• Title/Summary/Keyword: flow control

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A Platform Study of Fuel Consumption Measurements for an Excavator in Motion (동작중 굴삭기의 연료소모량 측정을 위한 측정 방법 기반 연구)

  • Kang, Ju Young;Choi, Jin Goo;Lee, Jeong Ho;Lee, Chung Geun;Ko, Sang Chul;Lee, Daeyup
    • Journal of Drive and Control
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    • v.14 no.1
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    • pp.35-40
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    • 2017
  • Whereas fuel economy of a vehicle is measured using a chassis dynamometer, that of construction machinery such as an excavator shall be presumably measured using simulated work cycle. In order to measure fuel consumption under a simulated work cycle, a measurement methodology, while excavator operates in dynamic(transient) motion, needs to be examined and developed. In this work, three methods (gravimetry, ECU CAN signal and mass flow meter) are studied and compared. This work reveals that when ECU CAN signal is properly calibrated and evaluated, compared to gravimetry or mass flowmeter, it could be used to measure fuel consumption with accuracy and thus for approval of the fuel economy of construction machinery.

The Effect of Docosahexaenoic Acid on Brain Function and Acetylcholine Level in Cerebral Cortex of Electroconvulsive Shock Induced Mice (Docosahexaenoic acid가 전기충격성 뇌장애 마우스의 기억력 및 Acetylcholine량 변화에 미치는 영향)

  • 김문정;신정희;윤재순
    • YAKHAK HOEJI
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    • v.39 no.3
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    • pp.231-242
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    • 1995
  • Electroconvulsive shock (ECS) increases the activity of acetylchohnesterase and decreases in brain acetylcholine levels. A large amount of free fatty acids accumulated in the brain tissue affects cerebral blood flow, brain edema and inflammation and results in brain injury. The present study examined the effect of docosahexaenoic acid (DHA) and D,L-pyroglutamic acid (D,L-PCA) on the learning and memory deficit using the passive avoidance failure technique and on the change of acetylcholine and choline level in the cerebral cortex of ECS-induced mice. The application of ECS (25mA, 0.5sec) induced a significant decrease in memory function for 30 min. ECS-induced a significant decrease in cortical acetylcholine and choline levels 1 min following the ECS application, which were almost recovered to ECS control level after 30 min. DHA (20 mg/kg, i.p.). administered 24 hr before shock. prevented the ECS-induced passive avoidance failure and the decrease of acetylcholine level 1 min following the ECS application. DHA failed to elicit a change in cortical choline level. DHA did not affect memory function and the cortical Ach and choline level of normal mice. The administration of D,L-PCA (500 mg/kg, i.p.) increased the effect of DHA on memory function and the change of cortical acetylcholine level of ECS induced mice. These results suggest that DHA treatment may be contributed to the prevention against memory deficit, and to the activation of cholinergic system in the ECS induced mice.

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Characteristics and Control of Nonpoint Pollutants in Railway Station (철로 역사에서 발생 가능한 비점오염물질의 특성 및 관리방안)

  • Oa Seong Wook;Kim Lee-Hyung
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1695-1700
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    • 2004
  • Nonpoint pollutants were monitored on railway station land use. Lots of pollutant mass were washed-off in a first hour. The 95$\%$ confidence interval of pollutant concentrations ranges from 61.6 to 115.4 mg/L for TSS(mean= 88.50 mg/L). 103.8$\∼$244.1 mg/L for COD(mean= 174 mg/L) and 7.68$\∼$17.32 mg/L for Oil & Grease(mean= 12.5 mg/L). The various metals were also washed-off during storm runoff from railway station. The ranges of 95$\%$ confidence intervals were 39.2$\∼$84.0 ug/L for total Cu(mean= 61.6 ug/L), 14.0 $\∼$ 25.8 ug/L for total Pb(mean= 19.9 ug/L) and 182.2 $\∼$ 376.1 ug/L for total Zn(mean= 279.2 ug/L). As a result of this research, we concluded that up to 50$\%$ of the total pollutant mass can be removed when first 30$\%$ of the total flow are treating, and it can be a first flush criteria for best management practices.

