• Title/Summary/Keyword: quantitative evaluation method

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Quantitative and Pattern Recognition Analyses for the Quality Evaluationof Herba Epimedii by HPLC

  • Nurul Islam, M.;Lee, Sang-Kyu;Jeong, Seo-Young;Kim, Dong-Hyun;Jin, Chang-Bae;Yoo, Hye-Hyun
    • Bulletin of the Korean Chemical Society
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    • v.30 no.1
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    • pp.137-144
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    • 2009
  • In this study, quantitative and pattern recognition analyses for the quality evaluation of Herba Epimedii using HPLC was developed. For quantitative analysis, five major bioactive constituents, hyperin, epimedin A, epimedin B, epimedin C, and icariin were determined. Analysis was carried out on Capcell pak $C_{18}$ column ($250{\time}4.6$ mm, 5 ${\mu}m$) with a mobile phase of mixture of acetonitrile and 0.1% formic acid, using UV detection at 270 nm. The linear behavior was observed over the investigated concentration range (2-50 ${\mu}g/mL;\;r_2\;>$ 0.99) for all analytes. The intraand inter-day precisions were lower than 4.3% (as a relative standard deviation, RSD) and accuracies between 95.1% and 104.4%. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of one reference sample. The RSD of intra- and inter-day variation of relative retention time (RRT) and relative peak area (RPA) of the 12 selected common peaks were below 0.8% and 4.7%, respectively. The developed methods were applied to analysis of twenty Herba Epimedii extract samples. Contents of hyperin, epimedin A, epimedin B, epimedin C, and icariin were calculated to be 0$\sim$0.79, 0.69$\sim$1.91, 0.93$\sim$9.58, 0.65$\sim$3.05, and 2.43$\sim$11.8 mg/g dried plant. Principal component analysis (PCA) showed that most samples were clustered together with the reference samples but several apart from the main cluster in the PC score plot, indicating differences in overall chemical composition between two clusters. The present study suggests that quantitative determination of marker compounds combined with pattern-recognition method can provide a comprehensive approach for the quality assessment of herbal medicines.

On the Evaluation of the dynamic Safety of the Ship's Cargo at Sea (항해중 선박 적재화물의 동적 안정성 평가에 관한 연구)

  • 김철승;김순갑
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.3 no.1
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    • pp.33-49
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    • 1997
  • One of the most important missons that are imposed on merchant ship at sea is to accomplish the safe transportation of cargo loaded. Recently, a study on the seakeeping performance has been carried out on the development of evaluation system related to the synthetic safety of a ship at sea. The seakeeping performance is the ship's ability sailing at, and executing its misson against adverse environmental factors successfully and safely. Until now, however, there has not been any method of quantitative evaluation on the dynamic safety of the ship's cargo loaded. In this regards, this paper has introduced the evaluation method of dynamic safety of the ship's cargo. In order to evaluate the dynamic safety of cargo, the vertical and lateral acceleration which causes the collapse, racking and local structure failure of cargo was adopted as the evaluation factors in the ship's motions. The response amplitude of ship's motions in regular waves is manipulated by NSM (New Strip Method) on a given 2,700 TEU full container vessel under the wind forces of 7, 8 and 9 Beaufort scale. Each response of ship's motions induced by NSM was applied to short-crested irregular waves for stochastic process on evaluation factors and then vertical and lateral acceleration of each cargo was compared with significant amplitude of each acceleration. A representative dangerous factor was determined by comparing permissible values of stacking and racking forces occurred typically to the vertical and transverse directions with the container strength required on ISO 1496 at the positions of forecastle, poop and ship's midship respectively. Through the occurrence probability of the determined factor by Rayleigh's probability density function, the dangerousness which limits loads on container's side wall as an evaluation was applied in judging of the danger of the ship's cargo loaded.

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Experimental Study of the Free Roll Decay Test for the Evaluation of Roll Damping Coefficients (감쇠계수 산출을 위한 자유 횡동요 감쇠실험 연구)

  • Kim, Namwoo;Kim, Yong Jig;Ha, Youngrok
    • Journal of the Society of Naval Architects of Korea
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    • v.52 no.6
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    • pp.460-470
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    • 2015
  • In general ships and FPSOs, roll damping is very small and consequently roll motion is very large at the roll resonance frequency. Proper evaluation of the roll damping coefficient at the resonance frequency is an important task in the study of roll motion and usually it is done by the analysis of free roll decay tests. The relative decrement method based on energy relation has been used mainly for the evaluation of roll damping coefficient from the roll decay test so far. As another method, the logarithmic decrement method based on equivalent linear decay assumption can be used for the same purpose and it is relatively simple. In this paper, both of the relative decrement method and the logarithmic decrement method are used for the evaluation of roll damping coefficient including quadratic damping from the free roll decay tests, and their results are cross-checked for verifying the obtained damping coefficients. Through applications to a box-type floating body equiped with bilge keels, it is shown that the two methods give almost the same damping coefficients in a practical view point and the cross-check of their results is to be a good tool to prevent a possible error. And also the quantitative effects of the bilge keels on the roll damping of box-type floating body are shown and discussed.

