• 제목/요약/키워드: Feeding Point

검색결과 242건 처리시간 0.027초

WiBro 중계기용 Bazooka 발룬이 내장된 H형 슬롯 안테나의 설계 및 제작 (Design and Fabrication of the H-Type Slot Antenna with Bazooka Balun for a WiBro Repeater)

  • 최원준;김채영
    • 한국전자파학회논문지
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    • 제19권5호
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    • pp.515-522
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    • 2008
  • 본 논문에서는 Bazooka 발룬이 내장된 WiBro 중계 기용 슬롯 안테나를 설계하고 제작하였다. 도입된 Bazooka 발룬으로 인하여서 반사 손실과 복사 패턴 특성이 개선되었다. 즉, 복사 패턴의 일그러짐이 개선되었고, 또한 중계기의 안정된 커버리지가 보장되었다. 또한, Bazooka 발룬의 끝을 나사 형태로 설계하여 안테나 몸체에 쉽게 결합될 수 있도록 하였다. 안테나의 크기를 줄이기 위해서 H형의 슬롯을 사용하였고, 급전 지점을 중심으로 구조적 대칭이 되도록 하므로서 전방향성의 복사 패턴이 얻어지도록 하였다. 모의 실험은 상용 툴인 CST사의 MWS(Microwave Studio)를 사용하였으며, 네트워크 분석기와 원거리장 측정 시스템을 갖춘 무반사실에서 안테나 특성을 측정하였다. 제작된 안테나의 측정 결과, 최대 이득은 5.75 dBi이고, 평균 이득은 -0.8 dBi 이상이었다. 반사 손실은 WiBro 전체 대역에 걸쳐서 -12.35 dB 이하의 양호한 특성을 보였다.

수정된 Inset 급전선과 단일 슬롯을 이용한 이중대역 마이크로스트립 안테나 (Dual Band Microstrip Antenna with Modified Inset Feeder and a Slot)

  • 이승엽
    • 한국전자파학회논문지
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    • 제27권9호
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    • pp.800-807
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    • 2016
  • 본 논문에서는 수정된 inset 급전 구조와 단일 슬롯이 장하된 이중대역 마이크로스트립 안테나에 대해 연구하였다. 수정된 inset 급전선은 x방향의 수직 inset 급전선과 전체 inset 급전선의 길이를 줄이기 위해 추가된 y방향의 수평 inset 급전선으로 구성된다. 임피던스 정합을 위한 급전선의 전체 길이는 수평 inset 급전선의 길이를 조절함으로써 구현된다. 낮은 공진 주파수와 높은 공진 주파수 간의 비율도 슬롯의 치수를 변화시킴으로써 쉽게 얻을 수 있었다. 또한, 슬롯의 길이와 위치가 안테나 대역폭, 입력 임피던스 등에 미치는 영향을 고찰하였다. 안테나를 제작하여 실험한 결과, 공진 주파수 간의 비율을 1.25에서 1.88까지 변하게 하였다. 그리고 높은 공진 주파수 방사 패턴인 $TM_{30}$은 낮은 공진 주파수 방사패턴인 $TM_{10}$과 거의 같았으며, E평면에서 -20.0 dB 이하의 교차 편파 특성을 보였다. 이러한 결과들로써 본 연구에서 제안된 안테나는 단일 급전 이중 대역 안테나로서 이용될 수 있음을 확인하였다.

