• Title/Summary/Keyword: Short circulation

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Dynamic analysis of short circulation with OPR prediction used neural network (Neural network을 이용한 OPR예측과 short circulation 동특성 분석)

  • Jeon, Jun-Seok;Yeo, Yeong-Gu;Park, Si-Han;Gang, Hong
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2004.04a
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    • pp.86-96
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    • 2004
  • Identification of dynamics of short circulation during grade change operations in paper mills is very important for the effective plant operation. In the present study a prediction method of One Pass Retention(OPR) is proposed based on the neural network. The present method is used to analyze the dynamics of short circulation during grade change. Properties of the product paper largely depend upon the change in the OPR. In the present study the OPR is predicted from the training of the network by using grade change operation data. The results of the prediction are applied to the modeling equation to give flow rates and consistencies of short circulation.

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Modeling of Short Circulation in Paper Mills (제지공장의 Short Circulation 공정의 모델링)

  • Jeon, Jun-Seok;Yeo, Yeong-Gu;Kim, Yeong-Gon;Gang, Hong
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2003.11a
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    • pp.217-229
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    • 2003
  • Analysis of the elements affecting short circulation in highly integrated paper mills and identification of the interactions among these elements are very important tasks to prevent operational perturbations such as web breaks. In the present work a dynamic model for the short circulation is developed to analyze tuning methods for the outputs to follow set points during grade change operations. Steady state operation data are used to investigate dynamic characteristics of responses for input changes.

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Analysis of Dynamics of Short Circulation in Paper Mills (제지공정 Short Circulation의 동특성 해석)

  • Jeon, Jun-Seok;Yeo, Young-Gu;Kim, Young-Gon;Kang, Hong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.35 no.4
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    • pp.42-47
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    • 2003
  • Analysis of the elements affecting short circulation in highly integrated paper mills and identification of the interactions among these elements are very important tasks to prevent operational perturbations such as web breaks. In the present work a dynamic model for the short circulation is developed to analyze tuning methods for the outputs to follow set points during grade change operations. Steady state operation data are used to investigate dynamic characteristics of responses for input changes.

Return of spontaneous circulation rate according to dispatch distance in out-of-hospital cardiac arrest (출동 거리에 따른 병원 전 심장정지 환자의 자발순환회복률 분석)

  • Kim, Jong-Ho;Jeon, Youn-Chel;Moon, Jun-Dong
    • The Korean Journal of Emergency Medical Services
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    • v.21 no.2
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    • pp.51-61
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    • 2017
  • Purpose: This study measured return of spontaneous circulation (ROSC) in relation to dispatch distance in patients with out-of-hospital cardiac arrest. Methods: Of 2,347 out-of-hospital cardiac arrest patients transported by emergency medical technicians in J Province between January 1 and December 31, 2015, those under age 18, those with reserved resuscitation, and those with traumatic cardiac arrest, leaving 855 patients in the study sample. ROSC was compared between those with dispatch distance ${\leq}4km$ (short dispatch distance, 465 patients) and those with dispatch distance >4 km (long dispatch distance, 390 patients). Results: The mean was 2.17 km in the short dispatch group and 9.87 km in the long dispatch group (p=.000). Mean distance from was 6.49 km and 13.39 km in the two groups, respectively (p=.000). ROSC differed significantly between the short and long dispatch distance groups (7.1% for short dispatch distance, 3.6% for long dispatch distance, p=.025). The length of time from to cardiopulmonary resuscitation also differed significantly between the short and long dispatch distance groups (8.77 minutes and 14.63 minutes, respectively, p=.000). Conclusion: ROSC was lower in areas of long dispatch distance compared to those of short dispatch distance. We expect this was most likely due to differences in response time by age and dispatch distance to the scene of cardiac arrest. However, no significant differences were found between the groups in the factors affecting ROSC.

Climate Change and the Thermohaline Circulation of the Oceans (기후 변환와 해양 열염분 순환)

  • Park, Young-Gyu
    • Atmosphere
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    • v.15 no.1
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    • pp.69-74
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    • 2005
  • In this short article, oceanic processes that could have strong effect on the climate have been explained while focusing on the oceanic thermohaline circulation (THC). First, the structure of THC is explained using a simple scaling law. Then, the thermohaline catastrophe, which is believed to be a cause of a rapid climate changes observed in paleoclimate records, and interdecadal variations in THC are explained. The interactions between the oceans and $CO_2$ are also mentioned briefly.

