• 제목/요약/키워드: GUM approach

검색결과 27건 처리시간 0.02초

A study on the uncertainty of setpoint for reactor trip system of NPPs considering rectangular distributions

  • Youngho Jin;Jae-Yong Lee;Oon-Pyo Zhu
    • Nuclear Engineering and Technology
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    • 제56권5호
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    • pp.1845-1853
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    • 2024
  • The setpoint of the reactor trip system shall be set to consider the measurement uncertainty of the instrument channel and provide a reasonable and sufficient margin between the analytical limit and the trip setpoint. A comparative analysis was conducted to find out an appropriate uncertainty combination method through an example problem. The four methods were evaluated; 1) ISA-67.04.01 method, 2) the GUM95 method, 3) the modified GUM method developed by Fotowicz, and 4) the modified IEC61888 method proposed by authors for the pressure instrument channel presented in ISA-RP67.04.02 example. The appropriateness of each method was validated by comparing it with the result of Monte Carlo simulation. As a result of the evaluation, all methods are appropriate when all measurement uncertainty elements are normally distributed as expected. But ISA-67.04 method and GUM95 method overestimated the channel uncertainty if there is a dominant input element with rectangular distribution among the uncertainty input elements. Modified GUM95 methods developed by Fotowicz and modified IEC61888 method by authors are able to produce almost the same level of channel uncertainty as the Monte Carlo method, even when there is a dominant rectangular distribution among the uncertainty components, without computer-assisted simulations.

A Novel In Situ Gel Formulation of Ranitidine for Oral Sustained Delivery

  • Xu, Haoping;Shi, Min;Liu, Ying;Jiang, Jinling;Ma, Tao
    • Biomolecules & Therapeutics
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    • 제22권2호
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    • pp.161-165
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    • 2014
  • The main purpose of this study was to develop a novel, in situ gel system for sustained delivery of ranitidine hydrochloride. Ranitidine in situ gels at 0.2%, 0.5%, and 1.0% gellan gum concentration (w/v) were prepared, respectively, and characterized in terms of preparation, viscosity and in vitro release. The viscosity of the gellan gum formulations in solution increased with increasing concentrations of gellan gum. In vitro study showed that the release of ranitidine from these gels was characterized by an initial phase of high release (burst effect) and translated to the second phase of moderate release. Single photon emission computing tomography technique was used to evaluate the stomach residence time of gel containing $^{99m}Tc$ tracer. The animal experiment suggested in situ gel had feasibility of forming gels in stomach and sustained the ranitidine release from the gels over the period of at least 8 h. In conclusion, the in situ gel system is a promising approach for the oral delivery of ranitidine for the therapeutic effects improvement.

Development of an analytical method for the quantification of oleanonic acid from mastic gum using HPLC/PDA

  • Hak-Dong Lee;Chang-Dae Lee;So Yeon Choi;Sanghyun Lee
    • Journal of Applied Biological Chemistry
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    • 제66권
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    • pp.67-72
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    • 2023
  • A simple and accurate method was developed for the quantitative analysis of oleanonic acid (OA) from mastic gum. The analysis was carried out using reverse-phase high-performance liquid chromatography combined with a photodiode array detector (HPLC/PDA). Our optimized method was validated by measuring various parameters, using an INNO C18 column fitted with a gradient elution system. The results revealed limits of detection and quantification of 0.34 and 1.042 ㎍/mL, respectively. The OA calibration curve exhibited excellent linearity over the concentration range of 0.0625 to 2.0 mg/mL, with r2 =0.9996. Accuracy tests revealed a high recovery rate of 99.44-103.66%, with precision values below 0.15%. These results suggest that the present analytical method can identify and quantify OA in mastic gum with high precision. The HPLC approach developed in this study might be applied to routine analyses and large-scale extraction procedures for OA content quantification.

Pseudomonas elodea에 의한 Gellan Gum 생산(I) -metabolic parsmeter의 추정및 배양액의 유변학적 특성- (Production Of Gellan Gum by Pseudomonas elodea (I) -Estimation of Metabolic Parameters and Rheological Properties of Culture Broth-)