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Study of aerodynamic characteristic for a device controlling lift force on pantograph for Tilting train eXpress (TTX) (고속 틸팅열차의 판토그라프 양력조절장치 형상 설계 연구)

  • Ko Taehwan;Han Seong-Ho
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.467-471
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    • 2004
  • The development of a tilting train with construction of electric line on the conventional railway is required for speed-up on the conventional railway with many curving sections. For development of tilting train, the study and development of the tilting system and tilting bogie having the different mechanism with a general high speed train will play a main role for improving the technology in the field of Korean railway. The study and development of the pantograph tilting mechanism in order to keep a good contact behavior between a pantograph and a contact wire by tilting a pantograph on the opposite direction of the vehicle tilting direction. In this study, we analyzed the aerodynamic characteristic of a developing pantograph on the tilting train and obtained the contact force with catenary by aerodynamic lift force by the aerodynamic analysis. We also performed the numerical analysis for design the device controlling lift force on a pantograph. From the aerodynamic simulation and parameter study for a device to control the lift force, we will suggest the various shape and the optimal shape of it corresponding to a developing tilting pantograph. The Fluent software is used for the calculation of flow profile in this study.

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M_CSPF: A Scalable CSPF Routing Scheme with Multiple QoS Constraints for MPLS Traffic Engineering

  • Hong, Daniel W.;Hong, Choong-Seon;Lee, Gil-Haeng
    • ETRI Journal
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    • v.27 no.6
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    • pp.733-746
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    • 2005
  • In the context of multi-protocol label switching (MPLS) traffic engineering, this paper proposes a scalable constraintbased shortest path first (CSPF) routing algorithm with multiple QoS metrics. This algorithm, called the multiple constraint-based shortest path first (M_CSPF) algorithm, provides an optimal route for setting up a label switched path (LSP) that meets bandwidth and end-to-end delay constraints. In order to maximize the LSP accommodation probability, we propose a link weight computation algorithm to assign the link weight while taking into account the future traffic load and link interference and adopting the concept of a critical link from the minimum interference routing algorithm. In addition, we propose a bounded order assignment algorithm (BOAA) that assigns the appropriate order to the node and link, taking into account the delay constraint and hop count. In particular, BOAA is designed to achieve fast LSP route computation by pruning any portion of the network topology that exceeds the end-to-end delay constraint in the process of traversing the network topology. To clarify the M_CSPF and the existing CSPF routing algorithms, this paper evaluates them from the perspectives of network resource utilization efficiency, end-to-end quality, LSP rejection probability, and LSP route computation performance under various network topologies and conditions.

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A literatual study on the external treatment of sprain and strain using the herb (염좌(捻挫)의 약물외치요법(藥物外治療法)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Yang, Gi-Young;Kim, Young-Il;Hong, Kwon-Eui;Yim, Yun-Kyoung;Lee, Hyun
    • Journal of Haehwa Medicine
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    • v.14 no.1
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    • pp.83-94
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    • 2005
  • 1. The external treatment of sprain and strain using the herb used adhesive(貼敷), using soaking in medicinal smoke to focuses and rinsing methods(熏洗), rubbing(擦擦) and hot compression(熱熨). 2. In the external treatment of sprain and strain using the herb, Adhesive(貼敷) is used most. Because Adhesive(貼敷) brings fast reactions, has less side effects, and can control the processing time. 3. The effects of herbs used in this external treatment are almost the same as oral herb-medicines such as, promoting blood flow to remove blood stasis(活血化瘀), relieving rheumatic conditions(祛風濕), and removing obstruction in meridians and collaterals(通經絡).

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Effect of Scutellariae Radix extract on immune cells in OVA-induced asthmatic mice lung tissue (황금이 천식모델 생쥐의 폐조직내 면역세포에 미치는 영향)

  • Park, Gil-Byung;Park, Yang-Chun
    • Journal of Haehwa Medicine
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    • v.14 no.1
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    • pp.35-42
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    • 2005
  • Objective : The purpose of this research is to examine the effects of Scutellariae Radix(SR) extract on immune cells in ovalbumin(OVA)-induced asthmatic mice. Methods : In vitro, C57BL/6 mice were exposed to OVA for 6 weeks. The mice lungs were taken out, chopped, grinded with collagenase and activated by rIL-3/rIL-5. The lung cells were treated with SR extract and analyzed by a flow cytometer. Results : The population of granulocytes/lymphocytes, CD3e-/CCR3+, CD69+/CD3e+, CD23+/B220+, CD4+ cells in the SR group in vitro decreased and population of CD8+ cells in the 100 and $10{\mu}g/m{\ell}$ SR group in vitro decreased, compared with that of control group. Conclusion : The results of this study support a role for SR as an effective treatment for asthma in its experimental success in significantly decreasing inflammation and asthma reactions.

