• Journal of Internet Computing and Services
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• v.17 no.2
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• pp.19-28
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• 2016

Internet traffic has been significantly increasing due to the development of information and communication networks and the growing numbers of cell phone users that access networks. This paper connects to this issue by presenting a way to detect and analyze a typical DDoS attack that results in Internet breaches and network attacks, which are on the increase. To achieve this goal, we improve features and GUI of the existing ATMSim analysis package and use it. This package operates on a network flow-based analysis method, which means that normal traffic collected through an internal LAN at the Korean Bible University campus as well as anomaly traffic with DDoS attacks are generated. Self-similarity processes are used to analyze normal and anomaly traffic that are collected and generated from the improved ATMSim. Our numerical results obtained from three Hurst parameter estimate techniques show that there is quantitatively a significant difference between normal traffic and anomaly traffic from a self-similarity perspective.

• The Journal of Internal Korean Medicine
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• v.26 no.1
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• pp.213-220
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• 2005

Objective : Thyroid diseases are one of the most common endocrine disorders. However, the first chosen-treatments including anti-thyroidal and hormone-supplement therapy in western medicines, sometimes have failed to improve abnormal thyroid hormone secretions and clinical symptoms. Therefore, there has been a growing expectation for Oriental Medicine to take the role of alternative therapy. However, there has been little analysis of clinical characteristics. In this study, clinical characteristics of thyroidal disease patients who visited Kyung-Hee oriental hospital from January to July 2004 were analyzed. Methods : A total 86 patients diagnosed as hyperthyroidism, hypothyroidism or thyroid nodule were selected. Clinical history, including sex, age, symptoms, disease duration and methods of previous therapy and thyroidal test, such as thyroid function test (TFT), thyroid scan and other thyroid examinations. Results : In distribution of onset age and sex, the patients who have visited oriental hospital with thyroidal diseases showed similar characteristics with typical patients. In clinical symptom, the most frequent clinical sign was fatigue in both hyperthyroidism and hypothyroidism, which differs from the classical characteristics of those diseases. Most patients complained the unresolved symptoms, some of which are attributable to abnormal thyroid hormone secretions, in spite of western therapy with anti-thyroidal and hormone supplement agents. Conclusions : In oriental therapy, it will be necessary to consider the unique clinical features of thyroidal diseases different from classical patterns, and this study suggests that oriental therapy is a good alternative method for patients whose first treatment with western agents failed. Furthermore, more public information to these patients about oriental medicine would be helpful to increase cure rates, and give various choices to patients with thyroid diseases.

• Korean Journal of Head & Neck Oncology
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• v.17 no.1
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• pp.26-31
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• 2001

Background: Primary malignant lymphoma of the parotid gland is a rare disease and defined as any malignant lymphoma that first manifests in the parotid gland, regardless of the subsequent stage of the diseases, whether it arises in the parenchyma or intraglandular lymph nodes. This study was performed to review the clinicopathological characteristics of primary parotid lymphoma and identify its optimal treatment modality. Materials and Methods: Six cases with parotid mass as first presentation of malignant lymphoma between 1988 and 2000, were studied on the basis of clinical features, diagnostic tools, treatment modality, treatment outcomes, and clinical stage by Ann Arbor Criteria. All were microscopically reevaluated and classified by NCI working formulation. Results: All patients were males and mean age was 36.7 years (2-66 years). Rapid growing non-tender mass was presented in all the cases and cervical lymphnodes were palpated in 4 cases. However, there was not any evidence of concurrent autoimmune disease such as Sjogren's syndrom or Rheumatoid arthritis. One case was confirmed by surgical specimen after superficial parotidectomy, 2 by excisional biopsy, and 3 by incisional biopsy. The stage of disease by NCI working formulation was IE in 1 patient, IIE in 4 and IV in 1. All were classified into non-Hodgkin' lymphoma, of which there were 5 cases of B-cell type and 1 case of T-cell type. There were 3 diffuse large cell lymphomas, 1 Burkitt lymphoma, 1 MALT lymphoma and 1 T-lymphoblastic lymphoma. Three cases were treated by chemotherapy only, 2 by radiotherapy only and 1 by chemo-radiotherapy. One case with Burkitt lymphoma was died from the disease and one case was lost to follow-up. The others are alive with no evidence of recurrence. Conclusions: Although primary parotid lymphoma is rare and difficult to diagnose preoperatively, most were detected in early stage and showed a relatively good response to the chemotherapy or radiotherapy like other types of extranodal malignant lymphoma.

