• Korean Journal of Remote Sensing
• /
• v.34 no.6_3
• /
• pp.1427-1443
• /
• 2018

Object-based image analysis (OBIA) allows higher computation efficiency and usability of information inherent in the image, as it reduces the complexity of the image while maintaining the image properties. Superpixel methods oversegment the image with a smaller image unit than an ordinary object segment and well preserve the edges of the image. SLIC (Simple linear iterative clustering) is known for outperforming the previous superpixel methods with high image segmentation quality. Although the input parameter for SLIC, number of superpixels has considerable influence on image segmentation results, impact analysis for SLIC parameter has not been investigated enough. In this study, we performed optimal parameter analysis and evaluation of change detection for SLIC-based superpixel techniques using KOMPSAT data. Forsuperpixel generation, three superpixel methods (SLIC; SLIC0, zero parameter version of SLIC; SNIC, simple non-iterative clustering) were used with superpixel sizes in ranges of $5{\times}5$ (pixels) to $50{\times}50$ (pixels). Then, the image segmentation results were analyzed for how well they preserve the edges of the change detection reference data. Based on the optimal parameter analysis, image segmentation boundaries were obtained from difference image of the bi-temporal images. Then, DBSCAN (Density-based spatial clustering of applications with noise) was applied to cluster the superpixels to a certain size of objects for change detection. The changes of features were detected for each superpixel and compared with reference data for evaluation. From the change detection results, it proved that better change detection can be achieved even with bigger superpixel size if the superpixels were generated with high regularity of size and shape.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.32 no.5
• /
• pp.422-430
• /
• 2010

Purpose: The aim of this study is that we evaluate the change of the White Blood Cell(WBC) count, Absolute Neutrophil Count (ANC), Erythrocyte Sedimentation Rate (ESR) and C-reactive Protein (CRP) values, and try to make standardization for postoperative sequels before and after the oral cancer resection and reconstructive surgery. Materials and Methods: The study was comprised of 34 patients (male 15, female 19) who were diagnosed as an oral cancer and had performed ablation and reconstructive surgery at Dankook university dental hos-pital. Each blood specimen was collected from patients and estimated WBC count, Neutrophil count, ESR, CRP on first, third, fifth, seventh day efore and after surgery and analyzing inter relationship between each value. Classifying Group I (resection with reconstructive surgery patients) and Group II (resection without reconstructive surgery patients). Also classifying group A (below 4 hours of operation time), Group B (4 to 8 hours of operation time), Group C (above 8 hours of operation time), each group was analyzed and compared. The Following results were induced. Results: (1) In coefficient of correlation, the CRP and WBC has highest value except WBC count and Neutrophil count. (2) There was no significant difference any lapse in the progress between Group I and II of WBC count, Neutrophil count, but the CRP shows statistically higher level in group I than group II at immediate postoperative day, and 1 to 5 days after surgery. (3) There is no significant difference any lapse in the progress between Group A, B, C of WBC count, Neutrophil count, but CRP shows statistically significant difference in 1 day, 3 days after surgery Conclusion: It should be suggested that, determination of CRP is most valuable parameter for postopera-tive management and determination of postoperative clinical changes than other parameter such as WBC count, neutrophil count, and ESR values in oral cancer patient after resection and reconstructive surgery, based on the results of this study.

• Journal of Life Science
• /
• v.11 no.2
• /
• pp.126-132
• /
• 2001

Effect of Quartz porphyty(QP) on functional and morphological changes of the liver and kidney was studied in male common finch and white java sparrow fed with the basal diet(Control group) or experimental diet containing 3.0% QP(QP group) for 14 days. There was not significantly different morphological change of the liver upon light microscopic examination in common finch and white java sparrow between control group and QP group. Morphological change of renal tissue upon light microscopic examination in common finch and white java sparrow was not also significantly different between control group and QP group. The concentrations of serum creatinine, blood urea nitrogen, and nric acid as renal functional parameters of common finch and white java sparrow were not significantly different in the both groups. The activity of glutamic oxaloacetic transaminase(GOT) as hepatic functional parameter in common finch was significantly higher in the QP group($\rho$<0.05), whereas the activity of glutamic pyruvic transaminase(GPT) as hepatic functional parameter in common finch was not significantly different in the both groups. The activities of GOP and GPT in white java sparrow were not significantly different in the both groups. The morphologic findings and functional parameters of the liver and kidney observed in common finch and white java sparrow fed with 3.0% QP diet showed evidence of slightly liver damage accompanied with increased release of enzyme and fatty change of the hepatocytes in common finch, suggested that the tissues in some animals can be damaged by feeding a diet supplemented with 3.0% QP.

