• Title/Summary/Keyword: NEC

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Standardization Analysis of 'NEC Article 690' for Photovoltaic Shutdown Technology (태양광(PV) 셧다운(Shutdown)기술 'NEC Article 690' 표준화 분석)

  • Yoon, Yongho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.3
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    • pp.171-176
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    • 2022
  • The communication signal for quick cut-off specification is defined as "design to support fast cut-off requirements of all applicable photovoltaic(PV) systems" in NEC 2014, NEC 2017 or the corresponding UL standard regardless of the system configuration. On the other hand, if you look at the domestic regulations related to new and renewable energy, the standards, regulations, and guidelines set by each institution are general, or only the parts necessary for the institution are being established and operated. There are many insufficient points to apply these things to photovoltaic facilities, and there are cases where excessive facilities are installed according to the design, inspection standards of supervisors and inspection agencies, and the skill level of inspectors. The internationally accepted IEC standards deal with various facility standards in detail. In each European country, there are separate facility regulations based on IEC. In particular, the performance and safety of devices are dealt with in detail, and in the case of 'NEC Article 690' applied in North America such as the United States, each item is described in detail. Therefore, in this paper, we will look at the details of the PV shutdown technology that is currently used and applied internationally.

Three Cases of Neuroendocrine Carcinoma of the Larynx (후두에 발생한 신경 내분비암종 3예)

  • Yeo, Nam-Kyung;Choi, Seung-Ho;Kim, Sang-Yoon;Nam, Soon-Yuhl
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.16 no.1
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    • pp.76-80
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    • 2005
  • Although primary neuroendocrine carcinomas(NEC) are uncommon tumors of the larynx, they represent the most common nonepidermoid malignancy of this organ. Whereas typical carcinoid tumors and small-cell carcinomas occur very rarely in the larynx, the majority of laryngeal NEC belong to a broad intermediate group between these two extremes of NEC. Through many case studies, a major protion of clinicopathologic characteristics of laryngeal NEC have been revealed; however, the gistogenesis of laryngeal NEC is still unknown. The only well-documented normal neuroendocrine structures of the larynx are paraganglions, but the incidence of laryngeal paragangliomas are much lower than that of NEC. Here, we report on three cases of NEC affecting the larynx and the results of searching for neuroendocriene cells in non-neoplastic larynx tissue.

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Descending Aorta Blood Flow Characteristics before the Development of Necrotizing Enterocolitis in Preterm Neonates

  • Kim, Kyung Min;Kim, Hyo Sup;Yoon, Ji Hong;Lee, Eun-Jung;Yum, Sook Kyung;Moon, Cheong-Jun;Youn, Young-Ah;Kwun, Yoo Jin;Lee, Jae Young;Sung, In Kyung
    • Neonatal Medicine
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    • v.25 no.2
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    • pp.78-84
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    • 2018
  • Purpose: To investigate the hemodynamic risk factors for necrotizing enterocolitis (NEC), we analyzed the characteristics of descending aorta (DA) blood flow in preterm neonates, who later developed NEC. Methods: This was an observational case-control study on 53 preterm neonates at a tertiary referral center. Clinical and echocardiographic data were collected from 23 preterm neonates with NEC (NEC group), and compared with those of 30 preterm neonates without NEC (control group). Echocardiography was done at a median (interquartile range) of 5 (3-9) days after birth and 2 (1-2.5) days before the diagnosis of NEC. Results: Basic clinical characteristics including gestational age, birth weight, Apgar score, breast feeding status, use of umbilical catheters, and mode of invasive ventilator care were similar between the groups. Compared with the control group, the lowest diastolic velocity of DA was significantly decreased, whereas the diastolic reverse flow and the ratio of diastolic reverse to systolic forward flows were significantly increased in the NEC group. In addition, the resistive index (RI) of DA was significantly increased in the NEC group and showed a positive association with the development of NEC. Multivariate logistic regression analysis showed that increasing RI of DA was an independent risk factor for the development of NEC (P=0.008). Conclusion: Significant changes in DA flow characteristics including decreased diastolic velocity and increased diastolic reverse flow along with increased peripheral vascular resistance were observed before the development of NEC in preterm neonates. These findings may help clinicians stratify in advance neonates at a risk of developing NEC and may help improve outcomes in these neonates.

Tiled Ribbon-shaped Thin Silicon Grains Produced with Comb-shaped Beam in ZMR-ELA

  • Nakata, Mitsuru;Okumura, Hiroshi;Kanoh, Hiroshi;Hayama, Hiroshi
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.412-414
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    • 2004
  • We have developed nucleation control methods applicable to a zone-melting recrystallization excimer laser annealing process for poly-Si films. Ribbon-shaped Si grains of 2 ${\mu}m$-width were successfully aligned side by side by means of a comb-shaped beam, and we have successfully fabricated TFTs with channels formed in those grains. Electron mobility in the TFTs is as high as 677-$cm^2$/Vs.

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Quad-functional Built-in Test Circuit for DRAM-frame-memory Embedded SOG-LCD

  • Takatori, Kenichi;Haga, Hiroshi;Nonaka, Yoshihiro;Asada, Hideki
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.914-917
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    • 2008
  • A quad-functional built-in test circuit has been developed for DRAM-frame-memory embedded SOG-LCDs. The quad function consists of memory test, display test, serial transfer test, and parallel transfer test which is the normal operation mode for our SOG-LCD. Results of memory and display tests are shown.

