• Title/Summary/Keyword: changing pressure

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A Gripping System Capable of Simultaneous Implementation of Pneumatic Gripper and Vacuum Gripper Using a Single Pump (단일 펌프를 이용하여 공압 그리퍼와 진공 그리퍼의 동시 구현이 가능한 그리핑 시스템의 개발)

  • Tae Hwa Hong;Jae-Bok Song
    • The Journal of Korea Robotics Society
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    • v.18 no.4
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    • pp.456-462
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    • 2023
  • In recent years, the use of robot arms has increased rapidly in both industrial and service applications. Unlike production sites, where only one type of gripper is used for productivity, service sites often use a tool changer to replace fingered grippers or vacuum grippers to cover various objects to be grasped. To this end, a tool changer-based pneumatic grasping system was developed in this study. In order to simultaneously use a positive pressure-based pneumatic gripper and a negative pressure-based vacuum gripper, a small vane pump capable of generating positive and negative pressures depending on the direction of rotation was developed. Experiments with actual prototypes have shown that the pneumatic system based on the developed vane pump can effectively realize both pneumatic grippers and vacuum grippers.

Incomplete Decisions on Reward-Based Crowdfunding Platforms: Exploring Motivations from Temporal and Social Perspectives

  • KwangWook Gang;Hoon S. Cha;Ilyoo B. Hong
    • Asia Marketing Journal
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    • v.26 no.1
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    • pp.1-10
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    • 2024
  • This study explores incomplete decision-making dynamics on reward-based crowdfunding platforms, focusing on temporal and social factors influencing backers' decisions. Utilizing the temporal aspect (i.e., pledging campaign phase) and social aspect (i.e., current pledged amount ratio) as stimuli within the stimulus-organism-response framework, our findings reveal that nearly 50.9% of respondents change their initial decisions, highlighting widespread incomplete information processing. Backers are more prone to altering decisions under heightened time pressure and display herding behaviors. Furthermore, backers exhibit an increased likelihood of changing decisions under heightened time pressure, coupled with a greater chance that the pledged goal amount will not be achieved. The study discusses theoretical and practical implications.

Effect of Health Behavior and Obesity Indices on Blood Pressure in Peru Low-income Urban Areas (Baseline 조사 결과를 이용한 페루 도시 빈곤지역 주민의 건강행태와 비만이 혈압에 미치는 영향)

  • Kim, Jae Woo;Nam, Eun Woo;Kim, Dohyeong;Yoon, Youngmin
    • The Journal of Korean Society for School & Community Health Education
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    • v.17 no.1
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    • pp.23-33
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    • 2016
  • Objectives: The purpose of this study is analysing the influence of how health behavior such as smoking, drinking, and consuming salt and obesity affects to blood pressure and providing useful data for preventing ischemic heart disease of Peru which is main cause of death since 2012 and promoting healthy lifestyle of community. Methods: At the selected four districts in Lima and Callao region of Peru by KOICA Peru office, survey was conducted among adults over the age of 18. Excepted 19 incomplete people for the missing, 686 people were analysed in this survey. Results: There was no significant relationship between blood pressure and drinking and salt intake. By regression analysis, systolic blood pressure was significantly related with gender, age and abdominal obesity and diastolic blood pressure was significantly related with gender and abdominal obesity. Conclusions: As a result, diastolic and systolic blood pressure are mainly affected by waist circumference and gender. Therefore, It's need to be classifying male into vulnerable groups in the occurrence of hypertension and providing health education and information about hypertension to them. For improving health status of vulnerable group, awareness of hypertension prevention and changing unhealthy lifestyle to healthy lifestyle activities are necessary. In the end, it is necessary to prevent abdominal obesity through periodic health education.

Electrical and Physical Properties of Sheath-core Type Conductive Textile Sensor with Home-Textile (Sheath-core 구조 전도사 섬유센서의 Home-Textile 적용을 위한 전기·물리학적 특성연구)

  • Cho, Kwang-Nyun;Jung, Hyun-Mi
    • Fashion & Textile Research Journal
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    • v.16 no.1
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    • pp.145-152
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    • 2014
  • The usage of textile-based sensors has increased due to their many advantages (compared to IT sensors) when applied to body assessment and comfort. Textile-based sensors have different detecting factors such as pressure, voltage, current and capacitance to investigate the characteristics. In this study, textile-based sensor fabrics with sheath-core type conductive yarns were produced and the relationship between capacitance changes and applied load was investigated. The physical and electric properties of textile-based sensor fabrics were also investigated under various laminating conditions. A textile based pressure sensor that uses a sheath-core conductive yarn to ensure the stability of the pressure sensor in the textile-based sensor (the physical structure of the reaction characteristic of the capacitance) is important for the stability of the initial value of the initial capacitance value outside the characteristic of the textile structural environment. In addition, a textile based sensor is displaced relative to the initial value of the capacitance change according to pressure changes in the capacitance value of the sensor due to the fineness of the high risk of noise generation. Changing the physical structure of the fabric through the sensor characteristic of the pressure sensor via the noise generating element of laminating (temperature, humidity, and static electricity) to cut off the voltage output element to improve the data reliability could be secured.

