• Title/Summary/Keyword: NSA

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A Study on Improvement of Method for Measuring the Shield Performance of Shielding Enclosures (전자파 차폐실의 차폐효과 측정방법 개선에 관한 연구)

  • Yeon, Jae-Sung;Kim, Hie-Sik
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.350-353
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    • 2009
  • The shielding enclosure is very essential device to test the electromagnetic wave power generated by various RF equipments. Some standards for the shielding enclosures were established to test them in right method. Generally, There are IEEE-STD-299 and MIL-STD-285 and NSA-65-6 of the method for measuring the effectiveness of shielding enclosures, the IEEE-STD-299 combined MIL-STD-285 and NSA-65-6 about the method for measuring shielding effectiveness(SE) about 1969 years, but, the measurement point of 299 proposal is many points(including shielding wall, seam, coner beat, shielding door, etc) and demand long time of measurement. To improve SE test method for shielding enclosures was studied and suggested to develop a proper test procedure. First, we measure reference level as frequency range and H/V polarization, secondly, measure leakage point, and finally, measure shield effect and calculate SE. Our method has a merit of the less measurement point than IEEE-STD-299, and shorten time than 299, and define representation SE of shielding enclosure effectively.

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테마연재 / 에셜론[Echelon]에 의한 도·감청 및 프라이버시 침해..

  • Kim, Yeon-Su
    • Digital Contents
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    • no.10 s.101
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    • pp.76-83
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    • 2001
  • 미국 NSA는 미 국방부 산하 비밀정보기관으로 그중 하나인 국방정보국(DIA)와 함께 미국의 (대외)전자정보 첩보활동 기능을 하고 있다.워싱턴과 볼티모어 중간의 메릴랜드주 포트 미드에 본부를 두고 있으며 3만 8천명의 인원과 1년 예산 41조원으로 운영되고, 6000평의 지하에 설치된 수퍼컴퓨터들을 작동하고 있는 것으로 알려졌다.FBI나 CIA와는 별개의 조직이며 미 육군 안전국 및 해군과 공국의 통신정보기구에 대해서도 광범위한 감독권을 갖는다. 에셜론에 대한 관리 및 그 존재에 대한 의구심은 에셜론이 네트워크를 통하여 자국민은 물론 다른 나라의 국가 기업 기밀을 포착하고 있으리라는 추측을 불러 일으키고 있음에도 불구하고 미국과 영국은 에셜론의 실체 및 에셜론을 통한 정보탐지 여부를 철저하게 부인해 왔으나 호주 및 뉴질랜드 정부가 이사실을 인정하기 시작하였고 영국 BBC방송사는 1999년 11월 2일 오스트레일리아 정보보안부 감찰관 빌 블릭이 NSA를 중심으로 하는 세계적인 통신감청망 에셜론이 존재하며 자신이 일했던 호주 방위통신대도 이 감청망의 일부라고 확인했다고 보도했다.

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Physiological Activities of Ginger Extracts Originated from Different Habitat

  • Lim, Tae-Soo;Oh, Hyun-In;Kwon, Joong-Ho;Kim, Hyun-Ku
    • Food Science and Biotechnology
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    • v.15 no.1
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    • pp.143-147
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    • 2006
  • Physiological activities of Korean-grown ginger (KG) and Chinese-grown ginger (CG) extracts were examined. Ginger was extracted with water, and 50 and 100% ethanol, and then nitrite-scavenging activity (NSA), superoxide dismutase (SOD)-like activity, and electron-donating ability (EDA) of extracts were investigated. NSA at pH 1.2 was the most effective in 50% ethanol extracts of both origins. SOD-like activities of water and 50% ethanol extracts of both samples were 8.66-35.95% lower than those of 1 and 0.1% L-ascorbate solutions. SOD-like activity of KG extracts was higher than that of CG extracts, and water extracts of samples were the highest. EDA of KG extract was higher (22.23-86.95%) than that of CG extract, while both sample extracts showed lower EDA than those of 1 and 0.1% L-ascorbate solutions.

