• Title/Summary/Keyword: Pretreatment verification

Search Result 13, Processing Time 0.026 seconds

Three-dimensional dose reconstruction-based pretreatment dosimetric verification in volumetric modulated arc therapy for prostate cancer

  • Jeong, Yuri;Oh, Jeong Geun;Kang, Jeong Ku;Moon, Sun Rock;Lee, Kang Kyoo
    • Radiation Oncology Journal
    • /
    • v.38 no.1
    • /
    • pp.60-67
    • /
    • 2020
  • Purpose: We performed three-dimensional (3D) dose reconstruction-based pretreatment verification to evaluate gamma analysis acceptance criteria in volumetric modulated arc therapy (VMAT) for prostate cancer. Materials and Methods: Pretreatment verification for 28 VMAT plans for prostate cancer was performed using the COMPASS system with a dolphin detector. The 3D reconstructed dose distribution of the treatment planning system calculation (TC) was compared with that of COMPASS independent calculation (CC) and COMPASS reconstruction from the dolphin detector measurement (CR). Gamma results (gamma failure rate and average gamma value [GFR and γAvg]) and dose-volume histogram (DVH) deviations, 98%, 2% and mean dose-volume difference (DD98%, DD2% and DDmean), were evaluated. Gamma analyses were performed with two acceptance criteria, 2%/2 mm and 3%/3 mm. Results: The GFR in 2%/2 mm criteria were less than 8%, and those in 3%/3 mm criteria were less than 1% for all structures in comparisons between TC, CC, and CR. In the comparison between TC and CR, GFR and γAvg in 2%/2 mm criteria were significantly higher than those in 3%/3 mm criteria. The DVH deviations were within 2%, except for DDmean (%) for rectum and bladder. Conclusions: The 3%/3 mm criteria were not strict enough to identify any discrepancies between planned and measured doses, and DVH deviations were less than 2% in most parameters. Therefore, gamma criteria of 2%/2 mm and DVH related parameters could be a useful tool for pretreatment verification for VMAT in prostate cancer.

Optimization of Two-stage Pretreatment from Soybean Hull for Efficient Glucose Recovery

  • Jung, Ji-Young;Choi, Myung-Suk;Yang, Jae-Kyung
    • Journal of the Korean Wood Science and Technology
    • /
    • v.40 no.2
    • /
    • pp.78-90
    • /
    • 2012
  • Soybean hull is an attractive feedstock for glucose production. To increase the glucose conversion in acid hydrolysis, a pretreatment method combined steam explosion with alkali pretreatment for soybean hull was studied. For first step pretreatment, steam explosion conditions (log Ro 2.45) were optimized to obtain maximum solid recovery and cellulose content. In the second step pretreatment, the conditions for potassium hydroxide pretreatment of steam exploded soybean hull were optimized by using RSM (response surface methodology). The optimum conditions for minimum lignin content were determined to be 0.6% potassium hydroxide concentration, $70^{\circ}C$ reaction temperature and 198 min reaction time. The predicted lignin content was 2.2% at the optimum conditions. Experimental verification of the optimum conditions gave the lignin content in similar value with the estimated value of the model. Finally, glucose conversion of pretreated soybean hull using acid hydrolysis resulted in $97.1{\pm}0.4%$. This research of two-step pretreatment was a promising method for increasing the glucose conversion in the cellulose-to-glucose process.

Improvement Particle and Physical Characteristics Applying of The Pretreatment Process System of Coal Gasification Slag and It's Verification Based on Statistical Approach (석탄 가스화 용융 슬래그의 전처리 공정 시스템 적용에 따른 입자 및 물리적 특성 개선 및 통계적 검증)

  • Kim, Jong;Han, Min-Cheol;Han, Jun-Hui
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.10 no.3
    • /
    • pp.285-292
    • /
    • 2022
  • The objective of this study is to investigate whether CGS generated in IGCC satisfies the fine aggregate quality items specified in KS F 2527(Concrete Aggregate) through the pretreatment process system and the quality improvement the system. The statistical significance of the pretreatment process was analyzed through Repeated Measurements ANOVA as measured values according to individually pretreatment process system. As a result of the analysis, In the case of CGS fine aggregate quality before and after the pretreatment process system, the density increased 5.2 %, the absorption rate decreased by 1.86 %, the 0.08 mm passing ratio decreased by 2.25 %, and Fineness Modulus and Particle-size Distribution were also found to be adjustable. It was found that the pretreatment process system was significant in improving the quality of CGS.