열간 스피닝 공정을 통한 CNG 고압용기의 돔 및 입구 부 성형 (Forming of Dome and Inlet Parts of a High Pressure CNG Vessel by the Hot Spinning Process)

  • 이광오;박건영;곽효서;김철
    • 대한기계학회논문집A
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    • 제40권10호
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    • pp.887-894
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    • 2016
  • 압축천연가스(CNG) 압력용기는 D.D.I공정을 통해 실린더부를 제작한 후, 스피닝 공정을 통해 돔 부 성형이 이루어진다. 그러나 스피닝 공정의 입구 부 성형에 관한 연구는 미미하며, 현장 작업자들의 경험이나 시행착오에 의해 제작되고 있는 실정이다. 이에 본 연구에서는 이론 임계좌굴하중 및 유한요소해석에서 축 방향 하중의 비교를 통하여 좌굴발생을 예측하였고, 상용 소프트웨어를 이용하여 돔부의 좌굴 방지를 위한 방법을 제안하였다. 또한, 입구 부 성형을 위하여 돔 부와 롤러가 맞닿는 점에서의 돔부의 반경에 따른 롤러 하중을 분석하고, 이를 토대로 입구 부 성형을 수행하였다.

NANDA간호진단과 간호중재분류(NIC)의 연계에 관한 타당성 연구 (A Validity Study for Linkage of Nursing diagnosis and Nursing Interventions Classification)

  • 박성애;박정호;정면숙;주미경;김복자;이은숙;박성희;유미
    • 간호행정학회지
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    • 제7권2호
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    • pp.315-347
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    • 2001
  • The purpose of this study was to validate the linkage of nursing diagnosis(NANDA) and Nursing Interventions Classification(NIC) for implementing the Nursing Diagnosis and Nursing interventions in Korea. 36 nurse experts with over the bacculate degree and over 15 years experiences working in tertiary hospitals participated in this study. 5 point Likert scales on each NIC linked 136 NANDA diagnoses were adopted. The results were as follows: 1. In a validity of linkage of nursing diagnosis and nursing interventions classification, the highest score is in 'Chronic low self esteem'(4.66), the lowest score is in 'sensory/Perceptual alterations; Auditory'(3.34) and the average validity score of the total items is 4.27. 2. There was significant differences by educational level and experience in validity score. 3. The nurses who have master degree have higher score than bachelor degree in the diagnoses; 'fatigue', 'health seeking behaviors', 'nutrition: potential for more than body requirements, altered', 'powerlessness'. 4. The nurses with experience over 20 years have higher validity score than less 15 years in 'breast-feeding, effective'. In conclusion, this research indicates that the linkage of NANDA diagnoses and NIC with high validity score can be applied to nursing practice in Korea. And further studies of nursing intervention are needed in Korean culture.

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어머니의 신생아에 대한 지각사정에 관한 연구 (A Study on Assessment of Mothers Perception of a Newborn Baby)

  • 이자형
    • 대한간호학회지
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    • 제16권3호
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    • pp.67-77
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    • 1986
  • The research was carried out in order to assess, at an early stage, the potential barrier in mother-child relationship in the childs' development by using the screening tool. Consequently, after modifying the Neonatal Perception Inventory developed by Broussard and testing its reliability. It has been applied to 152 mothers at the hospital of three universities in Seoul from August 1 to September 30, 1986. The data was analyzed by S.P.S.S. pro-gram and the results were as follows: 1) Mothers perceived the newborn as an individual, and evaluated their baby higher than other babies. 2) Mothers indicated difficulties in their role performance in the fellowing order-bathing, safety, detecting pain or suffering, and feeding. 3) Mothers' perception of a newborn was positive for 75% of the mothers. 4) The factor analysis of the modified tool using principal components analysis and Varimax rotation resulted in the two factors: Factor 1, Baby as an individual: Factor Ⅱ, Performances are required to meet the new-born's needs. 5) The difference in mothers' individual characteristics such as the number of childbirth, the desire to get pregnant or not, the type of deli-very, and the sex of the newborn did not influence on a mothers' perception of her newborn. As seen above, most of the mothers perceived their newborns as able individuals and expressed difficulties involved in taking care of the newborn. Also most of the mothers perceived their babies positively. My point here is, we ought to observe those mothers who perceive their babies negatively, and then compare them with those mothers who perceive their babies extremely positive or extremely negative. In the future, for more comprehensive assessment tool for maternal perception of the newborn, a repetitive verification and modification of this tool is demanded. At the same time, father's perception of the newborn should be included.

