• The Transactions of the Korea Information Processing Society
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• v.7 no.4
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• pp.1184-1192
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• 2000

Multicast has communication mechanism that is able to transfer voice, video for only the specific user group. As compared to unicast, multicast is more susceptive to attack such as masquerading, malicious replay, denial of service, repudiation and traffic observation, because of the multicast has much more communication links than unicast communication. Multicast-specific security threats can affect not only a group's receivers, but a potentially large proportion of the internet. In this paper, we proposed the multicast security model that is able to secure multi-group communication in CBT(Core Based Tree), which is multicast routing. And designed the multicast key distribution protocol that can offer authentication, user privacy using core (be does as Authentication Server) in the proposed model.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04b
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• pp.713-716
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• 2001

여행자가 호텔에서나 회의실에서 인터넷에 접근하기 위하여 자신의 노트북을 이더넷 접속 포트에 연결할 때 이미 설정된 네트웍 파라미터를 변경하지 않고 Plug&Play 방식으로 접속할 수 있다면 매우 편리할 것이다. 기존의 DHCP, NAT 등의 프로토콜 등이 IP 주소가 설정되어 있지 않는 경우에 유용하나 설정된 주소 값을 변경없이 접근할 수 있도록 지원하지는 않는다. 본 논문에서는 Linux에서 지원하는 Masquerading 기능을 이용하여 Piug&Play 방식으로 네트웍에 접근하는 접속장치의 설계 및 구현을 기술한다.

• Journal of Veterinary Clinics
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• v.37 no.5
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• pp.282-285
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• 2020

A 14-year-old neutered-male Shih-Tzu was referred for glaucoma and hyphema accompanied by systemic hypertension. After topical corticosteroid and antiglaucoma medications, the left eye (OS) progressed phthisically, but ocular hypertension redevelop one-year-and-seven-months later. Suspected limbal melanoma developed in peripheral cornea/limbal sclera with heavily pigmented cornea OS. Ultrasound biomicroscopy and ocular ultrasonography differentiated ciliary body origin-heterogeneous mass from limbal mass. Persistent hyphema and pigmented cornea might obscure intraocular lesion and advanced diagnostic methods played a crucial role. Unlike the generally benign limbal melanoma, aggressive treatment was recommended for uveal tumor. Histopathology of enucleated OS confirmed malignant uveal melanoma with chronic hypertensive vasculopathy.

• Annals of Clinical Neurophysiology
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• v.18 no.1
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• pp.11-13
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• 2016

Idiopathic hypertrophic cranial pachymeningitis (ICHP) is diffuse inflammatory process of the dura mater. ICHP can produce similar presentation with Tolosa-Hunt syndrome (THS) if it involves cavernous sinus. A-29-year old male with persistent headache and no definite neurologic dysfunction was noted. Two weeks later, he complained of ophthalmoplegia, and his symptoms were thought to be manifestations of THS. Brain magnetic resonance images revealed diffuse thickened, enhanced pachymeninges in left tentorium. The patient was diagnosed with IHCP. We report a IHCP patient who showed very similar presentation as THS.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.3
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• pp.302-308
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• 1995

It is very difficult to differentiate the malignant tumor from the maxillofacial infections that have unclear cause, severe indurated swelling, pain and nonresponsiveness to antibioitic treatment and incision and drainage. Incisional biopsy, CT, and MRI examination may not distinguish between infection and a malignant tumors. And then, the clinicians can make a mistake that they perform a unnecessary radical surgery because of inaccurate diagnosis. We present three case reports of maxillofacial infectious disease with diagnosis process, treatment and differential diagnosis. The infectious disease were not resolved with antibiotic and surgical drainage. The progression of clinical sign and radiographic, indings of these disease were masqueraded as malignant tumors.

• Journal of Chest Surgery
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• v.49 no.5
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• pp.392-396
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• 2016

We report a case of aortic dissection masquerading as acute ischemic stroke followed by intravenous thrombolysis. A 59-year-old man presented with dizziness. After examination, the patient had a seizure with bilateral Babinski signs. Soon after identifying multiple acute infarctions in both hemispheres on diffusion-weighted brain magnetic resonance (MR) imaging, tissue plasminogen activator (t-PA) was administered. Both common carotid arteries were invisible on MR angiography, and subsequent chest computed tomography revealed an aortic dissection. The emergency operation was delayed for 13 hours due to t-PA administration. The patient died of massive bleeding.

• Clinics in Shoulder and Elbow
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• v.24 no.1
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• pp.32-35
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• 2021

Angioleiomyoma is a benign soft tissue tumor originating from vascular smooth muscle. We report a case of a 20-year-old student who presented with pain in the right shoulder of 4 years duration. Shoulder movements were pain-free throughout the range of motion except resisted external rotation. Magnetic resonance imaging visualized a well-circumscribed lesion over the infraspinatus tendon. The lesion was surgically removed and sent for histopathological analysis. Morphology and immunohistochemistry results were suggestive of angioleiomyoma. The most common location for such a lesion is the lower limb, with less than 1% being reported in the upper arm, of which an angioleiomyoma of the shoulder is extremely rare.

• Pediatric Infection and Vaccine
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• v.28 no.3
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• pp.168-172
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• 2021

Retroperitoneal infections are rarer than intra-abdominal infections in children; however, they can lead to significant morbidity in cases of missed diagnosis. We present a case of retroperitoneal abscess caused by extended-spectrum β-lactamase-producing Escherichia coli in a 10-year-old female adolescent who failed to show clinical improvement following empirical antibiotic therapy.

• Imaging Science in Dentistry
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• v.54 no.1
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• pp.105-107
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• 2024

The author herein presents an unusual case of eustachian tube calcification masquerading as loose radiopacities in the temporomandibular joints on a panoramic image, creating a diagnostic challenge. The patient, a 72-year-old woman, presented to the dental service for implant treatment to improve her masticatory function. A cone-beam computed tomography scan was performed and reviewed by a board-certified oral and maxillofacial radiologist. The scan showed no evidence of calcifications in the temporomandibular joints; however, it revealed nodular calcifications within the cartilaginous portion of the eustachian tube bilaterally. Additionally, this report briefly reviews the differential diagnosis of calcified loose bodies in the temporomandibular joint and provides information that needs to be reinforced periodically.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.26 no.3
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• pp.289-292
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• 2022

Cystic lesions of the liver are commonly encountered in routine clinical practice with a reported prevalence of 15%-18%. They may range from a benign simple developmental cyst to a malignancy. Therefore, an accurate diagnosis is essential for adequate management. Cystic tumors of the liver are classified based on the content (mucin containing or not), presence of ovarian stroma, and biliary communication. Biliary cystadenoma are a group of hepatobiliary neoplasia which by definition must be multilocular, lined by a columnar epithelium, and have a densely cellular ovarian stroma. We report a case of a cystic lesion in the hilar region of the liver, which had features of biliary cystadenoma on the preoperative imaging. However, on exploration was found to be a diverticular variant of type V choledochal cyst arising from both hepatic ducts. We have discussed the preoperative imaging features, intraoperative cholangiogram, and the management of this cystic lesion.