• Title/Summary/Keyword: Field Trial

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Efficiency measuring in pump using Thermodynamic method (열역학법에 의한 펌프의 수력효율측정)

  • Kwon, Young June;Seo, Chang Deok;Jung, Yong Chea;Park, Jang Won
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.546-551
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    • 2004
  • An applying Thermodynamic method for the purpose of measuring hydraulic efficiency of pump-motor system, based on IEC60041 code, is not easy to adopt at field test. Even though there were splendid development in measuring technic in discharge measuring through the hydraulic machina lots of unsolved problems concerned in flow-rate are still remain in measuring hydraulic efficiency in hydraulic machine. The key point in measuring hydraulic efficiency is to measure exact flow-rate. So, Thermodynamic methode provides a good solution. This methode measures hydraulic efficiency by detecting the difference of temperature and pressure between the hydraulic process of machine, without measuring flow-rate of pump or turbine. By measuring temperature in mk level and absolute pressure in pascal, we can get a difference of thermodynamic specific energy in Moliere chart before and after of hydraulic process, md that difference is equal to hydraulic loses. Following the standard in proceeding Thermodynamic methode, I hope these trial and records make others be familiar to the thermal methode and make it easer to beginner for trial.

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Clinical trial of Aromatherapy on Postpartum Mother′s Perineal Healing (아로마테라피가 산모의 회음부 치유에 미치는 효과)

  • 허명행;한선희
    • Journal of Korean Academy of Nursing
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    • v.34 no.1
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    • pp.53-62
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    • 2004
  • Purpose This study was designed to verify the effect of aromatherapy on a postpartum mother's perineal healing. Method The research design was a clinical trial. The methods of aromatherapy were applied sitz bath or soap application using essential oils with Lavender, Myrrh, Neroli, Rose, Grapefruit, Mandarin, Orange, and Roman Chamomile. The subjects of this experiment were postpartum mothers who delivered vaginally with an episiotomy. They were allocated to one of three groups; the aroma-sitz bath group, aroma-soap application group or control group. To evaluate the effect of aromatherapy, the perineal healing status was measured using the REEDA scale and smears of episiotomy wound were obtained. The data were analyzed by repeated measures of ANOVA, ANCOV A, x$^2$- test, and multiple response analysis via SPSS program. Results The REEDA scale was significantly low in the experimental group at postpartum 5th and 7th days (P=.009, P=.003), respectively. Most were observed ‘few’(5-10 bacteria per field) bacteria in the smears of episiotomy wound. The one bacteria was identified in the 50.8% of subjects in pretest and two bacteria in the 60.3% in posttest. Most frequently identified bacteria were Escherichia coli and Enterococcus faecalis. Conclusion In conclusion, these findings indicate that postpartum aromatherapy for perineal care could be effective in healing the perineum perineal care could be effective in healing the perineum.

A Review of the Effect of Korean Medicine on Genital Herpes (항문생식기 헤르페스에 대한 한의학적 치료의 국내외 연구동향 분석)

  • Pak, Yeon-Kyoung;Park, Chi-Young
    • The Journal of Korean Obstetrics and Gynecology
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    • v.31 no.1
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    • pp.99-121
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    • 2018
  • Objectives: Genital herpes is common disease in gynecological field. Although various treatment options such as herbal medicine, acupuncture, moxibustion are used in genital herpes, there is not enough evidence about the treatment options. This study is to prove the efficacy of oriental medicine on genital herpes by investigating papers and suggest direction of future research. Method: We searched for papers which had both genital herpes and oriental medicine from Cochrane, Pubmed, Scopus, CNKI, Oasis, Korean traditional knowledge portal, Journal of Korean Obstetrics & Gynecology up to November 2017. After searching papers, we classified according to the study design and analyzed selected studies. Results: Sixteen papers were finally selected. Four papers are laboratory studies with Hartley guinea pig with recurrent genital herpes. Twelve papers are clinical trials which includes one single group trial, one controlled trial, ten randomized controlled trials. All of the studies have shown that herbal medicine is effective in improving the symptom of genital herpes and decreasing the recurrent rate of genital herpes and also has immunoregulatory effect. Conclusions: This study shows that herbal medicine could be a good treatment option for genital herpes. However, more well-designed clinical studies and laboratory studies will be needed.

