• Journal of Korean Neurosurgical Society
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• v.30 no.6
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• pp.769-773
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• 2001

Moyamoya disease is defined as the development of collateral pathways, associated with bilateral chronic progressive stenosis of the carotid fork. Persistent trigeminal artery is the vessel most frequently observed to persist into adult life among persistent carotid-basilar and carotid-vertebral anastomotic vessels. The authors present a man who had a sudden, severe headache and brain CT showed subarachnoid hemorrhage in left interpeduncular and prepontine cistern. Four-vessel angiogram revealed moyamoya disease associated with aneurysm arising from the junction of persistent trigeminal artery aneurysm and basilar artery. As a treatment, coil embolization was tried but it was failed because of anatomical difficulty of aneurysm. The aneurysm was successfully treated with clipping surgery 10 days later. To our knowledge, this is the first case being reported.

• Korean Journal of Computational Design and Engineering
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• v.11 no.1
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• pp.27-40
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• 2006

The exchange of parameterized feature-based CAD models is important for product data sharing among different organizations and automation systems. The role of feature-based modeling is to gonerate the shape of product and capture design intends In a CAD system. A feature is generated by referring to topological entities in a solid. Identifying referenced topological entities of a feature is essential for exchanging feature-based CAD models through a neutral format. If the CAD data contains the modification history in addition to the construction history, a matching mechanism is also required to find the same entity in the new model (post-edit model) corresponding to the entity in the old model (preedit model). This problem is known as the persistent naming problem. There are additional problems arising from the exchange of parameterized feature-based CAD models. Authors have analyzed previous studies with regard to persistent naming and characteristics for the exchange of parameterized feature-based CAD models, and propose a solution to the persistent naming problem. This solution is comprised of two parts: (a) naming of topological entities based on the object spore information (OSI) and secondary name (SN); and (b) name matching under the proposed naming.

• The Korean Journal of Pain
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• v.18 no.2
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• pp.222-225
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• 2005

Hiccups are due to an intermittent clonic spasm of the diaphragm. In most cases, hiccups are self-limiting disease, but persistent hiccups may be related to the presence of serious underlying systemic disease. Two patients who had persistent hiccups that were not controled by conventional methods and medications were referred to the pain clinic. We administered a single oral medication of gabapentin, and then the hiccups disappeared in both cases. We concluded that gabapentin should be considered as an alternative therapy to control persistent or intractable hiccup. It could be particularly useful for those patients with solid malignancies, either alone or as an "add-on therapy" with other oral agents.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.9B
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• pp.589-597
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• 2007

In this paper, a WDM metro ring consisting of access nodes with $FT-FR^n$ (Fixed Transmitter - n Fixed Receivers) is considered. A trade-off exists between node throughput and transmission fairness because the access nodes share wavelength channels. In order to eliminate the transmission unfairness and to increase throughput, the p-persistent medium access control (MAC) protocol is proposed: each node uses an empty optical slot to transmit a packet and make it available with the extraction of a transferred packet at the source access node, called source-stripping. The local empty slot can be used to transfer a head-of-line packet in the local buffer with probability p or it is used for the next downstream nodes with 1-p. The proposed MAC protocol provides better node throughput than the non-persistent protocol and exhibits better fairness index than the 1-persistent protocol in WDM ring networks. In addition, numerical analysis shows that the proposed MAC protocol maximizes the node throughput under uniform traffic conditions. For more detailed results, we use the network simulation under Poisson and self-similar traffic. Furthermore, unpredictable traffic constructed by the combination of the former and the latter is also considered. The reasonable probability of the p-persistent protocol for a given architecture can be determined through simulation.

• Journal of Sasang Constitutional Medicine
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• v.16 no.2
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• pp.105-113
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• 2004

1. Objectives Hiccup is one of common symptoms clinically and caused by various etiologies. Persistent hiccup is defined as hiccup lasting more than 48 hours. We have tried researching effect of herbal medicines(Dokhwaljihwang-tang, Yangkyuksanhwa-tang). 2. Methods To heal the persistent hiccup, we used Dokhwaljihwang-tang and Yangkyuksanhwa-tang. 3. Results A Soyangin patient diagnosed to have persistent hiccup was, treated with Soyangin herbal medicines (Dokhwaljihwang-tang and Yangkyuksanhwa-tang), and change of his symptom & general condition was managed. 4. Conclusions The constitutional treatment with Soyangin herbal medicines(Dokhwaljihwang-tang, Yangkyuksanhwa-tang) may have an effect on management of persistent hiccup. Further study on management of this disease is needed.