• Applied Chemistry for Engineering
• /
• v.10 no.8
• /
• pp.1200-1209
• /
• 1999

Prediction model was composed by optimal parameter estimation from best fitting on reactant temperature profile, inlet and outlet temperature of coolant and yield of dual fixed-bed catalytic reactor(FBCR) which was measured in the industrial field. In order to design the FBCR which could obtain maximum conversion and yield, we investigated the effect of catalyst bed length and reactor radius changes. An uniform activity FBCR showed the best performance at z = 2.8 m of total catalysst bed length in case of reactor radius r = 0.01241 m and z =2.80 m(upper layer: 1.88 m, lower layer: 0.92 m) under reactor radius r = 0.01254 m for a dual activities FCBR. In case of reactor radius changes, the axial temperature profile and maximum radial temperature was rapidly risen for radius increase. The reactor radius decrease showed the opposite result.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.26 no.12
• /
• pp.1072-1082
• /
• 2015

In this paper, we propose two noise parameter measurement methods using spectrum analyzer. First method, we measure a noise correlation matrix using the 6-port network, and we calculate noise parameters using measured a noise correlation matrix. Second method, we directly measure noise figures of the DUT for source impedance changes, and then noise parameters are extracted from the measured noise figures. In order to measure a noise figure, we present a method of measuring a noise figure of the DUT that have arbitrary source impedances using spectrum analyzer and a method of eliminating a noise effect of a impedance tuner. Finally, the noise parameters of a passive and active DUT using proposed two methods are compared. The comparison shows that the two results obtained from for the two methods give almost identical noise parameters. The noise parameters measured by 6-port network accurately predict measured noise figures of the DUT for source impedance changes, and noise parameters measured by 6-port network is verified from the comparison.

• The Journal of the Acoustical Society of Korea
• /
• v.23 no.7
• /
• pp.503-513
• /
• 2004

In this paper, the thermal sensitivity, i .e. the temperature rise per unit acoustic power, was newly defined and proposed as a performance parameter of a tissue mimicking material. Eatable tofu (bean curd) manufactured by a factory was selected as a sample material for the experiment. The temperature changes were measured not only with the variation of ultrasonic irradiation time, acoustic power, depth from the sample surface. and the distance from the source transducer while adjusting the frequency to 8 MHz but also with the variation of frequency while acoustic power. depth from the sample surface. and the distance from the source transducer keeping constant. As a result of a consideration for the transformation of the measured temperature changes to thermal sensitivities. the thermal sensitivity was found to be sufficient to use as a Performance parameter for tissue mimicking material. The tofu as a tissue mimicking material showed the maximum thermal sensitivity at 10 MHz, as is a significant result to imply the possibility that the thermal sensitivity of real human tissue strong1y depends on the frequency.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.15 no.5
• /
• pp.605-614
• /
• 2005

In this paper, we present the design and implementation of an agent knowledge and QoS tuning methodology to improve the flexibility of agent-based flexible video-conference system. In order to improve the flexibility during video-conferencing, we propose a new T-INTER(Tuning-INTER) architecture of knowledge part in video-conference manager (VCM) agent in which an automatic QoS parameter tuning method is imbedded. The flexible video-conference system structured based on the proposed architecture can cope with the changes in service quality required by users. The VCM agent cooperates with other agents by protocols and executes the automatic QoS parameter tuning task whenever needed. By the tuned parameters, the system is able to flexibly cope with the internal or external changes and the burden of users can be decreased. In the experimental section, it is shown that our proposed system outperforms the existing system.