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가변곡률을 가진 나선형 블레이드 제작을 위한 원추형 롤 성형 공정설계 (Process Design of Conical Roll-Shaping for Fabrication of Variable Curvature Spiral Blade)

  • 양성문;심도식;지호성;백준호;김봉식;안석영;박상후
    • 한국정밀공학회지
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    • 제33권11호
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    • pp.911-918
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    • 2016
  • A conical roll-shaping process was proposed for fabrication of a metallic spiral blade applied to a small-scale wind turbine system. A spiral blade has continuously different curvatures, with a range of 100 to 350 mm radius. To fabricate this complex shape, we developed a conical roll-shaping process having two main conical rollers for feeding a blank sheet, and two cylindrical side rollers for control of local bending. For clear understanding of the process parameters, numerical analyses were conducted using a commercial code, Pam-Stamp. This study optimized the effects of process parameters, such as gap and angle between the main rollers and side rollers, and also the movement of side rollers. In order to increase the forming efficiency, a central rotation point was also calculated by the analytical approach. This developed rolling process can thus be utilized in a sheet metal forming process for obtaining spirally curved sheet metal shapes.

유리피판을 이용한 설재건 후의 기능평가 (Functional Assessment after Tongue Reconstruction using Free Flap)

  • 박성호;정철훈;이종욱;장용준;노영수
    • 대한두경부종양학회지
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    • 제25권2호
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    • pp.119-122
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    • 2009
  • Objectives : Ablation of carcinoma of the tongue leads to deficits in speech and swallowing, but none to date has provided all of the qualities of mobility and sensation to simulate the complex function of the tongue. The authors evaluated postoperative swallowing and pronouncing function in patients who underwent tongue reconstruction using free flap. Material and Methods : This is a retrospective review documenting the outcome of 42 patients between January of 1991 and August of 2008. We classified patients according to the size of resection of the tongue like as 7 partial glossectomy, 25 hemiglossectomy, 2 subtotal glossectomy, and 8 total glossectomy. Swallowing function was graded into 4 point scale and pronouncing function was analyzed using picture consonant articulation test. Aspiration was evaluated with videofluoroscopic swallowing study. Results : The average points for swallowing function were 3.43 in partial glossectomy, 3.52 in hemiglossectomy, 3 in subtotal glossectomy, and 2.63 in total glossectomy. The percentage of consonants correct showed 76.5% in partial glossectomy, 72.29% in hemiglossectomy, 47.69% in subtotal glossectomy, and 29.94% in total glossectomy. Aspiration was noted in 3 patients(1 hemiglossectomy and 2 total glossectomy) and 2 total glossectomy patients were taken permanent feeding gastrostomy. Conclusion : Free flap gave us proper volume in tongue reconstruction and showed good result in preserving swallowing function. Swallowing function difference according to the size of defect showed no statistical significance, whereas articulation function was shown to decrease in accuracy as the size of defect was larger.

조사료 생산을 위한 농업기계의 적정모형 설정 (Establishment of Optimum Pattern of Farm Machinery for Forage Production)

