• Title/Summary/Keyword: echo pattern

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Settlement Characteristics of Three Type of Artificial Reefs on Sandy Bottom in the Eastern Coast of Korea (동해안 사질지반에 시설된 인공어초 3종의 매몰 특성)

  • Kim, Dae-Kweon;Kim, Wan-Ki;Son, Yong-Soo;Yoon, Jang-Tack;Gong, Yong-Gun;Kim, Young-Dae;Lee, Ji-Hyun
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.2
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    • pp.359-364
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    • 2008
  • Using multi beam echo sounder, side scan sonar and scuba diving equipment, ceramic type, uneven type and semicircle-ramus type reefs into sandy bottom were ascertained, the depth of submersion in 7.2-10.3m on the coast of Gangneung, East of Korea, forty uneven type artificial reefs(AR) were totally buried into the sandy bottom. Two of five semicircle-ramus type ARs had only of their top area exposed. For most of the 45 ceramic reefs, only the upper 25-150cm of ARs were visible. The burial pattern is different in west and east side of the reefs, where the east side is deeply buried compared to the west side. From these results. it is recommended that sufficient analysis of bottom structure and materials especially in the sandy sea area should be undertaken in order to determine the best type of artificial reefs to be deployed and the best location for depoloyment.

Design of CPW-Feed Multi-Band Monopole Antenna for Next Generation WLAN Systems (차세대 WLAN을 위한 CPW 급전 다중대역 모노폴 안테나 설계)

  • Choi, Yong-Seok;Seong, Hyeon-Kyeong;Rho, Jung-Kyu
    • Journal of Satellite, Information and Communications
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    • v.9 no.1
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    • pp.38-44
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    • 2014
  • In this paper, we designed a multiband monopole antenna for next-generation WLAN system. In conventional WLAN system, UWB antennas were used together, and, because the radiation occurs in different parts depending on the antenna structure, it has the disadvantage of having an unstable impulse response characteristic due to dispersion characteristics. Although a UWB antenna that has suitable radiation pattern for WLAN band, it does not have good impedance matching and has severe echo. Therefore, in this paper, a monopole antenna was designed by using CPW power feed so that various impedances can be easily implemented when designing an antenna and more parameters can be derived that can be used for design for optimal performance.

Spatial characteristics of fish distribution lured by artificial reefs in Jeju marine ranching area (제주 바다목장 해역의 인공어초에 유집된 어군 분포의 공간적 특성)

  • Hwang, Bo-Kyu;Jang, Ho-Young
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.50 no.1
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    • pp.30-38
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    • 2014
  • Hydro-acoustic survey was carried out to investigate the spatial characteristics of fish distribution near two artificial reefs (AO: large octagonal semi-sphere and AC: combined custom built) having different types in Jeju marine ranching area. The survey system consisted of scientific echo sounder (EK60), DGPS system, and ECDIS (Mecys). Field survey was conducted on August and October 2012 with star survey and line transect survey line method, and species composition was investigated from gill net fishing survey. The acoustic signals from individual fishes and small fish schools were mainly recorded around AO, but large and strong signals from large fish school were mainly detected in the top layer of and the water column near AC. The echogram suggest that the fish aggregation for the two types of AO and AC exist the significant difference in fish species and spatial distribution pattern.

A Case of B Cell Lymphoma Presenting with Multiple Osteolysis in a Juvenile Golden Retriever (다발성 골 융해를 동반한 림프종 증례)

  • Choi, Ji-Hye;Lee, Jin-Soo;Kim, Hyun-Wook;Choi, Ul-Soo
    • Journal of Veterinary Clinics
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    • v.29 no.1
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    • pp.98-102
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    • 2012
  • A 1.5-year-old male Golden Retriever was presented with worsening lameness of two month duration. Abnomral findings of blood works and serum chemistry included anemia, thrombocytopenia, hypercalcemia and hyperglobulinemia. Radiography revealed osteolysis of polyostotic regions including right femur and tibia, bilateral ilium, and spinous processes from the 13th thoracic vertebra to 5th lumbar vertebra. Enlarged multiple lymph nodes and mixed echo pattern of muscular region ventral to vertebra were observed with ultrasonography. Because concentrations of both parathyroid hormone and parathyroid hormone related peptide were all within reference ranges, humoral hypercalcemia by tumor was ruled out and extensive osteolysis was considered as the cause of hypercalcemia. Based on radiographic and ultrasonographic study, lymphoma, multiple myeloma and osteomyelitis were included in differential diagnosis. Fungal serologic test was negative. Monoclonal gammopathy was not found on serum protein electrophoresis. Cytological and histopathological examinations of the lytic lesions revealed neoplastic lymphoid proliferation, and B cell type clonal expansion was detected by polymerase chain reaction for the antigen receptor gene rearrangement. The case was diagnosed as B cell lymphoma involving polyostotic regions.

