Empirical Study on The Heat Exchange Effectiveness of A Cross-flow Thermoelectric Air To Air Heat Pump Unit

A thermoelectric module (TEM), non-vapor compression heat pump, has attracted research interesting as a substitution of the conventional vapor compression heat pump. However, there are few studies for analysing a heat exchange effectiveness and performance of TEM for application to the HVAC system. The purpose of this research is to propose an empirical model for predicting the heat exchange effectiveness in air heat-pump system using TEM. The proposed system consists of aflat plate fin array that is heat exchanger integrated TEM for cooling and heating. In this study, the enthalpy efficiency is adopted as the TEM heat exchange performance index. And then, the inlet and outlet air temperature and humidity ratio, air flow rate at the heating and cooling side, TEM surface temperature, heat exchange area, and input direct current (DC) to the TEM are measured to calculate the enthalpy efficiency. The data were statistically analysed by the response surface methodology (RSM) and analysis of variance (ANOVA). Using the response surface methodology (RSM) and analysis of variance (ANOVA), the experimental data were statistically analyzed. Design parameters had significant impact on the heat exchange effectiveness of the flat plate heat exchanger integrated TEM for air cooling and heating. Consequently, two polynomial equations that predict heat exchange effectiveness at the cold and hot sides of the TEM heat pump were derived as a function of the selected design parameters and were used to calculate the outlet air temperature at cooling and heating side

Management of a Submacular Hemorrhage Secondary to Age-Related Macular Degeneration: A Comparison of Three Treatment Modalities

This paper aims to compare the effects of three treatment modalities for a submacular hemorrhage (SMH) secondary to exudative age-related macular degeneration (AMD). Seventy-seven patients with an SMH were divided into three groups: small-sized (optic disc diameter (ODD) ≥ 1 to < 4), medium-sized (ODD ≥ 4 within the temporal arcade) and large-sized (ODD ≥ 4, exceeding the temporal arcade). Patients received anti-vascular endothelial growth factor (anti-VEGF) monotherapy, pneumatic displacement (PD) with anti-VEGF or a vitrectomy with a subretinal tissue plasminogen activator (tPA) and gas tamponade based on the surgeon’s discretion. The functional and anatomical outcomes were evaluated. Among the 77 eyes, 45 eyes had a small-sized, 21 eyes had a medium-sized and 11 eyes had a large-sized SMH. In the small-sized group, all treatment modalities showed a gradual best-corrected visual acuity (BCVA) improvement with high hemorrhagic regression or displacement rates (over 75%). In the medium-sized group, PD and surgery were associated with better BCVA with more displacement than anti-VEGF monotherapy (67% and 83%, respectively, vs. 33%). In the large-sized group, surgery showed a better visual improvement with a higher displacement rate than PD (86% vs. 25%). Our findings demonstrated that visual improvement can be expected through appropriate treatment strategy regardless of the SMH size. In cases with a larger SMH, invasive techniques including PD or surgery were more advantageous than anti-VEGF monotherapy

Low Compressibility at the Transition Zone of Railway Tracks Reinforced with Cement-Treated Gravel and a Geogrid under Construction

In the transition zone of railway tracks, track irregularities occur frequently due to differential settlement, which arises from the difference between the vertical supporting stiffness of the abutment and the backfill. This is disadvantageous because it increases the maintenance requirements and deteriorates the ride quality. To address this challenge, this study proposes a strategy involving the application of cement-treated gravel reinforced with geogrids and rigid facing walls. The reinforced subgrade for railways (RSR), which can reduce residual settlement through the initial construction of the backfill reinforced with geogrids and the subsequent development of the rigid facing wall, was constructed at the transition zone with cement-treated gravel as the backfill material. The long-term behaviors during and after construction on the RSR for a period of 16 months were evaluated by analyzing the surface and ground settlements, horizontal earth pressure, and geogrid strain. The minor net settlement of the reinforced backfill converges at the early stage of subgrade construction, and the horizontal earth pressure was approximately reduced to the level of 54–63% of the Rankine active earth pressure

Low Compressibility at the Transition Zone of Railway Tracks Reinforced with Cement-Treated Gravel and a Geogrid under Construction

In the transition zone of railway tracks, track irregularities occur frequently due to differential settlement, which arises from the difference between the vertical supporting stiffness of the abutment and the backfill. This is disadvantageous because it increases the maintenance requirements and deteriorates the ride quality. To address this challenge, this study proposes a strategy involving the application of cement-treated gravel reinforced with geogrids and rigid facing walls. The reinforced subgrade for railways (RSR), which can reduce residual settlement through the initial construction of the backfill reinforced with geogrids and the subsequent development of the rigid facing wall, was constructed at the transition zone with cement-treated gravel as the backfill material. The long-term behaviors during and after construction on the RSR for a period of 16 months were evaluated by analyzing the surface and ground settlements, horizontal earth pressure, and geogrid strain. The minor net settlement of the reinforced backfill converges at the early stage of subgrade construction, and the horizontal earth pressure was approximately reduced to the level of 54–63% of the Rankine active earth pressure