  • 정봉우;박선호
    • KSBB Journal
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    • 제5권3호
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    • pp.235-240
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    • 1990
  • Pseudomonas elodea 에 의한 Gellan gum생산시 이에 관련된 기초자료를 얻기 위하여 회분식 및 연속식 발효를 하였다. 회분식 배양의 결과로부터 비성장 속도는 $0.16hr^-^1$이었으며 72시간 배양후의 점도는 4500cp, 생성물 농도 0.7g dry weught/100g broth, 및 생산성은 0.08g dry weight/1/hr이었다. 연속식 배양을 통하여 최적 탄소원과 질소원의 농도비(3.0mg-carbon/mg-nitrogen)를 결정하였으며 Gellan gum의 최대 생성속도는 희석율 $0.14hr^-^1$에서 0.6g dry weight/l/hr이었다. 이러한 조건에서 각종 metabolic paeameter값을 계산하였다. 또한 배양액의 유변학적 특성은 Casson equation에 잘 부합됨을 확인하였고, 배양액의 점도와 산소전달계수를 측정하여 고점도 배양시 산소전달의 장애현상을 조사하였다.

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Characterization of starch and gum arabic-maltodextrin microparticles encapsulating acacia tannin extract and evaluation of their potential use in ruminant nutrition

  • Adejoro, Festus A.;Hassen, Abubeker;Thantsha, Mapitsi S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권7호
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    • pp.977-987
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    • 2019
  • Objective: The use of tannin extract and other phytochemicals as dietary additives in ruminants is becoming more popular due to their wide biological actions such as in methane mitigation, bypass of dietary protein, intestinal nematode control, among other uses. Unfortunately, some have strong astringency, low stability and bioavailability, and negatively affecting dry matter intake and digestibility. To circumvent these drawbacks, an effective delivery system may offer a promising approach to administer these extracts to the site where they are required. The objectives of this study were to encapsulate acacia tannin extract (ATE) with native starch and maltodextrin-gum arabic and to test the effect of encapsulation parameters on encapsulation efficiency, yield and morphology of the microparticles obtained as well as the effect on rumen in vitro gas production. Methods: The ATE was encapsulated with the wall materials, and the morphological features of freeze-dried microparticles were evaluated by scanning electron microscopy. The in vitro release pattern of microparticles in acetate buffer, simulating the rumen, and its effect on in vitro gas production was evaluated. Results: The morphological features revealed that maltodextrin/gum-arabic microparticles were irregular shaped, glossy and smaller, compared with those encapsulated with native starch, which were bigger, and more homogenous. Maltodextrin-gum arabic could be used up to 30% loading concentration compared with starch, which could not hold the core material beyond 15% loading capacity. Encapsulation efficiency ranged from $27.7%{\pm}6.4%$ to $48.8%{\pm}5.5%$ in starch and $56.1%{\pm}4.9%$ to $64.8%{\pm}2.8%$ in maltodextrin-gum arabic microparticles. Only a slight reduction in methane emission was recorded in encapsulated microparticles when compared with the samples containing only wall materials. Conclusion: Both encapsulated products exhibited the burst release pattern under the pH conditions and methane reduction associated with tannin was marginal. This is attributable to small loading percentages and therefore, other wall materials or encapsulation methods should be investigated.

Comparison of measurement uncertainty calculation methods on example of indirect tensile strength measurement

  • Tutmez, Bulent
    • Geomechanics and Engineering
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    • 제12권6호
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    • pp.871-882
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    • 2017
  • Indirect measure of the tensile strength of laboratory samples is an important topic in rock engineering. One of the most important tests, the Brazilian strength test is performed to obtain the tensile strength of rock, concrete and other quasi brittle materials. Because the measurements are provided indirectly and the inspected rock materials may have heterogeneous properties, uncertainty quantification is required for a reliable test evaluation. In addition to the conventional measurement evaluation uncertainty methods recommended by the Guide to the Expression of Uncertainty in Measurement (GUM), such as Taylor's and Monte Carlo Methods, a fuzzy set-based approach is also proposed and resulting uncertainties are discussed. The results showed that when a tensile strength measurement is measured by a laboratory test, its uncertainty can also be expressed by one of the methods presented.

영.한 음차 표기 성능 향상을 위한 음철법 기반 규칙 구축 (Phonics-based Rules for Improving Performance of English-to-Korean Transliteration)

  • 김민정;홍금원;박소영;임해창
    • 말소리와 음성과학
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    • 제1권4호
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    • pp.133-144
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    • 2009
  • This paper presents a method for constructing and using transliteration rules which are based on Phonics, an instructional method for speaking and writing English letters. Conventional approaches to automatic transliteration often focused on statistical methods. However, the construction or the collection of correct transliteration examples is always the bottleneck of the statistical transliteration model. Also, in practical domains where the collection of such data is very difficult, such as education and tourism, it is reasonable to build a system without much qualified data. Furthermore, compared with Korean orthography of borrowed foreign words, the proposed approach is much easier to construct, and can generate more refined rules. The experimentation result shows that the proposed approach can improve the performance of a statistical-based transliteration system.

