim}19l%$ on future position retrieval over the existing methods.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.279.2-279.2
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• 2016

InGaN/GaN multiple quantum wells (MQWs) have been attracted much attention as light-emitting diodes (LEDs) in the visible and UV regions. Particularly, quantum efficiency of green LEDs is decreased dramatically as approaching to the green wavelength (~500 nm). This low efficiency has been explained by quantum confined Stark effect (QCSE) induced by piezoelectric field caused from a large lattice mismatch between InGaN and GaN. To improve the quantum efficiency of green LED, several ways including epitaxial lateral overgrowth that reduces differences of lattice constant between GaN and sapphire substrates, and non-polar method that uses non- or semi-polar substrates to reduce QCSE were proposed. In this study, graded short-period InGaN/GaN superlattice (GSL) was grown below the 5-period InGaN/GaN MQWs. InGaN/GaN MQWs were grown on the patterned sapphire substrates by vertical-metal-organic chemical-vapor deposition system. Five-period InGaN/GaN MQWs without GSL structure (C-LED) were also grown to compare with an InGaN/GaN GSL sample. The luminescence properties of green InGaN/GaN LEDs have been investigated by using photoluminescence (PL) and time-resolved PL (TRPL) measurements. The PL intensities of the GSL sample measured at 10 and 300 K increase about 1.2 and 2 times, respectively, compared to those of the C-LED sample. Furthermore, the PL decay of the GSL sample measured at 10 and 300 K becomes faster and slower than that of the C-LED sample, respectively. By inserting the GSL structures, the difference of lattice constant between GaN and sapphire substrates is reduced, resulting that the overlap between electron and hole wave functions is increased due to the reduced piezoelectric field and the reduction in dislocation density. As a results, the GSL sample exhibits the increased PL intensity and faster PL decay compared with those for the C-LED sample. These PL and TRPL results indicate that the green emission of InGaN/GaN LEDs can be improved by inserting the GSL structures.

• Korean Journal of Remote Sensing
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• v.34 no.6_1
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• pp.1143-1153
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• 2018

For TOPS InSAR processing, high-precision image co-registration is required. We propose an image co-registration method suitable for the TOPS mode by comparing the performance of cross correlation method, the geometric co-registration and the enhanced spectral diversity (ESD) matching algorithm based on the spectral diversity (SD) on the Sentinel-1 TOPS mode image. Using 23 pairs of interferometric pairs generated from 25 Sentinel-1 TOPS images, we applied the cross correlation (CC), geometric correction with only orbit information (GC1), geometric correction combined with iterative cross-correlation (GC2, GC3, GC4), and ESD iteration (ESD_GC, ESD_1, ESD_2). The mean of co-registration errors in azimuth direction by cross correlation and geometric matching are 0.0041 pixels and 0.0016 pixels, respectively. Although the ESD method shows the most accurate result with the error of less than 0.0005 pixels, the error of geometric co-registration is reduced to 0.001 pixels by repetition through additional cross correlation matching between the reference and resampled slave image. The ESD method is not applicable when the coherence of the burst overlap areas is low. Therefore, the geometric co-registration method through iterative processing is a suitable alternative for time series analysis using multiple SAR data or generating interferogram with long time intervals.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.2
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• pp.265-272
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• 2007

This proposed gamma (${\gamma}$) correction system is developed to reduce the difference between non-linear gamma curve produced by a typical formula and result produced by the proposed algorithm. In order to reduce the difference, the proposed system is using the Least Squares Polynomial which is calculating the best fitting polynomial through a set of points which is sampled. Each system is consisting of continuous several kinds of equations and having their own overlap sections to get more precise. Based on the algorithm verified by MATLAB, the proposed systems are implemented by using Verilog-HDL. This paper will compare the previous algorithm of gamma system such as Existing system with Seed Table with the latest that such as Proposed system. The former and the latter system have 1, 2 clock latency; each 1 result per clock. Because each of the error range (LSB) is $1{\sim}+1,\;0{\sim}+36$, we can how that Proposed system is improved. Under the condition of SAMSUNG STD90 0.35 worst case, each gate count is 2,063, 2,564 gates and each maximum data arrival time is 29.05[ns], 17.52[ns], respectively.

• Journal of Biomedical Engineering Research
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• v.23 no.1
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• pp.49-60
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• 2002

Receive dynamic focusing with an array transducer can provide near optimum resolution only in the vicinity of transmit focal depth. A customary method to increase the depth of field is to combine several beams with different focal depths, with an accompanying decrease in the frame rate. In this Paper. we Present a simultaneous multiple transmit focusing method in which chirp signals focused at different depths are transmitted at the same time. These chirp signals are mutually orthogonal in a sense that the autocorrelation function of each signal has a narrow mainlobe width and low sidelobe levels. and the crossorelation function of any Pair of the signals has values smaller than the sidelobe levels of each autocorrelation function. This means that each chirp signal can be separated from the combined received signals and compressed into a short pulse. which is then individually focused on a separate receive beamformer. Next. the individually focused beams are combined to form a frame of image. Theoretically, any two chirp signals defined over two nonoverlapped frequency bands are mutually orthogonal In the present work. however, a tractional overlap of adjacent frequency bands is permitted to design more chirp signals within a given transducer bandwidth. The elevation of the rosscorrelation values due to the frequency overlap could be reduced by alternating the direction of frequency sweep of the adjacent chirp signals We also observe that the Proposed method provides better images when the low frequency chirp is focused at a near Point and the high frequency chirp at a far point along the depth. better lateral resolution is obtained at the far field with reasonable SNR due to the SNR gain in Pulse compression Imaging .

