• Title/Summary/Keyword: flow control

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Development and Application of Siphon Breaker Simulation Program (사이펀 차단기 시뮬레이션 프로그램의 개발 및 활용)

  • Lee, Kwon-Yeong;Kim, Wan-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.346-353
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    • 2016
  • In the design conditions of some research reactors, the siphon phenomenon can cause continuous efflux of water during pipe rupture. A siphon breaker is a safety device that can prevent water efflux effectively. However, the analysis of the siphon breaking is complicated because many variables must be included in the calculation process. For this reason, a simulation program was developed with a user-friendly GUI to analyze the siphon breaking easily. The program was developed by MFC programming using Visual Studio 2012 in Windows 8. After saving the input parameters from a user, the program proceeds with three steps of calculation using fluid mechanics formulas. Bernoulli's equation is used to calculate the velocity, quantity, water level, undershooting, pressure, loss coefficient, and factors related to the two-phase flow. The Chisholm model is used to predict the results from a real-scale experiment. The simulation results are shown in a graph, through which a user can examine the total breaking situation. It is also possible to save all of the resulting data. The program allows a user to easily confirm the status of the siphon breaking and would be helpful in the design of siphon breakers.

An Integrated QoS Management System for Large-Scale Heterogeneous IP Networks : Design and Prototype Implementation (대규모 이기종 IP 망의 통합품질관리 시스템의 설계 및 구현)

  • Choi, Tae-Sang;Chung, Hyung-Seok;Choi, Hee-Sook;Kim, Chang-Hoon;Jeong, Tae-Soo
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.11S
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    • pp.3633-3650
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    • 2000
  • Internet is no longer a network for special communities but became a global means of communication infrastructure for everyday life. People are exchanging their personal messages using e-mails, students are getting their educational aids through the web, people are buying a variety of goods from cyber shopping malls, and companies are conducting their businesses over the Internet. Recently, such an explosive growth of the traffic in the Internet raised a big concern on how to accommodate ever-changing user's needs in terms of an amount of the traffic, characteristics of the traffic, and various service quality requirements, Over provisioning can be a simple solution but it is too expensive and inefficient. Thus many new technologies to solve this very difficult puzzle have bcen introduced recently, Any single solution, however, can be insufficient and a carefully designed architecture, which integrates a group of solutions, is required. In this paper, we propose a policy-based Internet QoS provisioning, traffic engineering and perfonnance management system as our solution to this problem. Our integrated management QoS solution can provide highly responsive flow-through service provisioning, more realistic service and resource policy control based on the real network performance information, and centralized control of traffic engineering for heterogeneous networks.

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A Study on the Development of Non-PC High-Early-Strength Concrete Without Steam Curing (증기양생이 불필요한 PC부재용 조강형 콘크리트 개발에 관한 연구)

  • Jun, Woo-Chul;Lee, Ji-Hwan;Park, Hee-Gon;Lee, Jae-Sam;Kim, Kyung-Min;Cho, In-Sung
    • Journal of the Korea Institute of Building Construction
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    • v.14 no.2
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    • pp.156-162
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    • 2014
  • This study aims to develop a rapidly hardening type of concrete to achieve the removal of form intensity (more than 10MPa) using the method of curing at room temperature in order to solve some economic environmental problems by omitting the steam curing process involved in producing PC (Precast Concrete). Therefore, this study evaluated a rapidly hardening cement containing a high amunt of C3S, which is very responsive in expressing early intensity, and a rapidly hardening type of concrete which uses some hardening accelerator to increase thehydration reaction of $C_3S$. The results of the experiment on concrete using some hardening accelerator are asfollows. In the slump flow experiment for identifying the liquidity and the air test, the desired values were met. The compression strength showed rapid expression response by 12 hours, and met the desired value within 6~9 hours. Its drying shrinkage value and Autogenous shrinkage value were measured as below ($-754.5{\times}10^{-6}$),and satisfied the requirements. In addition, in the Semi-Adiabatic Temperature Test, it was found that the concrete rose to its peak temperature within 24 hours and then its temperature dropped.

