• 제목/요약/키워드: critical source area

검색결과 77건 처리시간 0.027초

몬테카를로 시뮬레이션을 이용한 복숭아의 방사선 조사 (Monte Carlo Simulation of Irradiation Treatment of Peaches (Prunus persica L. Batsch))

  • 김종순;김동현;박종민;최원식;권순홍
    • 한국산업융합학회 논문집
    • /
    • 제21권6호
    • /
    • pp.337-344
    • /
    • 2018
  • Food irradiation is important not only in ensuring safety but also improving antioxidant activity of peaches. Our objective was to establish the best irradiation treatment for peaches by calculating dose distribution using Monte Carlo simulation. 3-D geometry and component densities of peaches, extracted from CT scan, were entered into MCNP to obtain simulated dose distribution. Radiation energies for electron beam were 1.35 MeV (low energy) and 10 MeV (high energy). Co (1.25 MeV) and the Husman irradiator, containing three sealed Cs source rods in an annular array, were used for gamma irradiation. At 1.35 MeV electron beam simulation, electrons penetrated well beyond the peach skin, enough for surface treatment for microorganisms and allergens. At 10 MeV electron beam simulation, for top-beam only treatment, doses at the core were the highest and for double beam treatment, the electron energy was absorbed by the entire sample. At Co source, the radiation doses were presented on the whole area. At Cs source, the dose uniformity ratios were 2.78 for one source and 1.48 for three ones at 120 degrees interval. Proper control of irradiation treatment is critical to establish confidence in the irradiation process.

Identification of MgII Absorbers in the Quasar Lines of Sight

  • Shim, Hyunjin
    • 천문학회보
    • /
    • 제40권1호
    • /
    • pp.75.3-75.3
    • /
    • 2015
  • Large area infrared surveys are often accompanied with follow-up optical spectroscopic surveys that has a significant legacy value even for other areas of research. Using these spectral database, we have performed a search for MgII absorption lines in the optical spectrum of background quasar. Over the ~4deg2 of AKARI North Ecliptic Pole survey field and Spitzer First Look Survey field, 18 and 16 MgII absorber systems are identified respectively. The redshift range for the background quasars was 1.0<$z_{qso}$<3.4, while the redshift range for the absorber was 0.6<$z_{abs}$<1.6. Galaxies responsible for MgII absorptions are identified in the deep optical images (CFHT r-band), yet the identification still remains ambiguous for 60% of the systems due to the limited image depth and the source crowdedness. The impact parameter ranges 20-60kpc, and the rest-frame equivalent width of MgII absorption ranges $0.7-4{\AA}$. The most critical part in the identification of MgII absorber galaxies is the existence of deep optical images in addition to the high S/N quasar spectrum with R>3000.

  • PDF

Using DSP Algorithms for CRC in a CAN Controller

  • Juan, Ronnie O. Serfa;Kim, Hi Seok
    • IEIE Transactions on Smart Processing and Computing
    • /
    • 제5권1호
    • /
    • pp.29-34
    • /
    • 2016
  • A controller area network (CAN) controller is an integral part of an electronic control unit, particularly in an advanced driver assistance system application, and its characteristics should always be advantageous in all aspects of functionality especially in real time application. The cost should be low, while maintaining the functionality and reliability of the technology. However, a CAN protocol implementing serial operation results in slow throughput, especially in a cyclical redundancy checking (CRC) unit. In this paper, digital signal processing (DSP) algorithms are implemented, namely pipelining, unfolding, and retiming the CAN controller in the CRC unit, particularly for the encoder and decoder sections. It must attain a feasible iteration bound, a critical path that is appropriate for a CAN system, and must obtain a superior design of a high-speed parallel circuit for the CRC unit in order to have a faster transmission rate. The source code for the encoder and decoder was formulated in the Verilog hardware description language.

A COMPARISON OF METHOD FOR ESTIMATING FRACTIONAL GREEN VEGETATION COVER DERIVED FROM HYEPRION HYPERSPECTRAL DATA

  • Yoon, Yeo-Sang;Kim, Yong-Seung
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
    • /
    • pp.848-851
    • /
    • 2006
  • Green vegetation is one of the most critical factors for environment conditions thorough modulating evapotranspiration and absorption of solar radiation. Thus, fractional green vegetation cover (FVC) plays an important role in observing and managing environment. Remote sensing provides a seemingly obvious data source for quantifying FVC over large area. Therefore we compared a set of methods for estimating FVC using hyperspectral remote sensing data. For our study, we used Hyperion imagery acquired in April, 2002. In order to achieve our efforts, we analyzed simple NDVI-based method and spectral mixture analysis (SMA) models that were applied a variety of combinations of possible endmembers.