• (The) Research of the performance art and culture
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• no.39
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• pp.279-323
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• 2019

The musical characteristics of Fishing songs in North Korean which recorded on Anthology of North Korean Folk Songs were examined in this paper. The results are as follows. Among Fishing songs in North Korea, there are "Rowing Song," the "Song for Hauling Nets," and the "Song for Picking Up Fish" in songs related to walleye pollack fishing and in songs related to croaker fishing, the "Song for Dropping Anchor" and the "Full-Load-of-Fish Song" in songs related to croaker fishing, the "Song for Weighing Anchor," the "Song for Shaking Fish," the "Full-Load-of-Fish Rowing Song," and the "Song for Hanging Walleye Pollack" in songs related to walleye pollack fishing. There are the "Song for Setting a sail" and the "Song for catching shells" in Fishing songs in North Korea, too. In the rhythmic elements of Fishing songs in North Korea, the tempo of the "Songs for Setting a sail" is moderato, and that of the "Songs for Picking Up Fish" of songs related to anchovy or herring fishing is quite slow. "Rowing Songs"(croaker fishing) have various tempos but faster than moderato, and usually get faster and faster as time goes by. Most songs have 4/♩. time and there are some of 2, 3 or 5 time. Some songs use irregular time or 6 time overlapping 2 beats. The mode Menari is the most common tonal system used in fishing songs of North Korea. And the mode Susimga, the mode Changbutaryeong, the mode Nanbongga, and the mode Odolttogi are also used in the tonal system of Fishing songs in North Korea. There are shoutting intonations that have indefinite pitch, too. Modulation or interaction by the mode Changbutaryeong appeared in songs of the mode Menari. There is a tendency to favor a certain tonal system by category. Responsorial form is mostly used, but in the most cases, they were sung in solo. In responsorial songs, several calling songs overlap with the responding songs. Durchkomponiert form is sung by antiphon or in solo, but the case sung in solo originally seems to have been sung by antiphon or unison, if we consider the procedure of the work. The "Song for Picking Up Fish" of Seonbong-gun of North Hamgyeong Province and Yangyang-gun of Gangwon Province, the "Full-Load-of-Fish Song-Bongjuktaryeong" of Jeungsan-gun of South Pyeongan Province and "Full-Load-of-Fish Song-Baechigisory" of Taean-gun of South Chungcheong Province, "Rowing Song" of Nampo City and Ganghwa-gun of Gyeonggi Province are resembled. In neighboring areas, even if the songs of different categorys, sometimes share a same melody. In a certain category, sometimes a same melody is shared to a considerable distance. It was first identified that in anchovy or herring fishing or dybowskii' sand eel fishing, the "Song for Picking Up Fish" is widely shared in the East Sea Coast area.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.1
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• pp.31-43
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• 2015

Purpose : Stereotactic body radiation therapy (SBRT) has proved its efficacy in several patient populations with primary and metastatic limited tumors. Because SBRT prescription is high dose level than Conventional radiation therapy. SBRT plan is necessary for effective Organ at risk (OAR) protection and sufficient Planning target volume (PTV) dose coverage. In particular, multi-target cases may result excessive doses to OAR and hot spot due to dose overlap. This study evaluate usefulness of Volumetric modulated arc therapy (VMAT) in dosimetric and technical considerations using Flattening filter free (FFF) beam. Materials and Methods : The treatment plans for five patients, being treated on TrueBeam STx(Varian$^{TM}$, USA) with VMAT using 10MV FFF beam and Standard conformal radiotherapy (CRT) using 15MV Flattening filter (FF) beam. PTV, liver, duodenum, bowel, spinal cord, esophagus, stomach dose were evaluated using the dose volume histogram(DVH). Conformity index(CI), homogeneity index(HI), Paddick's index(PCI) for the PTV was assessed. Total Monitor unit (MU) and beam on time was assessed. Results : Average value of CI, HI and PCI for PTV was $1.381{\pm}0.028$, $1.096{\pm}0.016$, $0.944{\pm}0.473$ in VMAT and $1.381{\pm}0.042$, $1.136{\pm}0.042$, $1.534{\pm}0.465$ in CRT respectively. OAR dose in CRT plans evaluated 1.8 times higher than VMAT. Total MU in VMAT evaluated 1.3 times increase than CRT. Average beam on time was 6.8 minute in VMAT and 21.3 minute in CRT. Conclusion : VMAT for SBRT in multi-target liver cancer using FFF beam is effective treatment techniqe in dosimetric and technical considerations. VMAT decrease intra-fraction error due to treatment time shortening using high dose rate of FFF beam.