• 제목/요약/키워드: decrease

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자침이 뇌에 미치는 영향 (The Effect of Acupuncture on the Brain in Human)

  • 박경식
    • 대한예방한의학회지
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    • 제4권2호
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    • pp.214-234
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    • 2000
  • This study was carried to identify whether acupuncture of several acupuncture points can affect the brain and to observe which aspects appear in EEG mapping, using electroencephalography. Those results are as follows ; 1. The pattern of resting computerized EEG map in intact human is appered normal 2. Each Acupuncture in Kwan Weon or Jog Sam Ri meridian points bring about the increase in $\theta,\;\alpha-wave$ activity and at various area of the cerebrium and the decrease in $\delta,\;\beta-wave$ activity. It strands to reason that brain function is elevated On the other hand , synchronous acupuncture bring about the decrease of brain function in view of the decrease of $\delta,\;\theta-wave$ activity at frontal area, and the unstable brain state in view of the increase of $\beta-wave$ activity. 3. Acupuncture in Hyeon Jong meridian point bring about the increase of $\delta,\;\theta-wave$ activity at frontal area and $\beta-wave$ activity at temporal area. From these we deduce that brain function is declined and brain is unstable. Synchronous acupuncture with other meridian points reversly showed that brain function is elevated. 4. Synchronous acupuncture in Kwan Weon , Jog Sam Ri, Hyeon Jong bring about the decrease of the brain function and the unstable brain state, showing the pattern of increased $\delta,\;\theta-wave$ activity at frontal, parietal area, and increased $\beta-wave$ activity at temporal area.

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소결 밸브시트의 미세조직 및 기계적 성질에 미치는 볼밀 분말 혼합비의 영향 (Effects of Mixing Ratio of the Milled Powder on Microstructure and Mechanical Properties of Sintered Valve Seats)

  • 최성태;박종관;최창수;정인상
    • 한국분말재료학회지
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    • 제10권2호
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    • pp.89-96
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    • 2003
  • The recent trend of miniaturization and high performance of vehicle engines has put an urgent necessity for the development of valve seats which can operate under more severe conditions. In order to develope valve seat material that has the most excellent wear resistance at operating temperature of engine through improvement of the progress of work. the effects of mixing ratio of the milled powder on sintered and Cu-infiltrated properties of sintered valve seats have been studied. The resultant radial crushing strength and hardness of sintered specimens were gradually increased with increasement of volume of milled powders. It is because increasement of sintering density by increasing of surface diffusion. The hardness of Cu-infiltrated specimens became lower than that of the commercial powders as the increasement of volume of milled powders. It was due to the decrease of the amount of the martensite. By results of this research, It has been found that martensite is formed around of the Cu-infiltrated site and the decrease of the amount of the martensite is due to decrease of the amount of the Cu-infiltrated site by the decrease of gas channel.

온도변화에 따른 유리섬유/폴리우레탄 복합재료의 충격파괴거동 (A study on abrasive wear characteristics of side plate of FRP ship)

  • 김병탁;고성위
    • 수산해양기술연구
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    • 제45권3호
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    • pp.188-193
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    • 2009
  • The present study was undertaken to evaluate the effect of temperature on the results of Charpy impact test for glass fiber reinforced polyurethane(GF/PUR) composites. The Charpy impact test were conducted in the temperature range from -50$^{\circ}$ to 50$^{\circ}$. The impact fracture toughness of GF/PUR composites was considerably affected by temperature and it was shown that the maximum value was appeared at room temperature. It is believed that sensitivity of notch on impact fracture energy were increased with decrease in temperature of specimen. As the GF/PUR composites exposed in low temperature, impact fracture toughness of composites decreased gradually owing to the decrease of interface bonding strength caused by difference of thermal expansion coefficient between the glass fiber/polyurethane resin. And decrease of interface bonding strength of composites with decrease in specimen temperature was ascertained by SEM photographs of Charpy impact fracture surface.