Verification of Silt Density Index (SDI) as a fouling index for reverse osmosis (RO) feed water (역삼투 공정 파울링 지표로서 SDI(Silt Density Index)의 적합성 검증)

  • Kim, Su-Han;Kim, Chung-H.;Kang, Suk-H.;Lee, Won-T.;Lim, Jae-L.
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.25 no.4
    • /
    • pp.489-495
    • /
    • 2011
  • Silt Density Index (SDI) has been used as a fouling index for reverse osmosis (RO) processes for decades. In order to decrease RO fouling, feed water should meet SDI standard, which was used to select a proper pretreatment system for RO processes. However, SDI is supposed to be sensitive only to particles larger than 0.45 ${\mu}m$ in terms of diameters while nanoparticles and dissolved organic matter can be potent foulants for RO processes. Our study started from the suspected performance of SDI as a RO fouling index. SDI data from pilot plants located world wide including South Korea were collected and analyzed. Suspended partcle concentration (i.e., turbidity and particle counts), and dissolved organic matter concentration (i.e., dissolved orgnaic carbon (DOC) concentration) data were also collected and compared to SDI values of same water samples. We found that SDI values were not only affected by suspended particle concentration but also by dissolved organic matter concentration. Therefore SDI can be used as a reasonable fouling index for RO feed water because the main foulants for RO processes are suspended particle and dissolved organic matter.

Classification of Red Wines by Near Infrared Transflectance Spectroscopy

  • W.Guggenbichler;Huck, C.W.;M.Popp;G.K.Bonn
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
    • /
    • 2001.06a
    • /
    • pp.1516-1516
    • /
    • 2001
  • During the recent years, wine analysis has played an increasing role due the health benefits of phenolic ingredients in red wine [1]. On the other hand there is the need to be able to distinguish between different wine varieties. Consumers want to know if a wine is an adulterated one or if it is based on the pure grape. Producers need to certificate their wines in order to ensure compliance with legal regulations. Up to now, the attempts to investigate the origin of wines were based on high-performance liquid chromatography (HPLC), gas chromatography (GC) and pyrolysis mass spectrometry (PMS) [l,2,3]. These methods need sample pretreatment, long analysis times and therefore lack of high sample throughput. In contradiction to these techniques using near infrared spectroscopy (NIRS), no sample pretreatment is necessary and the analysis time for one sample is only about 10 seconds. Hence, a near infrared spectroscopic method is presented that allows a fast classification of wine varieties in bottled red wines. For this, the spectra of 50 bottles of Cabernet Sauvignon, Lagrein and Sangiovese (Chianti) were recorded without any sample pretreatment over a wavelength range from 1000 to 2500 nm with a resolution of 12 cm$\^$-1/. 10 scans were used for an average spectrum. In order to yield best reproducibility, wines were thermostated at 23$^{\circ}C$ and a optical layer thickness of 3 mm was used. All recorded spectra were partitioned into a calibration and validation set (70% and 30%). Finally, a 3d scatter plot of the different investigated varieties allowed to distinguish between Cabernet Sauvignon, Lagrein and Sangiovese (Chianti). Considering the short analysis times this NRS-method will be an interesting tool for the quality control of wine verification and also for experienced sommeliers.

  • PDF

Optimization of KOH pretreatment conditions from Miscanthus using high temperature and extrusion system (고온 압출식 반응시스템을 이용한 억새 바이오매스의 KOH 전처리조건 최적화)

  • Cha, Young-Lok;Park, Sung-Min;Moon, Youn-Ho;Kim, Kwang-Soo;Lee, Ji-Eun;Kwon, Da-Eun;Kang, Yong-Gu
    • Journal of the Korean Applied Science and Technology
    • /
    • v.36 no.4
    • /
    • pp.1243-1252
    • /
    • 2019
  • The purpose of this study is to investigate the optimum conditions of biomass pretreatment with potassium hydroxide (KOH) for efficient utilization of cellulose, hemicellulose and lignin from Miscanthus. The optimization of variables was performed by response surface methodology (RSM). The variation ranges of the parameters for the RSM were potassium hydroxide 0.2~0.8 M, reaction temperature 110~190℃ and reaction time 10~90 min. The optimum conditions of alkali pretreatment from Miscanthus were determined as follows: concentration of KOH 0.47 M, reaction temperature 134℃ and reaction time 65 min. At the optimum conditions, the yield of cellulose from the solid fraction after pretreatment was predicted to be 95% by model prediction. Finally, 66.1 ± 1.1% of cellulose were obtained by verification experiment under the optimum conditions. The order contents of solid extraction were hemicellulose 26.4 ± 0.4%, lignin 3.7 ± 0.1% and ash 0.5 ± 0.04%. The yield of ethanol concentration of 96% was obtained using separated saccharification and fermentation.