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Fibric acid를 이용한 항고지혈증 겔 연고의 경피 흡수 특성 (Percutaneous absorption Characteristics of Anti hyperlipidemia Gel Ointment using Fibric acid)

  • 정덕채;황성규;오세영
    • 한국응용과학기술학회지
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    • 제27권4호
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    • pp.407-414
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    • 2010
  • New biological treatments were being developed at a record place, but their potential could be compromised by a significant obstacle: the delivery of these drugs into a body. Pharmaceutical delivery is now nearly as important as product. New systems are being developed, and Drug Delivery Markets Series cover these new systems. Transdermal Delivery System(TDS) is often used as a method of drug dosage into the epidermic skin. An approach used to delivery drugs through the skin for therapeutic use as an alternative to oral, intravascular, subcutaneous and transmucosal routes. Various transdermal drug delivery technologies are described including the use of suitable formulations, carriers and penetration enhancers. The most commonly used transdermal system is the skin patch using various types of technologies. Compared with other methods of dosage, it is possible to use for a long term. It is also possible to stop the drug dosage are stopped if the drug dosage lead to side effect. Polysaccharides, such as karaya gum and glucomannan, were selected as base materials of TDS. Also, these polymers were characterized in terms of enhancers, drug contents. Among these polysaccharide, the permeation rate of karaya gum matrix was fastest in fibric acid(ciprofibrate) such as lipophilic drug in vitro. We used glycerin, PEG400 and PEG800 as enhancers. Since dermis has more water content(hydration) than the stratum corneum, skin permeation rate at steady state was highly influenced when PEG400 was more effective for lipophilic drug. Proper selection of the polymeric materials which resemble and enhance properties of the delivering drug was found to be important in controlling the skin permeation rate. Especially, this result suggests a possible use of polysaccharide gel ointment matrix as a transdermal delivery system of anti-hyperlipoproteinemic agent.

Therapeutic effect of Ferula assa-foetida oleo-gum resin in rats with letrozole-induced polycystic ovary syndrome

  • Amir Shieh;Seyyed Majid Bagheri;Maryam Yadegari;Davoud Javidmehr;Zeinab Farhadi
    • Clinical and Experimental Reproductive Medicine
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    • 제49권4호
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    • pp.239-247
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    • 2022
  • Objective: Asafoetida is a gum derived from Ferula assa-foetida, which is used in traditional Iranian medicine to treat some reproductive system disorders. The effects of asafoetida on ovarian tissue, expression of certain genes associated with polycystic ovary syndrome (PCOS), and levels of liver, kidney, and blood cell factors after treatment in a rat model were investigated. Methods: Thirty rats were divided into five groups: normal, polycystic, and treatment with three doses of asafoetida (12.5, 25, and 50 mg/kg for 3 weeks after PCOS induction). PCOS was induced by letrozole at a dose of 1 mg/kg administered orally for 3 weeks. Blood samples were taken, and the ovaries were removed and prepared for histomorphometric examination. Liver and kidney parameters were measured. The mRNA expression levels of luteinizing hormone receptor, CYP11A1, adenosine monophosphate-activated protein kinase, adiponectin, and adiponectin receptors 1 and 2 were also measured by real-time polymerase chain reaction. Results: The levels of liver, kidney, and blood parameters did not significantly differ between the treatment groups and the control group. At doses of 25 and 50 mg/kg, ovarian histopathology, especially the thicknesses of the theca and granulosa layers, was significantly improved relative to the PCOS group. The expression of target genes also improved in the 25 and 50 mg/kg treatment groups. Conclusion: Asafoetida can be used to treat PCOS as a complementary approach to conventional therapies. Asafoetida appears to act by regulating and activating metabolic and ovarian cycle enzymes.

반복측정의 불확도를 이용한 인증값 확인 (Confirmation of reference value using uncertainty of multiple measurements)

  • 최종오;소헌영;우진춘;황의진
    • 분석과학
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    • 제15권6호
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    • pp.580-583
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    • 2002
  • New approach is developed employing the overall uncertainty obtained from multiple measurements to evaluate the statistical significance for the difference between a given reference value and its measured value determined in a lab. The overall uncertainty is determined by separate combinations of the uncertainties arising from systematic and random effects. It is shown that the uncertainty term in regular t-test can be underestimated by n measurements.