• 제목/요약/키워드: Lobes

검색결과 572건 처리시간 0.03초

Design of Planar Microwave Bandstop Filters by Control of Wave Propagation on Nonuniform Transmission Line

  • Park, Eui-Joon
    • Journal of Electrical Engineering and information Science
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    • 제2권5호
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    • pp.114-120
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    • 1997
  • A design method is newly presented for the creation of planar type filters which shapes will be nonuniform transmission line with continuously varying characteristic impedances. Those filters yield frequency characteristics of the bandstop filter in transmission, and have not nay discontinuities. The design is achieved by the control of wave propagation in view to both reflection an transmission properties on the dispersive nonuniform line within the desired frequency band. The developed algorithm is based on optimized perturbations of inherent nulls of lobes from the solution of first-order nonlinear differential equation for reflection coefficients of the nonuniform line, and an appropriate distribution of reflection coefficient which affects to filter length and bandwidth. Practical measurements for designed wideband microstrip and stop filter show very good agreement with theoretical results.

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Physics of the Earth's plasma sheet associated with substorm triggering

  • 이대영
    • 천문학회보
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    • 제36권1호
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    • pp.33.1-33.1
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    • 2011
  • The plasma sheet of the Earth's magnetosphere is a sheet of hot plasmas in the magnetotail region, dividing the two (northern and southern) lobes of the Earth's magnetic field. It is the key region that is often closely linked to various electromagnetic dynamics in the Earth's magnetosphere-ionosphere system. In particular, it is the region that is most crucial for substorms, which is one of the most dynamic phenomena in the Earth's magnetosphere. The question of substorm triggering remains highly controversial until today, and at the center of the controversy there are several critical physics issues of the plasma sheet. In this talk I will introduce some of the physics issues of the plasma sheet. The specific topics that this talk will cover are (i) the general properties of the plasma sheet, (ii) fast plasma jets and plasma transport problem, (iii) stability/instability problem, and (iv) effects of thin current sheet. I will also present some of our group's recent findings regarding these topics, as obtained by comprehensive analyses of various observational data. The level and content of this talk are designed to be comprehensible to not only space physicists but also the scientists in a related field such as solar and heliospheric physics.

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A Circularly Polarized Waveguide Narrow-wall Slot Array using a Single Layer Polarization Converter

  • Kim, Dong-Chul;Min, Kyeong-Sik
    • 한국정보통신학회논문지
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    • 제4권1호
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    • pp.59-65
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    • 2000
  • This paper describes the characteristics of a one dimensional narrow-wall slotted waveguide array with a single-layer linear-to-circular polarization converter consisting of a dipole array. An external boundary value Problem of one slot and three dipoles, which approximates the mutual coupling between the dipole array and an edge slot extending over three faces of a rectangular waveguide, is formulated and analyzed by the method of moments; design of polarization conversion is conducted for this model as a unit element. If every unit element has perfect circular polarization, grating lobes appear in the array pattern due to the alternating slot angle: these are suppressed in this paper by changing the dipole angle and degrading the axial ratio of the unit element. The validity of the design is confirmed by the measurements. The dipole array has negligible effects upon slot impedance; the polarization conversion for existing narrow-wall slotted arrays is realized by add-on dipole array.

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광범위한 대뇌병터를 보인 대뇌형 부신척수신경병증 1예 (A Case of Cerebral Adrenomyeloneuropathy with Extensive Cerebral Lesions)

  • 김현정;민주홍;이광우
    • Annals of Clinical Neurophysiology
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    • 제9권2호
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    • pp.97-101
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    • 2007
  • We report a 31-year-old man with cerebral adrenomyeloneuronopathy variant, who presented as progressive gait disturbance. He had spastic paraparesis, hyperreflexia without Babinski's sign and sensory symptom. No adrenal insufficiency was noted. Brain MRI showed extensive high signal intensities in bilateral temporal lobes and posterior periventricular white matter in T2 weighed imaging without cerebrospinal fluid abnormality. His nerve conduction study showed sensorimotor demyelinating polyneuropathy and the level of saturated very-long-chain fatty acids was high in his plasma, although neuropsychological test was normal.

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A new record of the subgenus Eusimulium Roubaud from Korea with an updated key to genera and subgenera of Korean black flies(Diptera: Simuliidae)

  • Kim, Sam-Kyu
    • Journal of Species Research
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    • 제9권2호
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    • pp.174-179
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    • 2020
  • Larvae and pupae of Simulium (Eusimulium) satsumense were collected and recorded from Korea for the first time. Detailed descriptions and photographs of both immatures are provided. Currently, 42 species are known from the subgenus Eusimulium, which is found globally, mainly in the Holarctic Region, but unknown from Korea. Members of the subgenus Eusimulium are morphologically homogeneous in male, female, and pupa, making them extremely difficult to distinguish from one another. S. (E.) satsumense can be distinguished from other Korean black flies by the following combination of the characteristics: Pupa: Gill of four slender filaments, dorsalmost filament strongly divergent from other filaments; cocoon slipper shaped without anterodorsal projection; Larva: Head spots distinctly positive; postgenal cleft short, apically rounded or squared; antenna with proximal segment brown; abdominal segments IX with prominent ventral tubercles; and rectal papillae of three simple lobes. In addition to descriptions for larvae and pupae of the species, a key to genera and subgenera of Simulium of Korean black flies are also provided.

