• Title/Summary/Keyword: Pressure Sensitive

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Weather-sensitive Diseases and Their Correlations with Meteorological Factors: Results from Academic Papers (학술논문 분석을 통한 기상민감질환 선정 및 기상인자와의 관련성고찰)

  • An, Hye Yeon;Jeong, Ju-Hee;Kim, Taehee;Yun, Jinah;Kim, Hyunsu;Oh, Inbo;Lee, Jiho;Won, Kyung-Mi;Lee, Young-Mi;Kim, Yoo-Keun
    • Journal of Environmental Science International
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    • v.25 no.6
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    • pp.839-851
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    • 2016
  • The effect of weather on disease was investigated based on results reported in academic papers. Weather-sensitive disease was selected by analyzing the frequency distributions of diseases and correlations between diseases and meteorological factors (e.g., temperature, humidity, pressure, and wind speed). Correlations between disease and meteorological factors were most frequently reported for myocardial infarction (MI) (28%) followed by chronic ischemic heart disease (CHR) (12%), stroke (STR) (10%), and angina pectoris (ANG) (5%). These four diseases had significant correlations with temperature (meaningful correlation for MI and negative correlations for CHR, STR, and ANG). Selecting MI, as a representative weather-sensitive disease, and summarizing the quantitative correlations with meteorological factors revealed that, daily hospital admissions for MI increased approximately 1.7%-2.2% with each $1^{\circ}C$ decrease in physiologically equivalent temperature. On the days when MI occurred in three or more patients larger daily temperature ranges ($2.3^{\circ}C$ increase) were reported compared with the days when MI occurred in fewer than three patients. In addition, variations in pressure (10 mbar, 1016 mbar standard) and relative humidity (10%) contributed to an 11%-12% increase in deaths from MI and an approximately 10% increase in the incidence of MI, respectively.

Influence of Combustor Pressure on Combustion Characteristics and Local Flame Reaction in the Partially Premixed Flames with $CH_4$, $C_2H_4$ and $C_3H_8$ (부분 예혼합 화염의 연소실 압력이 연료별(메탄, 에틸렌, 프로판) 연소특성과 국소 화염 반응에 미치는 영향)

  • Kim, Jong-Ryul;Son, Je-Ha;Noh, Young-Gu;Kim, Yun-Dong;Choi, Gyung-Min;Kim, Duck-Jool
    • Journal of the Korean Society of Combustion
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    • v.15 no.4
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    • pp.29-36
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    • 2010
  • An experimental study was conducted for three different fuels($CH_4$, $C_2H_4$ and $C_3H_8$) to investigate the combustion characteristics and the local reaction intensity with combustor pressure(-30kpa~30kpa). Regardless of fuel composition, EINOx decreased with reducing pressure decreased. Structure and combustion characteristics were also largely affected by the combustor pressure. In addition, reaction intensity in terms of the changing combustor pressure and equivalence ratio was investigated. Combustion reaction in higher than atmospheric pressure was very active than the lower combustor pressure. When the combustor pressure is lower than the atmospheric pressure, the overall reactivity is noticeably enhanced due to the elevated diffusion process of unburned mixture. It was found that the combustion characteristics of the methane and propane flames are considerably influenced by the pressure while those of ethylene flame are less sensitive to the combustor pressure.

Pressure Sensitive Device Using Conductive and Porous Structures (전도성 다공성 구조 압력감지소자)

  • So, Hye-Mi;Park, Cheolmin;Chang, Won Seok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.7
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    • pp.601-605
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    • 2014
  • Porous conductors are known to demonstrate excellent electrical, mechanical, and chemical resistance. These porous conductors demonstrated potential applications in various fields such as electrodes for supercapacitors, flexible heaters, catalytic electrodes, and sorbents. In this study, we described a pressure sensitive device using conductive and porous sponges. With an extremely simple "dipping and drying" process using a single-walled carbon nanotube (SWCNT) solution, we produced conductive sponges with sheet resistance of < $30k{\Omega}/sq$. These carbon nanotube sponges can be deformed into any shape elastically and repeatedly compressed to large strains without collapse. The pressure sensors developed from these sponges demonstrated high resistance change under pressure of up to a half of their initial resistance.