A Study on the Hermetic Method for Packaging of Implantable Medical Device (생체 이식형 의료기기의 패키징을 위한 완전 밀폐 방법에 관한 연구)

  • Park, Jae-Soon;Kim, Sung-Il;Kim, Eung-Bo;Kang, Young-Hwan;Cho, Sung-Hwan;Joung, Yeun-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.30 no.7
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    • pp.407-412
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    • 2017
  • This paper introduces a biocompatible packaging system for implantable medical device having a hermetic sealing, such that a perfect physical and chemical isolation between electronic medical system and human body (including tissue, body fluids, etc.) is obtained. The hermetic packaging includes an electronic MEMS pressure sensor, power charging system, and bluetooth communication system to wirelessly measure variation of capacitance. The packaging was acquired by Quartz direct bonding and $CO_2$ laser welding, with a size of width $ 6cm{\times}length\;10cm{\times}lheight\;3cm$. Hermetic sealing of the packaged system was tested by changing the pressure in a hermetic chamber using a precision pressure controller, from atmospheric to 900 mmHg. We found that the packaged system retained the same count or capacitance values with sensor 1 - 25,500, sensor 2 - 26,000, and sensor 3 - 20,800, at atmospheric as well as 900 mmHg pressure for 5 hours. This result shows that the packaging method has perfect hermetic sealing in any environment of the human body pressure.

Comparison of Muscle Activity of Thigh and Plantar Pressure according to the Change in Base of Support during Lunge (런지 시 기저면 변화에 따른 넙다리 근육의 근활성도와 족저압 비교 연구)

  • Lee, Jeon-Hyeong;Lee, Myoung-Hee;Kim, Gi-Chul
    • PNF and Movement
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    • v.15 no.3
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    • pp.343-351
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    • 2017
  • Purpose: This study aimed to suggest effective lunge exercise methods for various purposes by comparing differences in the muscle activity of thigh and plantar pressure according to changes in base of support during lunge exercises. Methods: The subjects were 20 college students who agreed to participate in the experiment. They performed three types of lunges-a basic lunge (BL), wide lunge (WL), and narrow lunge (NL). In a static position during each lunge, the muscle activity of the thigh and plantar pressure were measured. Each movement was maintained for 7 seconds, and the muscle activity for the 3 seconds in the middle was measured and analyzed. The plantar pressure was divided into six areas for analysis. The subjects randomly performed the lunges to prevent the influence of an experimental sequence. Each movement was performed three times, and the mean value of the three measurements was analyzed. Results: The analysis of muscle activities in the thigh during the three lunge movements showed statistically significantly higher muscle activity of biceps femoris in WL and NL than BL. Moreover, the analysis of plantar force showed statistically significant differences between BL and WL and WL and NL on the medial-forefoot and medial-midfoot, as well as between BL and WL and BL and NL on the lateral-midfoot. The analysis of plantar contact pressure exhibited statistically significant differences between BL and NL and WL and NL on the medial-forefoot, as well as a statistically significant difference between WL and NL on the medial-midfoot and lateral-hindfoot. Conclusion: This study suggests that changing the base of support during lunges can be useful to suit the purposes of various rehabilitation programs.

Effects of Several Factors on the Characteristics of Fe-Al Alloy Preform Manufactured by Reactive Sintering Process (반응소결법에 의해 제조된 Fe-Al합금 예비성형체의 특성에 미치는 제인자의 영향)

  • Joo, Hyung-Gon;Park, Sung-Hyuk;Joo, Sung-Min;Choi, Dap-Chun
    • Journal of Korea Foundry Society
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    • v.17 no.1
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    • pp.58-66
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    • 1997
  • The main aim of the present study is to investigate the effects of several processing parameters on the characteristics of Fe-Al alloy preform manufactured by reactive sintering process. The processing parameters include preform composition of 25, 40, 50, 60 and 75at.%Al, compacting pressure of 10, 20 and $30kg/cm^2$, and mean Al particle size of 29, 66 and $187{\mu}m$. Mean Fe particle size was $39{\mu}m$. The density of preform processed under same compacting pressure was not affected by changing Al composition. The preform with Al compositions of 25, 40, 50 and 60at.% Al swelled after reactive sintering process, thus having lower density than the green compacts. The preform with Al compositions of 75at.%Al, however, shrinked after reactive sintering process, thus having higher density than the green compacts. Ignition temperature increased with increasing compacting pressure, and increased with increasing Al composition at the fixed compacting pressure. And adiabatic temperature decreased with increasing compacting pressure at the fixed Al composition, and increased with increasing Al composition at the fixed compacting pressure. The size of compound particles increased with increasing Al composition. Especially, The size of compound particles increased largely in the case of 75at.%Al. It was observed that 50at.%Al preform have three dimentional network structure having a homogeneous and fine decreasing Al particle size.

