• Title/Summary/Keyword: Reduction methods

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Development of an Oxide Reduction Process for the Treatment of PWR Spent Fuel (PWR 사용후핵연료 처리를 위한 금속전환공정 개발)

  • Hur, Jin-Mok;Hong, Sun-Seok;Jeong, Sang-Mun;Lee, Han-Soo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.1
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    • pp.77-84
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    • 2010
  • Reduction of oxides has been investigated for the volume reduction and recycling of the spent oxide fuel from commercial nuclear power plants. Various oxide reduction methods were proposed and KAERI (Korea Atomic Energy Research Institute) is currently developing an electrochemical reduction process using a LiCl-$Li_2O$ molten salt as a reaction medium. The electrochemical reduction process, the front end of the pyroprocessing, can connect the PWR (Pressurized Water Reactor) oxide fuel cycle to a metal fuel cycle of the sodium cooled fast reactor. This paper summarizes KAERI efforts on the development, improvement, and scale-up of the oxide reduction process.

Sodium content changes between 2015 and 2019 in restaurant menu items selected for sodium reduction in Daegu

  • Ma, Jian;Lee, Yeon-Kyung
    • Nutrition Research and Practice
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    • v.16 no.4
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    • pp.537-548
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    • 2022
  • BACKGROUND/OBJECTIVES: South Korea has been conducting the Sodium Reduction Restaurant Project since 2015 to reduce sodium contents in restaurant menus. The purpose of this study was to analyze changes in the sodium content of menus as determined by the Daegu Sodium Reduction Restaurant Project between 2015 and 2019. MATERIALS/METHODS: Intervention was aimed at reducing the sodium contents of over 10% of menu items in participating restaurants. On-site inspections and evaluations were conducted using a checklist, and reductions in sodium contents were determined by analyzing the salinities and sodium contents of menus after intervention. RESULTS: Post-intervention salinities and sodium contents were significantly lower than baseline values in 2016 (P < 0.001), 2017 (P < 0.001), 2018 (P < 0.001), and 2019 (P < 0.001). However, sodium contents and salinities differences before and after intervention were not significant in 2015. Sodium contents of more than 20% of menu items offered by restaurants that participated in the Sodium Reduction Restaurant Project for 2 yrs starting in 2016 declined by 28.9%. On the other hand, the sodium reduction rate achieved by restaurants that participated for 4 yrs from 2015 reached 55.4%. The percentage of restaurants that participated in the project increased annually, though some failed to be designated as Sodium Reduction Restaurants because they did not meet sodium reduction rate requirements. CONCLUSIONS: Positive correlations were found between duration of participation in the project and sodium reduction and designation rates. Sustainable long-term support at the national level is required to expand the project to other regions.

Experimental Study of Dadun(LR1)·Shaofu(HT8) Reduction in Acupuncture on the Improvement of Cerebral Hemodynamics (대돈(大敦)·소부(少府) 사법자침(瀉法刺鍼)이 뇌혈류역학(腦血流力學) 변동(變動) 개선(改善)에 미치는 영향)

  • Shin, Dong-hoon;Cho, Myoung-rae
    • Journal of Acupuncture Research
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    • v.21 no.1
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    • pp.33-50
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    • 2004
  • Objective: The aim of this study was to investigate anti-ischemic effect of LR1 HT8 Reduction in Acupuncture Methods: I designed to investigate whether LR1 HT8 Reduction in Acupuncture affects cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD), mean arterial blood pressure(MABP)] in normal rats and to make manifest whether LR1 HT8 Reduction in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. The changes of rCBF and MABP were determinated by laser-doppler flowmetry(LDF), and the change of PAD was de terminated by video microscope and width analyzer. Results: The results were as follows; 1. LR1 Reduction in Acupuncture was increased rCBF and PAD, but decreased MABP. 2. HT8 Reduction in Acupuncture was significantly increased rCBF, but decreased MABP, and increased PAD. 3. LR1 HT8 Reduction in Acupuncture was significantly increased rCBF, PAD, but decreased MABP after withdrawing of the needle. This results suggest that LR1 HT8 Reduction in Acupuncture increased significantly rCBF by dilating PAD. 4. Pretreatment with indomethacin(1mg/kg, i,v.) was significantly inhibited LR1 HT8 Reduction in Acupuncture induced increase of rCBF and PAD, but increased LR1 HT8 Reduction in Acupuncture induced decrease of MABP after withdrawing of the needle. 5. Pretreatment with methylene blue($10{\mu}g/kg$, i,v.) was decreased LR1 HT8 Reduction in Acupuncture induced increase of rCBF and PAD, but accelerated LR1 HT8 Reduction in Acupuncture induced decrease of MABP. Conclusions: I suggest that LR1 HT8 Reduction in Acupuncture has an anti-ischemic effect through the improvement of cerebral hemodynamics, and the mechanism is mediated by cyclooxygenase.