CFD validation and grid sensitivity studies of full scale ship self propulsion

  • Jasak, Hrvoje;Vukcevic, Vuko;Gatin, Inno;Lalovic, Igor
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.11 no.1
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    • pp.33-43
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    • 2019
  • A comparison between sea trial measurements and full-scale CFD results is presented for two self-propelled ships. Two ships considered in the present study are: a general cargo carrier at Froude number $F_n=0:182$ and a car carrier at $F_n=0:254$. For the general cargo carrier, the propeller rotation rate is fixed and the achieved speed and trim are compared to sea trials, while for the car carrier, the propeller rotation rate is adjusted to achieve the 80% MCR. In addition, three grids are used for each ship in order to assess the grid refinement sensitivity. All simulations are performed using the Naval Hydro pack based on foam-extend, a community driven fork of the OpenFOAM software. The results demonstrate the possibility of using high-fidelity numerical methods to directly calculate ship scale flow characteristics, including the effects of free surface, non-linearity, turbulence and the interaction between propeller, hull and the flow field.

Usage of Korean Herbal Medicine for Climacteric Symptoms - Analysis of Korean Clinical Studies (갱년기 증상에 대한 한약 사용 - 국내 한의 임상연구 분석)

  • Minjung Bae;Jaewoon Ha;Youngju Yun
    • Journal of Society of Preventive Korean Medicine
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    • v.27 no.2
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    • pp.85-107
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    • 2023
  • Objective : To investigate the usage of Korean herbal medicine (KHM) for climacteric symptoms, this study reviewed clinical studies conducted in Korea. Method : Literature search was performed on three Korean database; OASIS, RISS and NDSL. Studies published before July 2023 were categorized and analyzed according to the study type and herbal prescriptions. Results : Fifty-eight studies including 7 controlled trial, 27 case series and 24 single case reports were included in our review and the total number of case patients was 420. 52 prescriptions based on syndrome identifications and 11 prescriptions of Sasang constitutions were used and the most frequently used prescriptions were Soyosan(逍遙散) and Guibitang(歸脾湯). Thirty-two prescriptions were also mentioned in previous delphi research or clinical practice guideline, and the rest were not. Thirty-five studies used acupuncture combined with KHM and 10 studies used pharmacopuncture and 5 studies used herbal hipbath. Conclusion : To increase the therapeutic effect of KHM and establish KHM as an alternative to hormone treatment, various prescriptions should be used according to syndrome identifications in the clinical field. High-quality RCTs on frequently used prescriptions and the development of various type of KHM are also necessary.

Establishing Rationale for the Clinical Development of Cell Therapy Products: Consensus between Risk and Benefit

  • Seunghoon Han;Hyeon Woo Yim;Hyunsuk Jeong;Suein Choi;Sungpil Han
    • International Journal of Stem Cells
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    • v.16 no.1
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    • pp.16-26
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    • 2023
  • Despite long-term research achievements, the development of cell therapy (CT) products remains challenging. This is because the risks experienced by the subject and therapeutic effects in the clinical trial stage are unclear due to the various uncertainties of CT when administered to humans. Nevertheless, as autologous cell products for systemic administration have recently been approved for marketing, CT product development is accelerating, particularly in the field of unmet medical needs. The human experience of CT remains insufficient compared with other classes of pharmaceuticals, while there are countless products for clinical development. Therefore, for many sponsors, understanding the rationale of human application of an investigational product based on the consensus and improving the ability to apply it appropriately for CT are necessary. Thus, defining the level of evidence for safety and efficacy fundamentally required for initiating the clinical development and preparing it using a reliable method for CT. Furthermore, the expertise should be strengthened in the design of the first-in-human trial, such as the starting dose and dose-escalation plan, based on a sufficiently acceptable rationale. Cultivating development professionals with these skills will increase the opportunity for more candidates to enter the clinical development phase.

A Role of Trial Radiation Therapy in the Pineal Region Tumors (송과체부 종양에서 시험적 방사선치료의 역할)

