• Journal of Korean Neurosurgical Society
• /
• 제60권5호
• /
• pp.511-517
• /
• 2017

Objective : Spontaneous intracerebral hemorrhage (ICH) and ischemic stroke share common vascular risk factors such as aging and hypertension. Previous studies suggested that the rate of recurrent ICH and ischemic stroke might be similar after ICH. Presence of cerebral arterial stenosis is a potential risk factor for future ischemic stroke. This study investigated the prevalence and factors associated with cerebral arterial stenosis in Korean patients with spontaneous ICH. Methods : A total of 167 patients with spontaneous ICH were enrolled. Intracranial arterial stenosis (ICAS) and extracranial arterial stenosis (ECAS) were assessed by computed tomography angiography. Presence of ICAS was defined if patients had arterial stenosis in at least one intracranial artery. ECAS was assessed in the extracranial carotid artery. More than 50% luminal stenosis was defined as presence of stenosis. Prevalence and factors associated with presence of ICAS and cerebral arterial stenosis (presence of ICAS and/or ECAS) were investigated by multivariable logistic regression analysis. Results : Thirty-two (19.2%) patients had ICAS, 7.2% had ECAS, and 39 (23.4%) patients had any cerebral arterial stenosis. Frequency of ICAS and ECAS did not differ among ganglionic ICH, lobar ICH, and brainstem ICH. Age was higher in patients with ICAS ($67.6{\pm}11.8$ vs. $58.9{\pm}13.6years$ p=0.004) and cerebral arterial stenosis ($67.9{\pm}11.6$ vs. $59.3{\pm}13.5years$, p<0.001) compared to those without stenosis. Patients with ICAS were older, more frequently had diabetes, had a higher serum glucose level, and had a lower hemoglobin level than those without ICAS. Patients with cerebral arterial stenosis were older, had diabetes and lower hemoglobin level, which was consistent with findings in patients with ICAS. However, patients with cerebral arterial stenosis showed higher prevalence of hypertension and decreased kidney function compared to those without cerebral arterial stenosis. Multivariable logistic regression analyses showed that aging and presence of diabetes independently predicted the presence of ICAS, and aging, diabetes, and hypertension were independently associated with presence of cerebral arterial stenosis. Conclusion : 19.2% of patients with spontaneous ICH had ICAS, but the prevalence of ECAS was relatively lower (7.2%) compared with ICAS. Aging and diabetes were independent factors for the presence of ICAS, whereas aging, hypertension, and diabetes were factors for the cerebral arterial stenosis.

• Korean Journal of Radiology
• /
• 제20권5호
• /
• pp.739-748
• /
• 2019

For recanalization of emergent large vessel occlusions (ELVOs), endovascular therapy (EVT) using newer devices, such as a stent retriever and large-bore catheter, has shown better patient outcomes compared with intravenous recombinant tissue plasminogen activator only. Intracranial atherosclerotic stenosis (ICAS) is a major cause of acute ischemic stroke, the incidence of which is rising worldwide. Thus, it is not rare to encounter underlying ICAS during EVT procedures, particularly in Asian countries. ELVO due to underlying ICAS is often related to EVT procedure failure or complications, which can lead to poor functional recovery. However, information regarding EVT for this type of stroke is lacking because large clinical trials have been largely based on Western populations. In this review, we discuss the unique pathologic basis of ELVO with underlying ICAS, which may complicate EVT procedures. Moreover, we review EVT data for patients with ELVO due to underlying ICAS and suggest an optimal endovascular recanalization strategy based on the existing literature. Finally, we present future perspectives on this subject.

• 한국추진공학회지
• /
• 제23권4호
• /
• pp.98-103
• /
• 2019

함정 운용 장비의 건전성 예측은 유지보수의 효율성 및 긴박한 상황에서의 운용성능 유지를 위한 필수 요소이다. 최근 함정의 양적인 증가와 작전반경 확대에 따라 운용성능 유지를 위해 통합조건평가시스템(ICAS)을 도입하여 운용중이며, 관련기술 국산화를 위해 다각도로 연구가 진행되고 있다. 본 논문에서는 함정 운용 장비인 디젤발전기의 건전성 예측방법 중 데이터기반 모델 적용에 대한 결과를 제시 하였다.

