• Title/Summary/Keyword: region contrast

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Segmentation and Recognition of Traffic Signs using Shape Information and Edge Image in Real Image (실영상에서 형태 정보와 에지 영상을 이용한 교통 표지판 영역 추출과 인식)

  • Kwak, Hyun-Wook;Oh,Jun-Taek;Kim, Wook-Hyun
    • The KIPS Transactions:PartB
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    • v.11B no.2
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    • pp.149-158
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    • 2004
  • This study proposes a method for segmentation and recognition of traffic signs using shape information and edge image in real image. It first segments traffic sign candidate regions by connected component algorithm from binary images, obtained by utilizing the RGB color ratio of each pixel in the image, and then extracts actual traffic signs based on their symmetries on X- and Y-axes. Histogram equalization is performed for unsegmented candidate regions caused by low contrast in the image. In the recognition stage, it utilizes shape information including projection profiles on X- and Y-axes, moment, and the number of crossings and distance which concentric circular patterns and 8-directional rays from region center intersects with edges of traffic signs. It finally performs recognition by measuring similarity with the templates in the database. It will be shown from several experimental results that the system is robust to environmental factors, such as light and weather condition.

Coherent Structures beneath Wind-Generated Deepwater Waves (심해 풍파 아래에서의 응집 구조)

  • Oh, Sang-Ho;Suh, Kyung-Duck;Mizutani, Natsuki
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.1
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    • pp.16-28
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    • 2007
  • The results of experimental investigation of coherent structures beneath wind-generated waves in deep water are presented. Vorticity fields of deepwater wind waves were visualized by analyzing the velocity fields obtained by PIV measurements under different wind and fetch conditions. In addition, spatio-temporal evolution of the coherent structures and subsequent changes in vertical profiles of the instantaneous vorticity were qualitatively examined. It was found that a coherent structure is formed right underneath the wave crest and traveled in phase with the surface wave. The direction of rotation of the coherent structure was contrary to the wave orbital motion when wind speed is less than 10 m/s, while was same as the wave orbital motion when wind speed is approximately 13 m/s and wave breaking occurs at the wave crest. In the near-surface region, complex vortex-vortex interactions were observed according to the traveling of the coherent structure. In contrast, coherent structures far below the water surface changed little due to weak influence of orbital motion by the surface waves.

Debaryomyces hansenii Strains from Valle De Los Pedroches Iberian Dry Meat Products: Isolation, Identification, Characterization, and Selection for Starter Cultures

  • Ramos, Jose;Melero, Yessica;Ramos-Moreno, Laura;Michan, Carmen;Cabezas, Lourdes
    • Journal of Microbiology and Biotechnology
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    • v.27 no.9
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    • pp.1576-1585
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    • 2017
  • Yeasts, filamentous fungi, and bacteria colonize the surface of fermented sausages during the ripening process. The source of this microbiota is their surrounding environment, and is influenced by the maturing conditions and starter cultures. Debaryomyces hansenii was previously isolated from several dry-cured meat products and associated with the lipolytic and proteolytic changes that occur in these products, influencing their taste and flavor. Therefore, this study isolated the yeast microbiota present in the casing from different meat products ("lomo," "chorizo," and "$salchich{\acute{o}}n$") from the Valle de los Pedroches region in southern Spain. D. hansenii was by far the most abundant species in each product, as all 22 selected isolates were identified as D. hansenii by biochemical and/or molecular methods. In contrast, no yeasts were found in the meat batter. These data constitute the first study of the yeasts present in "lomo" sausages and particularly the highly appreciated Valle de los Pedroches "lomo" sausages. Furthermore, the resistance of these isolates to different pHs, temperatures, and saline stress was studied, together with their catabolic characteristics. Based on the results, certain isolates are proposed as valuable candidate starter cultures that could improve both the manufacture and the flavor of such dry-cured meat products, and provide an understanding of new mechanisms involved in stress tolerance. Applied medium-scale industrial tests are currently in progress.

A Numerical Analysis on Transient Fuel Temperatures in a Military Aircraft with Additional Fuel Supplies and Return (추가연료 공급,회송량에 따른 항공기내 연료온도 변화에 대한 수치해석적 연구)

  • Kim,Yeong-Jun;Kim,Chang-Nyeong;Kim,Cheol-In
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.1
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    • pp.73-84
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    • 2003
  • A transient analysis on fuel temperatures in an aircraft was studied using the finite difference method. Numerical calculation was performed by an explicit method of modified Dufort-Frankel scheme. Among various missions, close air support mission was considered with 20% hot day ambient condition in subsonic region. The aircraft was assumed to be in turbulent flow. The fuel system model with additional fuel supplies and return concept was considered. As a result of this analysis, the fuel tank temperatures have increased with the increase of the additional fuel supplies. In contrast to tank temperatures, the fuel temperature at the engine inlet has decreased with the increase of additional fuel supplies except in some in-flight phases having high engine fuel flow. From this analysis, the fuel system with the additional fuel supplies and return concept has been shown to be an effective method to decrease the engine inlet fuel temperature. Also, it has been shown that fuel flow rate through fuel/oil heat exchanger is a key factor influencing fuel temperature.