Depositional Environment and Distribution of Heavy Metal off the Shihwa Dam

  • Oh, Jae-Kyung
    • Journal of the korean society of oceanography
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    • v.32 no.3
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    • pp.120-127
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    • 1997
  • Depositional environment off the Shihwa Dam has been studied to investigate the change of sedimentation process and the pollution. In order to understand how the sediments are distributed, polluted and modified, depositional factors have been analyzed and compared with the previous data. Study area, located off the Shihwa Dam, was surveyed to collect 25 bottom samples and 2 cores in 1996 and echo-sounding in 1997. These sediments were analyzed for the study of the global characteristics of sediment such as grain size and organic matter. Among these samples, the selected twenty surface sediments were analyzed for the comparison with their contents of metallic elements (Al, Mn, Fe, V, Cr, Co, Ni, Cu, Zn, Cd, Pb, As). According to field and lab analysis of sediments, three sedimentological zones have been generally identified around study area; near the dam (sandy Silt), near the dike (Sand) and offshore (silty Sand) zones. Textural parameters show that the content of silt and clay is dominant near the dam excepting the dike zone of LNG Storage Base and offshore (Palmido). The total concentration of Mn, Ni, Fe, Zn and Cd in bulk sediments was increased after the construction of the dam, while the content of Mn and Cr were higher near tidal channel than in the offshore area. Meanwhile, the annual increasing pattern of some heavy metal has appeared in this area. Based on this primary study, modification of the depositional environment may be caused by the construction of the dam and LNG Storage Base. Additionally, environmental evaluation on organic/inorganic factors has been suggested for interpreting environmental changes caused by coastal development in the nearshore such as the Shihwa coastal area.

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Diagnostic Imaging of Massive Hepatocellular Carcinoma in 5 Dogs (개의 종괴형 간세포암종에 대한 진단 영상 소견에 대한 고찰)

  • Choi, Ji-Hye;Kim, Ah-Rim;Keh, Seo-Yeon;Choi, Hee-Yeon;Jang, Jae-Young;Yoon, Jung-Hee
    • Journal of Veterinary Clinics
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    • v.27 no.4
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    • pp.474-482
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    • 2010
  • Hepatocellular carcinoma (HCC) is a primary hepatic neoplasms in dogs. Three types of HCC such as massive, nodular and diffuse form were reported. Massive HCC is most common and has relatively better prognosis than other forms because this type of HCC can be removed surgically and has low frequency of relapse or metastasis. Diagnostic image can provide useful information for shape and internal structure of the hepatic mass as well as the location and adhesion or invasiveness of the mass to establish surgical plan to remove the mass safely. In this study, we investigated diagnostic features of massive HCC in 5 dogs. Radiography showed soft tissue mass in cranial abdomen in 3 dogs. On ultrasonography, all dogs had a solitary hepatic mass with mixed echo pattern with anechoic cysts, which represented necrosis and hemorrhage. The radiographic and ultrasonographic findings of affected hepatic lobe were compared with the macroscopic findings through laparotomy. Computed tomography was performed to check metastasis and figure out the origin of the mass in two dogs. Ultrasonography is useful and relatively sensitive examination for diagnosis and planning for surgery in canine massive HCC.