An Empirical Study of the Clinically Reportable Range in Clinical Chemistry (임상보고 가능범위의 실증적 연구)

  • Chang, Sang-Wu;Lee, Sang-Gon;Choi, Ho-Seong;Song, Eun-Young;Park, Yong-Won;Lee, In-Ae
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.39 no.1
    • /
    • pp.31-36
    • /
    • 2007
  • The purpose of the clinically reportable range (CRR) in clinical chemistry is to estimate linearity in working range. The reportable range includes all results that may be reliably reported, and embraces two types of ranges: the analytical measurement range (AMR) is the range of analyte values that a method can directly measure on the specimen without any dilution, concentration, or other pretreatment not part of the usual assay process. CAP and JCAHO require linearity on analyzers every six months. The clinically reportable range is the range of analyte values that a method can measure, allowing for specimen dilution, concentration, or other pretreatment used to extend the direct analytical measurement range. The AMR cannot exceed the manufacturer's limits. Establishing AMR is easily accomplished with Calibration Verification Assessment and experimental Linearity. For example: The manufacturer states that the limits of the AST on their instrument are 0-1100. The lowest level that could be verified is 2. The upper level is 1241. The verified AMR of the instrument is 2-1241. The lower limit of the range is 2, because that is the lowest level that could be verified by the laboratory. The laboratory could not use the manufacturer's lower limit of 2 because they have not proven that the instrument values below 2 are valid. The upper limit of the range is 1241, because although the lab has shown that the instrument is linear to 1241, the manufacturer does not make that claim. The laboratory needs to demonstrate the accuracy and precision of the analyzer, as well the validation of the patient AMR. Linearity requirements have been eliminated from the CLIA regulations and from the CAP inspection criteria, however, many inspectors continue to feel that linearity studies are a part of good lab practice and should be encouraged. If a lab chooses to continue linearity studies, these studies must fully comply with the calibration/calibration verification requirements of CLIA and/or CAP. The results of lower limit and upper limit of clinically reportable range were total protein (2.1 - 79.9), albumin (1.3 - 39), total bilirubin (0.2 - 106.2), alkaline phosphatase (13 - 6928.2), aspartate aminotransferase (24 - 7446), alanine aminotransferase (13 - 6724.2), gamma glutamyl transpeptidase (16.64 - 9904.2), creatine kinase (15.26 - 4723.8), lactate dehydrogenase (127.66 - 13231.8), creatinine (0.4 - 129.6), blood urea nitrogen (8.67 - 925.8), uric acid (1.6 - 151.2), total cholesterol (48.52 - 3162), triglycerides (36.91 - 3367.8), glucose (31 - 4218), amylase (21 - 6694.2), calcium (3.1 - 118.2), inorganic phosphorus (1.11 - 108), HDL (11.74 - 666), NA (58.3 - 1800), K (1.0 - 69.6), CL (38 - 1230).

  • PDF

Dose Verification of Intensity Modulated Radiation Therapy with Beam Intensity Scanner System

  • Vahc, Young-Woo;Park, Kwangyl;Ohyun Kwon;Park, Kyung-Ran;Lee, Yong-Ha;Yi, Byung-Yong;Kim, Sookil
    • Proceedings of the Korean Society of Medical Physics Conference
    • /
    • 2002.09a
    • /
    • pp.248-251
    • /
    • 2002
  • The intensity modulated radiation therapy (IMRT) with a multileaf collimator (MLC) requires the conversion of a radiation fluence map into a leaf sequence file that controls the movement of the MLC during radiation treatment of patients. Patient dose verification is clinically one of the most important parts in the treatment delivery of the radiation therapy. The three dimensional (3D) reconstruction of dose distribution delivered to the target helps to verify patient dose and to determine the physical characteristics of beams used in IMRT. A new method is presented for the pretreatment dosimetric verification of two dimensional distributions of photon intensity by means of Beam Intensity Scanner System (BISS) as a radiation detector with a custom-made software for dose calculation of fluorescence signals from scintillator. The scintillator is used to produce fluorescence from the irradiation of 6MV photons on a Varian Clinac 21EX. The BISS reproduces 3D- relative dose distribution from the digitized fluoroscopic signals obtained by digital video camera-based scintillator(DVCS) device in the IMRT. For the intensity modulated beams (IMBs), the calculations of absorbed dose are performed in absolute beam fluence profiles which are used for calculation of the patient dose distribution. The 3D-dose profiles of the IMBs with the BISS were demonstrated by relative measurements of photon beams and shown good agreement with radiographic film. The mechanical and dosimetric properties of the collimating of dynamic and/or step MLC system alter the generated intensity. This is mostly due to leaf transmission, leaf penumbra and geometry of leaves. The variations of output according to the multileaf opening during the irradiation need to be accounted for as well. These phenomena result in a fluence distribution that can be substantially different from the initial and calculative intensity modulation and therefore, should be taken into account by the treatment planning for accurate dose calculations delivered to the target volume in IMRT.

