• 제목/요약/키워드: SPL

검색결과 348건 처리시간 0.072초

Ensiling of Sweet Potato Leaves (Ipomoea batatas (L.) Lam) and the Nutritive Value of Sweet Potato Leaf Silage for Growing Pigs

  • An, Le Van;Lindberg, Jan Erik
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권4호
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    • pp.497-503
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    • 2004
  • The effect of adding carbohydrate-rich feedstuffs to sweet potato leaves (SPL) on silage quality was studied using a total of 180 laboratory silos. Silage quality was assessed by changes of pH, dry matter (DM), crude protein (CP) and ammonia nitrogen ($NH_{3}$-N). Pre-wilted SPL was mixed with cassava root meal (CRM), sweet potato root meal (SPM) or sugar cane molasses (Mo) at levels of 0, 30, 60 and 90 g $kg^{-1}$ (air-dry weight of additives to pre-wilted weight of SPL). Samples for assessing silage quality were collected after mixing the SPL with the additive and thereafter at 7, 14, 28 and 56 days of ensiling. There was a marked decrease in pH after 7 days and the pH remained low and stable until day 56. Addition of 60 and 90 g $kg^{-1}$ resulted in a lower pH (p<0.05) than the other treatments. The DM content of the silage increased (p<0.05) with increasing levels of additive, while there were no differences in DM with time of ensiling. The CP content of the silage decreased (p<0.05) with increasing levels of additive. The CP content did not change up to 28 days, but was lower (p<0.05) after 56 days in all treatments. The $NH_{3}$-N levels were increasing (p<0.05) with time of ensiling, and were lower (p<0.05) with additive levels of 60 g $kg^{-1}$ or higher. Also, the additive source affected the $NH_{3}$-N values, with the lowest values found for Mo. Castrated male pigs (Large White$\times$Mongcai) were used in 4$\times$4 Latin square design to study the total tract digestibility and nitrogen (N) utilisation of diets with inclusion of ensiled SPL. The diets were based on cassava root meal with inclusion of protein from either fish meal (C) or SPL ensiled with CRM (D1), SPL ensiled with SPM (D2) and SPL ensiled with Mo (D3). The digestibility of DM, organic matter (OM) and CP were higher (p<0.05), and the digestibility of crude fibre (CF) was lower (p<0.05), in diet C than in diets D1, D2 and D3. However, there were no differences (p>0.05) in digestibility of dietary components between diets D1, D2 and D3. Also, the excretion of N in faeces was higher (p<0.05) and the N retention was lower (p<0.05) in diets D1, D2 and D3 than in diet C. It can be concluded from the present experiments, that a good quality silage can be produced from pre-wilted SPL by addition of 60 g $kg^{-1}$ of either CRM, SPM or Mo. Diets with inclusion of 450 g ensiled SPL $kg^{-1}$ DM showed a high digestibility of dietary components and thus ensiled SPL should be considered as a potential feed resource for growing pigs.

Pass-by계측과 NCPX계측에 의한 주파수 별 음압 예측 모델 개발에 관한 연구 (A Study on Development of the Prediction Model Related to the Sound Pressure in Terms of Frequencies, Using the Pass-by and NCPX Method)

