• Korean Journal of Remote Sensing
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• v.27 no.2
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• pp.171-180
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• 2011

MAI (multiple aperture SAR interferometry) method has been recently developed to improve the measurement accuracy of along-track surface deformation. By means of split-beam SAR processing, this novel technique produces forward- and backward-looking interferograms, which are combined to generate an MAI interferogram. The along-track surface deformation can then be derived from the MAI interferogram. The achieved accuracy of the along-track surface deformation is approximately 8 cm for interferograms with a coherence of 0.6. It is commonly recognized that the topographic phase on an MAI interferogram can be ignored. However, in this paper, we have generated an MAI interferogram from an ALOS P ALSAR interferometric pair spanning the 2010 Haiti earthquake, and shown that the topographic phase distortion on the MAI interferogram can reach to about $3.45{\times}10^{-4}$ rad./m. This distortion corresponds to an along-track surface deformation of about 98 cm. We have proposed an efficient method to remove the topographic phase distortion. After correcting the distortion, the topographic phase distortion on the MAI interferogram is reduced to about $7.82{\times}10^{-6}$ rad./m. This means that the proposed method can effectively remove the topographic distortion on the MAI interferogram to improve along-track surface deformation measurement.

• Korean Journal of Remote Sensing
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• v.27 no.2
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• pp.121-130
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• 2011

This paper highlights the reconstruction of the rectilinear type of 3D rooftop model from satellite image data using centroid neural network. The main idea of the proposed 3D reconstruction method is based on the grouping of 3D line segments. 3D lines are extracted by 2D lines and DEM (Digital Elevation Map) data evaluated from a pair of stereo images. Our grouping process consists of two steps. We carry out the first grouping process to group fragmented or duplicated 3D lines into the principal 3D lines, which can be used to construct the rooftop model, and construct the groups of lines that are parallel each other in the second step. From the grouping result, 3D rooftop models are reconstructed by the final clustering process. High-resolution IKONOS images are utilized for the experiments. The experimental result's indicate that the reconstructed building models almost reflect the actual position and shape of buildings in a precise manner, and that the proposed approach can be efficiently applied to building reconstruction problem from high-resolution satellite images of an urban area.

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.121-128
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• 2012

High resolution intertidal DEM is a basic material for science research like sedimentation/erosion by ocean current, and is invaluable in a monitoring of environmental changes and practical management of coastal wetland. Since the intertidal zone changes rapidly by the inflow of fluvial debris and tide condition, remote sensing is an effective tool for observing large areas in short time. Although radar interferometry is one of the well-known techniques for generating high resolution DEM, conventional repeat-pass interferometry has difficulty on acquiring enough coherence over tidal flat due to the limited exposure time and the rapid changes in surface condition. In order to overcome these constraints, we tested the feasibility of radar interferometry using Cosmo-SkyMed tandem-like one-day data and ERS-ENVISAT cross tandem data with very short revisit period compared to the conventional repeat pass data. Small temporal baseline combined with long perpendicular baseline allowed high coherence over most of the exposed tidal flat surface in both observations. However the interferometric phases acquired from Cosmo-SkyMed data suffer from atmospheric delay and changes in soil moisture contents. The ERS-ENVISAT pair, on the other hand, provides nice phase which agree well with the real topography, because the atmospheric effect in 30-minute gap is almost same to both images so that they are cancelled out in the interferometric process. Thus, the cross interferometry with very small temporal baseline and large perpendicular baseline is one of the most reliable solutions for the intertidal DEM construction which requires very accurate mapping of the elevation.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.85-95
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• 1984

This study was performed to investigate the intestinal parasites (especially cestoda) in the guts of Theragra chalcogramma in Korea. The cestode larvae collected were morphologically observed and measured, and at the same time, microscopical study was done with the section slides of the cestode larvae. They were identified on the basis of the descriptions by Schmidt and Yamaguti. The results obtained in this study are as follows: 1. The cestode larvae were identified as Khawia sinesis, Eulacistorhynchus chiloscyllius, Tentacularia coryphaenga, Pssudonybelinia odontasantha and Nybelinia Zingualis. These are new species reported in Korea. 2. The characteristics of Khawia sinesis are its scolex lacking loculi and broad, fat and fimbriate shape. Its neck is not separated from the body but a little constricted. 3. Eulacistorhynchus chiloscyzzius is characterized by fairly long and acraspedote scolex. The bulbs are long; retractor muscles are attached to bases of the bulbs. The two bothridia are oval or round in shape and lacking posterior notch. The tentacles are long and poeciloacanthus; double chainette present. 4. Tentacularia coryphaenea is characterized by its long craspedote and subcylindrical scolex. The bothridia are separated, without free borders and spinous. The tentacles are short, slender, armed with solid hooks in spirals, similar except the base of tentacle. The tentacle sheaths are not twisted. The bulbs are ellipsoidal. 5. Pseudonybelinia odontacantha is characterized by its craspedote scolex. The tentacles are inserted near anterior margin of bothridia and armed with hooks in spirals ascending left to right. The hooks are similar, throughout tentacle, with feeble curve and provided with a tooth-like protuberance on the ventral side. The bulbs are three times longer than its width. The posterior margins of bothridia have a pair of eversible ciliated pits; or fossettes. 6. Nybelinia lingualis is characterized by its short and craspedote scolex. The bothridia are separated, with free boarders. The tentacles are cylindrical, armed with solid and similar hooks in quincunxes.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.17 no.1
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• pp.47-51
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• 2014

