• Title/Summary/Keyword: cold test

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Sex Differences in Pain Threshold and Pain Tolerance and the Effects of Experimenter Gender on Pain Report (남녀별 및 실험자의 성별에 따른 동통역치와 동통내성의 차이)

  • Yun-Kyung Hur;Jae-Kap Choi
    • Journal of Oral Medicine and Pain
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    • v.20 no.1
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    • pp.97-103
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    • 1995
  • The purpose of this study was to evaluate the effect of experimenter gender on pain report as well as the sex differences in pain threshold and pain tolerance. Cold pressor test and pressure pain threshold (PPT) test were performed on forty dental students by both of a male and a female experimenter separately with 1 day interval. The obtained results were as follows : There were no differences in pain threshold and pain tolerance between males and females when they were examined by the same gender experimenter in the cold pressor test, but when they were examined by the opposite gender experimenter the pain threshold of males was significantly higher than females. When the pain threshold was measured by the same gender experimenter, using a algometer, there was no differences in PPT between males and females. However, when the same measurements were done by the opposite gender experimenter, the PPT of males was significantly higher than females at anterior temporalis and inferior masseter. For cold pressor test, females tended to report lower levels of pain threshold and pain tolerance to a male experimenter than a female, but the differences were not significant. Although both pain threshold and pain tolerance were increased when males were examined by a female experimenter in the cold pressor test, the statistical significance was found only in pain tolerance. When subjects were examined by the opposite gender experimenter in the PPT text, females reported significantly higher levels of pain at inferior masseter and males reported significantly lower levels of pain at anterior temporalis and inferior masseter.

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Rocket Engine Test Facility Improvement for Hot Firing Test of 75 ton-f Class Gas Generator and Cold Flow Test (75톤급 가스발생기 연소시험을 위한 시험장 개선 및 수류시험)

  • Kang, Dong-Hyuk;Lim, Byoung-Jik;Ahn, Kyu-Bok;Seo, Seong-Hyeon;Han, Yeoung-Min;Choi, Hwan-Seok
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.11a
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    • pp.29-33
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    • 2009
  • On the basis of the development experience of a gas generator for the 30 ton-f thrust liquid rocket engine combustor a Subscale Ground Firing Test Facility was designed and fabricated for a gas generator for the 75 ton-f thrust liquid rocket engine combustor. The Subscale Ground Firing Test Facility developed is going to be used to develop 75 ton-f class gas generator. Acquired data and test technique from this facility will be used to develope the high performance liquid rocket engine combustor and the Ground Firing Test Facility. This report describes the improved Subscale Ground Firing Test Facility for 75 ton-f class gas generator and results of the cold flow test.

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Research on a Respiratory Disease and Demand for Oriental Medical Cold Preventing Therapy in Chung-Buk (충북 일부지역 주민들의 호흡기 질환 및 한방 감기 예방 치료 수요에 관한 실태조사)

  • Yang, Su-Young;Hwang, Ji-Ho;Byun, Jun-Seop;An, Joung-Jo;Hong, Kweon-Eey;Park, Yang-Chun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.4
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    • pp.1045-1050
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    • 2007
  • This study was conducted to help oriental medical prevention program policy for improvement of public health in a local community. We have researched respiratory diseases and demands for oriental medical cold preventing therapy of some residents in Chung-Buk. We have conducted individually face-to-face interviews through standardized questionnaires to 141 residents of two towns (76 in Haeng-jung, 65 in Gu-mi) under the jurisdiction of Chung-won Public Health Center. The senior aged over 65 was 53.9%, which was a little more than the average senior age. The rate which could be diagnosed as a disorder of lung function was 2.97% by Lung Function Test. The participants diagnosed as Asthma accounted for 17.9% by Symptom Based Easy Asthma Diagnosis of Easy Asthma Management(EAM). The participants who had intentions of participating in oriental medical cold preventing therapy accounted for 58.6%. And among the oriental medical cold preventing therapy the preference for acupuncture and moxibustion was 77.1 %, which was much higher than any other thing. It is thought that people still have little understanding about the oriental medical cold preventing therapy. Therefore it is considered that the Korean government should try to establish well-organized cold preventing system on the basis of Oriental Medical theory for a local community.

Influence of Temperature Change of the Sole on Dynamic Balance Ability (발바닥의 온도 변화가 동적 균형능력에 미치는 영향)

  • Kim, Myungchul;Park, Mihye;Kim, Haein
    • Journal of The Korean Society of Integrative Medicine
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    • v.7 no.2
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    • pp.49-57
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    • 2019
  • Purpose: This study aimed to investigate the application of temperature to balance the training by observing the effect of sensory changes in the foot sole area on dynamic equilibrium ability through change in the sole temperature. Methods: Participants (n=49), who were selected as a certain standard, applied cold and hot packs for ten minutes at two-week intervals, and the laboratory's internal temperature was maintained at $25^{\circ}C$. The subjects were measured before and after the cold and hot applications in the stable condition with bare feet. Before each experiment applied the cold and hot packs, the balance ability of the ordinary temperature was measured once by conducting a limit of stability test using Biorescue, and the changes in balance ability were observed by measuring once after applying the temperature to the foot sole by means of the ice pack and the hot pack. Results: The results of the dynamic balance test, both before and after the temperature application, were compared, and it was confirmed that the moving area before and after cold application decreased significantly, and the moving area before and after application was not significantly different. The mean of pre-post area differences was found to have decreased at a statistically significant rate in the forward, backward, rightward, leftward, and total areas for the group that received the cold application compared to the group that received the hot application. Conclusion: These findings showed that cold application to the foot sole decreased dynamic balance. There was no significant difference in the dynamic balance ability both before and after the hot application to the foot sole, so it is difficult to conclude that the hot application affected dynamic balance.