A Potential Diagnostic Pitfall in the Differentiation of Hemorrhagic and Fatty Lesions Using Short Inversion Time Inversion Recovery: a Case Report

  • Kim, Jee Hye;Kang, Woo Young;Cho, Bum Sang;Yi, Kyung Sik
    • Investigative Magnetic Resonance Imaging
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    • 제20권3호
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    • pp.181-184
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    • 2016
  • Short inversion time inversion recovery (STIR) is widely used for spinal magnetic resonance imaging (MRI) because the pulse sequence of STIR is insensitive to magnetic field inhomogeneity and can be used to scan a large field of view. In this case report, we present a case of spinal epidural hematoma with unexpected signal decrease on a STIR image. The MRI showed an epidural mass that appeared with high signal intensity on both T1- and T2-weighted images. However, a signal decrease was encountered on the STIR image. This nonspecific decrease of signal in tissue with a short T1 relaxation time that is similar to that of fat (i.e., hemorrhage) could lead to a diagnostic pitfall; one could falsely diagnose this decrease of signal as fat instead of hemorrhage. Awareness of the nonselective signal suppression achieved with STIR pulse sequences may avert an erroneous diagnosis in image interpretation.

마른 오징어의 품질평가 및 보존기간 (Quality Evaluation and Shelf-life of Dried Squid)

  • 유병진;이강호
    • 한국수산과학회지
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    • 제21권3호
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    • pp.169-176
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    • 1988
  • In order to obtain the objective indices which can assess the quality and the shelf-life of dried squid, nonenzymatic browning, carbonyl value, trimethyl amine (TMA) and trimethyl amine oxide (TMAO) decrease and panel test were determined in dried squid at various water activity levels. When the data of nonenzymatic browning fit a zero order equation, $r^2$ value were more than 0.92 except aw 0.52 for 0.8241. Through variance analysis for the data of browning extent and TMAO decrease, the confidence limits of regression equation were $99\%$ and their limit values of shelf-life were shown 0.45390 O. D./g. solid and 190.322 g/g respectively. In case of TMAO, $r^2$ value was calculated more than 0.95. Linear regression equation for the correlation between browning data and average panel score was Y=0.6138-0.053X and its $r^2$ value was 0.9285. Also in TMAO decrease, the equation was InY=2.0314+0.08269x and $r^2$ value was 0.7854. The shelf-life, evaluated by nonenzymatic browning, TMAO decrease and panel test, was 110-170 days at aw 0.45-0.76 except aw 0.15.

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중년남성과 중년여성의 우울과 신체적, 사회·심리적, 인지적 요인 비교 (Comparison of Physical, Psychosocial and Cognitive Factors, and Depression between Middle-aged Women and Middle-aged Men)

  • 김희경
    • 성인간호학회지
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    • 제18권3호
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    • pp.446-456
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    • 2006
  • Purpose: The purpose of this study is to provide basic data for nursing programs in order to reduce depression among middle aged adults by looking at gender differences. Method: A comparative descriptive design was used. Subjects were 315 adults from February. 15 to March. 2, 2005, using a structured questionnaire. The data was analyzed using $\chi^{2}$-test, Pearson correlation analysis and stepwise multiple regression. Results: $\chi^{2}$-test revealed significant gender differences in socio-demographic variables for career, drinking, smoking, and satisfaction with the spouse. The factors that influenced depression for men were stress, fatigue, job satisfaction and self-efficacy. For women, those factors were stress, family support, coping skills, and well-being. Conclusions: The results show that gender differences existed in terms of depressions, in terms of factors influencing depression. As a result, when middle aged adults are provided nursing programs, gender differences should be considered. To decrease the depression of men, nursing interventions are needed to decrease their stress and fatigue, and to improve their job satisfaction and self- efficacy. To decrease the depression of women, it is also needed to decrease their stress, to elevate their family support and coping skills, and to support them so that their well-being is perceived good.

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송풍-역풍 겸용 축류팬 피치각에서 역풍시 효율저하 원인에 관한 연구 (A Study on the fan efficiency decrease on the backward flow in an axial fan)

  • 김화영;허진혁;문승재;이재헌;유호선;임윤철
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2009년도 하계학술발표대회 논문집
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    • pp.386-391
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    • 2009
  • In this study, the numerical study has carried out to analyze the factors of the efficiency decrease at backward flow situation in an axial fan with adjustable blades. The analysis is carried out the pitch angle $36^{\circ}$ on the forward flow and the pitch angle $-26^{\circ}$ on the backward flow. The numerical results show that the air flow rates of the pitch angle $36^{\circ}$ and $-26^{\circ}$ are respectively calculated to 285 CMM and 212 CMM. The results are similar to the experimental results carried out by Chang, and have made the maximum error of 10.6% when compared with the experimental results. The important reason of the fan efficiency decrease is that axial fan used for this study was designed to use for the forward flow. As the results, the pitch angle $-26^{\circ}$ has occurred the recirculation around the impeller blade, impeller cover and stator.