폐암환자에서의 기관지성형술을 이용한 폐엽절제술 (Sleeve Lobectomy for Bronchogenic Carcinoma)

  • 전상훈
    • Journal of Chest Surgery
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    • 제22권5호
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    • pp.794-799
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    • 1989
  • Sleeve lobectomy for bronchogenic carcinoma is an alternative to pneumonectomy. The extent and location of the tumor must be such that a sleeve procedure is feasible. The conservation of lung tissue benefits both compromised and uncompromised patients. From August 1988 to March 1989, five patients underwent sleeve lobectomy for bronchogenic carcinoma of the lung. The patients included four males and one female ranging in age from 52 years to 66 years. All patients were diagnosed as having squamous cell carcinoma. Operative procedures were right upper sleeve lobectomy in four cases and left upper sleeve lobectomy with pulmonary angioplasty in one case. Complications developed in one patient. An asthmatic attack necessitated ventilator support for one day. Bronchoscopic examinations were performed at two weeks and three months postoperatively in four patients. Anastomosis sites on all patients were intact, but in one case, nodules were noted. Pulmonary function tests were also checked at three months postoperatively, and showed good results. The reimplanted lobe or lobes contribute significantly to the overall remaining lung function. All patients are being followed up with satisfactory results, except one case of suspected local tumor recurrence. We think, therefore, that sleeve lobectomy is a safe and adequate procedure for patients with resectable lung cancer.

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Primary Synovial Sarcoma of Lung

  • Cabuk, Devrim;Ustuner, Berna;Akgul, Asli Gul;Acikgoz, Ozgur;Yaprak, Busra;Uygun, Kazim;Topcu, Salih;Muezzinoglu, Bahar
    • Journal of Chest Surgery
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    • 제47권3호
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    • pp.306-309
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    • 2014
  • Synovial sarcoma (SS) is a highly malignant tumor that accounts for 10% of all soft-tissue sarcomas. Primary SS arising from the lung is extremely rare, and the prognosis is poor. We report a case of pulmonary SS presenting with a mass lesion invading the right upper and middle lobes, extending to the mediastinum and the chest wall. After tru-cut biopsy, surgical resection was performed. The final diagnosis was SS (biphasic type) based on histological and immunohistochemical findings. There are no guidelines for optimal treatment due to the rarity of these tumors. Current treatment includes surgery and adjuvant chemotherapy and/or radiotherapy.

한국산 응애과 (거미속 : 진드기목) 의 분류학적 연구 (Taxonomic Study on Spider Mites (Tetranychidae ; Acarina ) of Korea)

  • 이원구;이병훈;김영진
    • Animal Systematics, Evolution and Diversity
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    • 제2권2호
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    • pp.13-26
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    • 1986
  • 다음과 같은 7종 응애과 (Family Tetranychidae ) 응애에 대하여 형태학적 특징, 표피의 주름, 핵형들을 비교함으로써 분류학적 검토를 실시하였다. 본 연구에 사용된 재료는 1985년 10월부터 1986년 6월 사이에 전북 전주에서 채집되고 사육된 것들이었다. Subfamily Bryobiinae 클러버등에 아과 :Bryobia praetiosa 클로버응애, Petrobia lantens 밀응애(신칭): Subfamily Tetranychinae 응애 아과, Panonychus citri 귤응애, P. ulmi 사과응애, Tetranychus vienensis 나무응애, T. urticae 점박이 응애. T.kanzawai 차응애(신칭), 그 중 밀응애와 차응애는 한국 미기록종이다.미기록종이다.

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New Records of Two Zooxanthellate Scleractinian Corals (Anthozoa: Hexacorallia: Scleractinia) from Korea

  • Choi, Eunae;Song, Jun-Im
    • Animal Systematics, Evolution and Diversity
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    • 제31권2호
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    • pp.86-94
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    • 2015
  • The two zooxanthellate scleractinian corals are newly recorded in Korea: Psammocora albopicta Benzoni, 2006 of the family Psammocoridae and Oulastrea crispata (Lamarck, 1816) of the family Faviidae. These families are also newly recorded in Korea. Specimens were collected from the subtidal zones of Jeju-do Island, Korea by SCUBA diving from 1999 to 2014. Two scleractinians are described based on the morphological characters of skeletal structures. Psammocora albopicta is distinguished by its encrusting cerioid growth form, high density of corallites, small calicular diameter, single styliform columella, and fewer rows of enclosed septa. Oulastrea crispata is characterized by its encrusting plocoid growth form, polygonal calicular shape, irregular paliform lobes, and papillose columella.

돈(豚)의 간회충증(肝蛔蟲症)에 관(關)한 병리학적(病理學的) 검색(檢索) (Pathological Changes in Hepatic Ascariasis of Swine)

  • 김상균;임창형
    • 대한수의학회지
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    • 제10권1호
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    • pp.33-38
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    • 1970
  • 1. Hepatic ascariasis represented by milk spots on the liver surface was found in 475(31.7%) out of 1,500 pigs. 2. For histopathological studies, 170 cases were collected at random from the milk spotted liver From these cases ascaris larva was found in 14 cases(8.2%). 3. Grossly, the occurrence of milk spots was not confined to any particular lobes of the liver. The lesions, however, were more frequently found in the diaphragmatic surface than in the visceral surface. The extent of the spots was limited to the subcapsular region and the deeper tissue was not affected. 4. Histologically, hemorrhage and eosinophilic infiltration were observed in the area invaded by the larva. The increase of connective tissue followed by a form of chronic lymphocytic hepatitis was observed at the late stage of infection. There was numerous eosinophilic infiltration around the larva trapped in the liver tissue. Consequently, encapsulation of the larva was followed by organization and calcification.

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