• 제목/요약/키워드: Different sources

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실생활 충격소음을 통한 표준 바닥충격원의 실효성 검증 (Verification of Effectiveness of the Standard Floor Impact Source by Comparing with Living Impact Sources)

  • 박현구;김경모;김선우
    • 한국소음진동공학회논문집
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    • 제23권12호
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    • pp.1117-1126
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    • 2013
  • The standard impact sources, standardized to rate the sound insulation performance of floor structure, should simulate well the real floor impact sources, which is very important to grade the floor structure then to establish counter plan to improve the performance of floor. Recently the tire, the standard heavyweight impact source, has been discussed that the impact force is too big to represent the real impact force. And researches have been carried on the applicability as a substitute or a supplementary. In addition, tapping machine, the standard lightweight impact source, is also questionable if it is representative of real lightweight impact source. This study aims to examine the similarity of standard impact sources with living impact sources, comparing the physical characteristics such as impact force, frequency contents and sound level. The result showed that the physical characteristics of standard impact sounds were somewhat different with that of living impact sounds, and the standard sources couldn't be verified from this result. Later subjective evaluation should be followed to compare how the physical differences make relationship with the subjective differences.

개선된 이동 프레임 음향 홀로그래피 방법과 이동 음원의 방사 소음의 가시화에 대한 응용 (Review of the Improved Moving Frame Acoustic Holography and Its Application to the Visualization of Moving Noise Sources)

  • 박순홍;김양한
    • 소음진동
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    • 제10권4호
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    • pp.669-678
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    • 2000
  • This paper reviews the improved moving frame acoustic holography (MFAH) method and its application. Moving frame acoustic holography was originally proposed to increase the aperture size and the spatial resolution of hologram by using a moving line array of microphones. The hologram of scanned plane can be obtained by assuming the sound field to be product of spatial and temporal information. Although conventional MFAH was only applied to sinusoidal signals, it allows us to visualize the noise generated by moving noise sources by employing a vertical line array of microphones affixed to the ground. However, the sound field generated by moving sources becomes different from that of stationary ones due to the movement of the sources. Firstly, this paper introduces the effect of moving noise sources on the obtained hologram by MFAH and the applicability of MFAH to the visualization of moving sources. Secondly, this paper also reviews improved MFAH that can visualize a coherent narrow band noise and a pass-by noise. The practical applicability of the improved MFAH was demonstrated by visualizing tire noise during a pass-by test.

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Opportunities and Challenges in Metals Recovery from Secondary Sources - US Perspective

  • Han, Kenneth N.
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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    • pp.3-8
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    • 2001
  • The mineral industry of the United States is going through a challenging time. The US as an industrial nation faces with increasing demand in raw materials to fuel various industrial sectors but, at the same time, meeting environmental constraints associated with excavating and extracting these raw materials. In addition, gradual depletion of material resources. and the necessity of handling more complex forms of resources of primary origin have led to a decline in her resource productivity, once a strategic advantage of the U.S. As a result. the United States currently relies heavily upon foreign importation of various materials such as precious and strategic metals. However, since the US is the major consumer of most of these materials, the recovery of these values from scrap would help renew her position as a resource-producing nation, and ultimately help spur its domestic economy. Furthermore. recycling would also help maintain a clean environment and reduce energy consumption. In this paper. the author attempts to discuss opportunities and challenges lied ahead of the US mineral in relation to recovering their much-needed resources from secondary sources. The need and demand in various metals in the US will be reviewed and discussed. The implication of resource recovery from secondary sources will also be discussed. Extraction methods treating secondary sources are inherently different from those for primary sources. There is a need for new technologies which are metallurgically efficient and environmentally benign in treating secondary sources. Ways to meet such a need will be examined and key factors to be considered in approaching these challenges will be discussed.

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완주지역의 VOCs 배출특성에 따른 공단지역과 일반지역의 기여도 분석 (VOCs Emission Characteristics and Mass Contribution Analysis at Wanju Industrial Area)

  • 김득수;양고수;박비오
    • 한국대기환경학회지
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    • 제24권5호
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    • pp.562-573
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    • 2008
  • Concentrations of volatile organic compounds (VOCs) measured from the local industrial sources in Wanju industrial complex during June $2007{\sim}January$ 2008. The samples were collected from the primary sources (6 emission points) in 4 major factories in Wanju industrial complex as well as two general sources in Wanju County to elucidate the abundances of speciated VOCs and their spacial and temporal distributions depending on source bases. Industrial sources are as follows; fabricated metal manufacture, motor vehicle manufacture, rubber and plastic manufacture, and chemical manufacture factories. Two general source samples were collected from gasoline gas station and dry cleaning shop in urban area. In order to understand the near source influence at receptor, samples from the two receptor sites (one is at center of the industrial complex and the other site is at distance residential area downwind from the center) were collected with sample canister, and analyzed by using GC/MSD. The concentrations from different sources were compared and discussed. The mass contributions of the speciated VOCs to total VOCs measured from industrial sources and ambient ai r at two receptors were presented and discussed.