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New calibration apparatus for a precise barometer (초정밀 기압계 교정을 위한 새로운 압력계 교정장치 개발)

  • 우삼용;이용재;최인묵;김부식;최종운
    • Journal of the Korean Vacuum Society
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    • v.12 no.3
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    • pp.157-161
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    • 2003
  • Nowadays there are increasing demands for more accurate measurement of atmospheric pressure according to the development of environmental industries. One of the most important pressure gauges for satisfying these demands is a quartz resonance barometer. In order to calibrate such an accurate barometer, laser/ultrasonic mercury manometers have been used. However, complexity and cost of mercury manometers made it out of use gradually. As a substitute, a gas-operated pressure balance is used for calibration of precise barometers. In such a case, commercially available pressure balances cannot be entirely suitable because consequent exposure of the piston, cylinder and masses to the atmosphere causes the problem of contamination. In this paper a device for changing the masses in situ without breaking the vacuum is described. This device made it possible to add or remove weights in the absolute mode, thereby greatly reducing the time between observations. At the same time, we investigated the characteristics of a commercial precise barometer using this new apparatus.

The Immediate Effects of Abdominal Pressure Belt on Pulmonary Function, Balance and Gait Ability in Stroke Patients (뇌졸중 환자에게 복부압박벨트 적용이 폐 기능, 균형 및 보행 능력에 미치는 즉각적인 영향)

  • Lim, Gyu-Ri;Go, Hyeon-Jeong;Kang, Ji-Hyun;Oh, Da-Wun;Park, Shin-Jun
    • Journal of Convergence for Information Technology
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    • v.10 no.2
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    • pp.176-183
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    • 2020
  • The purpose of this study was to determine whether abdominal pressure belt has an immediate effect on pulmonary function, balance and gait ability for stroke patients. Twenty subjects measured pulmonary function and the COP, BBS, TUG, 10m walk test, and FGA prior to belt wearing. Immediately all subjects were post-tested after wearing abdominal pressure belt of elastic components. Except for forced vital capacity (FVC) and forced experimental volume in the 1 second (FEV1), there were significant differences after belt wearing. This study suggests that the application of abdominal pressure belt enhanced balance and gait ability. However, improving pulmonary function requires several efforts, such as changing the pressure level, posture.

A Study on Performance Characteristics of Super-mirror Face Grinding Machine Using Variable Air Pressure (가변 공기압력 초경면 연마기의 성능 특성에 관한 연구)

  • Bae, Myung-Whan;Jung, Hwa
    • Transactions of the Korean Society of Automotive Engineers
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    • v.21 no.2
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    • pp.9-16
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    • 2013
  • The comparisons of performance characteristics between the super-mirror face grinding machine using variable air pressure developed in this laboratory to grind precisely the sliding face of a surface hardened workpiece with thermal spray and the conventional one are investigated by measuring the surface roughness and hardness for a SCM440. To process variously workpiece according to shape, size and materials, the rotating and contacting forces of the developed grinding machine can be changed by air pressure. The surface roughness of processed workpiece can be also attained to state of mirror face by grinding precisely the sliding face with changing the rotating speed of diamond wheel. It is possible to be attached to the various machine tools because the super-mirror face grinding machine using variable air pressure is a small size. The grinding efficiency is elevated because it can be worked by two or more grinding machines attached to concurrently a machine tool for the large workpiece. In this study, results show that the cusp height of the super-mirror face grinding machine for the particle size of 100 and $1500No./mm^2$ is lower than that of the conventional one because the vibration is reduced by rotating very fast the diamond wheel with a pressed air and it can be processed by rotating the diamond wheel with a constantly varied air pressure perpendicular to workpiece surface, and that the workpiece in the super-mirror face grinding machine for the particle size of $3000No./mm^2$ can be processed to state of mirror face that is rarely seen by the cusp height. It is also found that the surface hardness of both the conventional and the super-mirror face grinding machines are increased as the particle size of diamond wheel is reduced, and the surface hardness of the super-mirror face grinding machine is HRC 1.1 ~ 1.8 higher than that of the conventional one.