A Study on the Anomaly Detection of Engine Clutch Engagement/Disengagement Using Machine Learning for Transmission Mounted Electric Drive Type Hybrid Electric Vehicles

Transmission mounted electric drive type hybrid electric vehicles (HEVs) engage/disengage an engine clutch when EV↔HEV mode transitions occur. If this engine clutch is not adequately engaged or disengaged, driving power is not transmitted correctly. Therefore, it is required to verify whether engine clutch engagement/disengagement operates normally in the vehicle development process. This paper studied machine learning-based methods for detecting anomalies in the engine clutch engagement/disengagement process. We trained the various models based on multi-layer perceptron (MLP), long short-term memory (LSTM), convolutional neural network (CNN), and one-class support vector machine (one-class SVM) with the actual vehicle test data and compared their results. The test results showed the one-class SVM-based models have the highest anomaly detection performance. Additionally, we found that configuring the training architecture to determine normal/anomaly by data instance and conducting one-class classification is proper for detecting anomalies in the target data

Strong optical coupling between mutually orthogonal plasmon oscillations in a silver nanosphere-nanowire joined system

A top-to-bottom joined system consisting of a silver nanowire and nanospheres was fabricated by embedding silver nanospheres on a glass or silicon substrate on which 3-aminothiophenol as an analyte molecule was adsorbed, and then placing silver nanowires on the substrate to make gap sites between a nanowire and nanospheres. In the far-field Raman measurements, the sphere under the wire exhibited more than 60 times higher Raman enhancement than isolated spheres. The surface enhanced Raman scattering (SERS) spectra obtained by the 647.1 nm excitation showed highly polarized feature, exhibiting ca. 4 times higher SERS intensity for the electric field parallel to the wire axis than that perpendicular to the wire axis while those by the 514.5 nm excitation showed non-polarized feature against the incident electric field direction. The polarized feature by the 647.1 nm excitation is explained in terms of optical coupling in a vertical direction to the substrate plane, between the silver nanosphere and the longitudinal surface plasmon mode of the nanowire. The longitudinal plasmon of the nanowire functions as an antenna of the incident radiation field in this type of coupled plasmon mode, to yield the confined field. Near-field two-photon excitation imaging measurements as well as numerical calculations of the localized electric field around the system support this idea and indicate that the coupling between the surface plasmon of silver nanospheres and the longitudinal mode of silver nanowires is site-selective.This work was supported by the Bio & Medical Technology Development Program (Grant No. 2012-0006077) and the Pioneer Research Center Program (Grant No. 2012-0000448) of the National Research Foundation (NRF) funded by the Ministry of Education, Science and Technology of Korea. The work at Japan was supported by Grants-in-Aid for Scientific Research (Grant No. 18205004, 18685003, 22655007, 22225002, 24655020, and 24350014) from the Japan Society for the Promotion of Science and that on Priority Area Strong Photon-Molecule Coupling Fields (Grant No. 19049015) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan and that from Research Foundation for Opto-Science and Technology and Inamori FoundationOAIID:oai:osos.snu.ac.kr:snu2013-01/102/0000027849/3SEQ:3PERF_CD:SNU2013-01EVAL_ITEM_CD:102USER_ID:0000027849ADJUST_YN:YEMP_ID:A075905DEPT_CD:718CITE_RATE:3.573FILENAME:첨부된 내역이 없습니다.DEPT_NM:화학교육과EMAIL:[email protected]_YN:YCONFIRM:

Magnetic surface-enhanced Raman spectroscopic (M-SERS) dots for the identification of bronchioalveolar stem cells in normal and lung cancer mice

Bronchioalveolar stem cells (BASCs) play an important role in the development of cancer. To study the characterization of BASCs, their isolation and purification are important. However, the cells are very rare in tissues and the available methods of isolating them are limited. The current study was performed to isolate BASCs in the murine lung using magnetic nanoparticle-based surface-enhanced Raman spectroscopic dots (M-SERS Dots). We used K-ras(LA1) mice, a laboratory animal model of non-small cell lung cancer of human, and C57BL/6 mice having the same age as a control. We compared the BASCs between 2 species by FACS analysis with 4 markers of BASCs, CCSP, SP-C, CD34, and Sca-1. We found that BASCs were more abundant in the K-ras(LA1) mice than in the C57BL/6 mice. Also, the M-SERS Dot-mediated positive selection of the CD34(pos) cells enabled the BASCs to be enriched to an approximately 4- to 5-fold higher level than that in the case without pre-separation. In summary, our study demonstrates the potential of using M-SERS Dots as a sorting system with very effective isolation of BASCs and multiplex targeting probe, showing that they may play an effective role in the study of BASCs in the future. (C) 2009 Elsevier Ltd. All rights reserved.