Purpose: Neonatal late-onset hypocalcemia is defined as hypocalcemia developed after postnatal 3 days and associated with hypoparathyroidism, high phosphate diets and vitamin D deficiency. We experienced the increment of neonatal late onset hypocalcemia over 1 year. We tried to evaluate the relationship between late onset hypocalcemia and maternal hypovitaminosis D. Methods: The medical records in the neonates with late-onset hypocalcemia during January 2007 to July 2008 were retrospectively reviewed. Among those patients, 17 paired sera of mothers and neonates had collected. The levels of 25-OH vitamin D (25OHD) and intact parathyroid hormone (iPTH) were measured and were compared with neonate and the mother. Results: The mean gestational age was $38^{+1}$ weeks, and the mean body weight was 2,980 g. The onset time of hypocalcemia was 5.9 days of age. Most of them (88.2%) were feeding with formula and no one was only breast milk feeding. Of the 17 patients, 13 were born in spring or in winter. The median levels of calcium, phosphorus, alkaline phosphatase, iPTH and 25OHD were 7.0 mg/dL, 8.6 mg/dL, 191.0 U/L, 57.2 pg/mL and 24.0 ng/mL in neonates. The levels of 25OHD of 6 neonates were <20 ng/mL. A total of 16 mothers were considered vitamin D-deficient (<20 ng/mL), and vitamin D insufficient (20<25OHD<30 ng/mL). Conclusion: Neonatal late-onset hypocalcemia in our study seems to be influenced by maternal vitamin D deficiency and insufficiency. Sun tanning and vitamin D supplements from winter to spring would be helpful to prevent maternal vitamin D deficiency, one of the causes of neonatal late-onset hypocalcemia.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.2
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• pp.105-114
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• 2007

Two-dimensional imaging of $V_s$ profile becomes more important in Korea because of the large horizontal variation of soil stiffness. To obtain a shear-wave velocity profile in geotechnical practice, various seismic nondestructive investigation methods are being frequently used. In this study, harmonic wavelet analysis of wave (HWAW) method is applied to the determination of $V_s$ profile to overcome some of weaknesses in the existing surface wave methods. HWAW method which is based on time-frequency analysis using harmonic wavelet transform has been developed to determine phase and group velocities of waves. Field testing of this method is relatively simple and fast because one experimental setup which consists of one pair of receivers is needed to determine $V_s$ profile of site. The proposed method uses the signal portion of the maximum local signal/noise ratio to evaluate the phase velocity to minimize the effects of noise, and uses single array inversion which considers receiver locations. Field tests were performed in 2 sites in order to evaluate accuracy of test method and estimate the applicability of 2-D imaging by HWAW method. Through field applications and comparison with other test results, the good accuracy and applicability of the proposed method were verified.

• Radiation Oncology Journal
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• v.12 no.3
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• pp.307-313
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• 1994

Purpose : Maxillary sinus cancers usually are locally advanced and involve the structures around sinus. It is uncommon for this cancer to spread to the regional lymph-nodes. For this reason, local control is of paramount important for cure. A policy of combined treatment is generally accepted as the most effective means of enhancing cure rartes. This paper reports our experience of a retrospective study of 31 Patients treated with radiation therapy alone and combination therapy of surgery and radiation. Materials and Methods: Between July 1974 and January 1992, 47 Patients with maxillary sinus cancers underwent either radiation therpay alone or combination therapy of surgery and radiation. Of these, only 31 patients were eligible for analysis. The distribution of clinical stage by the AJCC system was $26\%$(8/31) for T2 and $74\%$(23/31) for T3 and T4. Eight patients had palpable lymphadenopathy at diagnosis. Primary site was treated by Cobalt-60 radiation therapy using through a $45^{\circ}$ wedge-pair technique. Elective neck irradiation was not routinely given. Of these 8 patients, the six who had clinically involved nodes were treated with definite radiation therapy. The other two patients had received radical neck dissection. The twenty-two patients were treated with radiation alone and 9 patients were treated with combination radiation therapy, The RT alone patients with RT dose less than 60 Gy were 9 and those above 60 Gy were 13. Results : The overall 5 year survival rate was $23.8\%$. The 5 year survival rate by T-stage was $60.5\%$ and $7.9\%$ for T2 and T3,4, respectively. Statistical significance was found by T-stage(p<0.005). The 5 year survival rate by N-stage was $30\%$ for N (-) and $8.3\%$ for N(+), but statistically no significant difference was seen(p${\geq}$0.1). The 5 year survival rate for RT alone and combination RT was $22.5\%$ and $27.4\%$, respectively. The primary local control rate was $65\%$ (20/31). Conclusion : This study did not show significant difference in survival between RT alone and combination RT. There is still much controversy with regard to which treatment is optimum. Improved RT technique and development of multimodality treatment are essential to improve the local control and the survival rate in patients with advanced maxillary sinus cancer.

