• Ocean and Polar Research
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• v.25 no.3
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• pp.257-267
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• 2003

Deep-sea bottom photographs acquired in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific were analyzed to reveal the controlling processes for the spatial variation of manganese nodule. The results show that regional-scale occurrence variations of manganese nodule are mainly controlled by primary productivity of surface water, sedimentation rate, and water depth (or carbonate compensation depth). As a result, the diagenetic accretion on nodules increases toward southwest while hydrogenetic accretion increases toward northeast. Considering the northwestward movement of Pacific Plate, this regional-scale variation of manganese nodule occurrence seems to be affected by oceanic environment during the active growth period (Oligocene-Miocene) of Pacific Plate.

• Ocean and Polar Research
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• v.36 no.4
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• pp.373-381
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• 2014

Korea contract Mn-nodule field in the NE equatorial Pacific is composed of seven sectors with average water depths of 4,513-5,025 m. Of the various factors controlling the properties of Mn-nodule, it seems that water depth is likely connected to the chemical composition and occurrence of nodules. To test whether such an assumption held in each sector, we reviewed previous research data accumulated since 1994 for one of the northern sectors (hereafter KR1) where there are stark contrasts in water depth. High-resolution seabed mapping clearly separates a northern part (KR1N) from a deeper southern part (KR1S), cutting across in the middle of the KR1. In addition, significant volcanic activities forming numerous seamounts are distinctive especially in KR1N. In terms of nodule occurrence, manganese nodules in KR1S are comparatively larger (2-4 cm) with a discoidal shape, while those in KR1N are generally small (<2 cm) with poly-lobate and irregular shapes. Nodules in KR1N also have lower Co, Cu, Mn and Ni, and higher Fe contents. The spatial separation in nodule characteristics might be caused by volcanic activities in KR1N rather than water depth contrast. During the formation of the seamounts in KR1N, rock fragments and volcanic ashes as new nuclei of the nodules would have been continuously generated. As a result, the nodules could not grow larger than 2 cm and display the shapes of a newbie (i.e., irregular and poly-lobate shapes). Moreover, significant Fe supply from volcanic activities probably decreases the Mn/Fe ratio, which may lead to the KR1 nodules being misinterpreted as a hydrogenic in origin compared to other sectors where a high Mn/Fe ratio is present.

• Economic and Environmental Geology
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• v.45 no.5
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• pp.477-486
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• 2012

High-resolution bathymetry and physico-chemical properties of manganese nodules were explored to identify the relationship between morphological features and nodule occurrences in the KR1, one of the Korean contract nodule fields located in the NE Pacific. The high-resolution seabed mapping showed that the southwestern sector of the KR1 (KR1-1) was relatively deeper than the northeastern sector (KR1-2) which is occupied by small-scale seamounts. In terms of nodule occurrence, manganese nodules in the KR1-1 were comparatively larger (2-4 cm) with rough surface (t-type) and discoidal shapes (D-type), while those in the KR1-2 were generally small (<2 cm) with smooth surface (s-type) and irregular shapes (I-type). In addition, the nodules in the KR1-1 had higher contents of Cu, Mn and Ni. Such connections of water depths to nodule appearances and metal contents are commonly observed in the Pacific nodule fields. On the other hand, the nodules in the KR1-2 tend to be controled by morphological features. The seamounts in the KR1-2 might continuously provide rock fragments as new nuclei of manganese nodules. As a result, the nodules could not grow over than 2 cm and showed the shapes of a newbie (i.e., smooth surface and irregular shapes). As a result, our observations indicate that occurrence features of manganese nodules could be subjected to water depths and seabed morphology simultaneously.

• Journal of Chest Surgery
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• v.15 no.2
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• pp.148-154
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• 1982

The experience with operative treatment for peripheral situated solitary circumscribed lesions of the lung at the Department of Thorac. & Cardiovasc. Surg., Korea University Hospital during 8 years from March 1974, through April, 1982 was reviewed. Our criteria for Solitary pulmonary nodule were 1. Round or Ovoid shape 2. Surrounded by normal lung Parenchyme 3. Well circumscribed peripheral location 4. No other visible pulmonary diseases on chest X-ray except minimal atelectasis or pneumonitis 5. Largest diameter less than 8 cm Of the 55 patients reviewed, there were 69% of malignancy and 31% of benign pulmonary diseases. In malignancy 38 patients, there were 18 patients with squamous cell carcinoma, 8 patients with undifferentiated large cell carcinoma, 2 patients with undifferentiated small cell carcinoma, 10 patients with adenocarcinoma and patient with metastatic carcinoma. In benign pulmonary nodule 17 patients, here were 5 patients with tuberculoma, 5 patients with aspergilloma, 2 patients with A-V fistula, 1 patient with pulmonary blastoma, 1 patient with paragonimiasis, and 1 patient with lung abscess. Overall male to female occurrence ratio was 39:16, and most prevalent age incidence was 7th decades. Most frequent size distribution was 4-6 cm in diameter. All of benign diseases were cured by resection and 66% of malignancy performed operation and has 75% resectability.

• Journal of Ocean Engineering and Technology
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• v.23 no.6
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• pp.32-38
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• 2009

An FMEA for the waterjet-lifter of a DSNM is performed to prevent the occurrence of device failure. A waterjet-lifter raises and transports manganese nodules from the deep-sea floor up to a somewhat elevated place, from which a pin-scraper transports the lifted nodules to the inner space of the DSNM. A concept design for a device using the axiomatic design methodology is shown as the mapping between the functional domain and physical domain. The FMEA for a DSNM is introduced briefly and the rating criteria of severity, occurrence, and detection for the DSNM are defined. The FMEA of the functional requirements of a DSNM device is accomplished. Three kinds of failure modes, as well as their effects and causes, are predicted. Current design control methods for detecting potential failures, such as physical or computational experiments, design confirmation, and mathematical calculation, are described and the recommended actions for several significant causes are suggested.