• Computers and Concrete
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• v.17 no.6
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• pp.723-737
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• 2016

In this paper an approach was described for determination of direction of sliding block in rock slopes containing planar non-persistent open joints. For this study, several gypsum blocks containing planar non-persistent open joints with dimensions of $15{\times}15{\times}15cm$ were build. The rock bridges occupy 45, 90 and $135cm^2$ of total shear surface ($225cm^2$), and their configuration in shear plane were different. From each model, two similar blocks were prepared and were subjected to shearing under normal stresses of 3.33 and $7.77kg/cm^{-2}$. Based on the change in the configuration of rock-bridges, a factor called the Effective Joint Coefficient (EJC) was formulated, that is the ratio of the effective joint surface that is in front of the rock-bridge and the total shear surface. In general, the failure pattern is influenced by the EJC while shear strength is closely related to the failure pattern. It is observed that the propagation of wing tensile cracks or shear cracks depends on the EJC and the coalescence of wing cracks or shear cracks dominates the eventual failure pattern and determines the peak shear load of the rock specimens. So the EJC is a key factor to determine the sliding direction in rock slopes containing planar non-persistent open joints.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.25 no.4
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• pp.296-311
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• 2021

Topological Data Analysis (TDA), a relatively new field of data analysis, has proved very useful in a variety of applications. The main persistence tool from TDA is persistent homology in which data structure is examined at many scales. Representations of persistent homology include persistence barcodes and persistence diagrams, both of which are not straightforward to reconcile with traditional machine learning algorithms as they are sets of intervals or multisets. The problem of faithfully representing barcodes and persistent diagrams has been pursued along two main avenues: kernel methods and vectorizations. One vectorization is the Betti sequence, or Betti curve, derived from the persistence barcode. While the Betti sequence has been used in classification problems in various applications, to our knowledge, the stability of the sequence has never before been discussed. In this paper we show that the Betti sequence is unstable under the 1-Wasserstein metric with regards to small perturbations in the barcode from which it is calculated. In addition, we propose a novel stabilized version of the Betti sequence based on the Gaussian smoothing seen in the Stable Persistence Bag of Words for persistent homology. We then introduce the normalized cumulative Betti sequence and provide numerical examples that support the main statement of the paper.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.203-205
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• 2022

As digital transformation and remote work environment advanced by Covid-19 become more common, the scale of leakage damage to industrial secrets and personal information caused by information leakage attacks is increasing. Recently, advanced and persistent information leakage attacks have become a serious security threat because they do not quickly leak large amounts of information, but continuously leak small amounts of information over a long period of time. In this study, we propose a framework for detecting advanced and persistent information leakage attacks based on traffic characteristics. The proposed method can effectively detect advanced and persistent information leakage attacks using traffic patterns, packet sizes, and metadata, even if the payload is encrypted.

• Progress in Superconductivity and Cryogenics
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• v.11 no.1
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• pp.30-34
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• 2009

This paper deals with charging and persistent-current mode operating characteristics of BSCCO magnet load using high-temperature superconducting (HTS) power supply. The HTS power supply consists of two heater-triggered switches, an iron-core transformer with the primary copper winding and the secondary BSCCO solenoid, and a BSCCO magnet load. The magnet load was fabricated by double pancake winding and its inductance is about 21 mH. A hall sensor was installed at the middle of the magnet load to measure the current in the load. In order to investigate the efficient pumping characteristics, operating tests of heater-triggered switch with respect to dc heater current were carried out, and the electromagnet current was determined by considering saturation characteristics of its iron core. The saturation characteristics of charged current in the magnet load were observed with respect to various pumping periods: 12 s, 14 s, 24 s and 32 s. After charging the magnet load, the persistent current was measured. The operating characteristics of the persistent current mode were mainly determined by joint resistance and magnet load.

• Restorative Dentistry and Endodontics
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• v.47 no.3
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• pp.26.1-26.10
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• 2022

Wegener's granulomatosis (WG) is a condition with immune-mediated pathogenesis that can present oral manifestations. This report describes the case of a patient diagnosed with WG 14 years previously, who was affected by persistent pain of non-odontogenic origin after successful endodontic treatment. A 39-year-old woman with WG was diagnosed with pulp necrosis and apical periodontitis of teeth #31, #32, and #41, after evaluation through a clinical examination and cone-beam computed tomography (CBCT). At the first appointment, these teeth were subjected to conventional endodontic treatment. At 6- and 12-month follow-up visits, the patient complained of persistent pain associated with the endodontically treated teeth (mainly in tooth #31), despite complete remission of the periapical lesions shown by radiographic and CBCT exams proving the effectiveness of the endodontic treatments, thus indicating a probable diagnostic of persistent pain of non-odontogenic nature. After the surgical procedure was performed to curette the lesion and section 3 mm of the apical third of tooth #31, the histopathological analysis suggested that the painful condition was likely associated with the patient's systemic condition. Based on clinical, radiographic, and histopathological findings, this unusual case report suggests that WG may be related to non-odontogenic persistent pain after successful endodontic treatments.