  • 김도완;문성호;안덕순;손현장
    • 한국도로학회논문집
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    • 제15권6호
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    • pp.79-91
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    • 2013
  • PURPOSES : The methods of measuring the sound from the noise source are Pass-by method and NCPX (Noble Close Proximity) method. These measuring methods were used to determine the linkage of TAPL (Total Acoustic Pressure Level) and SPL (Sound Pressure Level) in terms of frequencies. METHODS : The frequency analysis methods are DFT (Discrete Fourier Transform) and FFT (Fast Fourier Transform), CPB (Constant Percentage Bandwidth). The CPB analysis was used in this study, based on the 1/3 octave band option configured for the frequency analysis. Furthermore, the regression analysis was used at the condition related to the sound attenuation effect. The MPE (Mean Percentage Error) and RMSE (Root Mean Squared Error) were utilized for calculating the error. RESULTS : From the results of the CPB frequency analysis, the predicted SPL along the frequency has 99.1% maximum precision with the measured SPL, resulting in roughly 1 dB(A) error. The TAPL results have precision by 99.37% with the measured TAPL. The predicted TAPL results at this study by using the SPL prediction model along the frequency have the maximum precision of 98.37% with the vehicle velocity. CONCLUSIONS : The Predicted SPL model along the frequency and the TAPL result by using the predicted SPL model have a high level of accuracy through this study. But the vehicle velocity-TAPL prediction model from the previous study by using the log regression analysis cannot be consistent with the TAPL result by using the predicted SPL model.

Development of sound level meter provided with ultra-low SPL measuring function -Creation and evaluation of super-silent spaces-

  • Kawakami, Fukushi;Terazono, Shinichi;Lee, Ho-Gi
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2010년도 춘계학술대회 논문집
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    • pp.760-761
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    • 2010
  • As is widely known, SPL measurement using sound level meter (SLM) is limited to higher than 30 dBA, because of the self-noise n(x) of condenser microphone (CM). The authors confirmed n(x) is composed of 3 kinds, each of which is stable enough under the condition -20 ~ +50 deg C to eliminate the influence of n(x) by subtracting its energy from the squared input signal in the integration process, as well as to develop new type of SLM with ultra-low SPL measuring function. This is so-called "0-dB SLM" since it enables to measure SPL down to around 0 dB-SPL. The RMS of n(x) is acquired and stored in ROM in advance, by placing CM in the supersilent space or by using dummy microphone with equivalent capacitance before the actual measurements.

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SPL과 소프트 리소그래피를 이용한 나노 구조물 형성 연구 (Fabrication of Nanoscale Structures using SPL and Soft Lithography)

  • 류진화;김창석;정명영
    • 한국정밀공학회지
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    • 제23권7호
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    • pp.138-145
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    • 2006
  • A nanopatterning technique was proposed and demonstrated for low cost and mass productive process using the scanning probe lithography (SPL) and soft lithography. The nanometer scale structure is fabricated by the localized generation of oxide patterning on the H-passivated (100) silicon wafer, and soft lithography was performed to replicate of nanometer scale structures. Both height and width of the silicon oxidation is linear with the applied voltagein SPL, but the growth of width is more sensitive than that of height. The structure below 100 nm was fabricated using HF treatment. To overcome the structure height limitation, aqueous KOH orientation-dependent etching was performed on the H-passivated (100) silicon wafer. Soft lithography is also performed for the master replication process. Elastomeric stamp is fabricated by the replica molding technique with ultrasonic vibration. We showed that the elastomeric stamp with the depth of 60 nm and the width of 428 nm was acquired using the original master by SPL process.

폐기물 소각시설 내부 소음에 관한 연구 (A Study on Noise in Waste Facilities)

  • 서병석;박노국;전용한
    • 대한안전경영과학회지
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    • 제22권2호
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    • pp.15-21
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    • 2020
  • Industrial facilities need design to predict and reduce noise from design to prevent and reduce noise. The purpose of this study is to predict worker's environment and evaluate safety by analyzing noise inside underground blower room and air compressor room with fluid machinery in waste facility. This waste incineration facility was analyzed based on the ground floor, ground floor blower chamber, and air compressor chamber. The results of SPL(Sound Pressure Level) analysis at 1.5m away, which are frequently used to measure the SPL as a noise source, are as follows. SPL of basement level: 46.80[dB], SPL of ground layer: 48.57[dB]. As a result, it was expected that the noise level would be considerably lower than the 8 hours 50[dB] noise exposure per day.

