• 제목/요약/키워드: $D_{50}$

검색결과 9,727건 처리시간 0.041초

Comparison of Predicted Acoustics with the Measured Acoustic Properties of a Multi-Purpose Hall

  • Haan, Chan-Hoon
    • The Journal of the Acoustical Society of Korea
    • /
    • 제25권3E호
    • /
    • pp.95-100
    • /
    • 2006
  • The present study presents the design procedures and the acoustic properties of the main hall of Ansan Cultural Arts Center in Korea which has opened in 2004. The acoustic design values are compared with the measured acoustic properties of the completed multi-purpose hall. Acoustic design criteria were suggested in the design stage through the 3-dimentional computer simulations. The acoustic parameters including SPL, RT, C80, $D_{50}$M, RASTI were measured in the hall after completed. Acoustic measurements were carried out in the 40 measurement points using MLS sound source signal in 4 different sound source points. The results show the even distribution of sound levels within the 2.0dB of difference among all seats. The reverberation time of 1.66sec was measured which is similar to the objective value of 1.65 sec in empty states. It was also found that average C80 values lie in the objective extents of C80 from -1 to 3dB and average D50 value of 54 was measured. Thus, it is concluded that the hall can be used as a multi-purpose hall with a suitable acoustic conditions.

UHF RFID 리더기용 원형편파 안테나 설계 (Design of a Circularly Polarized Antenna for UHF Band RFID Reader)

  • 천종훈;한승조;변재영;임경;박종안
    • 한국ITS학회 논문지
    • /
    • 제6권3호
    • /
    • pp.101-110
    • /
    • 2007
  • 본 논문에서는 UHF대역의 RFID 리더기용 원형편파 안테나를 설계 제작하였다. 그리고 설계 제작된 안테나의 성능분석을 통하여 Return Loss (S11)는 914 MHz에서 약 -45.529 dB로 상당히 적었으며, 안테나 이득은 약 6.09 dBi값을 얻었다. 또한 임피던스 매칭은 약 $50.48\;{\Omega}$이고, 사용 대역 중심 주파수인 911 MHz에서 축비는 1.2 dB로 설계되어 모든 RFID 리더기에 적용 가능함을 확인하였다. 따라서 RFID 리더기의 파라미터에서 가장 중요한 것 중 하나는 수신감도를 향상시켜서 원거리에서도 멀티태그를 인식하는데 있어서 원형편파 안테나의 이득을 높게 설계 제작함으로써 감도를 향상 시킬 것으로 기대 된다.

  • PDF

제주 50MVA STATCOM 설치 효과 분석 (Installation of 50MVA STATCOMs in Jeju Power System)

  • 한영성;정정주;박정수;여상민;송지영;서인영
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2010년도 하계학술대회 논문집
    • /
    • pp.328-329
    • /
    • 2010
  • STATCOM은 전력전자 기반의 전압형 인버터를 이용한 무효 전력 보상장치로써 우수한 전압 제어 능력과 빠른 동작 특성, 그리고 운용 및 유지/관리의 유연성으로 인해 기존에 사용되던 무효 전력 보상장치들을 빠르게 대체하고 있다. 효성중공업에서는 국내 최초로 100MVA STATCOM을 개발하여 한전 실 계통에 설치/운용한 바 있고 이 경험을 바탕으로 최근 논의되고 있는 제주 50MVA STATCOM의 개발에 착수하였다. 본 논문에서는 이 프로젝트와 관련된 배경을 설명하고 연구 과정 중에 수행된 제주 전력 계통의 STATCOM 설치 효과 모의 결과에 대해서 소개하고자 한다.

  • PDF

오목표면에 분사되는 난류원형충돌제트에 대한 국소열전달계수 측정에 관한 연구 (Measurement of the Local Heat Transfer Coefficient on a Concave Surface with a Turbulent round Impinging Jet)

  • 임경빈
    • 설비공학논문집
    • /
    • 제7권1호
    • /
    • pp.112-119
    • /
    • 1995
  • Measurements of the local heat transfer coeffcients on a spherically concave surface with a round impinging jet are presented. The liquid crystal transient method was used for these measurements. This method, which is a variation on the transient method, suddenly exposes a preheated wall to an impinging jet while video recording the response of liquid crystals for the measurement of the surface temperature. The Reynolds numbers used were 1,000, 23,000 and 50,000 and the nozzle-to-jet distance was L/d=2, 4, 6, 8, 10. Presented results are compared to previous measurements for flat plate. In the experiment, the local heat transfer Nusselt numbers on a concave surface are higher than those on a flat plate. Maximum Nusselt number at all region occured at L/d=6 and second maximum in the Nusselt number occured at R/d=2 for both Re=50,000 and Re=23,000 in case of L/d=2 and for only Re=50,000 in case of L/d=4. All other cases exhibit monotonically decreasing value of the Nusselt number along the curved surface.