  • PDF

A Study on the Development of Soil-based PTMs for Analysis of BTEX (BTEX 분석용 토양 숙련도 표준시료(PTMs) 개발에 관한 연구)

  • Lee, Minhyo;Lee, Guntaek;Lee, Bupyoel;Lee, Wonseok;Kim, Gumhee;Hong, Sukyoung
    • Journal of Soil and Groundwater Environment
    • /
    • v.18 no.5
    • /
    • pp.15-25
    • /
    • 2013
  • In this study, two kinds of soil-based proficiency testing materials (PTMs), NICE-012L and NICE-012R were prepared and certified for Benzen, Toluene, Etylbenzene and Xylene with evaluation of uncertainties. In order to analyse BTEX (Benzen Toluene Etylbenzene Xylene) for the candidate materials, GC/MS was used after pretreatment according to methods of soil analysis by Ministry of Environment. For the homogeneity test among bottles in terms of candidate materials, ISO 13528 and IUPAC Protocol were used and according to the result, both candidate materials showed sufficient homogeneity. Also, the stability test over the candidate materials was accessed according to the ISO Guide 35 by classifying short-term and long-term stability and the result showed that both candidate materials showed decent stability. The reference values of the two candidate materials depending on BTEX components were derived from the average of the 11 samples that were used for verification of the samples' homogeneity. Uncertainty of measurement was combined by uchar that was caused by a characteristic value, $u_{bb}$ that was caused by between-bottle homogeneity, and $u_{stab}$ that was caused by stability, and then combined uncertainty ($u_{PTM}$) was multiplied to the coverage factor (k) derived from the effective degree of freedom from each factor that leads to expanded uncertainty (U) in about 95% of confidence level. The proficiency testing materials developed through this study were supplied to National Institute of Environmental Research (NIER) and utilized as an external proficiency testing materials for evaluating analysis capacity of soil agencies with specialty in terms of soil analysis approved by Minister of Environment.

Feasibility study on the wide and long 9%Ni steel plate for use in the LNG storage inner tank shell

  • Chung, Myungjin;Kim, Jongmin;Kim, Jin-Kook
    • Steel and Composite Structures
    • /
    • v.32 no.5
    • /
    • pp.571-582
    • /
    • 2019
  • This study aimed to assess the feasibility on the wide and long 9%Ni steel plate for use in the LNG storage inner tank shell. First, 5-m-wide and 15-m-long 9%Ni steel plates were test manufactured from a steel mill and specimens taken from the plates were tested for strength, toughness, and flatness to verify their performance based on international standards and design specifications. Second, plates with a thickness of 10 mm and 25 mm, a width of 4.8~5.0 m, and a length of 15 m were test fabricated by subjecting to pretreatment, beveling, and roll bending resulting in a final width of 4.5~4.8 m and a length of 14.8m with fabrication errors identical to conventional plates. Third, welded specimens obtained via shield metal arc welding used for vertical welding of inner tank shell and submerged arc welding used for horizontal welding were also tested for strength, toughness and ductility. Fourth, verification of shell plate material and fabrication was followed by test erection using two 25-mm-thick, 4.5-m-wide and 14.8-m-long 9%Ni steel plates. No undesirable welding failure or deformation was found. Finally, parametric design using wide and long 9%Ni steel plates was carried out, and a simplified design method to determine the plate thickness along the shell height was proposed. The cost analysis based on the parametric design resulted in about 2% increase of steel weight; however, the construction cost was reduced about 6% due to large reduction in welding work.