A Study on the Effects of Auction-Based Short Distance Division Logistics Operation on Logistics Costs (경매를 활용한 근거리 분할 물류운영이 물류비용에 미치는 영향에 관한 연구)

  • Kim, Byeongchan
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.12 no.3
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    • pp.299-309
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    • 2016
  • This study proposed a logistics plan for sending supply to be distributed to areas other than producing areas to wholesalers and allocating supply to be distributed to areas near producing areas to local distribution center in the vicinity instead of shipping the entire quantity to wholesalers for fruits auction to increase the competitive edge of the domestic fruits and vegetables logistics market in the ear of infinite competition. A video auction-based short distance division logistics operation model was developed to enhance competitiveness related to the circulation of fruits and vegetables, reduce logistics costs, and rationalize logistics by distributing the items sent to wholesalers through field auction and the shipments at local distribution center to neighboring areas through video auction connected to wholesalers real-time. The study especially came up with a logistics rationalization plan by examining and analyzing the stages and costs of transportation between producing areas and wholesalers on the circulation routes of fruits.

The Effect of Functional Shoes (Coolfin) on Top of Foot and Great Toe Blood Circulation (기능성 신발 쿨핀(Coolfin) 착용이 발등 및 엄지발가락 혈액순환에 미치는 영향)

  • Kim, Yun-Jin;Lee, Dong-Ryul;Sang, Hie-Sun;Lee, Mi-Nam;Park, Ji-Won
    • The Journal of Korean Physical Therapy
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    • v.26 no.4
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    • pp.220-225
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    • 2014
  • Purpose: This study aims to investigate the impact of a short walk putting on Coolfin shoes on the foot temperature rise and blood circulation. Methods: Twenty healthy adults participated in experiments in this study. All subjects walked respectively barefoot and putting on Coolfin shoes. Infrared imaging cameras were used to collect and analyze the data on the foot temperature. Results: As a result of this study, there were significant differences between the temperatures of the great toe and top of the foot after 20-minute walks with bare feet and in Coolfin shoes. Both the temperatures of the great toe and top of the foot decreased after a 20-minute walk in the barefoot condition, and there was a significant difference between them (p<0.05). Both the temperatures of the great toe and top of the foot increased after a 20-minute walk in the condition of putting on Coolfin shoes, and there was a significant difference between them(p<0.05). Conclusion: A short walk putting on Coolfin products induces the movement of the toes to increase the blood flow and accordingly, has a direct impact on the increase of the surface temperature of the feet, so they are effective products for helping blood circulation in the feet.

Membrane distillation of power plant cooling tower blowdown water

  • Ince, Elif;Uslu, Yasin Abdullah
    • Membrane and Water Treatment
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    • v.10 no.5
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    • pp.321-330
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    • 2019
  • The objective of this study was to examine the recovery of the power plant cooling tower blowdown water (CTBD) by membrane distillation. The experiments were carried out using a flat plate poly vinylidene fluoride (PVDF) membrane with a pore diameter of $0.22{\mu}m$ by a direct contact membrane distillation unit (DCMD). The effects of operating parameters such as transmembrane temperature difference (${\Delta}T$), circulation rate and operating time on permeate flux and membrane fouling have been investigated. The results indicated that permeate flux increased with increasing ${\Delta}T$ and circulation rate. Whereas maximum permeate flux was determined as $47.4L/m^2{\cdot}h$ at ${\Delta}T$ of $50^{\circ}C$ for all short term experiments, minimum permeate flux was determined as $7.7L/m^2{\cdot}h$ at ${\Delta}T$ of $20^{\circ}C$. While $40^{\circ}C$ was determined as the optimum ${\Delta}T$ in long term experiments. Inorganic and non-volatile substances caused fouling in the membranes.

Characteristics Analysis of Short Flux Path Switched Reluctance Motor

  • Ahn, Jin-Woo
    • Journal of international Conference on Electrical Machines and Systems
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    • v.1 no.2
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    • pp.38-45
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    • 2012
  • A novel kind of switched reluctance motor (SRM) with short flux path is proposed in this paper. Phase excitation in the SRM gives short flux paths, hence reducing the magnetomotive force required to drive the machine, resulting in significant reduction of copper wire and core losses compared to the typical SRM with diametric circulation of magnetic flux. To verify the performance, the characteristics analysis of a double-stator SRM, a 6/5 SRM with C-core structure, and a 4/5 two-phase SRM, which all have short flux paths, and a comparison with conventional SR motors are executed. The comparison demonstrates that the proposed motor offers some advantages in terms of torque and efficiency.

대전지역 약수의 수질특성과 관리방안

  • 정찬호;김은지;문병진
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.09a
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    • pp.15-18
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    • 2001
  • Sixty natural springs and wells used as community facilities for drinking water are developed along mountain climbing way of suburban area and residential area in Daejeon City. In this study, the seasonal variation of their water quality and hydrochemical characteristics were investigated. Some natural springs are vulnerable to bacilli contamination because of their short residence time and shallow circulation in subsurface environment. The waters show hydrochemical types of Ca-HCO$_3$ and Na-HCO$_3$, and are characterized by low electrical conductance and weak acidic pH.

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