  • PDF

쪽파(Allium wakegi Araki)의 아미노산 분석과 항산화 활성 (Amino Acid Analysis and Antioxidation Activity in Allium wakegi Araki)

  • 류상현;송원섭
    • 한국자원식물학회지
    • /
    • 제17권1호
    • /
    • pp.35-40
    • /
    • 2004
  • 쪽파의 잎과 인경, 2,4-D 0.5, 1.0mg/L가 첨가된 MS배지에서 배양된 캘러스로부터 아미노산 분석과 항산화활성 을 분석하였다. 총아미노산 분석의 함량은 자연조건상태의 잎에서는 59.779 mg% 함유하였으나 2,4-D 0.5mg/L가 첨가된 배지에서 배양된 캘러스에서는 73.725 mg%를 함유하였으며 그 가운데 Glutamic acid가 26.555 mg%로서 가장 높게 나타났다. 총아미노산 함량에 대한 필수 아미노산의 함량 비율은 자연조건상태의 인경부분이 39.462 mg%를 함유하였고, 2,4-D 0.5mg/L가 첨가된 배지에서 배양된 캘러스에서는 13.072 mg%를 함유하고 있었다.

DentalVibe reduces pain during the administration of local anesthetic injection in comparison to 2% lignocaine gel: results from a clinical study

  • Joshi, Sagar;Bhate, Kalyani;Kshirsagar, Kapil;Pawar, Vivek;Kakodkar, Pradnya
    • Journal of Dental Anesthesia and Pain Medicine
    • /
    • 제21권1호
    • /
    • pp.41-47
    • /
    • 2021
  • Background: This study was designed to compare the efficacy of DentalVibe against 2% lidocaine gel in reducing pain during the administration of local anesthetic injection in the adult population. Methods: This was a split-mouth open-label, randomized, controlled clinical study conducted in the Department of Oral and Maxillofacial Surgery of a dental institute. Fifty patients who were scheduled for bilateral dental extractions requiring an inferior alveolar nerve block were enrolled in the study. Site A (n = 50) was coated with 2% lidocaine gel followed by a local anesthetic injection, and DentalVibe with local anesthetic injection was used for Site B (n = 50). The primary outcome was pain, which was recorded immediately after the administration of anesthetic injection using the Visual Analogue Scale [VAS 0 - 10]. Results: The VAS pain scores ranged from 4 to 10 for site A and 0 to 6 for site B. Comparison between the two sites showed a statistically significant difference [Mann-Whitney U test value = 51.50, P < 0.001] favoring site B. Conclusion: This study showed that DentalVibe reduces pain during injection of local anesthesia compared to topical anesthetic gel.

Effects of a specific blend of essential oils on apparent nutrient digestion, rumen fermentation and rumen microbial populations in sheep fed a 50:50 alfalfa hay:concentrate diet

  • Khateri, N.;Azizi, O.;Jahani-Azizabadi, H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제30권3호
    • /
    • pp.370-378
    • /
    • 2017
  • Objective: An experiment was conducted to investigate the effects of a specific mixture of essential oils (MEO), containing thyme, clove and cinnamon EO, on rumen microbial fermentation, nutrient apparent digestibility and blood metabolites in fistulated sheep. Methods: Six sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding MEO at 0 (control), 0.8, and 1.6 mL/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay:concentrate diet. Results: Ruminal pH, total volatile fatty acids (VFA) concentration, molar proportion of individual VFA, acetate: propionate ratio and methane production were not affected with MEO. Relative to the control, Small peptides plus amino acid nitrogen and large peptides nitrogen concentration in rumen fluid were not affected with MEO supplementation; while, rumen fluid ammonia nitrogen concentration at 0 and 6 h after morning feeding in sheep fed with 1.6 mL/d of MEO was lower (p<0.05) compared to the control and 0.8 mL/d of MEO. At 0 h after morning feeding, ammonia nitrogen concentration was higher (p<0.05) in sheep fed 0.8 mL/d of MEO relative to 1.6 mL/d and control diet. Ruminal protozoa and hyper ammonia producing (HAP) bacteria counts were not affected by addition of MEO in the diet. Relative to the control, no changes were observed in the red and white blood cells, hemoglobin, hematocrit, glucose, beta-hydroxybutyric acid, cholesterol, total protein, albumin, blood urea nitrogen and aspartate aminotransferase and alanine aminotransferase concentration. Apparent total tract digestibility of dry matter, crude proten, organic matter, and neutral detergent fiber were not influenced by MEO supplementation. Conclusion:The results of the present study suggested that supplementation of MEO may have limited effects on apparent nutrient digestibility, ruminal fermentation and protozoa and HAP bacteria count, blood cells and metabolites.