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Application of OGC services to Digital Asia

  • Hiraishi, Kenji;Shibata, Norifumi;Nagano, Tetsuya
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1436-1438
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    • 2003
  • A prototype of OGC Web Map Service and Web Feature Service is developed by NEC Aerospace Systems, Ltd. under the contract from NASDA and RESTEC. The server provides satellite imagery data taken by JERS-1 and ADEOS satellite, via OGC interfaces to the client. The related features are also available to the client through the Internet with OGC interfaces. The imagery, map and feature data is handled layer by layer at the client. OGC Web Map Service and Web Feature Service interoperability capability and applicability to Digital Asia Network are demonstrated.

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Neonatal Rat Necrotizing Enterocolitis Model Adopting Oral Endotoxin and Hypoxia Exhibits Increased Apoptosis through Caspase-3 Activation (경구 내독소와 저산소로 유발된 신생쥐의 괴사성 장염모델에서 caspase-3 활성화를 통한 세포자멸사의 증가)

  • Lee, Yun-Kyoung;Kim, Ee-Kyung;Kim, Ji-Eun;Kim, Yoon-Joo;Son, Se-Hyung;Kim, Han-Suk;Kim, Beyong-Il;Choi, Jung-Hwan
    • Neonatal Medicine
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    • v.17 no.1
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    • pp.44-52
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    • 2010
  • Purpose : The aim of this study was to develop a model for necrotizing enterocolitis (NEC) in the neonatal rat using endotoxin and hypoxia, a plausible insult in a neonatal intensive care and to investigate the role of apoptosis as the underlying mechanism. Methods : Newborn rats were given oral endotoxin and intermittent 8% hypoxia$\pm$caspase inhibitor. The intestinal histology was evaluated using hematoxylin-eosin staining. Apoptosis was analyzed with TUNEL staining and by measuring the caspase 3 activity in the intestinal lysates. IEC-6 cells were assessed for apoptosis and the expression of Bax, Bcl-2, Fas and FasL was measured after treatment with endotoxin and hypoxia. Results : Oral endotoxin (5 mg/kg) and exposure to 8% hypoxia of 60-min duration twice induced human NEC-like lesions in the rat intestine. Intestinal tissue revealed increased apoptosis and caspase-3 activity. After caspase inhibitor treatment, the grades of both apoptosis and NEC were significantly reduced. IEC-6 cells exhibited increased apoptosis and caspase 3 activity after endotoxin and hypoxia treatment and significantly increased Bax/Bcl- 2 ratio compared to control cells. Conclusion : This neonatal rat model of NEC which was induced by oral endotoxin and intermittent hypoxia showed increased apoptosis of intestinal epithelial cells that was mediated by caspase 3 activation. Our model has a advantage in the study of NEC because the use of much more clinically plausible insults may provide a suitable model for the investigation of its pathophysiology and therapeutic trials.

A real Implemention of an Adaptive Self-tuning Filter Using an NEC 7720 DSP (NEC 7720 DSP를 이용한 적응자기 동조필터의 실시간 구현)

  • 이연석;이상욱;이장규
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.36 no.5
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    • pp.367-376
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    • 1987
  • In this paper we have disigned and implemented a real time ALE (adaptive line enhancer) using a high speed digital processor,NEC 7720. For the ALE system, we have employed an adaptive LMS(least mean square) algorithm proposed by Widrow and Hoff and a 32-order FIR(finite impulse response) filter. Extensive computer simulations have been performed to investigate the peformance of the ALE and to determine necessary parameters for hardware design. The developed software for an NEC 7720 was tested in real time operation using an NEC7720 hardware emulator. The ALE has been tested by sinusoidal waves and real CW (continuous wave) signals. It was found that the experimental results were well agreed with the computer simulation results. Thus it can be concluded that the ALE is useful for detection and enhancement of a sinusoidal signal which is corrupted by an additive Gaussian noise.

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Fecal calprotectin concentration in neonatal necrotizing enterocolitis

  • Yoon, Jung Min;Park, Ju Yi;Ko, Kyung Ok;Lim, Jae Woo;Cheon, Eun Jeong;Kim, Hyo Jeong
    • Clinical and Experimental Pediatrics
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    • v.57 no.8
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    • pp.351-356
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    • 2014
  • Purpose: Among the many factors associated with acute intestinal mucosal infection, numerous studies have proposed the usefulness of fecal calprotectin. The aim of this study was to evaluate the usefulness of fecal calprotectin in the diagnosis of necrotizing enterocolitis (NEC). Methods: We collected 154 stool samples from 16 very low birth weight and premature newborns at the Konyang University Hospital neonatal intensive care unit or neonatal nursery. The stool samples were collected using the Calprest device, and the fecal calprotectin level was measured with the $B\ddot{U}HLMANN$ Calprotectin enzyme-linked immunosorbent assay kit. Results: Fecal calprotectin levels were significantly higher in the NEC group than in the non-NEC group (P=0.02). There was a significant positive linear relationship between the fecal calprotectin level and number of days after birth (P=0.00) in the gestational age <26 weeks group. There was a significant negative linear relationship between the calprotectin level and number of days after birth (P=0.03) in the gestational age ${\geq}26$ weeks and <30 weeks group. There was no difference in the calprotectin levels according to the type and method of feeding between the NEC and non-NEC groups. Conclusion: Fecal calprotectin levels were significantly increased in premature infants with NEC. The fecal calprotectin test is a noninvasive, easy, and useful tool for the diagnosis of NEC.