Classification of Sedimentary Facies Using IKONOS Image in Hwangdo Tidal Flat, Cheonsu Bay (IKONOS 영상을 이용한 천수만 황도 갯벌 표층 퇴적상 분류)

  • Ryu, Joo-Hyung;Woo, Han Jun;Park, Chan-Hong;Yoo, Hong-Rhyong
    • Journal of Wetlands Research
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    • v.7 no.2
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    • pp.121-132
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    • 2005
  • To classify the surface sedimentary facies using IKONOS image collected over Hwangdo tidal flat in Cheonsu Bay, the optical reflectance was compared for characterizing various sedimentary environments such as grain size, tidal channel pattern and area ratio of surface remnant water. The intertidal DEM (Digital Elevation Model) was generated by echo-sounder for analyzing the relationship between IKONOS image and sedimentary environments including topography. The boundary of the optical reflectance between mud-mixed facies and sand facies was distinct, and discrimination of the associated sandbar feature was also possible. The mud-mixed facies coupled with intricate tidal channels is confined to the relatively hi호 topography of Hwangdo tidal flat. The boundary between mud and mixed flat was indistinct in IKONOS optical reflectance but it would have a difference in the area ratio of surface remnant water. The dark area in the image represented the well developed sand facies having a lot of surface remnant water due to the relatively low surface topography. The overall accuracy of characterizing the surface sediment facies by maximum likelihood classification method was 86.2 %. These results demonstrate that high spatial resolution satellite imagery such as IKONOS coupled with knowledge of grain size, surface remnant water and tidal channel network can be effectively used to characterize the surface sedimentary facies (mud, mixed and sand) network of the tidal flat environments.

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Towards Routine Clinical Use of Radial Stack-of-Stars 3D Gradient-Echo Sequences for Reducing Motion Sensitivity

  • Block, Kai Tobias;Chandarana, Hersh;Milla, Sarah;Bruno, Mary;Mulholland, Tom;Fatterpekar, Girish;Hagiwara, Mari;Grimm, Robert;Geppert, Christian;Kiefer, Berthold;Sodickson, Daniel K.
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.2
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    • pp.87-106
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    • 2014
  • Purpose : To describe how a robust implementation of a radial 3D gradient-echo sequence with stack-of-stars sampling can be achieved, to review the imaging properties of radial acquisitions, and to share the experience from more than 5000 clinical patient scans. Materials and Methods: A radial stack-of-stars sequence was implemented and installed on 9 clinical MR systems operating at 1.5 and 3 Tesla. Protocols were designed for various applications in which motion artifacts frequently pose a problem with conventional Cartesian techniques. Radial scans were added to routine examinations without selection of specific patient cohorts. Results: Radial acquisitions show significantly lower sensitivity to motion and allow examinations during free breathing. Elimination of breath-holding reduces failure rates for non-compliant patients and enables imaging at higher resolution. Residual artifacts appear as streaks, which are easy to identify and rarely obscure diagnostic information. The improved robustness comes at the expense of longer scan durations, the requirement for fat suppression, and the nonexistence of a time-to-center value. Care needs to be taken during the configuration of receive coils. Conclusion: Routine clinical use of radial stack-of-stars sequences is feasible with current MR systems and may serve as substitute for conventional fat-suppressed T1-weighted protocols in applications where motion is likely to degrade the image quality.

Ultrasonographic Features of Intra-abdominal Abscess (복부내 농양의 초음파 소견)

  • Cho, Kil-Ho;Jung, Kyung-Hee;Hwang, Mi-Soo;Chang, Jae-Chun;Kwun, Koing-Bo;Min, Hyun-Sik
    • Journal of Yeungnam Medical Science
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    • v.2 no.1
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    • pp.87-93
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    • 1985
  • Intraabdommal abscess usually causes distress with fever, leukocytosis, pain and toxicity. Diagnosis of intraabdominal abscess is occasionally difficult and It has high morbidity. However radiologic method, such as ultrasonography, CT scan, or RI scan are helpful to early detection of intraabdominal abscess. Among these methods, ultrasonography is a non-invasive technique and performed without discomfort to patient. And also differential diagnosis between cystic and solid lesion is very easy and sequential ultrasonography in same patient is valuable for the evaluation of treatment effect. We analyzed the ultrasonic features of 48 cases with intra-abdominal abscesses and the results are as follows; 1. In total 48 cases, the intra-abdominal abscesses were 30 cases, the retroperitoneal abscesses, 5 cases, and the visceral abscesses, 13 cases. 2. The causes of the intra-abdominal abscesses were perforating appendicitis (25 cases), postoperative complications (5 cases), pyogenic and amebic hepatic abscesses (13 cases), and the others (5 cases). 3. Round or oval shaped lesions were 26 cases (54%), irregular shape, 18 cases (38%), and multiple abscess formation in 4 cases (8 %). 4. The size of the lesions were between 5 and 10cm in diameter in 54% of total 48 cases, and the most frequent feature of the echo-pattern of the lesions was cystic with or without internal echogenicity (69%).

