• Title/Summary/Keyword: DR system

Search Result 531, Processing Time 0.03 seconds

The study for electric readout of X-ray signal using MOSFET (MOSFET를 이용한 X선 신호의 전기적 획득에 관한 연구)

  • Park, S.K.;Kang, Y.S.;Seo, J.H.;Park, J.K.;Nam, S.H.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1998 no.11
    • /
    • pp.295-296
    • /
    • 1998
  • With xeroradiography appearance, DR (Digital Radiography) system have been studying for X-ray detection using photoreceptor. Also detection method for receptor charge change have been developing variably. We use photoreceptor material of a-Se(Amorphous Selenium) with high DQE, high SNR(Signal to Noise Ratio) and high transformation efficiency of X-ray signals into electrical signals. After a-Se receptor is uniformly charged by using Arc discharge, X-ray is exposed. Then a-Se receptor produce subtle charge variation and MOSFET detect charge variations. The detected signal pass A/D converter and signal processing by PC. As results, the initial voltage is 8V. It has wide dynamic range needed digital radiography system. In this study, we obtained data with changing kVp(tube potential voltage) and fixed 8mAs(tube current by exposure time) in X-ray system. However MOSFET detector for X-ray signal is not tested X-ray mAs variations. But if MOSFET detector is tested X-ray mAs variation and exactly calibrated multichannel is made and noise-reduction is done, suitable DR system readout method will be done.

  • PDF

The Professionalization of American Dental Hygienist (미국치과위생사의 전문직화에 대한 고찰)

  • Kim, Hyeong-Mi;Lim, Soon-Ryun;Bae, Hyun-Sook
    • Journal of dental hygiene science
    • /
    • v.14 no.3
    • /
    • pp.276-286
    • /
    • 2014
  • In 2013, dental hygienist is in its 100th year. As Dr. Fones opened two year dental hygiene training program at Bridgeport Junior College in 1913. 'Dental Hygienist', the profession that specializes in oral disease prevention and health science, was first used. Since 'Dental Hygienist' was first introduced in the States, looking back through the America's development of dental hygienist would be the basis of checking development process of the international dental hygiene system and comparing the system of each country. This study focused on the contemplation of how America's dental hygienist became professional through 'development of dental hygienist', 'development of dental hygiene education system', 'development of dental hygienist's license and related qualification system', 'Dental hygienist laws and ethics', and 'dental hygienists' role and scope'. America's dental hygienist has requirements to become professional and also dental hygienist is socially recognized as professional. Therefore, the purpose of this study is to investigate the process of American dental hygienist professionalization. Thus, references and literature were gathered and analyzed.

Seismic fragility curves for a concrete bridge using structural health monitoring and digital twins

  • Rojas-Mercedes, Norberto;Erazo, Kalil;Di Sarno, Luigi
    • Earthquakes and Structures
    • /
    • v.22 no.5
    • /
    • pp.503-515
    • /
    • 2022
  • This paper presents the development of seismic fragility curves for a precast reinforced concrete bridge instrumented with a structural health monitoring (SHM) system. The bridge is located near an active seismic fault in the Dominican Republic (DR) and provides the only access to several local communities in the aftermath of a potential damaging earthquake; moreover, the sample bridge was designed with outdated building codes and uses structural detailing not adequate for structures in seismic regions. The bridge was instrumented with an SHM system to extract information about its state of structural integrity and estimate its seismic performance. The data obtained from the SHM system is integrated with structural models to develop a set of fragility curves to be used as a quantitative measure of the expected damage; the fragility curves provide an estimate of the probability that the structure will exceed different damage limit states as a function of an earthquake intensity measure. To obtain the fragility curves a digital twin of the bridge is developed combining a computational finite element model and the information extracted from the SHM system. The digital twin is used as a response prediction tool that minimizes modeling uncertainty, significantly improving the predicting capability of the model and the accuracy of the fragility curves. The digital twin was used to perform a nonlinear incremental dynamic analysis (IDA) with selected ground motions that are consistent with the seismic fault and site characteristics. The fragility curves show that for the maximum expected acceleration (with a 2% probability of exceedance in 50 years) the structure has a 62% probability of undergoing extensive damage. This is the first study presenting fragility curves for civil infrastructure in the DR and the proposed methodology can be extended to other structures to support disaster mitigation and post-disaster decision-making strategies.