Supplement of Conjugated Linoleic Acid Increases Neutrophil Phagocytosis in Pigs (Conjugated Linoleic Acid를 급여한 돼지의 호중구 탐식능 증강)

  • Sang-chul, Han;Ji-houn, Kang;Sung-mok, Son;Chung-soo, Chung;Chul-young, Lee;Mhan-pyo, Yang
    • Journal of Veterinary Clinics
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    • v.20 no.4
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    • pp.437-442
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    • 2003
  • To examine the in vivo immunostimulating effect of conjugated linoleic acid (CLA) in pigs, the change of peripheral blood cells and the phagocytic response of phagocytes were evaluated. Spayed male pigs, 80 kg of average body weight, fed a diet containing either 0.5% 10t-12c CLA or 0.5% CLA mixture (mostly 9c-11t CLA and 10t-12c CLA) for 4 weeks. The change of blood cell values (PCV, WBC, differential count of WBC) and the phagocytic activities of phagocytes were evaluated on week 0, 2, 4, and 5, respectively. There were no change in the PCV values regardless of CLA supplement. The number of WBC, especially neutrophils, in pigs fed a diet with CLA was significantly increased (p<0.05 to 0.01) when compared with control pigs fed a diet without CLA. The phagocytosis of peripheral blood mononuclear cell (MNC) and peripheral blood polymorphonuclear cells (PMN) were analyzed by a flow cytometry system. There was no change in the phagocytic activity of MNC and monocyte-rich cells regardless of CLA supplement. However, the phagocytic activity of PMN composed by approximately 95% neutrophils was remarkably increased (p < 0.05 to 0.01) on week 2, 4, and 5 as compared wth control pigs. These results suggested that supplement of CLA into pigs induces the increase of neutrophil number and the enhancement of neutrophil phagocytosis.

The Effects of Duchesnea india(Audra.) Foche. on Human Stomach Cancer Cells (사매가 위암세포에 미치는 영향)

  • Ryu Bong-Ha;Kim Jin-Sung;Yoon Sang-Hyub;Ryu Ki-Won;Hong Sang-Sun
    • The Journal of Internal Korean Medicine
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    • v.24 no.2
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    • pp.290-299
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    • 2003
  • Background : Nowadays many researches about it s cure are going on world widely since cancer is one of the most human health threatening diseases. In Chinese and North Korean medicine, Duchesnea india(Audra.) Foche. is practically used to treat many kinds of cancer, but in Korea it is rarely used. So, we need to scientifically identify anti-tumor effects of Duchesnea india(Audra.) Foche. Objective : We are aimed to identify anti-tumor effects of Duchesnea india(Audra.) Foche. on the stomach cancer cells through molecular biologic methods. Material & Methods : We used AGS as stomach cancer cells from American Type Culture Collection. We added the boiled extract of Duchesnea india(Audra.) Foche. $5{\mu}l$(Sample I), $10{\mu}l$(Sample II) to cultural media(ml)for 0,6, 12, 24, 48 hours. We measured the killing effect on stomach cancer cells through Tryphan blue exclusion test and the suppressive effect on viability of stomach cancer cells via MTT assay. the quantitative RT-PCR was used to examine their effect on the revelation of Bcl-2, Bcl-XL, and Bax, which are genes related to apoptosis. We measured change of mitochondria membrane permeability and membrane potential via flow cytometry. Result : 1. The killing effect on stomach cancer cells showed that each test groups killed more stomach cancer cells than the control group with a time(6 hours later) and density dependent manner, which was statistical significance. 2. The suppressive effect on viability of stomach cancer cells showed that each test groups had more suppressive effects on viability of stomach cancer cells than the control group with a time(6 hours later), which was statistical significance. 3. In the test about the revelation of genes related to apoptosis, the revelation of Bcl-2 and Bcl-XL decreased with a density manner which was statistical significance. but the revelation of Bax was not changed with statistical significance. 4. As a result of this test, Duchesnea india(Audra.) Foche. caused apoptosis by decreasing the absorbance of mitochondria with statistical significance. and also induced apoptosis by decreasing the membrane potential of mitochondria. Conclusion : This experiment showed that Duchesnea india(Audra.) Foche. has anti-tumor effect with statistical significance. This is in vitro experiment and basic experiment on Duchesnea india(Audra.) Foche. We hope more progressive researchs on Duchesnea india(Audra.) Foche. will go on and its anti-tumor effects will be more practically identified.

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The Effect of Adding Kami-guibi-tang to Acetylcholinesterase Inhibitor Treatment on the Cognitive Function of Mild Alzheimer's Disease Patients: Study Protocol of a Randomized, Placebo-Controlled, Double-Blind Pilot Trial