Measurement of Orbit using Standardized Processing of CT Scan

  • Kim, Yong Oock
    • Journal of International Society for Simulation Surgery
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    • v.1 no.1
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    • pp.7-12
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    • 2014
  • Purpose Surgical correction of various occular problems which do not have visual problem in plastic surgical area is to normalize the appearance of the face by restoring the normal position of orbit and eyeball. With development of surgical technique, the orbit can be restored exactly in trauma patient and can be moved totally in hypertelorism, as an example of congenital disease. All these surgeries are based on the hypothesis that the position of oclular glove moves in the plane in a quantitatively predictable reationship to osseous orbit movement. However, no studies have critically evaluated between the change of periorbital soft tissue and the outcome of the surgical correction, because there is no method of objective, quantitave evaluation of the periorbital soft tissue. Method Author suggest the methodology for quantitative assessment of ocular and periocular fat changes using the manipulation of digital images of computed tomographic scan. Results The method was allowed to evaluate inter-dacryon distance, inter-centroid distance, movement of the medial orbital wall, movement of the lateral orbital wall, alteration of thickness of the lateral periorbital fat as indicator of movement of the orbital wall and orbit in the patient with congenital periorbital anomaly and postoperative periorbital surgery. The goal of surgical correction of various occular problems which do not have visual problem in plastic surgical area is to normalize the appearance of the face by restoring the normal position of orbit and eyeball. With development of surgical technique, the orbit can be restored exactly in trauma patient and can be moved totally in hypertelorism, as an example of congenital disease. All these sugeries are based on the hypothesis that the position of oclular glove moves in the plane in a quantitatively predictable relationship to osseous orbit movement. However, no studies have critically evaluated between the change of periorbital soft tissue and the outcome of the surgical correction, because there is no method of objective, quantitave evaluation of the periorbital soft tissue. In this report, author suggest the methodology for quantitative assessment of ocular and periocular fat changes using the manipulation of digital images of computed tomographic scan. Conclusion The method suggested is objective and accurate method in measurement of the orbital contents. It takes time and is not easy to do, however, this kind of measurement for fine structures will be more easily available in near future.

Creep Damage Evaluation of High-Temperature Pipeline Material for Fossil Power Plant by Ultrasonic Test Method (초음파에 의한 발전소 고온배관재료의 크리프손상 평가)

  • Lee, Sang-Guk;Chung, Min-Hwa
    • Journal of Ocean Engineering and Technology
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    • v.13 no.2 s.32
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    • pp.99-107
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    • 1999
  • Boiler high-temperature pipelines such as main steam pipe, header and steam drum in fossil power plants are degraded by creep damage due to severe operationg conditions which are high temperature and high pressure for an extended period time. Such material degradation leads to various component failures causing serious accidents at the plants. Conventional measurement techniques such as replica method, electric resistance method, and hardness test method have such disadvantages as complex preparation and measurement procedures, too many control parameters, and therefore, low practicality and they were applied only to component surfaces with good accessibility. In this paper, artificial creep degradation test and ultrasonic measurement for their creep degraded specimens have been carried out for the purpose of evaluation for creep damage which can occur in high-temperature pipeline of fossil power plant. Absolute measuring method of quantitative ultrasonic measurement for material degradation was established, and long term creep degradationtests using life prediction formula were carried out. As a result of ultrasonic tests for crept specimens, we confirmed that the sound velocity decreased and the attenuation coefficient linearly increased in proportion to the increase of creep fractiin(${\phi}$c).

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Quantitative evaluating method for diagnostic ultrasound probe using 3-dimensional acoustic field analysis (3차원 음장 분석법을 이용한 진단용 초음파 프로브의 정량적 성능평가)

  • Noh, Si-Cheol;Kim, Ju-Young;Park, Jae-Hyun;Kim, Jin-Su;Kang, Jung-Hoon;Choi, Heung-Ho
    • Journal of Sensor Science and Technology
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    • v.19 no.6
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    • pp.490-496
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    • 2010
  • In this study, in order to overcome the weakness of acoustic field analysis which is generally used for ultrasonic probe performance evaluation, automatic acoustic field measurement system and evaluation parameters were proposed. The comparisons between acoustic field simulation and measured acoustic distribution data of normal and abnormal channels were conducted to evaluate the availability of proposed system and evaluation parameters. First, the impulse response characteristic of sample probe was investigated to classify the normal elements and abnormal elements. And then, normal channels and abnormal channels with abnormal element were chosen. The suggested 12 evaluation parameters were calculated using the acoustic fields of these channels. The availability of proposed automatic acoustic field measurement system and evaluation parameters was confirmed. And the performance evaluation of ultrasonic probe using acoustic field analysis could be easier and faster.