Preparation and Evaluation of New Adsorbent (Paper Sludge) in the Treatment of Waste Water of Textile Industry (섬유산업 폐수 처리시 새로운 종이슬러지 흡착제의 제조와 평가)

  • Elaziouti, A.;Laouedj, N.;Segheir, A.A.
    • Journal of the Korean Chemical Society
    • /
    • v.54 no.1
    • /
    • pp.115-119
    • /
    • 2010
  • Neutral red5 (BR 5) adsorption from aqueous solution was investigated. New solid adsorbent was prepared from paper sludge incinerated at $250^{\circ}C$ during 2 hours. Experiments were carried out, in batch system, to remove RB5 dye from the synthetic waste water. Maximum adsorption of 374.98 mg/g at pH 5, at room temperature and contact time of 80 min was obtained. The Langmuir and Freundlich adsorption models were applied to interpret the equilibrium isotherm. The Freundlich isotherm fits quite well with the experimental data (with highly regression coefficient $R^2$). The incinerated sludge solid samples untreated and treated with BR5 dye were characterized by FT-IR spectrophotometer.

The Usefulness Analysis of Applying Dose Mode in Mammography Women of Childbearing Age (가임기 여성의 유방촬영에서 Dose mode 적용의 유용성 분석)

  • Lee, So-Ra;Son, Soon-Lyong;Chung, Jae-Yoen;Lee, Kwan-Seob
    • Korean Journal of Digital Imaging in Medicine
    • /
    • v.15 no.2
    • /
    • pp.19-23
    • /
    • 2013
  • Purpose : Automatic exposure system(AOP mode) in DR Mammography of the STD and DOSE apply to women of childbearing age, the average glandular dose(AGD) and image quality by comparing was to demonstrate the usefulness of DOSE. Materials and Methods : Of the under 40 age 108 patients who visit to our hospital and examined STD and DOSE mammography from January 2008 to July 2013. AGD was obtained by DICOM header information provided by GE Senographe DS. STD and DOSE images were evaluated with obtained patients, Image J program was compared by calculating the SNR. Results : The average AGD of DOSE mode was 0.99mGy, and which decreased by 19% comparing to that of STD mode which was 1.18mGy. The two the average AGDs indicated statistically significant difference(p< .01). The average SNR of STD was 40.26, DOSE displayed, and to 39.68 in, there was no statistical significance. Results : The average AGD using DOSE mode which is one of DR mammography AOP modes decreased by comparing to that of STD mode showing no difference in image quality. The use of DOSE is considered to be useful.

  • PDF

A Study on the Principle of Rationalization in Fisheries Management (어업경영합리화의 원리에 대한 고찰)

  • 공용식
    • The Journal of Fisheries Business Administration
    • /
    • v.14 no.1
    • /
    • pp.1-18
    • /
    • 1983
  • This study has examined the principle of rationalization as a guiding principle in fisheries management. Generally speaking, the guiding principle of business management is the principle of profitability which is oriented to the profit maximization, but it has been insisted by Dr, Mohri that the principle of profitability should be translated into the maximization of ratio of added value on gross capital, According to Dr. Durcker, added value (contributed value) can be used to analyze productivity only if the allocation of costs which together make up the figures is economically meaningful. Therefore, the rationalization of fisheries management can be measured as a result of economic allocation of costs, The analysis of economic allocation of costs divides into macro-allocation of costs and micro-allocation of costs. In fisheries management, the former makes use of the analysis of break-even point, and the latter analyzes the efficiency of individual cost respectively and the state of division of costs which allocate into above-the-line expenses of lay system and management's burden expenses. In macro-allocation of costs, it is advisable that fixed costs be converted into variable costs. This is characteristically possible in fisheries management, because wages belong to variable costs in fisheries management while they are regarde as fixed cost in the other industires. Because we could find that all costs would belong to above-the-line expenses, in micro-allocation analysis, the very costs which are directly related to fisherman's poduction activity should be classified into above-the-line expenses, and the other costs into management's burden expenses. This is a central problem in the rationalization of fisheries management.

  • PDF

The Frequencies and Disease-Association of HLA Alleles in Bipolar Patients (양극성 장애환자에서 HLA 대립형의 빈도와 질병연관성)

  • Jun, Tae-Youn
    • Korean Journal of Biological Psychiatry
    • /
    • v.1 no.1
    • /
    • pp.79-87
    • /
    • 1994
  • For the purpose of evaluating the human leukocyte antigen(HLA) disease-association with bipolar disorder, HLA class I and class II allelic frequencies were assessed in 37 bipolar patients and were compared to the data from normal population. HLA class 1 typing was performed with microlymphocytotoxicity method while class II(DRB1) genotyping with reverse dot blot hybridization and sandwich method. Statistical analysis consisted of relative risk, Haldane's modified relative risk, Fisher's exact test and Bonferoni's corrected P. The results were as follows : 1) Bipolar patients showed increased allelic frequency of HLA A3 which has statistical significance. 2) Allelic frequencies of HLA B7, B14 and B54 were higher, while those of B51 and B55 were lower in bipolar patients, but they were not statistically significant. 3) Both of increased frequencies of DR2 in bipolar patients and DR15 in normal controls had statistical significance. The results of the present study suggested that some of HLA allelic types might be associated with bipolar disorder. To clarify the genetic influence of HLA to bipolar disorder, we should do consecutive study of bipolar disorder with new information about HLA system including alleles.

