• Journal of electromagnetic engineering and science
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• 제6권1호
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• pp.62-70
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• 2006

This paper presents a new power plane design method incorporating a single geometry derived from a unit cell of photonic bandgap(PBG) structure. This method yields constantly wide suppression of parallel plate resonances from 0.9 GHz to 4.2 GHz and is very efficient to eliminate PCB resonances in a specified frequency region to provide effective suppression of simultaneous switching noise(SSN). It is shown that with only two cells the propagation of unwanted high frequency signals is effectively suppressed, while it could provide continuous return signal path. The measured results agree very well with theoretically predicted ones, and confirm that proposed method is effective for reducing EMI, with measured near-field distribution. The proposed topology is suitable for design of high speed digital system.

• 고신대학교 의과대학 학술지
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• 제33권2호
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• pp.257-262
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• 2018

Guillain-$Barr{\acute{e}}$ syndrome (GBS) and acute disseminated encephalomyelitis (ADEM) are demyelinating neurologic disorders with different target organs. Although they share similar pathogenetic mechanism, reports of simultaneous occurrence of the 2 disorders are rare. A 2 year 6 month old girl visited our hospital for fever, cough, and general weakness. Although the muscle power of extremities showed mild weakness and voiding difficulty, initial deep tendon reflex of both knees and ankles was normal. A nerve conduction study to evaluate the weakness revealed the absence of F waves. Cerebrospinal fluid analysis demonstrated pleocytosis with lymphocyte predominance and elevated protein levels. Magnetic resonance imaging showed abnormal T2 hyperintensity in pons, medulla and spinal cord. Serum anti-GD1b antibody was positive. Based on clinical findings, laboratory findings, nerve conduction study, and neuroimaging, the diagnosis of GBS and ADEM was made. This is the first case of GBS accompanied by ADEM in Korea.

• 비교문화연구
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• 제23권
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• pp.295-319
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• 2011

This study examines how Latinidad can be reclaimed as a site for exploring affinities of Latinos in Latin music industry, especially from the 90s. By looking at sites where Latinidad is constituted, such as the case of Jennifer $L{\acute{o}}pez$ becoming Selena, it intends to suggest that the concept can be deployed as a political bridge to connect latinos. And by examining Cuban-American artists' self identification in Latin Grammy Awards, it reveals that the latin music business definitions of Latinidad is coded differently for them as 'Caribbean' to erase a natural resonance of Cuba. In addition, by dealing with Shakira's somewhat contradictory representation of Colombianidad, the study argues that Latinidad serves as a social construct and newly emerges as a convenient interstitial place between the Latin American and the US Latino. Shakira's case serves to show how the transnational trends of latin music contribute to create a simultaneous sense of Latinidad and Colombianidad. Focusing on the commercial significance of understanding of what latino is or should be, this paper aims to interrogate current understandings of Latinidad in the realm of latin music and popular culture.

• 전력전자학회논문지
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• 제24권2호
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• pp.84-91
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• 2019

This study proposes a AC/DC railway vehicle control algorithm that enables simultaneous driving of AC and DC power supply sections. In the Seoul metropolitan region, trolley voltage for railway vehicle is divided into AC and DC power supplies. Therefore, AC/DC railway vehicle algorithm is essential for driving on the outskirts of the region. This study analyzes resonance and beat phenomena for simultaneously running in AC and DC power supply sections, and proposes a control algorithm for railway vehicles with the application of damping and beatless controls based on this analysis. The performance of the proposed algorithm is verified by simulation and analysis of actual driving results.

• 대한관절경학회지
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• 제14권1호
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• pp.25-28
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• 2010

대부분의 반월상 연골의 양동이 손잡이형 파열은 전방 십자인대와 동반하여 발생하며, 전방십자 인대의 급성 손상 시는 외측 반월상 연골의 양동이 손잡이형 파열이 흔한 반면 만성 전방 십자인대 손상 시는 내측에서 흔히 발생한다고 보고된다. 저자들은 전방십자 인대의 불안정성과 동반 된 내,외측 반월상 연골의 동시적 양동이 손잡이형 파열에 대해 보고하고자 한다.저자들은 전방십자 인대의 불안정성과 동반 된 내,외측 반월상 연골의 동시적 양동이 손잡이형 파열의 발생 가능성에 대한 인식을 높이고자 하였으며, 추가적으로 본 손상의 발생기전, 임상증상, 자기공명영상 검사상 특이 소견 및 치료에 대해 문헌 고찰과 함께 보고하고자 한다.

• 치과방사선
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• 제29권1호
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• pp.341-355
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• 1999

Squamous cell carcinoma is the most common type of oral cancer and odontogenic myxoma is relatively uncommon benign tumor of mesenchymal origin. There are, to our knowledge, no prior reports of simultaneously occurring squamous cell carcinoma and odontogenic myxoma of the jaw bones. In this case, at first, the plain films and computed tomograms revealed a large expansile multilocular radiolucent lesion on left mandible and marked expansion of cortical plate. In addition this radiograms revealed also infiltrative bony destruction of anterior and medial border of ascending ramus of left mandible and alveolar bone of left maxilla, floating teeth on left lower molar area and metastatic enlargement of left submandibular, jugular digastric and spinal accessory lymphnodes. Magnetic resonance imaging of this patient revealed infiltrative growth of tumor on alveolar bone of left maxilla, left retromolar fat pad. left masseter and left medial pterygoid muscle. Intraoral presurgical biopsy presented typical features of squamous cell carcinoma. After chemotherapy with radiation therapy during 6 months. this central lesion was diagnosed as odontogenic myxoma by the postsurgical biopsy. After 3 months, this patient presented multiple metastatic signs at lumbar spines, rib and liver. Consequently, our case is simultaneous occurrence of squamous cell carcinoma and odontogenic myxoma.