  • Yang, Seung-bo;Kim, Ha-ri;Shin, Hee-yeon;Kim, Jeong-hwa;Lee, Chang-woo;Jahng, Geon-ho;Park, Seong-uk;Ko, Chang-nam;Park, Jung-mi
    • The Journal of Internal Korean Medicine
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    • v.41 no.3
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    • pp.326-338
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    • 2020
  • Background: Alzheimer's disease (AD) is a chronic neurodegenerative disease that causes disorientation, mood swings, problems with language, and difficulty remembering recent events. Acetylcholinesterase inhibitors (AchEIs) and memantine have been used to slow the course of the disease, but they can neither modify its progression nor prevent disease onset. Previous studies have suggested that Kami-guibi-tang (KGT) could be beneficial for supporting cognitive function in AD patients, but few clinical trials have been published. This pilot study aimed to evaluate the effect of KGT in improving cognitive function in AD patients. Methods: The study will be a randomized, placebo-controlled, double-blind, single-center trial conducted using subjects diagnosed with mild AD by neurologists. Study subjects will be randomly assigned to either a treatment or control group. The treatment group will receive KGT granules for 24 weeks, while the control group will receive placebo granules. AchEI administration will be maintained in both groups during the entirety of the study. Subjects will be assessed using the following exams: the Seoul Neuropsychologic Screening Battery (SNSB) for cognitive function; brain magnetic resonance imaging (MRI) for brain metabolite, neurotransmitter, and cerebral blood flow (CBF) measurements; the Korean version of Quality of Life-Alzheimer's Disease (KQol-AD) for quality of life; the Caregiver-Administered Neuropsychiatric Inventory (CGA-NPI) for neurobehavioral symptoms; blood tests for amyloid and tau proteins and general blood parameters; and electrocardiography (ECG) before and after taking the medication. Discussion: Our findings will provide insight into the feasibility of large-scale trials to consolidate evidence for the efficacy of KGT for dementia treatment. Registration ID in CRIS: KCT0002904 (Clinical Research Information Service of the Republic of Korea).

Anti-fibrotic effects of Orostachys japonicus A. Berger (Crassulaceae) on hepatic stellate cells and thioacetamide-induced fibrosis in rats

  • Koppula, Sushruta;Yum, Mun-Jeong;Kim, Jin-Seoub;Shin, Gwang-Mo;Chae, Yun-Jin;Yoon, Tony;Chun, Chi-Su;Lee, Jae-Dong;Song, MinDong
    • Nutrition Research and Practice
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    • v.11 no.6
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    • pp.470-478
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    • 2017
  • BACKGROUND/OBJECTIVE: Orostachys japonicus A. Berger (Crassulaceae) has been used in traditional herbal medicines in Korea and other Asian countries to treat various diseases, including liver disorders. In the present study, the anti-fibrotic effects of O. japonicus extract (OJE) in cellular and experimental hepatofibrotic rat models were investigated. MATERIALS/METHODS: An in vitro hepatic stellate cells (HSCs) system was used to estimate cell viability, cell cycle and apoptosis by MTT assay, flow cytometry, and Annexin V-FITC/PI staining techniques, respectively. In addition, thioacetamide (TAA)-induced liver fibrosis was established in Sprague Dawley rats. Briefly, animals were divided into five groups (n = 8): Control, TAA, OJE 10 (TAA with OJE 10 mg/kg), OJE 100 (TAA with OJE 100 mg/kg) and silymarin (TAA with Silymarin 50 mg/kg). Fibrosis was induced by treatment with TAA (200 mg/kg, i.p.) twice per week for 13 weeks, while OJE and silymarin were administered orally two times per week from week 7 to 13. The fibrotic related gene expression serum biomarkers glutathione and hydroxyproline were estimated by RT-PCR and spectrophotometry, respectively, using commercial kits. RESULTS: OJE (0.5 and 0.1 mg/ mL) and silymarin (0.05 mg/mL) treatment significantly (P < 0.01 and P < 0.001) induced apoptosis (16.95% and 27.48% for OJE and 25.87% for silymarin, respectively) in HSC-T6 cells when compared with the control group (9.09%). Further, rat primary HSCs showed changes in morphology in response to OJE 0.1 mg/mL treatment. In in vivo studies, OJE (10 and 100 mg/kg) treatment significantly ameliorated TAA-induced alterations in levels of serum biomarkers, fibrotic related gene expression, glutathione, and hydroxyproline (P < 0.05-P < 0.001) and rescued the histopathological changes. CONCLUSIONS: OJE can be developed as a potential agent for the treatment of hepatofibrosis.