Inflatable Mouse: Volume-adjustable Mouse with Air-pressure-sensitive Input and Haptic Feedback (부풀어지는 마우스: 기압센서를 이용한 입력과 햅틱 피드백을 갖는 부피가 변하는 마우스)

  • Kim, Seok-Tae;Lee, Bo-Ram;Kim, Hyun-Jung;Nam, Tek-Jin;Lee, Woo-Hun
    • 한국HCI학회:학술대회논문집
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    • 2008.02b
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    • pp.323-328
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    • 2008
  • Inflatable Mouse is a volume-adjustable user interface. It can be inflated up to the volume of a familiar mouse, but be deflated and stored flat in a PC card slot of a laptop computer when not in use. Inflatable Mouse functions just like a typical mouse; moreover, it provides new interaction techniques by sensing the air pressure in the balloon of the mouse. It also addresses some issues associated with pressure-sensing interactions such as the lack of bi-directional control and the lack of effective feedback. Moreover, it can be used as both a control tool and a display tool. In this paper, the design of an Inflatable Mouse prototype is described and potential application scenarios such as zooming in/out and fast scrolling using pressure control are explained. We also discuss the potential use of Inflatable Mouse as an emotional communication tool.

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Nonlinear Acoustic-Pressure Responses of H2/Air Counterflow Diffusion Flames (수소/공기 대향류 확산화염의 비선형 음향파 응답특성에 관한 연구)

  • Kim, Hong-Jip;Chung, Suk-Ho;Sohn, Chae-Hoon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.8
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    • pp.1158-1164
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    • 2003
  • Steady-state structure and acoustic-pressure responses of $H_2$/Air counterflow diffusion flames are studied numerically with a detailed chemistry in view of acoustic instability. The Rayleigh criterion is adopted to judge acoustic amplification or attenuation from flame responses. Steady-state flame structures are first investigated and flame responses to various acoustic-pressure oscillations are numerically calculated in near-equilibrium and near-extinction regimes. The acoustic responses of $H_2$/Air flame show that the responses in near-extinction regime always contribute to acoustic amplification regardless of acoustic-oscillation frequency Flames near extinction condition are sensitive to pressure perturbation and thereby peculiar nonlinear responses occur, which could be a possible mechanism in generating the threshold phenomena observed in combustion chamber of propulsion systems.

Numerical study on Comparison of Self-Pressurization Behavior of Liquid Nitrogen Cryostat for Umbilical Cord Blood Storage System Design

  • Mahfud, M.I.;Phil, K.E.
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.409-414
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    • 2009
  • Since cryogens are stored at very low temperatures, the cryogenic storage systems are quite sensitive to heat leaks. Even though the vessel operated under sealed condition with vacuum insulation and reflective coatings are used, the heat leakage into the vessel is still unavoidable. Therefore, this paper concerns with numerical study of self-pressurization used to analysis the optimum design with the variation volume fraction, effect of heat flux and storage pressure of liquid nitrogen. The result shows that as the volume fraction increases, the pressure rise reduces and the relatively at atmosphere pressure is better than the higher one. In addition, higher heat flux leads the pressure rise increases faster than low one. The additional of heat pipe system to reduce the pressure rise rate also has been done. By this comparison, the optimum design for storage umbilical cord blood can be selected.

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Analysis of spray sodium fire phenomena in the containment vessel (격납용기내에서 분무형 나트륨화재 현상 해석)

  • 조병렬;권선길;황성태
    • Journal of the Korean Society of Safety
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    • v.11 no.2
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    • pp.79-88
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    • 1996
  • A hypothetical accident in the containment vessel of liquid metal reactor could cause a pressure, temperature rise, and a strong aerosol release. The computer codes relating to the modelization of these accident make it necessary to use various input parameter, among which is the dynamic shape factor of aerosols produced. Combustion experiments of sodium spray fire carried out in a closed vessel, which was vertical cylinder made of 1.2m in diameter and 1.8m hight with a volume of 1.7$m^3$. The results of theoretical analysis presented here was compared to data obtained from experiments. The experimental results were summarized as follows. 1) The aerodynamic diameter and geometric diameter of aerosols are decreasing with increasing of injection pressure and injection temperature of sodium 2) The dynamic shape factor of aerosol is proportional to the aerodynamic diameter for a given particle. 3) The correspondence between the aerodynamic diameter and geometric diameter can be as $D_{ae}=0.70 D_{ge}$. 4) Peak pressure rose with increase in pressure and temperature of injection sodium, being more sensitive to the injection pressure than the injection temperature.