• Journal of Climate Change Research
• /
• v.7 no.3
• /
• pp.351-356
• /
• 2016

The carbon capture and storage (CCS), which collects and stores carbon dioxide in a geological site, is a promising option to mitigate climate change. However, there is the possibility of carbon dioxide leakage from the soil in the steps of collecting, transporting, and storing. To ensure the feasibility of this technology, it is important to monitor the leakage of carbon dioxide and to assess the potential impacts. As plants are sensitive to the changes in carbon dioxide in the soil environment, we can utilize plant parameter to detect the carbon dioxide leakage. Currently, chlorophyll a content is a conventional index indicating the changes in plants, however, this method is labor intensive and it only utilizes a small portion of leaves. To overcome its limitations, a simple spectroscopic parameter, DGCI (dark green color index), was suggested as an easy and quick indicator. In this study, we compared the values of chlorophyll a contents with DGCI from the experiment investigating the impacts of high underground $CO_2$ on grape plants. Results suggest that DGCI had high correlation with chlorophyll a contents and it has high potential to be utilized as an easy indicator to monitor plants' responses to $CO_2$ treatment.

• Korean Journal of Optics and Photonics
• /
• v.33 no.6
• /
• pp.324-330
• /
• 2022

We measured the Dill and Mack model parameters that determine the exposure and development characteristics of photoresists, respectively. First, photoresist samples were prepared while altering the exposure dose, and changes in transmittance were measured. Analyzing these results, the Dill model parameters A, B, and C were determined. In particular, the exact solution of the Dill model equation was used to determine the C parameter. In addition, changes in thickness were measured as a function of development time for different exposure doses, and the Mack model parameters R_min, R_max, a, and n were determined using the results. We also determined parameter values for the reduced Mack model that uses only three parameters, R_min, R_max, and n. The root mean square error between the model predictions and the measured values for the photoresist thickness was found to increase slightly compared to the case using the original Mack model with four parameters.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.342-343
• /
• 2013

AlSb is a promising material for optical devices, particularly for high-frequency and nonlinear-optical applications. And AlSb offers significant potential for devices such as quantum-well lasers, laser diodes, and heterojunction bipolar transistors. In this work we study molecular beam epitaxy (MBE) growth of an unstrained AISb film on a GaAs substrate and identify the real-time monitoring capabilities of in situ spectroscopic ellipsometry (SE). The samples were fabricated on semi-insulating (0 0 1) GaAs substrates using MBE system. A rotating sample stage ensured uniform film growth. The substrate was first heated to $620^{\circ}C$ under As2 to remove surface oxides. A GaAs buffer layer approximately 200 nm- thick was then grown at $580^{\circ}C$. During the temperature changing process from $580^{\circ}C$ to $530^{\circ}C$, As2 flux is maintained with the shutter for Ga being closed and the reflection high-energy electron diffraction (RHEED) pattern remaining at ($2{\times}4$). Upon reaching the preset temperature of $530^{\circ}C$, As shutter was promptly closed with Sb shutter open, resulting in the change of RHEED pattern from ($2{\times}4$) to ($1{\times}3$). This was followed by the growth of AlSb while using a rotating-compensator SE with a charge-coupled-device (CCD) detector to obtain real-time SE spectra from 0.74 to 6.48 eV. Fig. 1 shows the real time measured SE spectra of AlSb on GaAs in growth process. In the Fig. 1 (a), a change of ellipsometric parameter ${\Delta}$ is observed. The ${\Delta}$ is the parameter which contains thickness information of the sample, and it changes in a periodic from 0 to 180o with growth. The significant change of ${\Delta}$ at~0.4 min means that the growth of AlSb on GaAs has been started. Fig. 1b shows the changes of dielectric function with time over the range 0.74~6.48 eV. These changes mean phase transition from pseudodielectric function of GaAs to AlSb at~0.44 min. Fig. 2 shows the observed RHEED patterns in the growth process. The observed RHEED pattern of GaAs is ($2{\times}4$), and the pattern changes into ($1{\times}3$) with starting the growth of AlSb. This means that the RHEED pattern is in agreement with the result of SE measurements. These data show the importance and sensitivity of SE for real-time monitoring for materials growth by MBE. We performed the real-time monitoring of AlSb growth by using SE measurements, and it is good agreement with the results of RHEED pattern. This fact proves the importance and the sensitivity of SE technique for the real-time monitoring of film growth by using ellipsometry. We believe that these results will be useful in a number of contexts including more accurate optical properties for high speed device engineering.