  • PDF

미활용에너지의 열 포텐셜 평가 수법에 관한 연구 (Study on Evaluation Method of Thermal Potential of Unused Energy)

  • 정용현
    • 한국환경과학회지
    • /
    • 제15권5호
    • /
    • pp.493-501
    • /
    • 2006
  • The increase in environmental loads and energy consumptions has resulted in the need of developed new forms of energy for a sustainable use for the society. Recently, the viability of using unused energy has attracted a great deal of attention. From the view point of using unused energy, the most critical problem can be referred to as the distance between the heat source/sink and heat demand area. The water resource in the city water system was used to solve this distance problem with unused energy. The calculation method of the potential use unit was used to survey the potential of the water resource in the city water system. The amount of theoretical unused energy and energy savings in the model city were estimated using this method. It is estimated that the amounts of energy savings and $CO_2$ reduction correspond to 131.3 GWh and 29280[t-C], respectively, per annual basis.

정보시스템 프로젝트의 위험요인에 대한 현업인력과 서비스제공인력과의 인식도 차이 (Perceptual Differences between IS Project Service Providers and Customers on Information System Project Risk Factors: a Koran case)

  • 이석준;조숙진;박정선;함유근;김용재
    • Journal of Information Technology Applications and Management
    • /
    • 제14권3호
    • /
    • pp.79-94
    • /
    • 2007
  • Cases of botched information systems implementation have been surfaced due to poor IS project management and control. One major source of such failures is the perceptual difference between the participants of IS projects who should define potential risk factors well before considered IS projects are launched. Based on risk factors cited from prior works, this paper empirically examines the risk factors associated with IS service project management to analyze perceptual differences between the IS service providers and customers in Korea. Data analyses found significant differences in the area of scheduling/resource, technological newness, communications, and sponsorship/ownership while statistically significant differences were observed in eleven individual factors out of forty six risk factors. Risk factors are also ordered in terms of perceived importance to highlight the critical differences.

  • PDF

Study on minerals status of dairy cows and their supplementation through area specific mineral mixture in the state of Jharkhand

  • Bhanderi, B.M.;Goswami, Ajay;Garg, M.R.;Samanta, Saikat
    • Journal of Animal Science and Technology
    • /
    • 제58권12호
    • /
    • pp.42.1-42.8
    • /
    • 2016
  • Background: Deficiency of macro and micro-minerals in the ration of dairy cows adversely affects growth, milk production and reproduction efficiency. It is essential to examine mineral concentrations in feeds offered to dairy cows in practical farms. Methods: Two villages from each taluka were selected at random for taking representative samples of feeds, forages and hair. Within the village, help was sought from village milk producers and district animal husbandry officer for identification of 4 to 5 farmers and collection of representative samples. All the samples were processed and analyzed for chemical composition as well as major macro and micro-minerals, using Inductively Coupled Plasma-Optical Emission Spectrometer. Results: Ca content in wheat straw (0.29%), crushed maize (0.02%) and wheat bran (0.12%) was found to be below the critical level (0.30%). The P content in concentrate ingredients was high (0.26-0.96%), but low in dry roughages (0.06-0.12%). Cereal straws (0.14%) and grains (0.12%) were deficient in Mg. Feeds and forages were found to be adequate in K (1.50%). Cereals straws were found to be deficient in S (0.11%). Greens were good source of Cu (12.02 ppm). Wheat straw was found to be low in Zn (18 ppm), but high in Mn (225 ppm) and Fe (509 ppm). Local grasses and azolla green were found to be rich source of Co (>1.00 ppm). Se (0.63 ppm) was present in appreciable quantities in most of the feedstuffs. Conclusions: From the present study, it was apparent that the feeds and forages available in the state of Jharkhand may not meet the requirements for Ca, P, Mg, Cu, Zn and Co in order to sustain a milk production of ~10 kg/day. Therefore, it is necessary to supplement these deficient minerals through area specific mineral mixture in the ration of dairy cows for improving productivity and reproduction efficiency.

진해만 입구해역의 표층 퇴적물 특성과 저서환경 (Surface Sediment Characteristics and Benthic Environments in the Mouth of Jinhae Bay, Korea)

  • 현상민;최진우;최진성;이태희
    • 한국수산과학회지
    • /
    • 제36권6호
    • /
    • pp.700-707
    • /
    • 2003
  • Surface sediments in the mouth area of Jinhae Bay were investigated to evaluate the benthic environment in terms of geochemical criteria and macrobenthos abundance. Characteristics of the surface sediment distribution exhibited muddy sediments in the most part of study area. Some mixed sediments of coarse sand and mud were distributed along the coastal area of Geoje Island and around the Jeo Islands. Organic matter from ignition loss and total organic carbon from CHNS varied between $8.8-1.7\%,\;and\;4.62-0.77\%,$ respectively. The source of organic matter based on the C/S ratio was mixed with in situ biogenic and terrigenous organic matter. The C/S ratio of organic matter also suggested both an anoxic bottom condition in several parts of the study area. The content of hydrogen sulfide in surface sediment was extremely variable and showed spatio-temporal variation from site to site. In several locations, the content of hydrogen sulfide as an index of eutrophication was over the critical value (0.2 mg/g), suggesting that several parts of the study area were not favorable for the habitat of macrobenthos. The relationship among the number of individuals of marcrobenthos, hydrogen sulfide, and organic matter was not clear, but a potential negative relationship between individuals of marcrobenthos and hydrogen sulfide was indicated.