• Journal of the Korean Vacuum Society
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• v.20 no.1
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• pp.22-29
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• 2011

An infrared thermographic imaging module of [$320{\times}256$] focal-plane array (FPA) based on [InAs/GaSb] strained-layer superlattice (SLS) was fabricated, and its images were demonstrated. The p-i-n device consisted of an active layer (i) of 300-period [13/7]-ML [InAs/GaSb]-SLS and a pair of p/n-electrodes of (60/115)-period [InAs:(Be/Si)/GaSb]-SLS. FTIR photoresponse spectra taken from a test device revealed that the peak wavelength (${\lambda}_p$) and the cutoff wavelength (${\lambda}_{co}$) were approximately $3.1/2.7{\mu}m$ and $3.8{\mu}m$, respectively, and it was confirmed that the device was operated up to a temperature of 180 K. The $30/24-{\mu}m$ design rule was applied to single pixel pitch/mesa, and a standard photolithography was introduced for [$320{\times}256$]-FPA fabrication. An FPA-ROIC thermographic module was accomplished by using a $18/10-{\mu}m$ In-bump/UBM process and a flip-chip bonding technique, and the thermographic image was demonstrated by utilizing a mid-infrared camera and an image processor.

• Journal of Korea Water Resources Association
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• v.38 no.10 s.159
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• pp.841-849
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• 2005

Two-phase flows, e.g. sediment-laden flow and bubbly flow, have two different flow profiles; flow velocity and sediment velocity. To measure velocity distributions of two-phase flows, it is necessary to use sophisticated instruments which can separate velocity profiles of two-phases. For bubbly flows, PIV (Particle Image Velocimetry) or PTV (Particle Tracking Velocimetry) has given fairly good velocity profiles of two-phases. However, for sediment-laden flows, the applications of PIV or PTV has not been so successful, because the sediment particles introduced to the flow kept the images from being analyzed. A new algorithm, which consists of several image analysis methods, is proposed to analyze sediment-laden flows. For detection algorithm, threshold method, edge detection method, and thinning method are adapted, and for finding matching pair PIV and PTV routines are combined. The proposed method can (1) detect sediment particles with irregular boundaries, (2) remove reflected images and scattered images, and (3) discriminate tracer particles from reflected images of sediment particles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.3
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• pp.259-268
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• 2006

Miniature inverted transposable elements (MITEs) are abundant genomic components in plant including rice. MITE-transposon display (MITE-TD) is an Amplified Fragment Length Polymorphism (AFLP)-related technique based on MITE sequence. In this study, we used the MITE-AFLP for the analysis of diversity and relation-ship of the 114 japonica accessions. Of the several MITEs, the mPing family was applied to detect polymorphisms based on PCR amplification. The BfaI adaptor primer and the specific primer derived from mPing terminal inverted repeat (TIR) region were used to PCR amplification of 114 accessions. Nine primer pairs produced a total of 160 polymorphic bands. PIC values of the polymorphic bands generated by nine primer pairs ranged from 0.269 (BfaI + ACT) to 0.426 (BfaI + T). Each accession revealed a distinct fingerprint with two primer combinations, BfaI + G and BfaI + C. Cluster analysis using marker-based genetic similarity classified 114 accessions into five groups. MITE-AFLP markers were genetically mapped using a population of 80 BILs (BC1F7) derived from a cross between the rice accessions, Milyang 23 and Hapcheonaengmi 3. Eight of the markers produced with the primer pair BfaI + 0 were mapped on chromosomes 1, 2, 4, 5, 7, and 9. Considering that one MITE-AFLP marker on chromosome 7 was tightly linked to the Rc gene, the MITE-AFLP markers will be useful for gene tagging and molecular cloning.