  • 김건엽;김정갑;한민수
    • 한국초지조사료학회지
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    • 제15권3호
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    • pp.222-230
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    • 1995
  • This study was canied out to ddermine optimum areas for various sizes of land coverage of the farm machinery utilization in 1993-1994. A kind of machinery size and work systems were classed as the power tiller of 10HP+man power, the tractor of 35~46HP (tractor of 64~86HP and attachment were leased to harvest work), 64-86HP+ attachment and 90- 105HP+ attachment, respectively. \ulcornerhe results are summarized as follows: 1. The optimum areas of tractors of 90~105HP, 64~86HP and the power tiller of lOHP were estimated as 21.9 (corn-rye cropping system)- 26.9ha (sorghum $\times$ sudangrass - rye cropping system), 14.7 - 22.8ha and 1.2 - 1.61ha, respectively. The break-even-point areas of the tractors of 90-105HP. 64-86HP and the power tiller of lOHP were 16.6 (corn-rye cropping system)- 19.9ha (sorghum $\times$ sudangrass - rye cropping system), 12.5 - 16.lha and 0.12-0.13ha, respectively. 2. The optimum areas (land sizes, annual field capacity) for 50 cows by feeding rate(%) of roughage to concentrate were 6.8ha, 13.6ha in the 4060, 8.5ha, 17.0ha in the 5050 and 10.2ha, 20.4ha in the 60:40, and in case of 30 cows, it were 4.lha, 8.2ha in the 40:60, respectively. In the former case for the form of work system was the trador of 90-105HP+attachment and 64~86HP+ attachment, and the latter was the tractor of 35~46HP (tractor of 64~86HP and attachment were leased to harvest work) and 64-86HP+ attachment. 3. Productiori cost for corn-rye cropping system reducted to 51.8% in 102.9 wonkg dry matter the tractor of 90~ 105HP+ attachment with 213.4 wonkg dry matter the power tiller of 10HP+ man power.

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적외선 센서를 이용한 돼지 체온 모니터링 (Monitoring of Pig Body Temperature Using Infrared Sensors)

  • 장진철;이준엽;이상윤;김혁주;최동윤;이성현;김현태
    • 한국축산시설환경학회지
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    • 제20권3호
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    • pp.91-96
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    • 2014
  • The temperature of a pig is the most key point in determining, it's health status. We wanted to monitor the body temperature of pig to find out if any changes would occur, we used 3 minipigs (about 20 kg) who were feed using a feeding system while being confined in a pig house. The infrared testings were taken from a height of 30 cm above the pigs backs over a period of 28 days. We were able to conclude that the results between the back and indoor temperature were y = 0.5487x + 18.459. These values were compared with the values found after infrared sensor results were taken. We found an error range of $0.004{\sim}1.82^{\circ}C$ and an average of $0.58^{\circ}C$. In conclusion, using an infrared thermometer made monitoring of pigs back possible. This system seems to be feasible and effective in monitoring pig temperature.

이동통신 광대역 PIFA 안테나 설계 및 해석 (The Design of Broadband PIFA for Hand-Held Mobile Phones)

  • 김상준;이대헌;박천석
    • 한국전자파학회논문지
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    • 제14권8호
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    • pp.855-862
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    • 2003
  • 본 논문에서 제안하는 안테나는 기존 내장형 안테나의 일종인 PIFA의 단점으로 협대역 문제를 해결하기 위하여, 복사 소자와 접지면 사이에 단락판을 위치시키는 변형된 안테나 형태인 PIFA(Planar Inverted-FAntenna) 구조를 제안하였다. 또한 보다 넓은 대역폭을 가지도록 방사 패치에 톱니모양의 perturbation을 주었다. 제안된 방식으로 단말기에 내장형으로 사용하기 위하여 안테나의 높이(h=0.015λ)를 최소한으로 하여 원하는 대역폭(5.2 %)을 얻었다. slim형으로 하기 위해 안테나의 특성을 급전위치(Yf, Zf), 단락 스트립(Short plate)의 위치 (Zs), 폭 (Ws), perturbation폭(w), 길이(d), 단락 스트립 높이(h), 유전율 변화($\varepsilon$$_{r}$)가 안테나에 어떤 변화를 미치는지를 조사하였다. 또한 기존 PIFA 안테나와의 대역을 비교하고, 제안된 패턴을 H, E plane으로 나타내었다. 논문의 객관성을 입증하기 위하여 FIM(Finite Integration Method) 방식에 기반인 MWS(Microwave Studio) 소프트웨어를 이용하여 Simulation 하였으며, 각각의 구조 파라미터 변화에 따른 안테나 특성을 분석하였다. 그리고 실제 제작한 안테나의 실험결과와 비교하여 증명한 결과, 제안된 방식의 PIFA 안테나 실용화가 가능성을 확인하였다..