• Applied Microscopy
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• v.35 no.2
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• pp.97-104
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• 2005

Plant epidermis consists of relatively unspecialized cells and more specialized cells of various structure and function. Trichomes are specialized cells originated from the epidermis and much attention has been paid to the plants developing trichomes with peculiar structure and function. The present study has been undertaken to examine the trichome type noticed in the leaf epidermis of Althaea rosea using scanning electron microscopy. Four types, namely simple, short-and long-tufted, and glandular hairs, were detected in their epidermis. Their Distribution, frequency and structure varied by the development and epidermal surface. The most frequently distinguished type was the tufted ones growing in young leaves of the abaxial epidermis, while the simple hairs were rare throught the examination. The short-tufted hairs branched up to seven times having each branchlet about $160{\sim}210{\mu}m$ in length at maturity. The long-tufted hairs exhibited up to ten branchlets, where branchlets could reach up to $900{\sim}1,000{\mu}m$ long when fully expanded. Glandular trichome was the peltate type comprising $1{\sim}2$ secretory head cells, 2 stalk cells and a basal cell. The short peltate glandular hairs, usually not exceeding $40{\mu}m$, differentiated more along the areoles in the adaxial epidermis. The function of these trichomes in A. rosea has been still obscure, but it has been speculated that they probably play a role in protection; non-glandular ones possibly providing a defense against insects and secretory glandular type participating in chemical defense. Structural features of these trichomes at cellular level will be discussed in the following study of transmission electron microscopy.

• Journal of Korea Water Resources Association
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• v.46 no.4
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• pp.425-437
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• 2013

This study performed the bivariate drought frequency analysis for duration and severity of drought, using copula functions which allow considering the correlation structure of joint features of drought. We suggested the confidence intervals of duration-severity-frequency (DSF) curves for the given drought duration using stochastic scheme of monthly rainfall generation for 57 sites in Korea. This study also investigated drought risk via illustrating the largest drought events on record over 50 and 100 consecutive years. It appears that drought risks are much higher in some parts of the Nakdong River basin, southern and east coastal areas. However, such analyses are not always reliable, especially when the frequency analysis is performed based on the data observed over relatively short period of time. To quantify the uncertainty of drought frequency curves, the droughts were filtered by different durations. The 5%, 25%, 50%, 75%, and 95% confidence intervals of the drought severity for a given duration were estimated based on the simulated rainfall time series. Finally, it is shown that the growing uncertainties is revealed in the estimation of the joint probability using the two marginal distributions since the correlation coefficient of two variables is relatively low.

• Sijohaknonchong
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• v.20
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• pp.75-96
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• 2004

A pavilion is located in the place with beautiful scenery, which maximizes the poetical features of nature. So a scholar in the Chosun Dynasty had the dream of possessing it. This trends of the Chosun scholar resulted in producing lots of literary works related with the pavilion. In this thesis, I researched the characters of Pavilion Si-Jo in accordance with the function of pavilion. First, the pavilion, which is surrounded by the beautiful scenery, is a good place to see the beauty of nature. It is needless to walk around to see the scenery thanks to its open structure. So the feeling in the pavilion Si-Jo is distinguished from other sightseeing Si-Jos: those show the way of seeing the scenery walking here and there, but this shows the way of seeing the scenery only just looking up, looking down, and looking in the distance. Second, the pavilion functions as an academic place. In this case, it can be said that it functions like a lecture hall. It is more effective to study in the pavilion than in the closed structure, a lecture hall. Furthermore, the scholar studying in the pavilion understand the principle of nature with seeing the beautiful mountain and river, and it can be a place for growing a vast-flowing spirit. This kind of poetry has been handed down with the Chinese poetry, and the character who operated the pavilion often appears in the work. Third, the pavilion functions as a space for a fraternity or poetry circles. The poetic exchange was conducted by host of pavilion. which is the key ingredient for organizing a poetry circles. Finally, the pavilion functions as an entertainment. Although it is a space for an entertainment, there is no deviation as a man of novel birth. If the pavilion has the feature of closeness, there are sometimes works which shows the deviation of them.

• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.83-91
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• 2014

The problems of environmental pollutions and resources depletion have been growing issues in global construction recently. Efforts to reduce $CO_2$ emission have been also made in all sectors of construction industry these days. As one of the biggest industries that consume a huge amount of resources and generate complex construction wastes, the construction industry has significant impacts on environment issues. However, systematic approach to manage wastes has been rarely made, and most construction wastes from construction sites are being land-filled or incinerated. In this study, a system is proposed to predict the amount of wastes in visual formats, and to control the process of wastes management. The system's main functions include : (1) to estimate the amount of wastes to be generated in project schedule, (2) to categorize the types of wastes, (3) to determine the timing of taking out wastes from sites, and (4) to share information regarding wastes for recycling. A huge amount of wastes are generated in construction process, but most of the wastes have been discharged in forms of mixed wastes, which make them hardly reused. The system not only provide information on wastes to be generated, but also prevent mixing various wastes by classifying them by types and schedules. This features of the system, along with functions to share wastes information with other agencies outside the site, are expected to enhance the level of wastes recycling to a great extent. By saving construction materials through wastes recycling, the system also contributes in reducing $CO_2$ emission.

• The Transactions of the Korea Information Processing Society
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• v.4 no.10
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• pp.2615-2628
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• 1997

In this paper, a new codebook design algorithm is proposed. It uses a DCT map based on two-dimensional discrete cosine of transform (2D DCT) and finite state vector quantizer (FSVQ) when the vector quantizer is designed for image transmission. We make the map by dividing input image according to edge quantity, then by the map, the significant features of training image are extracted by using the 2D DCT. A master codebook of FSVQ is generated by partitioning the training set using binary tree based on tree-structure. The state codebook is constructed from the master codebook, and then the index of input image is searched at not master codebook but state codebook. And, because the coding of index is important part for high speed digital transmission, it converts fixed length codes to variable length codes in terms of entropy coding rule. The huffman coding assigns transmission codes to codes of codebook. This paper proposes single-side growing huffman tree to speed up huffman code generation process of huffman tree. Compared with the pairwise nearest neighbor (PNN) and classified VQ (CVQ) algorithm, about Einstein and Bridge image, the new algorithm shows better picture quality with 2.04 dB and 2.48 dB differences as to PNN, 1.75 dB and 0.99 dB differences as to CVQ respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.14-15
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• 2010

Recently there has been growing interest in topological insulators or the quantum spin Hall (QSH) phase, which are insulating materials with bulk band gaps but have metallic edge states that are formed topologically and robust against any non-magnetic impurity [1]. In a three-dimensional material, the two-dimensional surface states correspond to the edge states (topological metal) and their intriguing nature in terms of electronic and spin structures have been experimentally observed in bulk Bi1-xSbx single crystals [2,3,4]. However, if we want to know the transport properties of these topological metals, high purity samples as well as very low temperature will be needed because of the contribution from bulk states or impurity effects. In a recent report, it was also shown that an intriguing coupling between the surface and bulk states will occur [5]. A simple solution to this bothersome problem is to prepare a topological metal on an ultrathin film, in which the surface-to-bulk ratio is drastically increased. Therefore in the present study, we have investigated if there is a method to make an ultrathin Bi1-xSbx film on a semiconductor substrate. From reflection high-energy electron diffraction observation, it was found that single crystal Bi1-xSbx films (0${\sim}30\;{\AA}A$ can be prepared on Si(111)-$7{\times}7$. The transport properties of such films were characterized by in situ monolithic micro four-point probes [6]. The temperature dependence of the resistivity for the x=0.1 samples was insulating when the film thickness was $240\;{\AA}A$. However, it became metallic as the thickness was reduced down to $30\;{\AA}A$, indicating surface-state dominant electrical conduction. Figure 1 shows the Fermi surface of $40\;{\AA}A$ thick Bi0.92Sb0.08 (a) and Bi0.84Sb0.16 (b) films mapped by angle-resolved photoemission spectroscopy. The basic features of the electronic structure of these surface states were shown to be the same as those found on bulk surfaces, meaning that topological metals can be prepared at the surface of an ultrathin film. The details will be given in the presentation.

• Journal of Veterinary Clinics
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• v.32 no.4
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• pp.301-307
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• 2015

The purpose of this study was to compare echocardiographic parameters of cloned beagle dogs with the previously reported reference range. Seven cloned dogs were assessed for anatomical features and cardiac function through left- and right-sided heart and right ventricle outflow tract from M-mode, 2D-mode, pulsed wave Doppler and tissue Doppler imaging. In all the cloned dogs, there were no abnormalities in anatomical structure and measurements were within the normal reference range. In addition, left- and right-sided myocardial function was within the normal reference range. Especially, pulmonary hypertension and right-sided heart failure frequently encountered in cloned animals were not recognized in cloned dogs. In conclusion, no evidence of cardiovascular dysfunction in mature cloned dogs could be identified either at birth or the growing stage in this study. Therefore, serious adverse effects of somatic cell nuclear transfer technology including transgenesis on cardiac morphology and function were not found in cloned dogs.