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Quantitative Evaluation of Driver's Postural Change and Lumbar Support Using Dynamic Body Pressure Distribution (동적 체압 분포를 이용한 운전 자세 변화와 요추지지대의 정량적 평가)

  • Na, Seok-Hui;Im, Seong-Hyeon;Jeong, Min-Geun
    • Journal of the Ergonomics Society of Korea
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    • v.22 no.3
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    • pp.57-73
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    • 2003
  • Although body pressure distribution is sensitive to movements and is relatively simple to measure even in small space, there are few researches involving applications to driver's posture and its change. The main objective in this study is the application of body pressure distribution measurements for the prediction of the driver's posture and its change. This requires quantitative analyses of the dynamic body pressure distribution, which is the change of body pressure distribution with time. The experiment involved 16 male subjects who drove for 45 minutes in a seating buck. Measurement time, stature group, and lumbar support prominence were selected as independent variables, with subjective ratings of driver's discomfort, body posture data of hip, torso. knee angle, and body pressure data variables as dependent variables. The body pressure change variables and subjective ratings were found to increase as the measurement time increased and body pressure ratio variables reflected the torso angle. From the results and analysis of the body posture data and subjective rating results, it was predicted that the seats and the design of the lumbar supports used in the experiment was not fit for tall subjects, which could also be confirmed through the body pressure distribution data.

Fundamental Studies of the Electrical Characteristics of the Glow Discharge for the Development of HPLC Detector (글로우방전을 이용한 액체크로마토그라피 검출기 개발을 위한 기초특성연구)

  • 이현주;김효진
    • YAKHAK HOEJI
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    • v.39 no.4
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    • pp.427-432
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    • 1995
  • The plasma oscillation has been observed in an argon pressure between a tungsten anode and cathode consisting of an aqueous conducting solution. The effects of experimental parameters on the electrical characteristics of the glow discharge have been studied. The experimental parameters include the anode-cathode distance, pressure, methanol flow rate, and cathode materials. The glow discharge with liquid cathode and solid anode showed the potential sensitive detector for HPLC

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Salt-sensitive genes and their relation to obesity (소금민감성유전자와 비만)

  • Cheon, Yong-Pil;Lee, Myoungsook
    • Journal of Nutrition and Health
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    • v.50 no.3
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    • pp.217-224
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    • 2017
  • Purpose: Although it is well known thatmortality and morbidity due to cardiovascular diseases are higher in salt-sensitive subjects than in salt-resistant subjects, their underlying mechanisms related to obesity remain unclear. Here, we focused on salt-sensitive gene variants unrelated to monogenic obesity that interacted with sodium intake in humans. Methods: This review was written based on the modified $3^rd$ step of Khans' systematic review. Instead of the literature, subject genes were based on candidate genes screened from our preliminary Genome-Wide Association Study (GWAS). Finally, literature related to five genes strongly associated with salt sensitivity were analyzed to elucidate the mechanism of obesity. Results: Salt sensitivity is a measure of how blood pressure responds to salt intake, and people are either salt-sensitive or salt-resistant. Otherwise, dietary sodium restriction may not be beneficial for everyone since salt sensitivity may be associated with inherited susceptibility. According to our previous GWAS studies, 10 candidate genes and 11 single nucleotide polymorphisms (SNPs) associated with salt sensitivity were suggested, including angiotensin converting enzyme (ACE), ${\alpha}$-adducin1 (ADD1), angiotensinogen (AGT), cytochrome P450 family 11-subfamily ${\beta}$-2 ($CYP11{\beta}$-2), epithelial sodium channel (ENaC), G-protein b3 subunit (GNB3), G protein-coupled receptor kinases type 4 (GRK4 A142V, GRK4 A486V), $11{\beta}$-hydroxysteroid dehydrogenase type-2 (HSD $11{\beta}$-2), neural precursor cell-expressed developmentally down regulated 4 like (NEDD4L),and solute carrier family 12(sodium/chloride transporters)-member 3 (SLC 12A3). We found that polymorphisms of salt-sensitive genes such as ACE, $CYP11{\beta}$-2, GRK4, SLC12A3, and GNB3 may be positively associated with human obesity. Conclusion: Despite gender, ethnic, and age differences in genetics studies, hypertensive obese children and adults who are carriers of specific salt-sensitive genes are recommended to reduce their sodium intake. We believe that our findings can contribute to the prevention of early-onset of chronic diseases in obese children by facilitating personalized diet-management of obesity from childhood to adulthood.