A Study on the Performance Verification Method of an ALSE(Absorber-Lined Shielded Enclosure) by the CISPR25 (CISPR25의 ALSE(Absorber-Lined Shielded Enclosure) 성능 검증 방법에 관한 연구)

  • Shin, Jaekon;Jung, Kibum;Choi, Jaehoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.8
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    • pp.791-797
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    • 2013
  • This paper proposes a new way to verify the performance of an absorber lined shielded enclosure(ALSE) in accordance with CISPR25, EMC standards dedicated to testing automotive components. CISPR16 requires the use of NSA and VSWR methods to test the performance of a chamber. As for CISPR25, however, there hasn't been standardized ways to verify the performance of ALSE. This paper purports to present an improved method for the verification based on a long-wire antenna method under discussion at CISPR25 JFT. Existing discussions on a long-wire antenna method proposes that an antenna should reach 500 millimeters in length, while this paper adopts the antenna length of 1,700 millimeters. This paper also assesses the effects of matching conditions and studies problems related to methods which have been already proposed and key parameters in order to improve verification methods.

Minimally Invasive Percutaneous Plate Osteosynthesis via a Deltoid-splitting Approach with Strut Allograft for the Treatment of Displaced 3- or 4-part Proximal Humeral Fractures

  • Noh, Young-Min;Kim, Dong Ryul;Kim, Chul-Hong;Lee, Seung Yup
    • Clinics in Shoulder and Elbow
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    • v.21 no.4
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    • pp.220-226
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    • 2018
  • Background: This study introduces a surgical technique with good clinical outcome useful in the treatment of osteoporotic displaced 3- or 4-part proximal humeral fractures. Methods: From May 2014 to February 2016, 16 patients with displaced 3- or 4-part proximal humeral fractures were treated by application of a locking plate with an endosteal strut allograft via a deltoid splitting approach with a minimum follow-up of 12 months. The allograft was inserted through a fractured gap of the greater tuberosity to support the humeral head and then fixed by a locking plate with meticulous soft tissue dissection to protect the axillary nerve. Surgical outcomes were evaluated by the American Shoulder and Elbow Surgeons (ASES) and visual analogue scale (VAS) scores, radiological imaging, and clinical examination. Fixation failure on radiographs was defined as a >$5^{\circ}$ loss of neck shaft angle (NSA) compared to that on an immediate postoperative radiograph. Avascular necrosis (AVN) of the humeral head was also evaluated. Results: In all cases, complete union was achieved. The ASES and VAS scores were improved to $85.4{\pm}2.1$ and $3.2{\pm}1.3$, respectively. Twelve patients (75.0%) had greater than a $5^{\circ}$ change in NSA; the average NSA change was $3.8^{\circ}$. Five patients (31.3%) had unsatisfactory ranges of motion exhibiting a <$100^{\circ}$ active forward flexion. No axillary nerve injuries or AVN were observed at the last follow-up. One patient was converted to reverse total arthroplasty due to severe pain and functional deficit. Conclusions: Minimally invasive fixation via a locking compression plate and an endosteal fibula strut allograft in Neer classification 3-or 4-part fractures with severe osteoporosis in elderly patients can achieve good clinical results.

Antioxidative activity of Extracts from Gardenia jasminoides and Quality Characteristics of Noodle Added Gardenia jasminoides Powder (치자 추출물의 항산화능과 치자 첨가 국수의 품질특성)

