• Title/Summary/Keyword: Internal flow control

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A study on curvature radius affects condition of injection molding (사출성형조건이 곡율반경에 미치는 영향에 관한 연구)

  • Shin, Nam-Ho;Choi, Suk-Jong;Lee, Eun-Jong
    • Design & Manufacturing
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    • v.2 no.1
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    • pp.21-26
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    • 2008
  • In this research, jar die of cosmetic products which is difficult to produce variously was developed and can be obtain the productivity improvement by flexibility with two system which can control the die temperature. Flow analysis of jar was performed to find out the curvature radius of parts. In order to reduce thickness of jar, cycle time, deformation, uniform curvature of internal jar was maintained by rapid cooling. In external of dies, cooling channel, injection molding condition, die temperature control system were researched to make dies low temperature.

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Effects of Kamijihwang-tang on Immune Cells and Cytokines in OVA-induced Asthmatic Mice (가미지황탕(加味地黃湯)이 천식모델 생쥐의 면역세포 및 사이토카인에 미치는 영향)

  • Rah, Do-Gyun;Park, Yang-Chun
    • The Journal of Korean Medicine
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    • v.29 no.2
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    • pp.7-20
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    • 2008
  • Objectives: The purpose of this study wasto examine the effects of Kamijihwang-tang (KJHT) extracts on immune cells and cytokines in ovalbumin (OVA)-induced asthmatic mice. Methods: C57BL/6 mice were injected, inhaled and sprayed with OVA for 12 weeks (four times a week) for asthma induction. Two experimental groups were treated with different concentrations of KJHT (400 mg/kg and 200 mg/kg) extracts and cyclosporine A (10 mg/kg) for the later 8 weeks. At the end of the experiment, the mice lung, PLN and spleen were removed and immune cells were analyzed by flow cytometer, IL-5, IL-13, eotaxin-2, $TNF-{\alpha}$ were analyzed by real-time PCR, serum histamine was analyzed by ELISA kit. Results: $CD3^+$, $CD3e^-/CCR3^+$, $CD3e^+/CD69^+$, $CD4^+/CD25^+$, $B220^+/IgE^+$, and $CD3e^+/DX5^+$ cells in lung, PLN, and spleen of the KJHT group (400 mg/kg) decreased compared with that of the control group. $CD3e^+/CD69^+$, $CD4^+/CD25^+$, and $CD3e^+/DX5^+$ cells in lung, PLN, and spleen of the KJHT group (200 mg/kg), CD3+, $CD3e^-/CCR3^+$ cells in lung and PLN of the KJHT group (200 mg/kg) and $B220^+/IgE^+$ cells in lung and spleen of the KJHT group (200 mg/kg) decreased compared with that of the control group. mRNA expression of IL-5, IL-13, eotaxin-2, and $TNF-{\alpha}$ in lung tissue of the KJHT groups (400 mg/kg and 200 mg/kg) decreased compared with that of the control group. Histamine in serum of the KJHT group (400 mg/kg) decreased compared with that of the control group. Conclusions: These results suggest that KJHT can be utilized effectively in treating asthma because it significantly reduces inflammatory cells and cytokines.

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The Effect of Particulate Matter 10 from Asian Dust on the Production of Reactive Oxygen Species, TGF-β, NF-κB, PDGF-α and Fibronectin in MRC-5 Fibroblast Cells (폐 섬유모세포에서 황사의 미세먼지(Particulate Matter 10)가 활성산소족과 TGF-β, NF-κB, PDGF-α, Fibronectin의 생성에 미치는 영향)

  • Kim, Ah Hyun;Chon, Suyeon;Yoon, Jin Young;Kim, Yu Jin;Kyung, Sun Young;Lee, Sang Pyo;Park, Jeong Woong;Jeong, Sung Hwan
    • Tuberculosis and Respiratory Diseases
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    • v.67 no.6
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    • pp.528-535
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    • 2009
  • Background: Dust clouds blown by the wind from the arid deserts of Mongolia and Northeast China are known as Asian dust storms. Ambient particulate matter with a diameter <10 ${\mu}m$ ($PM_{10}$) is associated with the exacerbation of respiratory diseases and increased mortality of heart and lung disease patients. The fibrotic effects of $PM_{10}$ of Asian dust to pulmonary fibroblast cells are unknown. This study examined the production of reactive oxygen species (ROS), TGF-${\beta}$, NF-${\kappa}B$, PDGF-$\alpha$ and Fibronectin in fibroblasts exposed to Asian dust particles. Methods: Air samples were collected using a high volume air sampler (Sibata model HV500F) with an air flow of 500 L/min for at least 6 hours. The MRC-5 cells were exposed to 0, 50 and 100 ${\mu}g/mL$ of $PM_{10}$ for 24 hours. ROS was detected by measuring the level of oxidized DCF using FACS. TGF-$\beta$, NF-${\kappa}B$, PDGF-$\alpha$ and fibronectin were detected by western blotting. Results: There was no increase in the ROS, TGF-$\beta$ and PDGF-$\alpha$ levels in the MRC-5 cells exposed to $PM_{10}$. The NF-${\kappa}B$ level was higher in the MRC-5 cells exposed to 50 and 100 ${\mu}g/mL$ of $PM_{10}$ for 24 hours. The fibronectin level in the MRC-5 cells after 24 hours incubation with 50 ${\mu}g/mL$ $PM_{10}$ was significantly higher than the control group ($PM_{10}$ 50 ${\mu}g/mL$ 113.27${\pm}$8.65 of control, p=0.005). Conclusion: $PM_{10}$ from Asian dust increases the activation of NF-${\kappa}B$ and fibronectin expression in MRC-5 fibroblast cells.