  • Kim, Yeon-Shil;Ryu, Mi-Ryung;Chung, Su-Mi;Kim, Moon-Chan;Yoon, Sei-Chul
    • Radiation Oncology Journal
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    • v.20 no.2
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    • pp.100-107
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    • 2002
  • Purpose : The aim of this retrospective study was to assess the treatment results of 30 patients with pineal region tumors who were underwent radiation therapy under the diagnosis by either CT or MRI. There was no histological verification. We analyzed the prognostic factors that have a significant effect on the overall survival (OS) and disease free survival (DFS) rates. Materials and Methods : A total 30 patients with pineal region tumors were treated between March 1983 and August 1995. After a trial radiation therapy of $20\~30\;Gy/2\~3$ weeks, the patients were evaluated for their clinical response and radiological response by either CT or MRI and the final treatment direction was then decided. According to their response to the trial radiation therapy and the involved site, radiation treatment was given in various fields i.e., local, ventricle, whole brain and craniospinal field. The radiation dose ranged from 40.8 to 59.4 Gy (Median 50.4 Gy). The median follow up was 36.5 months $(4\~172\;months)$. Results : An improvement or stability in the clinical symptoms was observed in 28 patients $(93.3\%)$ after the trial RT. Nineteen patients $(63.3\%)$ showed a partial or complete response by CT or MRI. The two-year and five-year survival rates of the patients were $66.7\%$ and $55.1\%$, respectively. No significant difference in the survival rates according to the degree of the radiological response was abserved after the trial RT. The results of univariate analysis showed that age, the primary site, the performance status $(KPS\geq70)$, the degree of response after completing RT and the RT field were significant prognostic factors affecting the survival and disease free survival rates (p<0.05). Conclusion : The clinical and histological characteristics of pineal region tumors are quite complex and diverse. Therefore, it is difficult to predict the histological diagnosis and the possibility of radiocurability only with the initial response to RT. We think that the development of less invasive histological diagnostic techniques and tailored treatment to the histological type of each tumor are needed.

Quantitative Analysis of a Steel Billet Surface Flaw Detection System by Means of a Finite Element Method

  • Bae, Sungwoo;Lee, Hongyeob
    • Journal of Electrical Engineering and Technology
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    • v.11 no.6
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    • pp.1729-1734
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    • 2016
  • The surface inspection of a steel billet is a common practice in the steel manufacturing process prior to hot rolling to produce steel wire for tire cord. This billet surface inspection is an important process because flaws on the surface may cause major failures during the product manufacturing phase. This paper presents a computer simulation based on a finite element method for a magnetic flaw detector with a function of the current intensity, the number of coil turns, and the billet proceeding speed during the production phase based on the typical condition of conventional apparatus. Based on the simulation result, the magnitude of the electromagnetic field on the surface diminished with distance from the electromagnet. In addition, the increased current intensity and the increased number of coil turns actually induced a stronger electromagnetic field on the billet surface. On the other hand, the proceeding speed of a billet in its production line had no significant effects. The result in this study may assist to reduce trial and error and to minimize the opportunity costs during the optimization process by applying the findings of this study into the operation condition in the steel billet production line.

Analysis on Ratio and Proportion Concepts: A Story of a Fourth Grader (4학년 아동의 비와 비례 개념 분석)

  • Lee Jong-Euk
    • Journal of Educational Research in Mathematics
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    • v.16 no.2
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    • pp.157-177
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    • 2006
  • The concepts of ratio and proportion do not develop in isolation. Rather, they are part of the individual's multiplicative conceptual field, which includes other concepts such as multiplication, division, and rational numbers. The current study attempted to clarify the beginning of this development process. One fourth student, Kyungsu, was encourage to schematize his trial-and-error-based method, which was effective in solving so-called missing-value tasks. This study describes several advancements Kyungsu made during the teaching experiment and analyzes the challenges Kyungsu faced in attempting to schematize his method. Finally, the mathematical knowledge Kyungsu needed to further develop his ratio and proportion concepts is identified. The findings provide additional support for the view that the development of ratio and proportion concepts is embedded within the development of the multiplicative conceptual field.

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Advanced Field Weakening Control for Maximum Output Power Operation of Seawater Cooling Pump Induction Motor in a Limited Environment (제한된 환경에서의 해수냉각펌프용 유도전동기 최대출력 운전을 위한 약계자 제어)

  • Son, Yung-Deug;Seo, Yong-Joo;Jung, Jun-Hyung;Kim, Jang-Mok
    • The Transactions of the Korean Institute of Power Electronics
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    • v.18 no.6
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    • pp.540-546
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    • 2013
  • The induction motor is used for driving the special equipments such as warship and submarine pump due to robust structure and simple maintenance. Domestic and foreign warships use a wide range of voltages and the DC voltage sources mainly from battery. In the low voltage level, the ${\Delta}$-connection operation of induction motor can be used for the maximum power. However, the temperature of the inverter increases because of the high input current. On the other hand, Y-connection operation of the induction motor does not cause a problem of temperature because of the low input current compared to the ${\Delta}$-connection. But the lack of the supply voltage can not be avoided. Therefore, this paper suggests the algorithm of the optimum field weakening control to extend the operating range of the induction motor with maximum power in a limited thermal and DC voltage condition.