Favorable Culture Conditions for Mycelial Growth of Korean Wild Strains in Ganoderma lucidum

  • Jayasinghe, Chandana;Imtiaj, Ahmed;Hur, Hyun;Lee, Geon-Woo;Lee, Tae-Soo;Lee, U-Youn
    • Mycobiology
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    • 제36권1호
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    • pp.28-33
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    • 2008
  • Ganoderma lucidum (Fr.) Karst (Polyporaceae), belonging to basidiomycota, is one of the most famous medicinal mushrooms. This study was carried out to investigate favorable mycelial growth conditions, such as pH, temperature, growth media, carbon sources and nitrogen sources of Korean strains in G. lucidum. The most suitable temperature for the mycelial growth was obtained at $30^{\circ}C$. In general, optimal temperature range for the mycelial growth was found at $25{\sim}30^{\circ}C$. This Mushroom has a broad pH range ($5{\sim}9$) for its mycelial growth and mostly favorable growth was found at pH 5. Generally, Hamada, Glucose peptone, YM, Mushroom complete and Lilly media were the most suitable for the mycelial growth of G. lucidum. Among 10 different carbon sources, dextrin, galactose and fructose were best but the rest of other carbon sources also facilitated the growth of mycelia. The most suitable nitrogen sources were ammonium acetate, glycine, arginine and calcium nitrate, but to a certain extent, all of the supplemented nitrogen sources also stimulated the mycelial growth.

한강수계 굴포천과 안양천에서 안정동위원소와 수질 특성을 이용한 입자성 물질의 기원 추적 (Source Tracking of Particular Matters using Stable Isotope Analysis and Water Quality Characteristics in Gulpo and Anyang Stream, Han-River)

  • 홍정기;임종권;손주연;노혜란;유순주;이보미
    • 한국물환경학회지
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    • 제36권2호
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    • pp.116-124
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    • 2020
  • This study aims to identify the characteristics of organic matter and pollutant sources using water quality and stable isotope ratios (δ15N, δ13C) of the two inflow tributaries (Gulpo (GP) and Anyang (AY) streams). Water samples were analyzed in June and September 2018, and the results showed that the concentrations of nutrients, such as TN and NO3-N, were increased at GP4, which is located at the downstream of sewage treatment facilities(STFs). TOC and TN ratios showed a strong positive correlation (R2 = 0.77, p<0.01) at all points except for GP4. The results of GP's stable isotope ratio analysis do not appear to be a constant cluster compared to AY because GPs with large amounts of pollutants from the industry (metal processing companies, etc.) have less tributary, shorter waterway and significantly different external sources. This could be attributed to different sources of external inflow despite its smaller number of tributaries and shorter waterways than AY. In the first half of the year, the δ155N of GP4 was affected by discharge of STFs, while AY3 seemed to have an influence of tributary than the discharge of STFs. Consequently, using water quality, stable isotope ratio and C/N, the sources of contamination in two streams with different contaminants were identified and origin was estimated.

친환경 흑염소 사양을 위한 최적 조사료 초종 및 TMR 혼합비 비율: In vitro 반추위 발효 연구 (Optimum Forage Sources and Its Ratio in TMR for Environmently-friendly Goat Feeding: In vitro Rumen Fermentation Study)

  • 류채화;이진욱;김관우;이성수;박혜련;전은정;박명선;최낙진
    • 한국유기농업학회지
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    • 제28권4호
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    • pp.605-614
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    • 2020
  • This study was conducted to investigate the effects of TMR on in vitro rumen fermentation and methane production of goat with different forage sources. The experiment was arranged 4×2 factorial design. The different forage sources were rice straw (RS), Italian rye grass (IR), timothy (TI) and alfalfa (AL), respectively. There were two different forage : concentrate ratios such as 20:80 (20) and 50:50 (50), respectively. Therefore, totally 8 treatments were used: 1) RS20, 2) RS50, 3) IR20, 4) IR50, 5) TI20, 6) TI50, 7) AL20, and 8) AL50, respectively. The rumen fluid of goat was collected from the slaughterhouse. For fermentation parameters, ruminal pH, total gas, methane, hydrogen, ammonia nitrogen, and volatile fatty acid were determined. The pH values were within an optimal range across all treatments. Total gas productions at TI20 and AL50 were significantly greater than others (p<0.05). Methane production was significantly lower in TI and AL compared with other treatments (p<0.05). The relatively high dietary NDF content in treatments showed significantly lower methane production (p<0.05). Significant alterations treatments were detected at ammonia nitrogen concentration according to the ratio of forage : concentrate (p<0.05). AL treatment showed greater total volatile fatty acid production compared with other treatments (p<0.05). Therefore, the present study suggests that both Timothy and Alfalfa could be recommendable forage sources for goat based on results with volatile fatty acid as an energy source and methane as an index for energy loss and environmental issues. Also, the 50:50 (forage : concentrate) ratio would prefer to 20:80.