• Economic and Environmental Geology
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• v.24 no.4
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• pp.335-346
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• 1991

It is observed that calcareous nodules of the Hwajeol Formation are locally skarnized in the Sangdong district, in which the skarn mineralization extends 5 Km westward from the Sangdong mine area to the Hwajeolchi area. After a hidden granite beneath the Sangdong mine was discovered by exploration drillings, the exploration teams of the Sangdong mine and the Korean Mining Promotion Corporation have assumed that the skarn nodule of the Hwajeol Formation was derived from emplacement of a granite in deep place and the occurrence of hidden ore bodies below the skarn, and they have discovered high grades of tungsten orebody in the same horizon of the Sangdong ore body. Mutual genetic relatioships between epidote and garnet may be explained by following chemical reactions $Ca_2FeA_{12}$ $Si_3O_{12}(OH)+CaCO_3=Ca_3(Fe,\;Al)_2$ $SiO_{12}+1/2CO_2+1/2H^+Ca_3FeSi_3O_{12}+SiO_2+CO_2=2CaFeSi_{12}O_6+CaCO_3+1/2O_3$. It is concluded that epidote and garnet are useful as target minerals indicating a potential occurrence of deep seated hidden ore body. Since the epidote may inform the emplacement of the granite, while the garnet in the skarn nodule of the Hwajeol Formation may reflect a strong hydrothermal mineralization taking place from the depth.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.4
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• pp.323-337
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• 1999

Seafloor morphology and manganese nodule occurrence were studied in the Korea Deep-sea Environmental Study (KODES) area, northeast equatorial Pacific, to understand their relationship. Study area is composed of three elongated valleys and hills with about 100~200 m height along NNE-SSW direction. Valley region is generally flat. However, hill region is very rugged with big cliffs of about 100m height and small depressions of several tens of meters depth. Tectonic movement along the Clarion-Clipperton fracture zone, consequent formation of elongated abyssal hills and Valleys, erosion of siliceous bottom sediments by bottom currents, and dissolution of carbonate sediments on the abyssal hills below CCD result in the rugged morphology. Manganese nodule occurrence is closely related to the morphology of the study area; mostly rounded-shaped manganese nodules with about 5 cm diameter are abundant on the flat valley region, whereas irregular shaped nodules (or manganese crust) with less than 5 cm to about 1 m diameter occur on the hill. These results supports the previous reports that nodule abundance, composition, and morphology are variable both on regional and local small scales on the seafloor even within some abundant nodule provinces depending on oceanographic characteristics such as bathymetric features, surface sediment type, sediment thickness, and so on. We suggest that such oceanographic characteristics affect interrelatedly on the formation of manganese nodules, and tectonic movement of the Pacific plate ultimately constrain the nodule occurrence. A potential mining place in the KODES area seems to be the valley region, which is elongated to the NNW-SSE direction with 3-4 km width.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.3
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• pp.1104-1120
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• 2020

The chest X-rays are a common way to diagnose lung cancer or pneumonia. In particular, the finding of a lung nodule is the most important problem in the early detection of lung cancer. Recently, a lot of automatic diagnosis algorithms have been studied to find the lung nodules missed by doctors. The algorithms are typically based on segmentation network like U-Net. However, the occurrence of false positives that similar to lung nodules present outside the lungs can severely degrade performance. In this study, we propose a multi-task learning method that simultaneously learns the lung region and nodule-labeled data based on the prior knowledge that lung nodules exist only in the lung. The proposed method significantly reduces false positives outside the lung and improves the recognition rate of lung nodules to 83.8 F1 score compared to 66.6 F1 score of single task learning with U-net model. The experimental results on the JSRT public dataset demonstrate the effectiveness of the proposed method compared with other baseline methods.

• Journal of Chest Surgery
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• v.32 no.8
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• pp.761-764
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• 1999

The glomus tumor is a distinctive benign neoplasm with a small painful nodule, occurs most commonly in extremities but may be found elsewhere in the body. Its occurrence in the trachea or lung parenchyme has been recognized with extreme rarity and there has not been any report, to our knowledge, of its occurrence in the main bronchial glomus tumor. We report a case of a glomus tumor in the left main bronchus in a 67-year-old man who was presented with blood-tinged sputum and dyspnea, which was completely relieved by surgical resection.

• Journal of Korea Multimedia Society
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• v.20 no.1
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• pp.43-50
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• 2017

According to living environment, the number of deaths due to thyroid diseases increased. In this paper, we proposed an algorithm for recognizing a thyroid detection using texture analysis based on shape, gray level co-occurrence matrix and gray level run length matrix. First of all, we segmented the region of interest (ROI) using active contour model algorithm. Then, we applied a total of 18 features (5 first order descriptors, 10 Gray level co-occurrence matrix features(GLCM), 2 Gray level run length matrix features and shape feature) to each thyroid region of interest. The extracted features are used as statistical analysis. Our results show that first order statistics (Skewness, Entropy, Energy, Smoothness), GLCM (Correlation, Contrast, Energy, Entropy, Difference variance, Difference Entropy, Homogeneity, Maximum Probability, Sum average, Sum entropy), GLRLM features and shape feature helped to distinguish thyroid benign and malignant. This algorithm will be helpful to diagnose of thyroid nodule on ultrasound images.