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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Inhibitory Effects of Ssanghwa-tang on Lung Injury and Muscle Loss in a Cigarette Smoke Extract and Lipopolysaccharide-induced Chronic Obstructive Pulmonary Disease Mouse Model (표준담배추출물과 Lipopolysaccharide로 유발한 만성폐쇄성폐질환 동물모델에서 쌍화탕의 폐손상 및 근감소 억제 효과)

  • Jin-kwan Choi;Won-kyung Yang;Su-won Lee;Seong-cheon Woo;Seung-hyung Kim;Yang-chun Park
    • The Journal of Internal Korean Medicine
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    • v.45 no.1
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    • pp.11-30
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    • 2024
  • Objectives: This study evaluated the effects of Ssanghwa-tang (SHT) on lung injury and muscle loss in a COPD mouse model. Methods: C57BL/6 mice were challenged with cigarette smoke extract and lipopolysaccharide, and then treated with two concentrations of SHT (250 and 500 mg/kg). After sacrifice, the bronchoalveolar lavage fluid (BALF) or lung tissue was analyzed by cytospin, ELISA, real-time PCR, flow cytometry analysis, and H&E and Masson's trichrome staining. The grip strength of COPD mice was measured using a grip strength meter. The running time of COPD mice was measured by a treadmill test. Muscle tissue of the quadriceps was stained with H&E and Masson's trichrome staining. Results: SHT significantly inhibited the increase in neutrophil numbers in BALF and significantly decreased immune cell activity in BALF and lung tissue. It also significantly inhibited the increase in TNF-α, IL-17, and MIP2 in BALF. Real-time PCR analysis revealed that the mRNA expression of TNF-α, IL-17, MIP2, and TRPV1 in lung tissue showed a significant decrease compared with the control group. Lung tissue damage was significantly reduced in the histological analysis. The grip strength and running time of the COPD mice showed a significant decrease compared with the control group. In histological staining, SHT was found to reduce the damage to muscle tissue. Conclusions: This study indicates that SHT can be used as a therapeutic agent for COPD patients by inhibiting lung injury and muscle loss.

On the Development of the Generic CFCS for Engineering Level Simulation of the Surface Ship (공학수준 수상함 지휘무장통제체계 범용 모델 개발방안 연구)

  • Jung, Young-Ran;Han, Woong-Gie;Kim, Cheol-Ho;Kim, Jae-Ick
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.3
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    • pp.380-387
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    • 2011
  • In this paper, we considered the authoritative representation of Command and Fire Control System(CFCS) for the surface ship that was the engineering level model to develop system specifications and to analyze operational concepts on the concept design phase and to analyze military requirements, effectiveness and performance for the system. The engineering level model of CFCS can be used in simulation independently of the surface ship's type, and also it takes reuse, interoperability, and extension into consideration. The detailed sub-models, internal and external data interface, data flow among each sub-model, sensor and weapon models about the engineering level model of CFCS was defined. It was verified via engineering level simulations according to the V&V process.

Control law design of gas generator for secondary combustion (이차 연소를 위한 가스발생기의 압력 제어기법 연구)

  • Park, Ik-Soo;Lee, Jae-Yoon;Choi, Ho-Jin;Yoon, Hyun-Gull;Lim, Jin-Shik
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.565-568
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    • 2010
  • A pressure control law to regulate mass flow rate of gas generator is suggested. The governing equation is modeled by considering the burning rate of solid propellant and the conservation equation of gas generator. And then, a classical control law is applied after verifying the accuracy of dynamic model through comparing with ground test and internal ballistic results. The results show degradation of performance as shown in typical time varying system. To overcome this problem, an adaptive scheme is suggested and the performance is verified through numerical simulation.