An Effect of Cold Environment on Human's Physiological Responses and Task Performances (저온 작업환경이 인간의 생리적 반응 및 작업 수행도에 미치는 영향)

  • Ku, Hak-Keun;Kwak, Hyo-Yean
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.5
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    • pp.622-629
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    • 2007
  • Some worker is occupationally exposed to cold and freezing environment. The cold stimuli in the working environment impose physiological and psychological loads on workers to decrease the task performance. The purpose of this study is to investigate the cold stimuli of cold and freezing stores widely used in Busan can make an effect on human's physiological responses and task performance, experimentally and analytically. In the experiment, 5 workers are selected as subjects, and then their skin temperatures of hand and ear, heart rates, blood pressure, and ring test performances in cold($3^{\circ}C$) and freezing($-22^{\circ}C$) stores were measured for 21 minutes and analyzed by using statistical method. It is observed that a physiological variation and the task performance are significantly influenced by an exposure time as well as a strength of cold stimuli. Also, it is suggested the exposure limiting times for the useful manual work and the performance predict model of the ring tasks. The result of this study will be useful for a fundamental data of which design the standard task time of manual tasks and solve the job placement problem of worker selection and placement in cold environment.

A Study of Design of $H_2O_2$/Kerosene Ignition Injector and Spray Characteristics (과산화수소/케로신 점화용 분사기 설계 및 분무특성에 관한 연구)

  • Kim, Bo-Yeon;Hwang, Oh-Sik;Lee, Yang-Suk;Ko, Young-Seong;Kim, Yoo;Kim, Sun-Jin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.05a
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    • pp.37-40
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    • 2009
  • This study was performed to design of $H_2O_2$/Kerosene catalyst ignition injector and cold flow test to measure the mass flow rate and spray angle. Mass flow rate and spray angle were measured by designed injector through cold flow test. Result of test kerosene mass flow rate was measured 12.88 g/s and 40 deg of spray angle at pressure drop 3 bar as same as design point. And hydrogen peroxide was measured 94.39 g/s at pressure drop 1 bar smaller than design point.

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A study on steady state performance of variable thrust nozzle by cold-flow test (공압시험을 이용한 추력가변 노즐의 정상상태 성능 연구)

  • Kim, Jung-Keun;Lee, Ji-Hyung;Oh, Jong-Yun;Chang, Hong-Been;Kim, Shin-Hoe
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2007.04a
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    • pp.289-294
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    • 2007
  • Solid Rocket Motor(SRM) has advantages such as - high specific impulse, operational safety and simplicity in design and manufacturing process, but thrust magnitude can't be controlled. For studying of pintle nozzle that can control the thrust magnitude of SRM, cold flow test and numerical analysis about needle type pintle shape were performed and results were presented in this paper. As the results of this study, pintle tip's shape and nozzle contour were important design parameters because thrust performance and variable thrust range of pintle nozzle depend on them. Especially, the thrust of needle typed pintle nozzle adopted in this test was predicted 13% higher than normal nozzle without pintle.

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Development of LPI Vehicle Fuel Filter Housing (LPI 차량용 연료필터하우징 개발)

  • Hong, Byeong-Hoon;Park, Sung-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.653-659
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    • 2014
  • Computer simulation has been performed to optimize cold forging process of automotive LPI fuel filter housing. A mold and the test product have been manufactured considering the strain and load distribution during the cold forging process. Also, fuel flow simulation has been performed to analyze flow characteristics of existing model and new model. Simulation result shows that two models have equivalent pressure drop. Compared with the mass of existing product, raw material reduction of 16 g and 30.5 g has been achieved from the upper and lower housing, respectively. Total mass reduction of the new housing was 46.5 g. Leak test and internal pressure test have been performed to verify the safety standard and test results were satisfactory.

Effects of Cryogenic Temperature on Wear Behavior of 22MnB5 Under Cold Stamping (극저온이 22MnB5강의 냉간 스탬핑 마모에 미치는 영향)

  • Ji, Min-Ki;Noh, Yeonju;Kang, Hyun-Hak;Jun, Tea-Sung
    • Tribology and Lubricants
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    • v.38 no.6
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    • pp.241-246
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    • 2022
  • This paper presents the effects of cryogenic temperature on the wear behavior of 22MnB5 blank under cold stamping. After immersing the blank in liquid nitrogen (LN2) for 10 min, a strip drawing test was performed within 10 s. The hardness was measured using the Rockwell hardness test, which increased from 165 HV at 20℃ to 192 HV at cryogenic temperature. The strip drawing test with 22MnB5 blank and SKD61 tool steel shows that for the different wear mechanisms on the tool surface with respect to temperature; adhesive wear is dominant at 20℃, but abrasive wear is the main mechanism at cryogenic temperature. As the friction test is repeated, sticking gradually increases on the tool surface at 20℃, whereas the scratch increases at cryogenic temperature. For the friction behavior, the friction coefficient rapidly increases when adhesive wear occurs, and it occurs more frequently at 20℃. The results for nanoindentation near the worn blank surface indicate a difference of 1.3 GPa at 20℃ and 0.8 GPa at cryogenic temperature compared to the existing hardness, indicating increased deformation by friction at 20℃. This occurs because thermally activated energy available to move the dislocation decreases with decreasing temperature.

Construction and Quality Control Example of Cold Weather Concreting in Field (현장에서의 한중콘크리트의 시공 및 품질관리 사례)

  • Park, Jong-Gun
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2001.10a
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    • pp.171-175
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    • 2001
  • The quality control application of concrete are one of the most important problems to be considered in cold weather concreting. And, the construction is going on now Therefor, the major test variables are compressive strength of concrete, curing method and volume of air content. This shown to be possible to construction and quality control of cold weather concreting in field.

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