The Significance of Caspase-Cleaved Cytokeratin 18 in Pleural Effusion

  • Lee, Keu Sung;Chung, Joo Yang;Jung, Yun Jung;Chung, Wou Young;Park, Joo Hun;Sheen, Seung Soo;Lee, Kyi Beom;Park, Kwang Joo
    • Tuberculosis and Respiratory Diseases
    • /
    • 제76권1호
    • /
    • pp.15-22
    • /
    • 2014
  • Background: Apoptosis plays a role in the development of pleural effusion. Caspase-cleaved cytokeratin 18, a marker for epithelial cell apoptosis, was evaluated in pleural effusion. Methods: A total of 79 patients with pleural effusion were enrolled. The underlying causes were lung cancer (n=24), parapneumonic effusion (n=15), tuberculous effusion (n=28), and transudates (n=12). The levels of M30, an epitope of caspase-cleaved cytokeratin 18, were measured in blood and pleural fluids using enzyme-linked immunosorbent assay along with routine cellular and biochemical parameters. The expression of M30 was evaluated in the pleural tissues using immunohistochemistry for M30. Results: The M30 levels in pleural fluid were significantly higher in patients with tuberculosis ($2,632.1{\pm}1,467.3U/mL$) than in patients with lung cancer ($956.5{\pm}618.5U/mL$), parapneumonic effusion ($689.9{\pm}413.6U/mL$), and transudates ($273.6{\pm}144.5U/mL$; all p<0.01). The serum levels were not significantly different among the disease groups. Based on receiver operating characteristics analysis, the area under the curve of M30 for differentiating tuberculous pleural effusion from all other effusions was 0.93. In the immunohistochemical analysis of M30, all pathologic types of cancer cells showed moderate to high expression, and the epithelioid cells in granulomas showed high expression in tuberculous pleural tissues. Conclusion: Caspase-cleaved cytokeratin 18 was most prominently observed in tuberculous pleural effusion and showed utility as a clinical marker. The main source of M30 was found to be the epithelioid cells of granulomas in tuberculous pleural tissues.

Grid Based Nonpoint Source Pollution Load Modelling

  • Niaraki, Abolghasem Sadeghi;Park, Jae-Min;Kim, Kye-Hyun;Lee, Chul-Yong
    • 한국공간정보시스템학회:학술대회논문집
    • /
    • 한국공간정보시스템학회 2007년도 GIS 공동춘계학술대회 논문집
    • /
    • pp.246-251
    • /
    • 2007
  • The purpose of this study is to develop a grid based model for calculating the critical nonpoint source (NPS) pollution load (BOD, TN, TP) in Nak-dong area in South Korea. In the last two decades, NPS pollution has become a topic for research that resulted in the development of numerous modeling techniques. Watershed researchers need to be able to emphasis on the characterization of water quality, including NPS pollution loads estimates. Geographic Information System (GIS) has been designed for the assessment of NPS pollution in a watershed. It uses different data such as DEM, precipitation, stream network, discharge, and land use data sets and utilizes a grid representation of a watershed for the approximation of average annual pollution loads and concentrations. The difficulty in traditional NPS modeling is the problem of identifying sources and quantifying the loads. This research is intended to investigate the correlation of NPS pollution concentrations with land uses in a watershed by calculating Expected Mean Concentrations (EMC). This work was accomplished using a grid based modelling technique that encompasses three stages. The first step includes estimating runoff grid by means of the precipitation grid and runoff coefficient. The second step is deriving the gird based model for calculating NPS pollution loads. The last step is validating the gird based model with traditional pollution loads calculation by applying statistical t-test method. The results on real data, illustrate the merits of the grid based modelling approach. Therefore, this model investigates a method of estimating and simulating point loads along with the spatially distributed NPS pollution loads. The pollutant concentration from local runoff is supposed to be directly related to land use in the region and is not considered to vary from event to event or within areas of similar land uses. By consideration of this point, it is anticipated that a single mean estimated pollutant concentration is assigned to all land uses rather than taking into account unique concentrations for different soil types, crops, and so on.

  • PDF