  • PDF

Growth and Characterization of Lithium Potassium Phthalate (LiKP) Single Crystals for Third Order Nonlinear Optical Applications

  • Sivakumar, B.;Raj, S. Gokul;Kumar, G. Ramesh;Mohan, R.
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.11
    • /
    • pp.3755-3760
    • /
    • 2012
  • Single crystals of lithium potassium phthalate (LiKP) were successfully grown from aqueous solution by solvent evaporation technique. The grown crystals were characterized by single crystal X-ray diffraction. The lithium potassium phthalate $C_{16}\;H_{12}\;K\;Li_3\;O_{11}$ belongs to triclinic system with the following unit-cell dimensions at 298(2) K;$a=7.405(5){\AA}$;$b=9.878(5){\AA}$;$c=13.396(5){\AA}$;${\alpha}=71.778(5)^{\circ}$;${\beta}=87.300(5)^{\circ}$;${\gamma}=85.405(5)^{\circ}$; having a space group P1. Mass spectrometric analysis provides the molecular weight of the compound and possible ways of fragmentations occurs in the compound. Thermal stability of the crystal was also studied by both simultaneous TGA/DTA analyses. The UV-Vis-NIR spectrum shows a good transparency in the whole of Visible and as well as in the near IR range. Third order nonlinear optical studies have also been studied by Z-scan technique. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated. The results have been discussed in detail.

A Study of Attached Biomass Back Washing in Fixed Film System (고정 생물막공법에서 부착미생물의 역세에 관한 연구)

  • 이창근;김정숙
    • Journal of Environmental Science International
    • /
    • v.6 no.3
    • /
    • pp.219-224
    • /
    • 1997
  • The cloging phenomenon in the fixed film reactor Is shown when biomass growth Is excessive for long operating time. In addition, effluent water Quality gets worse because of detachment of biomass. In this study, we conducted air-backwashing to sustain biomass In reactor to complement these defects. The results of experimental are showed In the following conclusion. The detachment rate was 19.5 - 38.0% when the organic loading rate was 0.40 - 1.32 kg COD/$m^3$/day, the k - backwashing Intensity was 2 L/min(6.7 $m^3$/$m^2$/hrl and the backwashing time was 15 - 19 seconds. And the detachment rate was 32.2 - 58.6 % when the organic loading rate was 1.37 - 2.27 kg COD/$m^2$/day, the backwashing time was 1 - 12 minutes. As orgnic loading rate and backwashing time ale Increased, detachment of fixed biomass Is Increased. The detachment equation with detachment rate(DR, %), backwashing time(BWT, min), fixed biomass concentration(FB. mg/L), and organic leading rate(OLR, kg COD/ms/day) through multiple linear regession was given by the following equation: DR : 17.964 $BWT^{0.1407} FB^{0.0597} OLR^{0.1946}$

  • PDF

Stochastic Gradient Descent Optimization Model for Demand Response in a Connected Microgrid

  • Sivanantham, Geetha;Gopalakrishnan, Srivatsun
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.16 no.1
    • /
    • pp.97-115
    • /
    • 2022
  • Smart power grid is a user friendly system that transforms the traditional electric grid to the one that operates in a co-operative and reliable manner. Demand Response (DR) is one of the important components of the smart grid. The DR programs enable the end user participation by which they can communicate with the electricity service provider and shape their daily energy consumption patterns and reduce their consumption costs. The increasing demands of electricity owing to growing population stresses the need for optimal usage of electricity and also to look out alternative and cheap renewable sources of electricity. The solar and wind energy are the promising sources of alternative energy at present because of renewable nature and low cost implementation. The proposed work models a smart home with renewable energy units. The random nature of the renewable sources like wind and solar energy brings an uncertainty to the model developed. A stochastic dual descent optimization method is used to bring optimality to the developed model. The proposed work is validated using the simulation results. From the results it is concluded that proposed work brings a balanced usage of the grid power and the renewable energy units. The work also optimizes the daily consumption pattern thereby reducing the consumption cost for the end users of electricity.