• 대한금속재료학회지
• /
• 제47권7호
• /
• pp.447-453
• /
• 2009

Isotropic conductive adhesives (ICAs) have been used or considered as an interconnect material for radio frequency identification (RFID) inlays or other flip chip assemblies due to the advantages of having a low temperature and high-speed bonding. In this work, the curing properties of commercial ICAs for the RFID tag application and the signal transmission in conductive lines that contained the ICA joints were evaluated as a function of the degree of cure at 900 MHz frequency range. The ICAs showed adequate signal transmission only after the curing process passed over the critical time. It was also found that the insertion loss of signal was more dependent on the contact states of Ag fillers in the bondline in preference to the electrical resistance of the ICA itself.

• 정보처리학회논문지B
• /
• 제11B권4호
• /
• pp.429-436
• /
• 2004

본 논문에서는 침도를 추가한 뉴우턴법과 할선법에 기초한 고정점 알고리즘의 독립성분분석을 각각 제안하였다. 여기서 첨도의 추가는 유사한 속성을 가지는 성분의 군집화된 분석순서를 얻기 위함이고, 고정점 알고리즘은 학습파라미터와 무관한 빠른 성분분석과 우수한 분석성능을 얻기 위함이다. 제안된 두 가지 독립성분분석 각각을 500개 샘플을 가지는 6개의 혼합신호와 $512\times512$ 픽셀을 가지는 10개의 혼합영상 분리에 각각 적용한 결과, 제안된 두 가지 기법은 항상 일정한 분석순서를 유지하여 첨도가 추가되지 않은 기존의 기법들에서 알고리즘의 수행 때마다 랜덤하게 변하는 분석순서의 제약을 해결할 수 있었다. 특히 군집화의 속성을 가진 제안된 독립성분분석들은 신호나 영상의 분류나 식별에도 적용할 수 있다. 한편 할선법의 제안된 기법이 뉴우턴법의 제안된 기법보다 빠르면서도 우수한 분리성능이 있음을 확인하였다.

• Journal of Korean Neurosurgical Society
• /
• 제49권5호
• /
• pp.287-289
• /
• 2011

Thalamoperforating artery aneurysms are rarely reported in the literature. We report an extremely rare case of ruptured distal anterior thalamoperforating artery aneurysm which was treated by endovascular obliteration in a patient with occlusion of both the internal carotid arteries (ICAs) : A 72-year-old woman presented with severe headache and loss of consciousness. Initial level of consciousness at the time of admission was drowsy and the Glasgow Coma Scale score was 14. Brain computed tomography (CT) scan was performed which revealed intracerebral hemorrhage in right basal ganglia, subarachnoid hemorrhage, and intraventricular hemorrhage. The location of the aneurysm was identified as within the globus pallidus on CT angiogram. Conventional cerebral angiogram demonstrated occlusion of both the ICAs just distal to the fetal type of posterior communicating artery and the aneurysm was arising from right anterior thalamoperforating artery (ATPA). A microcatheter was navigated into ATPA and the ATPA proximal to aneurysm was embolized with 20% glue. Post-procedural ICA angiogram demonstrated no contrast filling of the aneurysm sac. The patient was discharged without any neurologic deficit. Endovascular treatment of ATPA aneurysm is probably a more feasible and safe treatment modality than surgical clipping because of the deep seated location of aneurysm and the possibility of brain retraction injury during surgical operation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제12권11호
• /
• pp.5465-5480
• /
• 2018