Risk-sharing Strategies on EPC Contracts: Lessons-learned from Sabine Pass Liquefaction Project

  • Yoon, Sang-Moon;Lee, Jung-Heon;Lee, Eul-Bum
    • 국제학술발표논문집
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    • The 6th International Conference on Construction Engineering and Project Management
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    • pp.629-630
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    • 2015
  • 'Sabine Pass Liquefaction Project (SPL Project)', a case study in this report, is the first construction project of a U.S. liquefaction facility for shale gas export overseas. This study analyzes the SPL Project to give understanding and a guideline to Korean EPC companies by benchmarking about effective risk-sharing strategies on EPC contracts. This study consists of three parts. The first summarizes the liquefaction process adopted on the SPL Project, named the 'ConocoPhillips Optimized Cascade Process', and compares it with other competitive liquefaction processes. The second introduces the unique features of the SPL EPC contract by comparing it with two other EPC forms of contracts: a FIDIC Silver Book for onshore plant projects and a contract of an offshore oil production (FPSO) project. The third focuses on the complexity of project financing (PF), especially lenders control and impact on the EPC contract such as covenant provisions to constrain variations and changes on the EPC Contract. From these conclusions, it is anticipated that this case study can provide a guideline for successful performance of Korean EPC contractors overseas.

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매미나방(Lymantria dispar L.)의 저장단백질에 관한 연구 (A Study of Storage Protein in Lymantria dispar L.)

  • 원종엽;김학열
    • 한국동물학회지
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    • 제33권3호
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    • pp.346-353
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    • 1990
  • 두 종류의 저장단백질이 매미나방의 발생기간동안 혈림프와 지방체에서 발견되었다. SPl은 분자량이 440,000이며 6개의 동일한 subunit으로 구성되어 있다. 또한 SPl은 당과 지질을 함유한 복합단백질이며 그 등전점은 6.2이었다. SPl은 암수 모두 종령기간동안 비슷한 고농도를 보여 주었지만 번데기시기에는 암수가 상이한 패턴을 보여주었다. 즉 SPl은 수컷에서 점진적 감소를 보여준 반면 암컷에서는 점진적 증가를 보여주었다. SPl은 면역학적으로 난황단백질과 동일성을 보여 주었고, 미국흰불나방과 꿀벌부채나방의 저장단백질과 부분적인 동질성을 보여주었다.

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PTFE(Polytetrafluoroethylene) 라미네이팅 투습발수직물의 총음압 최소화를 위한 필름 타입 별 기본 특성과 역학 특성 (Basic and Mechanical Properties by Film Type to Minimize the Sound Pressure Level of PTFE Laminated Vapor-permeable Water-repellent Fabrics)

  • 이규린;이지현;진은정;양윤정;조길수
    • 한국의류산업학회지
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    • 제14권4호
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    • pp.641-647
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    • 2012
  • This study investigates the sound properties of fabric frictional sound (SPL, ${\Delta}L$, ${\Delta}f$) according to the film type of PTFE laminated vapor-permeable water-repellent fabrics in order to understand the relationship between SPL and the basic properties of fabrics such as layer, yarn type, and thickness of fiber. This study accesses their mechanical properties and determines how to control them to minimize SPL. Eight PTFE laminated water-repellent fabrics, composed of four different film types (A, B, C, D) and with two different fabrics, were used as test specimens. Frictional sounds generated at 1.21m/s were recorded by using a fabric sound generator and SPLs were analyzed through Fast Fourier Transformation (FFT). The mechanical properties of fabrics were measured by KES-FB. The SPL value was lowest at 74.4dB in film type A and highest as 85.5dB in type D. Based on ANOVA and post-hoc test, specimens were classified into less Loud Group (A, B) and Loud Group (C, D). It was shown that SPL was lower when 2 layer (instead of 3 layer), filament yarn than staple, and thin fiber than thick were used. In Group I, shearing properties (G, 2HG5), geometrical roughness (SMD), compressional properties (LC, RC) and weight (W) showed high correlation with SPL however, elongation (EM) and shear stiffness (G) did with SPL in Group II.