Study on the Evaluation of Skill Level for Aircraft Body Assembly Workers (항공기 기체 조립 작업자 숙련도 평가 연구)

  • Hyoung Geun Kwon;Chie Hoon Song
    • Journal of the Korean Society of Industry Convergence
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    • v.27 no.3
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    • pp.535-546
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    • 2024
  • This research aims to develop a model to objectively and quantitatively measure the skill level of aircraft body assembly workers. Because aircraft body assembly is predominantly a manual process, skills management is a key factor of manufacturing competitiveness. Currently, skills management relies on the subjective judgment of supervisors, which lacks objectivity and reliability. As a remedy, this study proposed a systematic skill management model based on objective and quantitative evaluation criteria. By considering prior research, we developed an evaluation model that takes into account both expertise and versatility of a worker. The model selected five major tasks required for aircraft body assembly and established evaluation criteria considering the difficulty and maturity of each task. We then conducted a pilot evaluation with over 200 workers in four SMEs to validate the practicality and effectiveness of the model. Consequently, we identified and addressed the limitations of the existing evaluation method, subdivided the skill levels based on the performance capabilities of each task, and proposed a career growth path. The developed evaluation model offers critical data for executives and managers to determine work assignments, education, training, performance incentives, and wages. It is expected to enhance the attraction of new talent and systematize skills management in aviation manufacturing in the future.

Evaluation of the Modulation Transfer Function for Computed Tomography by Using American Association Physics Medicine Phantom (컴퓨터단층검사에서 AAPM Phantom을 이용한 변조전달함수 평가)

  • Kim, Ki-Won;Choi, Kwan-Woo;Jeong, Hoi-Woun;Jang, Seo-Goo;Kwon, Kyung-Tae;Son, Soon-Yong;Son, Jin-Hyun;Min, Jung-Whan
    • Journal of radiological science and technology
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    • v.39 no.2
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    • pp.193-198
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    • 2016
  • In clinical computed tomography (CT), regular quality assurance (QA) has been required. This study is to evaluate the MTF for analyzing the spatial resolution using AAPM phantom in CT exam. The dual source somatom definition flash (siemens healthcare, forchheim, Germany), the brilliance 64 (philips medical system Netherlands) and aquilion 64 (toshiba medical system, Japan) were used in this study. The quantitative evaluation was performed using the image J (wayne rasband national institutes of health, USA) and chart method which is measurement of modulation transfer function (MTF). In MTF evaluation, the spatial frequencies corresponding to the 50% MTF for the CT systems were 0.58, 0.28, and $0.59mm^{-1}$, respectively and the 10% MTF for the CT systems were 1.63, 0.89, and $1.21mm^{-1}$, respectively. This study could evaluate the characteristic of spatial resolution of MTF using chart method, suggesting the quantitative evaluation method using the data.

Quantitative Evaluation of Rehabilitation Therapy Based on a Two-Finger Force Measurement System

  • Kim, Gab-Soon
    • Journal of Sensor Science and Technology
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    • v.23 no.6
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    • pp.357-361
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    • 2014
  • This paper describes the evaluation of the effectiveness of rehabilitation therapy for patients with finger paralysis based on a two-finger force measurement system (TFFMS). The paralyzed fingers can be recovered through rehabilitation therapies. The finger pressing force of the patients can be measured utilizing the TFFMS previously developed by the author [7]. The TFFMS, however, has not been fully adopted as a standard method for evaluating the therapy owing to the lack of a standard protocol. The pressing force of healthy volunteers and patients is analyzed with the TFFMS to explore the feasibility of the TFFMS as an evaluation device. The test confirms that the established standard protocol is useful to quantitatively assess the progress of finger rehabilitation therapy.

Review on Library Science Research Evaluation in Korea (문헌정보학분야의 논문평가에 관한 고찰)

  • Lee Seung-Chae
    • Journal of Korean Library and Information Science Society
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    • v.36 no.4
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    • pp.199-210
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    • 2005
  • This study reviews the research papers which deal with research evaluation in library science and discusses on quantitative and qualitative research methods, and non-empirical research. For the purpose of improving paper production system, encouragement of publishing review paper and review Journal Is recommended.

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