Extreme Enhancements in GPS TEC on 8 and 10 November 2004

  • Chung, Jong-Kyun;Jee, Gun-Hwa;Kim, Eo-Jin;Kim, Yong-Ha;Cho, Jung-Ho
    • Bulletin of the Korean Space Science Society
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    • 2010.04a
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    • pp.30.2-30.2
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    • 2010
  • It is a mistaken impression that the midlatitude ionosphere was a very stable region with well-known morphology and physical mechanism. However, the large disturbances of midlatitude ionospheric contents in response to global thermospheric changes during geomagnetic storms are reported in recent studies using global GPS TEC map and space-born thermospheric UV images, and its importance get higher with the increasing application areas of space navigation systems and radio communication which are mostly used in the midlatitudes. Positive and negative storm phases are used to describe increase and decrease of ionospheric electron density. Negative storms result generally from the enhanced loss rate of electron density according to the neutral composition changes which are initiated by Joule heating in high-latitudes during geomagnetic storms. In contrast, positive ionospheric storms have not been well understood because of rare measurements to explain the mechanisms. The large enhancements of ground-based GPS TEC in Korea were observed on 8 and 10 November 2004. The positive ionospheric storm was continued except for dawn on 8 November, and its maximum value is ~65 TECU of ~3 times compared with the monthly mean TEC values. The other positive phase on 10 November begin to occur in day sector and lasted for more than 6 hours. The O/N2 ratios from GUVI/TIMED satellite show ~1.2 in northern hemisphere and ~0.3 in southern hemisphere of the northeast Asian sector on 8 and 10 November. We suggest the asymmetric features of O/N2 ratios in the Northeast Asian sector may play an important role in the measured GPS TEC enhancements in Korea because global thermospheric wind circulation can globally change the chemical composition during geomagnetic storms.

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Cervical Ganglioneuroma Associated with Neurofibromatosis Type 1 (제 1형 신경섬유종증에 동반된 경부 신경절신경종)

  • Choi, Eui-Chul;Kim, Jun-Hyuk;Shin, Ho-Seong;Lee, Ji-Hye;Lee, Young-Man
    • Archives of Plastic Surgery
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    • v.37 no.4
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    • pp.477-480
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    • 2010
  • Purpose: Ganglioneuromas are well-differentiated tumors derived from neuroectodermal neural crest cells. Although these tumors can occur anywhere along the sympathetic chain from the base of the skull to the pelvic cavity, they usually develop in the posterior mediastinum and retroperitoneum these tumors are rarely found in the cervical region. Method: We report the case of a 16-year-old male patient with neurofibromatosis type 1 who was admitted because of a palpable mass centrally located on the left side of the neck. A preoperative contrast-enhanced neck computed tomography image showed a low-density homogeneous mass on the parapharyngeal space along with marked displacement of the trachea and carotid vessels. Round and soft masses were also detected on both axillae. Results: The patient subsequently underwent complete excision of the neck mass via the transcervical approach. The mass was smooth and well encapsulated between the sternocleidomastoid muscle and the trachea. Further, the mass appeared to arise from the cervical sympathetic chain, which was preserved during surgery. Both the axillary masses were also excised. The histopathological findings were ganglioneuroma for the neck mass and neurofibroma for both the axillary masses. Conclusion: Cervical ganglioneuromas are rare tumors that present as enlarging parapharyngeal cervical masses in the oropharynx or neck. To our knowledge, a case of cervical ganglioneuroma associated with neurofibromatosis type 1 has never been reported. In patients with neurofibromatosis, multiple tumors may develop, and therefore periodic clinical and radiological follow-up is recommended. Further, repeated imaging analysis should be performed if the presence of another tumor is suspected.

Right-to-left Shunting Ventricular Septal Defect in a Dog (개에서 발생한 우-좌 단락 심실 중격 결손 증례)

  • Yun, Sookyung;Kim, Boeun;Youn, Hwayoung;Choi, Mincheol;Yoon, Junghee
    • Journal of Veterinary Clinics
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    • v.32 no.4
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    • pp.343-346
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    • 2015
  • A 4-year-old castrated male Dachshund was presented with a chronic history of dyspnea and cyanosis. Complete blood count revealed marked polycythemia with a hematocrit of 79.7%. Thoracic radiographs showed mild right-sided cardiac enlargement. Echocardiography showed a large ventricular septal defect in the left ventricular outflow tract region just proximal to the aortic valve. On Doppler echocardiography, right-to-left shunt flow through the defect was found and confirmed by contrast echocardiography. Based on these diagnostic findings and clinical signs, the dog was diagnosed as right-to-left shunting ventricular septal defect. Phlebotomy and oxygen supplement were performed, but the dog died the day after presentation.