대일 수출용 진공포장 냉장등심의 유통기한 설정 (Establishment of Shelf-life of Vacuum Packaged Pork Loins for exporting to Japan)

  • 이무하
    • 한국축산식품학회지
    • /
    • 제18권2호
    • /
    • pp.115-124
    • /
    • 1998
  • This study was carried out investigate hygienic conditions of domestic packing plant for export and the shelf-life by Japanese standards. vacuum packaged chilled port loins provided by five packers(A, B, C, D and E) were transported to Japan in the same condition, Four packers(A, B, C adn d) produced the samples as hygienic as possible and one packer produced loins in the traditional hygienic condition, In TTC(2,3,5-triphenyl tetrazolium chloride) test all samples showed the negative reaction from the date of the quarantine(14 days after slaughtering) to 50 days The numbers of total plate count(TPC) of A, B, C and D packers that were below 108CFU/g until 50 days were accepted by Japanese Standards but TPC of E packer was over 107CFU/g at 30 days. VBN values increased sig-nificantly(P<0.01) in samples of A,B and D packers in the samples of C packer and E packer at 5% and 0.1% level respectively. The pH values of the vacuum packaged chilled pork for export at 14 days after slaughtering were 5.43∼6.00 In sensory evaluation, A, B, C and D packers which improved hygi-enic condition produced the products with good color and appearance. low drip until 40 days storage at $0^{\circ}C$ But as the storage time increase off-flavor occured at 40days in A and D packer and at 50days in B and C packer. In conclusion according to the above results of microbiological physicochemical and sensory evalution the edible periods of Korean vacuum package chilled porks may be estimated to 40∼50 days for the packers who improved hygienic condition and the shelf lives were calculated as 32∼40 days from edible period by a factor of 0.8(safety coefficient) while that of the pork from E packer which was produced in the traditional hygienic condition was estimated to 30 days after slaughtering at $0^{\circ}C$ Therefore the shelf-life of the pork of E packer would be only 24 days.

  • PDF

PHOSPHODIESTERASE 억제제 (PDE-1), SODIUM NITROPRUSSIDE, AMITRIPTYLINE, 및 CHLORPROMAZINE의 항-혈소판작용

  • 전보권;안상건;최상현;신경호;이민수;천연숙
    • 한국응용약물학회:학술대회논문집
    • /
    • 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
    • /
    • pp.286-286
    • /
    • 1994
  • Thrombin (0.25 U/ml : TB), 소-피부 collagen (200 $\mu\textrm{g}$/ml : CG), adenosine 5'-diphesphate (4,0 $\times$ $10^{-5}$M : ADP), 및 epinephrine (4,0 $\times$ 10 $^{-5}$M : EPI)의 가토-혈소판 응집과 단백인산화작용에 미치는 PDE-I (3-isobutyl-1-methylxanthine : IBMX, 및 KR 30075), amitriptyline (AP), chlorpromazine (CP), 및 sodium nitrogrosside (SNP)의 염향을 비교-검토하였다. 그 결과, KR은 2,2 $\times$ $10^{-7}$M 이하의 $IC_{50}$/에서 EPI > ADP > CG > TB 순으로 각각을 억제하였으며, SNP 보다도 강하였고; KR-30075보다 약하나 IBMX, AP, 및 CP도 각 응집재의 작용을 억제하였으며 특히 EPI에 대하여 $10^{-8}$M 이하의 $IC_{50}$/에서 유의한 억제력을 보였다. 각 응집제들은 41 kD 인산화는 유의하게 증가시키며 47 kD와 20 kD 단백인산화는 감소시켰는데; 모든 항응집성 약물이 41 kD 인산화-증가는 유의하게 억제하였다, 아울러, AP와 CP는 47 kD 단백인산화-감소에 영향을 미치지 않았으나 20 kD 단백인산화-감소는 억제하였다. PDE-I (IBMX와 KR)와 SNP는 47 kD와 20 kD 단백인산화-감소를 다소 약화시켰으며, 43 kD와 22 kD 단백인산화를 KR > IBMX > SNP순으로 유의하게 증가시켰고, KR의 22 kD 단백인산화작용은 현저하였다.

  • PDF

자외선에 의한 비타민 $D_3$ 합성과 직물(제2보) -동물 실험을 통하여 - (UVB Photosynthesis of Vit, D3 and Fabrics (Part ll) - The animal study -)

  • 김정현;안령미;송명견
    • 한국의류학회지
    • /
    • 제22권5호
    • /
    • pp.646-653
    • /
    • 1998
  • Because there is a great concern' today about the damaging effect of chronic exposure to sunlight the use of sunscreen providing the photoprotection effect against ultraviolet (UV) was widely increased. As a result of common use of level of photosynthetic Vit. D3 in human skin decreased these days. In our experiment the animals covered with fabrics with 50% (fabric B) and 100% (fabric A) protection rate against ultraviolet B (UVB) were used to measure serum 25(OH)D3, ALP, total clacium and phosphorus. Vitamin D deficiency diet group had no effect on concentration of serum phosphorus. But the concentrations of serum 25(OH)D9 and total calcium were more decreased in vitamin D deficiency diet rats than in normal diet rats. Alkaline phosphatase activity in sunlight irradiated groups covered with 50% (fabric B) and 100% (fabric A) WB protection fabrics was more significantly decreased than vitamin D deficiency diet group. In conclusion, sunlight irradiateted groups were compared to effective to protect born disease due to the Vit. D deficeincy group.

  • PDF