Energy-efficient task scheduling on multi-core server is a fundamental issue in green cloud computing. Multi-core processors are widely used in mobile devices, personal computers, and servers. Existing energy efficient task scheduling methods chiefly focus on reducing the energy consumption of the processor itself, and assume that the cores of the processor are controlled independently. However, the cores of some processors in the market are divided into several voltage islands, in each of which the cores must operate on the same status, and the cost of the server includes not only energy cost of the processor but also the energy of other components of the server and the cost of user waiting time. In this paper, we propose a cost-aware scheduling algorithm ICAS for computation intensive tasks on multi-core server. Tasks are first allocated to cores, and optimal frequency of each core is computed, and the frequency of each voltage island is finally determined. The experiments' results show the cost of ICAS is much lower than the existing method.

• Investigative Magnetic Resonance Imaging
• /
• 제25권3호
• /
• pp.193-196
• /
• 2021

Congenital absence of the bilateral internal carotid arteries (ICA) is a very rare occurrence. Recognition of this rare anomaly is important, when considering intracranial endovascular interventions in the event of thromboembolic events with revascularization, transsphenoidal surgery, and the surveillance and detection of associated cerebral aneurysms. We report a case of a 25-year-old man who presented with headache since 2 years ago, and was incidentally discovered to have a congenital bilateral absence of ICAs.

• 한국중재학회지:중재연구
• /
• 제28권1호
• /
• pp.43-75
• /
• 2018

The Court of Arbitration for Sport (CAS) was created to focus on the procedural complexity in the resolution of sports-related disputes, confidentiality, the matter of expenses, and the necessity of prompt settlement in the field of international sports. The CAS had originally launched as one of bodies of International Olympic Committee (IOC), but later it became properly operational as an independent organization to facilitate sports-related disputes when the International Council of Arbitration for Sport (ICAS), which came into force in accordance with the Paris Agreement in 1984 and has acted in place of IOC, took responsibility for the administration and financing of the CAS. The CAS is composed of four divisions, the Ordinary Arbitration Division and the Appeals Arbitration Division, the Ad hoc Division created later in 1996 and the CAS Anti-Doping Division (CAS ADD) established as from 2016 only to conduct proceedings and to issue decisions on an alleged anti-doping rule violation, and two (Sydney and New York) permanent decentralized offices. The head office of the CAS is Lausanne, Switzerland. Since CAS ADD was established, CAS Ad hoc Division has had jurisdiction over the appeal case against a decision pronounced by the IOC, an NOC, an international Federation or an Organizing Committee for the Olympic Games. Although there are so many virtues of CAS as a resolution authority for sports-related disputes in terms of its organization, arbitration rules and procedures, it is also true that the CAS has not been showing the consistency. The CAS should overcome these issues through much more advanced system and its instant and fair decisions.

• 대한의용생체공학회:의공학회지
• /
• 제30권5호
• /
• pp.373-380
• /
• 2009

In general, Independent component analysis (ICA) is a statistical blind source separation technique, used either in spatial or temporal domain. The spatial or temporal ICAs are designed to extract maximally independent sources in respective domains. The underlying sources for spatiotemporal data (sequence of images) can not always be guaranteed to be independent, therefore spatial ICA extracts the maximally independent spatial sources, deteriorating the temporal sources and vice versa. For such data types, spatiotemporal ICA tries to create a balance by simultaneous optimization in both the domains. However, the spatiotemporal ICA suffers the problem of source ambiguity. Recently, constrained ICA (c-ICA) has been proposed which incorporates a priori information to extract the desired source. In this study, we have extended the c-ICA for better analysis of spatiotemporal data. The proposed algorithm, i.e., constrained spatiotemporal ICA (constrained st-ICA), tries to find the desired independent sources in spatial and temporal domains with no source ambiguity. The performance of the proposed algorithm is tested against the conventional spatial and temporal ICAs using simulated data. Furthermore, its performance for the real spatiotemporal data, functional magnetic resonance images (fMRI), is compared with the SPM (conventional fMRI data analysis tool). The functional maps obtained with the proposed algorithm reveal more activity as compared to SPM.