Pathogenic Diversity of Ascochyta rabiei Isolates and Identification of Resistance Sources in Core Collection of Chickpea Germplasm

  • Farahani, Somayeh;Talebi, Reza;Maleki, Mojdeh;Mehrabi, Rahim;Kanouni, Homayoun
    • The Plant Pathology Journal
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    • 제35권4호
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    • pp.321-329
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    • 2019
  • Ascochyta blight caused by Ascochyta rabiei (Pass.) Lab. (Telomorph: Didymella rabiei) (Kov.) is one of the most important fungal diseases in chickpea worldwide. Knowledge about pathogen aggressiveness and identification resistance sources to different pathotypes is very useful for proper decisions in breeding programs. In this study, virulence of 32 A. rabiei isolates from different part of Iran were analyzed on seven chickpea differentials and grouped into six races based on 0-9 rating scale and susceptibility/resistant pattern of chickpea differentials. The least and most frequent races were race V and race I, respectively. Race V and VI showed highly virulence on most of differential, while race I showed least aggressiveness. Resistance pattern of 165 chickpea genotypes also were tested against six different A. rabiei races. ANOVA analysis showed high significant difference for isolate, chickpea genotypes and their interactions. Overall $chickpea{\times}isolate$ (race) interactions, 259 resistance responses (disease severity ${\leq}4$) were identified. Resistance spectra of chickpea genotypes showed more resistance rate to race I (49.70%) and race III (35.15%), while there were no resistance genotypes to race VI. Cluster analysis based on disease severity rate, grouped chickpea genotypes into four distinct clusters. Interactions between isolates or races used in this study, showed the lack of a genotype with complete resistance. Our finding for virulence pattern of A. rabiei and newly identified resistance sources could be considerably important for integration of ascochyta blight resistance genes into chickpea breeding programs and proper decision in future for germplasm conservation and diseases management.

Sustainable Management of Irrigation Water Withdrawal in Major River Basins by Implementing the Irrigation Module of Community Land Model

  • Manas Ranjan Panda;Yeonjoo Kim
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2023년도 학술발표회
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    • pp.185-185
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    • 2023
  • Agricultural water demand is considered as the major sector of water withdrawal due to irrigation. The majority part of the global agricultural field depends on various irrigation techniques. Therefore, a timely and sufficient supply of water is the most important requirement for agriculture. Irrigation is implemented in different ways in various land surface models, it can be modeled empirically based on observed irrigation rates or by calculating water supply and demand. Certain models can also calculate the irrigation demand as per the soil water deficit. In these implementations, irrigation is typically applied uniformly over the irrigated land regardless of crop types or irrigation techniques. Whereas, the latest version of Community Land Model (CLM) in the Community Terrestrial Systems Model (CTSM) uses a global distribution map of irrigation with 64 crop functional types (CFTs) to simulate the irrigation water demand. It can estimate irrigation water withdrawal from different sources and the amount or the areas irrigated with different irrigation techniques. Hence, we set up the model for the simulation period of 16 years from 2000 to 2015 to analyze the global irrigation demand at a spatial resolution of 1.9° × 2.5°. The simulated irrigation water demand is evaluated with the available observation data from FAO AQUASTAT database at the country scale. With the evaluated model, this study aims to suggest new sustainable scenarios for the ratios of irrigation water withdrawal, high depending on the withdrawal sources e.g. surface water and groundwater. With such scenarios, the CFT maps are considered as the determining factor for selecting the areas where the crop pattern can be altered for a sustainable irrigation water management depending on the available withdrawal sources. Overall, our study demonstrate that the scenarios for the future sustainable water resources management in terms of irrigation water withdrawal from the both the surface water and groundwater sources may overcome the excessive stress on exploiting the groundwater in major river basins globally.

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효소원을 달리한 노치의 품질 변화 (Quality Characteristics of Nochies Saccharified by Amylases from Various Sources)

  • 이종미;윤희정
    • 한국식품조리과학회지
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    • 제12권4호
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    • pp.522-534
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    • 1996
  • The present study was conducted to investigate quality characteristics of Nochi made with malted barley flour with (Cl) and without hull (C2), comparing with Nochi that was treated with different sources of commercial amylases. There was higher level of moisture content (18.4%) in Nochi treated with fungal ${\alpha}$-amylase (FU) comparing with the other Nochi samples. However, Nochi that was treated with bacterial ${\alpha}$-amylase and ${\beta}$-amylase (BA-${\beta}$) had the lowest level of moisture content (11.2%). Nochi samples which were treated with thermostable ${\alpha}$-amylase and fungal ${\alpha}$-amylase(TE-FU) were different from traditional Nochi samples in mechanical characteristics. According to the results of sensory evaluation, Cl was similar to C2 except in cohesiveness and malt flavor. TE-FU and Bh-${\beta}$ were not different from traditional Nochi in cohesiveness, sweetness and overall desirability.

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