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Dehydration and pore swelling effects on the transfer of PEG through NF membranes

  • Escoda, Aurelie;Bouranene, Saliha;Fievet, Patrick;Deon, Sebastien;Szymczyk, Anthony
    • Membrane and Water Treatment
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    • 제4권2호
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    • pp.127-142
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    • 2013
  • In order to investigate the significance of "salting-out" and "pore swelling" effects on the nanofiltration of neutral solutes, rejection properties of two NF ceramic and polymeric membranes were studied with single polyethyleneglycol (PEG) solution and mixed PEG/inorganic electrolyte solutions. For both membranes, the rejection rate of PEG was found to decrease significantly in the presence of ions. In the case of the ceramic membrane (rigid pores), this phenomenon was imputed to the sole partial dehydration of PEG molecules induced by the surrounding ions. This assumption was confirmed by the lowering of the PEG rejection rates which followed the Hofmeister series. Experimental data were used to compute the resulting decrease in the Stokes radius of PEG molecules in the presence of the various salts. Concerning the polymeric membrane, the decrease in the rejection rate was found to be systematically higher than for the ceramic membrane. The additional decrease was then ascribed to the swelling of the pores. The experimental data of rejection rates were then used to compute the variation in the mean pore radius in the presence of the various salts. The pore swelling phenomenon due to accumulation of counterions inside pores was supported by electrokinetic charge density measurements.

송출공의 회전이 송출계수와 압력계수에 미치는 영향 (The Effect of Rotation of Discharge Hole on the Discharge Coefficient and Pressure Coefficient)

  • 하경표;구남희;고상근
    • 대한기계학회논문집B
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    • 제27권7호
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    • pp.948-955
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    • 2003
  • Pressure coefficient in rotating discharge hole was measured to gain insight into the influence of rotation to the discharge characteristics of rotating discharge hole. Pressure measurements were done by the telemetry system that had been developed by the authors. The telemetry system measures static pressure using piezoresistive pressure sensors. Pressure coefficients in rotating discharge hole were measured in longitudinal direction and circumferential direction with various rotating speed and 3 pressure ratios. From the results, the pressure coefficient, and therefore the discharge coefficient, is known to decrease with the increase of Ro number owing to the increase of flow approaching angle to the discharge hole inlet. However, there exists critical Ro number where the decrease rate of discharge coefficient with the increase of Ro number changes abruptly; flow separation occurs from the discharge hole exit at this critical Ro number. Critical Ro number increases with the increase of length-to-diameter ratio, but the increase is small where the length-to-diameter ratio is higher than 3. The decrease rate of discharge coefficient with the increase of Ro number depends on the pressure recovery at the discharge hole, and the rate is different from each length-to-diameter ratio; it has tendency that the short discharge hole shows higher decrease rate of discharge coefficient.

마이크로스피커 진동판의 등가탄성과 공명진동수의 연관성 (Relationship Between Geometrical Stiffness of Diaphragm and Resonance Frequency for Micro-speaker)

  • 오세진
    • 한국재료학회지
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    • 제20권12호
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    • pp.640-644
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    • 2010
  • Information technology devices, such as cellular phones, MP3s and so on, due to restrictions of space, require thin and small micro-speakers to generate sound. The reduction of the size of micro-speakers has resulted in the decrease of sound quality, due to such factors as frequency range and sound pressure level. In this study, the acoustical properties of oval microspeakers has been studied as a function of pattern shape on the diaphragm. The other conditions of micro-speakers, except for the pattern, was not changed. When the pattern is present on the diaphragm and the shape of pattern was a whirlwind, the resonance frequency was reduced due to the decrease of tensile strength of diaphragm. The patterns presented in the semi-minor axis of diaphragm did not effect a change of resonance frequency. However, increasing the number of patterns in the semimajor axis of diaphragm became a reason for the decrease of resonance frequency on edge side. When the depth of pattern on edge side was increased, the resonance frequency was decreased due to reduction of geometrical stiffness. If the height of edge and dome were increased, the resonance frequency and geometrical stiffness rapidly increased. After reaching the maximum values, they began to decrease with the continuous increase of height.