• 한국전자파학회논문지
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• 제18권2호
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• pp.206-212
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• 2007

본 논문에서는 넓은 영역에서 GBN/SSN 억제 특성을 보이는 이종 셀 EBG 구조를 이용한 새로운 전원면 구조를 제안하였다. 제안된 구조는 -30 dB 이하의 삽입 손실로 정의되는 저지 대역이 GBN의 에너지가 집중적으로 분포하는 수 백 MHz에서 시작하며 약 7.9 GHz의 넓은 대역폭을 갖는다. 본 구조의 특징은 인덕턴스를 강화하는 나선형 연결 선로와 분산적 LC 회로의 주기를 줄이는 이종 셀을 추가한 것이다. 그 결과 -30 dB 저지 대역의 저주파에서의 차단 주파수가 낮아짐은 물론 대역폭이 넓어진 특성을 보였다. 또한, 전원면과 접지면 사이의 구조적 공진 모드가 현격히 억제되었으며 평행판 도파관에 비해 낮은 EMI 특성을 보였다.

• 청정기술
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• 제27권4호
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• pp.341-349
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• 2021

연소시설에서는 화석연료에 포함된 질소와 황이 산소와 반응하여 대기 오염물질인 질소산화물(NO_X)과 황산화물(SO_X)을 발생시킨다. 인체에 유해하고 환경 오염을 야기하는 NO_X, SO_X를 저감하기 위해 전세계적으로 환경규제를 시행 중이며, 규제를 충족하기 위해 다양한 기술들을 적용하고 있다. 상용화된 NO_X 및 SO_X 저감방식들로 SCR (selective catalytic reduction), SNCR (selective non-catalytic reduction), WFGD (wet flue gas desulfurization) 등이 있으나 이 방식들의 단점들 때문에 NO_X, SO_X를 동시제거하는 연구가 근래 많이 수행되고 있다. 그러나 NO_X, SO_X 동시 제거 방식에서도 산화제 및 흡수제로 인한 폐수 발생에 대한 문제점, 특정 산화제를 활성화 하기 위한 촉매 및 전기분해 사용에 따른 비용 발생, 마지막으로 기체 산화제들 자체 유해성의 문제점을 가지고 있다. 따라서 본 연구에서는 NO_X, SO_X 동시처리 방식의 단점들을 보완하고자 고압분산기에서 생성된 마이크로버블과 환원제를 이용하여 비용절감 및 폐수처리 시 환경부하저감 가능성을 확인해 하고자 하였다. 분산기가 마이크로버블을 생성하는 것을 이미지 프로세싱과 ESR (electron spin resonance) 분석을 통해 확인하였으며, 마이크로버블만을 이용하여 온도에 따른 NO_X, SO_X 제거율 성능 테스트도 진행하였다. 뿐만 아니라 폐수를 저감하기 위해 환원제와 마이크로버블을 이용하여 습식으로 NO_X 제거율 약 75%, SO_X 제거율 99%를 달성하였다. 본 마이크로버블 시스템에 산화제를 함께 투여할 경우 NO_X, SO_X제거율 모두 99%이상을 달성 하였다. 이러한 연구 결과를 토대로 습식산화제거방식을 적용하는 시설의 단점이었던 비용 및 환경 문제를 해결함에 기여할 수 있을 것으로 기대 된다.

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

• Imaging Science in Dentistry
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• 제45권1호
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• pp.1-5
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• 2015

Purpose: Lateral pterygoid muscle (LPM) plays an important role in jaw movement and has been implicated in Temporomandibular disorders (TMDs). Migraine has been described as a common symptom in patients with TMDs and may be related to muscle hyperactivity. This study aimed to compare LPM volume in individuals with and without migraine, using segmentation of the LPM in magnetic resonance (MR) imaging of the TMJ. Materials and Methods: Twenty patients with migraine and 20 volunteers without migraine underwent a clinical examination of the TMJ, according to the Research Diagnostic Criteria for TMDs. MR imaging was performed and the LPM was segmented using the ITK-SNAP 1.4.1 software, which calculates the volume of each segmented structure in voxels per cubic millimeter. The chi-squared test and the Fisher's exact test were used to relate the TMD variables obtained from the MR images and clinical examinations to the presence of migraine. Logistic binary regression was used to determine the importance of each factor for predicting the presence of a migraine headache. Results: Patients with TMDs and migraine tended to have hypertrophy of the LPM (58.7%). In addition, abnormal mandibular movements (61.2%) and disc displacement (70.0%) were found to be the most common signs in patients with TMDs and migraine. Conclusion: In patients with TMDs and simultaneous migraine, the LPM tends to be hypertrophic. LPM segmentation on MR imaging may be an alternative method to study this muscle in such patients because the hypertrophic LPM is not always palpable.