  • Kim Mi-Lim
    • Korean journal of food and cookery science
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    • v.22 no.2 s.92
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    • pp.237-243
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    • 2006
  • This study investigated the development of increased health promotion and higher quality of Gardenia jasminoides noodles. Gardenia jasminoides powder was extracted with water and 70% ethanol, after which their electron donating ability (EDA) and nitrite scavenging ability (NSA) were tested. EDA at $300{\sim}1,000$ ppm of water extract ranged from 65% to 86% and that of ethanol extract from 69% to 91%. NSA of water extract was 79% and ethanol extract was 88% at 1,000 ppm both peaked at pH 1.2. NSA was increased with increasing concentration of extracts and decreasing pH. The quality characteristics of Gardenia jasminoides noodles were evaluated by shelf life, color and sensory evaluation. Total viable cells in Gardenia jasminoides noodles during storage at 5? were $0.2{\sim}0.3$ log cycles, which were lower than those of the control and the shelf-life was expanded. Redness (a) of the dried and cooked noodles was decreased with increasing Gardenia jasminoides concentration (p<0.05). Yellowness (b) of the noodles was increased with increasing Gardenia jasminoides concentration in both the dried and cooked noodles. In sensory evaluation, dried and cooked noodles with $0.2{\sim}0.3%$ Gardenia jasminoides powder d significantly higher scores in overall acceptability(p<0.05).

Sensory Characteristics of Korean Wheat Noodles With Pine pollen and Antioxidant activities of Pine pollen Extracts (송화를 첨가한 우리밀 국수의 관능특성 및 송화추출물의 항산화성)

  • Kim, Mi-Lim
    • Korean journal of food and cookery science
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    • v.21 no.5
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    • pp.717-724
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    • 2005
  • Sensory characteristics and antimicrobial activity of Korean wheat noodle with pine pollen powder and antioxidant activity of pine pollen extracts were investigated to develop the health promoting product. Pine pollen powder was extracted with water and 70% ethanol and extracts were tested electron donating ability (EDA) and nitrite scavenging ability (NSA). Sensory characteristics were evaluated by its color, flavor, moisture, softness, texture and taste. Microbiological quality was tested by total viable cells. EDA was highest in 1,000 ppm for both water extract (67% of EDA) and ethanol extract (74% of EDA). NSA was highest in pH 1.2 for both water extract(46% of NSA) and ethanol extract (48% of NSA). Antimicrobial activity of Korean wheat noodle with 3% pine pollen powder were 0.5 log $cycle{\sim}1$ log cycle lower than that of control at 5days of storage in total vival cells and at 4days of storage in total fungus. From sensory evaluation, Korean wheat noodle with 3% pine pollen powder had significantly higher of all scores.

Antioxidative and Nitrite Scavenging Activities of Polygonatum odoratum Root Extracts with Different Steaming and Roasting Conditions (둥굴레 근경의 증자 및 볶음조건에 따른 추출물의 항산화성 및 아질산염 소거능 변화)

  • Kim Kyung-Tae;Kim Jung-Ok;Lee Gee-Dong;Kwon Joong-Ho
    • Food Science and Preservation
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    • v.12 no.2
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    • pp.166-172
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    • 2005
  • Response surface methodology (RSM) was applied to monitor the effects of steaming and roasting conditions of Polygonatum odoratum roots an total phenolics content, electron donating ability (EDA) and nitrite-scavenging ability (NSA) of the extract. In steaming and roasting processes based on the central composite design. with variations in steaming time $(60\~180\;min)$, roasting temperature $(110\~150\;min)$ and roasting time $(10\~50\;min)$, coefficients of determinations $(R^2)$ were 0.9356 (p<0.01) in total phenolics, 0.9578 (p<0.01) in EDA and 0.9436 (p<0.01) in NSA (pH 3.0). The maximum value of total phenolics was $2847.67\;mg\%$ at 135.59 min of steaming time, $143.84^{\circ}C$ of roasting temperature and 43.47 min of roasting time. The maximum value of EDA was $75.00\%$ in 108.98 min, $135.56^{\circ}C$ and 48.86 min. The maximum value of NSA (pH 3.0) was $87.38\%$ in 162.80 min, $143.88^{\circ}C$ and 31.97 min, respectively. Total phenolics content of the extract was influenced by heating conditions in the order of roasting temperature, steaming time and roasting time. While EDA and NSA were appreciably influenced by roasting time, followed by roasting temperature and steaming time.