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Multiaxial ratcheting assessment of Z2CND18.12N steel using modified A-V hardening rule

  • Xiaohui Chen;Yang Zhou;Wenwu Liu;Xu Zhao
    • Steel and Composite Structures
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    • v.49 no.1
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    • pp.1-17
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    • 2023
  • Based on Ahmadzadeh-Varvani hardening rule (A-V model), multiaxial ratcheting effect of Z2CND18.12N austenitic stainless steel is simulated by ABAQUS with user subroutine UMAT. The results show that the predicted results of the origin multiaxial A-V model are lower than the experimental data, and it is difficult to control ratcheting strain rate. In order to improve the predicted capability of A-V model, the A-V model is modified. In this study. Moreover, under the assumption of the von Mises yield criterion and normal plasticity flow rule, we develop a numerical algorithm of plastic strain with the improved model to implement the finite element calculation of the model. Internal iteration in the numerical algorithm was implemented with the Euler backward method, which calculated the trial strain for each equilibrium iteration using the consistent tangent matrix. With a user subroutine, the proposed model is programmed into ABAQUS for a user - executable version. By simulating the uniaxial ratcheting of a round bar made of Z2CND18.12N austenitic stainless steel, we observe that the predicted results simulated by ABAQUS with UMAT are compared with the experimental data. The predicted results of the improved multiaxial A-V model are consistent well with the experimental data.

The Effect of the Timing of Dexamethasone Administration in Patients with COVID-19 Pneumonia

  • Lee, Hyun Woo;Park, Jimyung;Lee, Jung-Kyu;Park, Tae Yeon;Heo, Eun Young
    • Tuberculosis and Respiratory Diseases
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    • v.84 no.3
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    • pp.217-225
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    • 2021
  • Background: Despite the proven benefits of dexamethasone in hospitalized coronavirus disease 2019 (COVID-19) patients, the optimum time for the administration of dexamethasone is unknown. We investigated the progression of COVID-19 pneumonia based on the timing of dexamethasone administration. Methods: A single-center, retrospective cohort study based on medical record reviews was conducted between June 10 and September 21, 2020. We compared the risk of severe COVID-19, defined as the use of a high-flow nasal cannula or a mechanical ventilator, between groups that received dexamethasone either within 24 hours of hypoxemia (early dexamethasone group) or 24 hours after hypoxemia (late dexamethasone group). Hypoxemia was defined as room-air SpO2 <90%. Results: Among 59 patients treated with dexamethasone for COVID-19 pneumonia, 30 were in the early dexamethasone group and 29 were in the late dexamethasone group. There was no significant difference in baseline characteristics, the time interval from symptom onset to diagnosis or hospitalization, or the use of antiviral or antibacterial agents between the two groups. The early dexamethasone group showed a significantly lower rate of severe COVID-19 compared to the control group (75.9% vs. 40.0%, p=0.012). Further, the early dexamethasone group showed a significantly shorter total duration of oxygen supplementation (10.45 days vs. 21.61 days, p=0.003) and length of stay in the hospital (19.76 days vs. 27.21 days, p=0.013). However, extracorporeal membrane oxygenation and in-hospital mortality rates were not significantly different between the two groups. Conclusion: Early administration of dexamethasone may prevent the progression of COVID-19 to a severe disease, without increased mortality.

A Review of Recent Clinical Studies of Transcutaneous Electrical Nerve Stimulation (TENS) on Xerostomia - PubMed and Domestic Studies (구강건조증에 대한 경피적전기신경자극(Transcutaneous electrical nerve stimulation)의 최근 임상연구 동향 고찰 - Pubmed와 국내 논문을 중심으로)

  • Lee, Eunkyung;Jun, Hyejin;Kim, Minjeong;Park, Jae-Woo;Ko, Seok-Jae
    • The Journal of Internal Korean Medicine
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    • v.43 no.3
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    • pp.375-386
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    • 2022
  • Objectives: The purpose of this study was to summarize current clinical study trends and results regarding transcutaneous electrical nerve stimulation (TENS) treatment for xerostomia. Methods: Studies published from 2017 to 2022 were searched on domestic databases and PubMed. The included studies were analyzed according to the year, language, study design, diagnosis xerostomia method, and TENS treatment method. Results: Nine studies were included. There were three randomized controlled trials (RCTs), three case series, one case report, one case-control study, and one cross-sectional study. Conventional TENS was used in seven studies, and acupuncture-like TENS (ALTENS) was used in one study. The most common TENS attachment site was externally on the skin overlying the parotid gland region, and the setting of TENS was 50 Hz-250 μs the most. In all nine studies, TENS was effective for xerostomia as assessed by salivary flow rate or quality of life questionnaire. Additionally, no persistent adverse events were reported after TENS treatment. Conclusions: TENS treatment for xerostomia can be considered effective and safe, so it can be used in clinical practice.