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A REVIEW ON REDUCTION IN FINITE ELEMENT ANALYSIS

  • Kim, Ki-Ook;Park, Young-Jae
    • Journal of Theoretical and Applied Mechanics
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    • v.3 no.1
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    • pp.1-15
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    • 2002
  • Reduction methods for large structural systems have been reviewed. Mai emphasis is put on the dynamic reduction. Recently, the computing resources and technologies have been expanded so fast that the huge matrices Invoked In the analysis of structural system can be processed without serious difficulties. For most users, however, the computer facilities are limited and the system reductions in some forms are required. The reduction procedure in static problems is simple and straightforward. The major task is the book-keeping in computations. In dynamic problems and structural optimization. however. the problem is much more complicated. The problem is, in general, nonlinear and hence the exact solution is not available. Therefore, approximate solutions are sought in an iterative manner. A proper convergence criterion needs to be employed in order to get an accurate solution efficiently. Several research works have been reported fer the structural optimization combined with system reductions.

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Adaptive Noise Reduction Algorithm for an Image Based on a Bayesian Method

  • Kim, Yeong-Hwa;Nam, Ji-Ho
    • Communications for Statistical Applications and Methods
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    • v.19 no.4
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    • pp.619-628
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    • 2012
  • Noise reduction is an important issue in the field of image processing because image noise lowers the quality of the original pure image. The basic difficulty is that the noise and the signal are not easily distinguished. Simple smoothing is the most basic and important procedure to effectively remove the noise; however, the weakness is that the feature area is simultaneously blurred. In this research, we use ways to measure the degree of noise with respect to the degree of image features and propose a Bayesian noise reduction method based on MAP (maximum a posteriori). Simulation results show that the proposed adaptive noise reduction algorithm using Bayesian MAP provides good performance regardless of the level of noise variance.

Effectiveness of Mini-Implant for the Reduction of Mandibular Fracture

  • Kim, Nam-Ho;Heo, Jeong-Uk;Park, Jun-Sub
    • Journal of Korean Dental Science
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    • v.6 no.1
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    • pp.4-12
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    • 2013
  • Purpose: This study sought to verify the usefulness of mini-implant and surgical steel wire in the treatment of mandibular fracture through the objective identifi cation of the change of bone structure and bone density before and after reduction by evaluating radiological change through fractal analysis when mandibular fracture is treated using mini-implant and surgical wire. Materials and Methods: This study looked at 45 patients (males: 38, female: 7) diagnosed with mandibular fracture in the oral and maxillofacial surgery division of Chung-Ang University Dental Hospital and who received open reduction and intra-osseous fi xation. Result: The average fracture dimension values were higher for the group of the patients who had mini-implants and surgical wire treatment. Conclusion: Based on the results of the study on the usefulness of the reduction technique using mini-implant and surgical steel wire in the treatment of mandibular fracture through the fractal analysis method, the reduction technique using mini-implant and surgical steel wire is regarded as an effective method of minimizing the gap between mandibular fracture fragments.