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Heat Transfer on a Jet Vane Surface Installed in a Rocket Nozzle (로켓노즐에 장착된 제트베인 표면의 열전달 특성)

  • Yu Man Sun;Cho Hyung Hee;Hwang Ki Young;Bae Ju Chan
    • Journal of the Korean Society of Propulsion Engineers
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    • v.9 no.1
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    • pp.9-16
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    • 2005
  • Jet vane is an useful component which is installed at the end of a nozzle for the purpose of the posture control and the secure controlling stability during the initial launching of a rocket. During several seconds from its initial launching moment, the JV driving part is heated due to the direct contact of the vane with the combusted gas and the vane is ablated mechanically or chemically. In this study, as the fundamental study for the thermal analysis of jet vane, the heat transfer into a jet vane which is located in the uniform supersonic flow field is calculated. For this, boundary layer integral method and finite difference method are used simultaneously. Based on the thermal boundary conditions derived from the analysis, the transient heat conduction in the vane is also calculated.

Analysis of sewage treatment process for the improvement of T-N removal process (T-N 제거공정 개선을 위한 하수처리장 공정 분석)

  • Shin, Choon Hwan
    • Journal of Environmental Science International
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    • v.27 no.2
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    • pp.99-107
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    • 2018
  • In order to design the improvement process for T-N removal, the treatment process of Suyoung, Gangbyeon, and Noxan sewage treatment plants (STP) in Busan was anlayzed. Suyoung STP shows a T-N removal efficiency of about 69.8% with MLE(Modified Ludzack ettinger) and A2O+MBR. However, it is necessary to improve the process to maintain over DO of 1 mg/L and is required to install a flow control tank to minimize the rainfall effect. Gangbyun STP shows a about 70.2% T-N removal efficiency with A2O+GFF(gravity fiber filtration). However, in order to improve T-N removal efficiency, it is needed to install MLE process to treat recycle water. Noksan STP shows a T-N removal efficiency of about 71.0% with MLE+Chemical treatment and shows stable T-N concentration in effluent. However, it is required a toxic chemical management process because bad wastewater flows into the STP, also is necessary a process improvement in order to increase internal recycling ratio. Especially, it is required a process improvement to increase HRT of nitrification tank because Suyoung and Gangbyeon STPs shows low nitrification efficiency during winter season.

Magnetic Resonance Imaging in Thoracic Disease (흉부질환의 자기공명영상)

  • Song, Koun-Sik
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.4
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    • pp.345-352
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    • 1993
  • The role of magnetic resonance(MR) imaging in the evaluation of thoracic disease has been limited Nontheless, MR has inherent properties of better contrast resolution than CT allowing tissue-specific diagnosis. MR has capability of direct imaging in sagittal, coronal, and oblique planes which provide better anatomic information than axial images of CT such as lesions in the pulmonary apex, aorticopulmonary window, peridiaphragmatic region, and subcarinal region. MR is sensitive to blood flow making it an ideal imaging modality for the evaluation of cardiovascular system of the thorax without the need for intravenous contrast media. Technical developments and better control of motion artifacts have resulted in improved image quality, and clinical applications of MR imaging in thoracic diseases have been expanded. Although MR imaging is considered as a problem-solving tool in patients with equivocal CT findings, MR should be used as the primary imaging modality in the following situations: 1) Evaluation of the cardiovascular abnormalities of the thorax 2) Evaluation of the superior sulcus tumors 3) Evaluation of the chest wall invasion or mediastinal invasion by tumor 4) Evaluation of the posterior mediastinal mass, especially neurogenic tumor 5) Differentiation of fibrosis and residual or recurrent tumor, especially in lymphoma 6) Evaluation of brachial plexopathy With technical developments and fast scan capabilities, clinical indications for MR imaging in thorax will increase in the area of pulmonary parenchymal and pulmonary vascular imaging.

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