A Study of Sewer Layout to Control a Outflow in Sewer Pipes (우수관거 흐름 제어를 위한 관망 설계에 관한 연구)

  • Kim, Joong-Hoon;Joo, Jin-Gul;Jun, Hwan-Don;Lee, Jung-Ho
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.1
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    • pp.1-7
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    • 2009
  • Most developed models are designed to determine pipe diameter, slope and overall layout in order to minimize the cost for the design rainfall for the optimal sewer layout. However, these models are not capable of considering the superposition effect of runoff hydrographs in the sewer pipes. The flow characteristics in the sewer pipes, such as the sewer layout, pipe diameter and slope, vary according to the design of the sewer system. In particular, when the sewer network is modified, the shapes of the runoff hydrographs in the sewer pipes also change because of the superposition effect. In this study, the sewer layout is designed to control and distribute the flows in the sewer pipes, while considering the runoff superposition effect, in order to reduce the inundation risk at each junction. This is accomplished by separating the inflows that enter into each junction by changing the way in which pipes are connected between junctions. And this model combines SWMM (Storm Water Management Model) to perform the hydraulic analysis for the flows in the sewer network. The current sewer layout was modified to minimize the peak outflow at outlet in Garak basin, Seoul, South Korea. As the results, the peak outflows at the outlet were decreased by approximately 20% for the design rainfall during 30 minutes and the total overflows were also decreased for the excessive rainfalls.

Valproic Acid Reduces Reactive Oxygen Species in Fibroblast of X-linked Adrenoleukodystrophy (부신백질형성장애증 섬유모세포에서 발프로산의 항산화능)

  • Kang, Joon Won;Quan, Zhejiu;Jang, Jiho;Kang, Hoon-Chul
    • Journal of the Korean Child Neurology Society
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    • v.23 no.2
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    • pp.45-50
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    • 2015
  • Purpose: X-linked adrenoleukodystrophy (X-ALD) is a fatal, axonal demyelinating, neurodegenerative disease, and is caused by mutations the in ABCD1 (ATP-binding cassette transporter subfamily D member 1). Oxidative damage of proteins caused by very long chain fatty acid accumulating in X-ALD, is an early event in the neurodegenerative cascade. We evaluated valproic acid (VPA) as a possible option for oxidative damage in X-ALD. Method: We generated fibroblast of the childhood cerebral ALD from patient. We evaluated mRNA (ribonucleic acid) level of ABCD2 by real-time polymerase chain reaction, and reactive oxygen species (ROS) levels by flow cytometry. Results: VPA increased expression of ABCD2 in both control and ALD fibroblast. ABCD2 gene mRNA expression was increased 1.76 fold in normal fibroblasts, and 2.22 fold in the X-ALD fibroblasts. ROS levels were decreased in VPA treated X-ALD fibroblast, especially in treated with 1 mM of VPA. ROS levels revealed 13.7 in control fibroblast, on the other hand, 5.83 in X-ALD fibroblast treated with 1 mM of VPA. Conclusion: We propose VPA as a promising novel therapeutic approach in oxidant damage that warrants further clinical investigation in X-ALD.

Differential Hrd1 Expression and B-Cell Accumulation in Eosinophilic and Non-eosinophilic Chronic Rhinosinusitis With Nasal Polyps

  • Chen, Kun;Han, Miaomiao;Tang, Mengyao;Xie, Yadong;Lai, Yuting;Hu, Xianting;Zhang, Jia;Yang, Jun;Li, Huabin
    • Allergy, Asthma & Immunology Research
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    • v.10 no.6
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    • pp.698-715
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    • 2018
  • Purpose: Hrd1 has recently emerged as a critical regulator of B-cells in autoimmune diseases. However, its role in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) remains largely unexplored. This study aimed to examine Hrd1 expression and B-cell accumulation and their possible roles in CRSwNP. Methods: Quantitative real-time polymerase chain reaction, immunohistochemistry, enzyme-linked immunosorbent assay and Western blotting were used to assess gene and protein expression in nasal tissue extracts. Cells isolated from nasal tissues and peripheral blood mononuclear cells were characterized by flow cytometry. Local antibody production was measured in tissue extracts with a Bio-Plex assay. Additionally, changes in Hrd1 expression in response to specific inflammatory stimuli were measured in cultured dispersed polyp cells. Results: Nasal polyps (NPs) from patients with eosinophilic CRSwNP (ECRS) had increased levels of Hrd1, B-cells and plasma cells compared with NPs from patients with non-eosinophilic CRSwNP (non-ECRS) or other control subjects (P < 0.05). The average Hrd1 levels in B-cells in NPs from ECRS patients were significantly higher than those from non-ECRS patients and control subjects (P < 0.05). NPs also contained significantly increased levels of several antibody isotypes compared with normal controls (P < 0.05). Interestingly, Hrd1 expression in cultured polyp cells from ECRS patients, but not non-ECRS patients, was significantly increased by interleukin-$1{\beta}$, lipopolysaccharide and Poly(I:C) stimulation, and inhibited by dexamethasone treatment (P < 0.05). Conclusions: Differential Hrd1 expression and B-cell accumulation between the ECRS and non-ECRS subsets suggests that they can exhibit distinct pathogenic mechanisms and play important roles in NP.