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A Comparative Analysis of Basal Body Temperature to Ultrasound, as a Method of Ovulation Detection in Induced Ovulatory Menstrual Cycles (배란유도주기에 따른 초음파검사와 기초체온표의 비교분석)

  • Choi, W.;Suh, B.H.;Lee, J.H.
    • Clinical and Experimental Reproductive Medicine
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    • v.12 no.2
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    • pp.25-37
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    • 1985
  • Four points on the basal body temperature (B.B.T.) curve was correlated with the estimated time of ovulation, as determined by serial ultrasound in 50 induced menstrual cycles from 22 subjects. The time of ovulation was estimated by measuring the maximal diameter of follicles and observing the morphologic changes within the ovary from follicle to corpus luteum. The results were as following; 1. The diameter of the follicle measured at the day before disappearance was 21.1 mm on an average (S.D.: 2.14). The average follicular growth for 4 days before ovulation was measured at a rate of 2.8 mm/day, and rapid growth of follicle was observed 3.1 mm/day at the day before. 2. The changes associated with rupture of the follicles were the followings, in order of frequency; decrease in size(94%), disappearance of follicles(64%), fluid in the Cul-de-Sac(26%) and increased internal echoes(16%). 3. Only 20 of 50 cycles, exhibited a BBT dip and correlated with the estimated time of ovulation by ultrasound in 2 of which cases(10%). BBT nadir, 30 of 50 cycles, correlated in 5(16.7%). The first day of hyperthermic plateau(FDHP) and BBT coverline was exhibited in all cycles, correlated in 41(82%) and 35(70%) cases. 4. The relationship between the diameter of dominant dominant follicle, measured by ultrasound, and the basal body temperature curve were as following. During cycles in which dip was observed on the BBT curve, the follicular diameter were 10.5${\pm}$2.12 mm on 4 days prior to the point (D-4), and 12.5${\pm}$2.12 mm (D-3), 15.5${\pm$2.12 mm (D-2), 17.0${\pm}$1.41 mm (D-1) and 21.5${\pm}$2.12 mm just prior to the dip (D-0). In the nadir; 9.6${\pm}$1.67 mm (N-4), 12.8${\pm}$1.79 mm (N-3), 16.2${\pm}$1.92 mm (N-2), 18.2${\pm}$2.17 mm (N-1) and 21.4${\pm}$2.61 mm (N-0). In the First day of Hyperthemic Plateau (FDHP); 9.8${\pm}$1.36 mm (F-4), 12.4${\pm}$1.41 mm (F-3),15.1${\pm}$1.57 mm (F-2), 18.1${\pm}$1.67 mm (F-1) and 21.2${\pm}$2.25 mm (F-0). In the BBT coverline endopint; 9.9${\pm}$.39 mm (C-4), 12.5 ${\pm}$1.44 mm (C-3), 15.2${\pm}$1.64 mm (C-2), 18.0 ${\pm}$1.69 mm (C-1), and 21.2${\pm}$2.31 mm (C-0). 5. The relationship between the ultrasonographic signs of ovulation and the basal body temperature curve were as following. The BBT dip correlated with the ovulation in 2 cases, which revealed decrease in follicular diameter (100%), fluid pattem in the Cul-de-Sac (1 case, 50%) and complete disappearance of follicle (1 case, 50%). In the nadir (5 cases); the ultrasonographic signs of ovulation were decrease in follicular diameter (5 cases, 100%), fluid pattern in the Cul-de-Sac (1 case, 20%) and complete disappearance of follicle (3 cases, 60%). In the First day of Hyperthermic Plateau (41 cases); decrease in follicular diameter (40 cases, 97.6%), fluid pattern in the Cul-de-Sac (11 cases, 26.8%), appearance of internal echo and thickening of the wall (6 cases, 14.6%) and com plete disappearance of follicle (28 cases, 68.3%). In the BBT coverline endpoint (35 cases); decrease in follicular diameter (33 cases, 94.3%), fluid pattern in the Cul-de Sac (9 cases, 25.7%), appearance of internal echo and thickening of the wall (5 cases 14.3%) and complete disappearance of follicle (20 cases, 57.1%).

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