Factors Affecting the Cost-Reduction Practice of Clinical Nurses (임상 간호사의 비용절감수행 영향 요인)

  • Park, Grum-Ja;Lim, Kyoung-Min
    • The Korean Journal of Health Service Management
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    • v.10 no.2
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    • pp.49-58
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    • 2016
  • Objectives : The purpose of this study was to find factors affecting the cost-reduction practice of clinical nurses. Methods : The Data were collected from Feb. 25, to Mar. 15, 2015.the Total subjects were 201 nurses working in secondary-care hospitals located in Busan Results : The Meaningful variables that explain the cost-reduction practice in clinical nurses were psychological ownership, religion, and marital status in that order. Total explanation power was 22.1.% and psychological ownership has most explanation power. Conclusions : Psychological ownership and economic consciousness need to improve to develop cost-reduction practices. Additionally, nurses with and low concern about finances need to receive financial-related education.

Improved Model Reduction Algorithm by Nyquist Curve (Nyquist 선도에 의한 개선된 모델 축소 알고리즘)

  • Cho, Joon-Ho;Choi, Jung-Nae;Hwang, Hyung-Soo
    • Proceedings of the KIEE Conference
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    • 2001.11c
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    • pp.215-218
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    • 2001
  • To improve the performance of PID controller of high order systems by model reduction, we proposed a new model reduction method in frequency domain. A new model reduction method we proposed, considered four points (${\angle}G(jw)=0$, $-{\pi}/2$, $-{\pi}$, $-3{\pi}/2$) in stead of two points (${\angle}G(jw)=-{\pi}/2$, and $-{\pi}$) in Nyquist curve. And for high order systems that it have not two point (${\angle}G(jw)=-{\pi}/2$, and $-{\pi}$) in Nyquist curve, we proposed a method to annex very small dead time. This method has a annexed very small dead time on the base model for reduction, and we cancel it after to get the reduced model. It is shown that the performance of proposed method is better than any other methods.

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Stable PID Tuning for High-order Integrating Processes using Model Reduction Method (모델축소를 이용한 고차계 적분공정의 안정한 PID 동조)

  • Lee, Won-Hyok;Hwang, Hyung-Soo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.11
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    • pp.2010-2016
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    • 2007
  • PID control is windely used to control stable processes, However, its application to integrating processes is less common. In this paper, we proposed a stable PID controller tuning method for integrating processes with time delay using model reduction method. For proposed model reduction method, it disconnect an integrating factor from integrating processes and reduces separate process using reduction method. and it connect an integrating factor to reduced model. We can obtain stable integrating processes using P controller in inner feedback loop and PID tuning is then used to cancel the pole of the feedback loop. This guarantees both robustness and performance. Simulation examples are given to show the good performance of the proposed tuning method comparing with other methods.

Changes in the Texture and Salt Content of Chinese Cabbage Using Different Salting Methods (절임 방법에 따른 배추 조직 및 염도 변화)

  • Lee, Myung-Ki;Yang, Hye-Jung;Woo, Ha-Na;Rhee, Young-Kyoung;Moon, Sung-Won
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.8
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    • pp.1184-1188
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    • 2011
  • This study analyzed changes in the texture and salt content of Chinese cabbage after salting using different methods to determine the effects of low salt brining. To verify the possibility of brining under low salt concentration, Chinese cabbage was salted with 1%, 2%, 6%, and 10% salt solutions by pressing, pressure reduction, or steaming. After salting, the firmness (g, determined using the puncture test) of the Chinese cabbage changed according to the brining methods used, however, an increasing trend in rigidity was observed as the salinity increased. Because the power applied during pressing or pressure reduction treatments is higher, the firmness of and penetration time on the surface of the brined Chinese cabbages after these treatments increased more in the 6% salt solution cabbage. Additionally, the Chinese cabbages treated with steam showed significantly higher firmness and penetration time than those treated by pressing and pressure reduction. As a result of pressing the 6% salt concentrated cabbage with 1.35 $kg{\cdot}f/cm^2$, a pressure reduction from 250 mmHg, and steaming at 100$^{\circ}C$ for 1 min, the cabbage had roughly 2% of the salt concentration, ultimately. These physical treatments of pressing, pressure reduction, and steaming could be used as new methods for preparing salted Chinese cabbage with low salt concentrations for general use.