Comparison Between Two Detection Methods for HPV16, HPV18 and P16Ink4a Biomarkers in Diagnosis of Abnormal Cervical Cytology

  • Khazaei, Sedigheh;Izadi, Babak;Mirbahari, Seyed Ghasem;Madani, Seyed Hamid;Khosravi, Shohre Malek;Alagha, Mohsen Emami;Sajadimajd, Soraya
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.12
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    • pp.5223-5227
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    • 2016
  • Background: Cervical cancer is the second most common cancer among women in many populations. While the Pap smear is a well established screening test it suffers from both false-positive and false-negative results in diagnosis of cancers and precancerous states. In this study, immunocytochemistry of the P16 biomarker and HPV-PCR were compared for their diagnostic potential. Materials and methods: In the study, we obtained pairs of specimens from 45 women with cervical dysplasia. One sample was placed in a liquid-based solution, and processed for staining of sections with antibodies to P16. HPV-PCR was performed on the other and the results obtained were analyzed by T-test using SPSS v. 15. Results: Using HPV-PCR 71% of the samples were found to be infected with either HPV 16 or HPV 18, and the rate of infection did not have a statistically significant relationship with higher grades of dysplasia (p= 0.253). In contrast, with immunocytochemistry evaluation of P16, 64% of the specimens were positive, but the percentage of positive results significantly increased with higher grades of dysplasia (p= 0.0001). Conclusion: Employment of the P16 marker as an optional test might be preferable over HPV-PCR for cervical dysplasia in our geographical region.

Visualization of Epidermis and Dermal Cells in ex vivo Human Skin Using the Confocal and Two-photon Microscopy

  • Choi, Sang-Hoon;Kim, Wi-Han;Lee, Yong-Joong;Lee, Ho;Lee, Weon-Ju;Yang, Jung-Dug;Shim, Jong-Won;Kim, Jin-Woong
    • Journal of the Optical Society of Korea
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    • v.15 no.1
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    • pp.61-67
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    • 2011
  • The confocal laser scanning microscopy and two-photon microscopy was implemented based on a single laser source and an objective lens. We imaged and compared the morphology of identical sites of ex vivo human skin using both microscopes. The back-scattering emission from the sample provided the contrast for the confocal microscopy. The intrinsic autofluorescence and the second harmonic generation were used as the luminescence source for the two-photon microscopy. The wavelength of the Ti:Sapphire laser was tuned at 710 nm, which corresponds to the excitation peak of NADH and FAD in skin tissue. The various cell layers in the epidermis and the papillary dermis were clearly distinguished by both imaging modalities. The two-photon microscopy more clearly visualized the intercellular region and the nucleus of the cell compared to the confocal microscopy. The fibrous structures in the dermis were more clearly resolved by the confocal microscopy. Numerous cells in papillary dermal layer, as deep as $100\;{\mu}m$, were observed in both CLSM and two-photon microscopy. While most previous studies focused on fibrous structure imaging (collagen and elastin fiber) in the dermis, we demonstrated that the combined imaging with the CLSM and two-photon microscopy can be applied for the non-invasive study of the population, distribution and metabolism of papillary dermal cells in skin.

Predicting lipoabdominoplasty complications with infrared thermography: a delta-R analysis

  • Resende, Patricia Rodrigues;Brioschi, Marcos Leal;Meneck, Franciele De;Neves, Eduardo Borba;Teixeira, Manoel Jacobsen
    • Archives of Plastic Surgery
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    • v.48 no.5
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    • pp.553-558
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    • 2021
  • The diagnosis of the main complications resulting from lipoabdominoplasty has not yet been standardized. Infrared thermal imaging has been used to assess possible complications, such as necrosis and changes in micro- and macro-circulation, based on perforator mapping techniques, among others. The objective of this study was to present two clinical cases involving thermal imaging monitoring of the healing process of lipoabdominoplasty in the immediate postoperative evaluation and its preliminary results. Infrared thermography was performed 24 hours after the operation and on postoperative days 5, 25, and 27. In clinical case 1, it was found that the delta-R (∆TR)-defined as the difference in minimum temperature between the highest and lowest points in the SA3 region (caution suction area) following the classification established by Matarasso-was 0.4℃ at 24 hours after surgery and decreased to 0.1℃ on a postoperative day 5. There were no complications in this case. In contrast, in clinical case 2, the ∆TR was 1.7℃ at 24 hours after surgery (upon hospital discharge) and remained high, at 2.2℃, on postoperative day 5. A higher ∆TR was found in the second patient, who developed necrosis of the surgical wound. The ∆TR thermal index may be a new tool for predicting possible complications, complementing the clinical evaluation and therapeutic decision-making.