• Title/Summary/Keyword: 진동량

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The Study about Improvement of Neuro Energy Decreased by Energy Saving (에너지절감에 의해 감소되는 뉴로에너지의 증강에 관한 연구)

  • Kim, Myung-Ho;Kang, Dong-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.715-721
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    • 2018
  • This study examined energy saving and elevating the worker's neuro energy (comfort, concentration, physical, and psychological stability) by compensating for the unpleasant tactile sensation to stimulate auditory and olfactory senses and reduce energy consumption. The experiment was conducted in an environment test room under the test conditions of temperature $25[^{\circ}C]$, relative humidity 50[RH%], illumination 1,000[lux] and air current speed 0.02[m/sec] by stimulating the auditory senses with a 1/f change in rhythm and the olfactory senses with an aroma scent. The experiment utilized the method of EEG, which evaluates human body's psychological status via tactile means, and the method of the vibra image, which evaluates the learning abilities, HRV and human body's psychological status via non-tactile means. The subjects were selected as eight university students (four males and four females) in their 20s, the type that have high relative ${\alpha}$(8~13[Hz]) activation in occipital lobe, which brings the highest level of mind stability and concentration, who had no difficulty in physical activities. The subjects' posture and physical activity was fixed to 1met - when the subjects are seated and relaxing in a comfortable environment - and their clothes condition was standardized as 0.7clo. As a result, the sentimental and psychological stability and concentration were the highest in the multisensory stimulation of jasmine scent and change rhythm of an a=1.106 sound source. In addition, under this condition, the relative $M{\alpha}$ and relative $M{\beta}$ increased by 70.49[%] and 89.72[%], respectively; the HRT decreased by 39.09[%]; and the fatigue and tension/anxiety decreased by 36.85[%] and 15.54[%], respectively.

Magnesium for automotive applications (마그네슘 자동차 부품의 활용현황과 전망)

  • 금동화;김혜성;박상인
    • Journal of the korean Society of Automotive Engineers
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    • v.18 no.5
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    • pp.53-68
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    • 1996
  • 마그네슘이 자동차 경량화에 관심이 되는 이유는 근본적으로 CAFE 규제와 같이 경량화를 통한 화석연료의 소모를 크게 억제해야 한다는 사회적인 규제이나, 지난 10여년간의 기술발전으로 내식성이 나쁘다거나 취급이 위험한 금속이라는 인식이 크게 개선된 데에도 있다. 다른 경량금속에 대한 Mg 지금 가격의 비교조건이 호전되었고 향후 원소 재공급의 다변화가 추진되고 있는 것도 환경을 변화시킨 중요한 요인이다. 그간 중요한 경량화 대체 재료로 연구투자가 많았던 유기고분자 재료 및 FRP 등과 같은 복합재료는 폐기부품의 재활용이 어려움 때문에 호나경친화적인 단점이 부각되어, 이 소재의 증가가 주춤해 있다. 마그네슘의 경우에는 재활용이 가능하고, 진동흡수효과가 매우 커서 소음발생을 크게 줄일 뿐만 아니라, 주행 및 내구성시험에서 치수안정성이 좋고 많은 종류의 전자기기 사용에 의한 전자파 차폐효과도 큰 장점을 가지고 있다. 본 고에서는 Mg 다이캐스팅으로 자동차부품의 경량화 현황과 선진국에서 보는 전망을 미국을 중심으로 정리하고, 이와 관련한 Mg 다이캐스팅으로 자동차부품의 경량화 현황과 선진국에서 보는 전망을 미국을 중심으로 정리하고, 이와 관련한 Mg 기술적인 이슈와 시장전망도 서술하였다. 그리고 현재 우리나라의 연구계와 부품업계에서 추진하고 있는 연구개발 동향을 자동차 업계에 소개하는 의미도 있다. 이처럼 우리나라의 현황을 정리해 보는 것은 국내 자동차 산업이 국제적인 경쟁을 하고 있고 Mg기술과 원료확보에서 일본의 견제를 받고 있는 우리의 현실에서도 필요한 작업으로 생각된다.값들로 구성되는 형상을 내구 성능, 성형성등을 고려하여 최종 형상으로 결정한다. 내구성능의 예측은 금속부품의 내구수명 예측에 널리 이용되고 있는 방법이 방진 고무부품의 경우에도 적용 가능한지를 검토하고, 방진 고무부품에도 일반적으로 적용될수 있는 내구수명 예측방안의 개발 가능성을 타진해 보았다. 본 연구의 목표는 시제품을 제작하기 이전에 설계된 부품에 대한 스프링 상수 및 내구특성을 체계적으로 규명하여 제품 시험의 횟수를 줄이고, 보다 정밀한 제품을 제작할 수 있도록 하기 위한 것이다.세포수는 초기 배반포기배에서 팽윤 배반포기배로 진행됨에 따라 두배에서 세배 정도 증가되었음을 알 수 있었다. 또한, differential labelling과 bisbenzimide기법에서 얻어진 각각의 총세포수를 비교하였을 때 총세포수는 발달의 진행 정도에 따라 증가되며 그와 동시에 동일한 군 간의 세포수도 거의 유사함을 알 수 있었다. 따라서, ICM과 TE를 differential labelling하는 기법은 수정란의 quality를 평가하는데 매우 유용한 기법으로서 착상전 embryo 발달을 연구하는데 효과적으로 이용될 수 있다는 것을 시사한다. 고도의 유의차를 나타낸 반면 비수구, 초생수로구 및 Bromegrass 목초구 간에는 아무런 유의차가 인정되지 않았다. 7. 농지보전 처리구인 배수구와 초생수로구는 비처리구에 비해 낮은 침두 유출량과 낮은 토양유실량을 나타내었다.구보다 14% 절감되는 것으로 나타났다.작용하는 것으로 사료된다.된다.정량 분석한 결과이다. 시편의 조성은 33.6 at%

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The Seasonal and Regional Distribution of Phytoplankton Communities in the Fisheries Resources Protection Area of Korea in 2016 (2016년 한국 수산자원보호해역에서 식물플랑크톤 군집의 계절 및 해역별 분포)

  • Yoo, Man Ho;Park, Kyung Woo;Oh, Hyun Ju;Koo, Jun Ho;Kwon, Jung No;Youn, Seok Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.2
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    • pp.288-293
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    • 2018
  • This study was conducted to understand the characteristics of the seasonal and regional distribution of phytoplankton communities in the Fisheries Resources Protection Area of Korea (FRPA). We investigated the phytoplankton composition, abundance and dominant species collected from five different regions (Cheonsu, Tongyeong-I, Tongyeong-II, Hansan, and Jindong) in 2016. According to the results, most environmental parameters, such as temperature, salinity and nutrients, showed statistically significant seasonal differences. Suspended particulate material (SPM) only showed a statistically significant regional difference. The mean abundance of phytoplankton ranged from 13 to $4,062cells{\cdot}ml^{-1}$, with large spatio-temporal fluctuations. In particular, the bloom of phytoplankton (>$10^3cells{\cdot}ml^{-1}$) in Cheonsu Bay occurred in April and October with Skeletonema spp. and Chaetoceros socialis being the dominant species during these two seasons, respectively. The dominant species in the FRPA were diatoms (Pseudo-nitzschia spp., Skeletonema spp., and Chaetoceros pseudocriniuts) and dinoflagellates (Scrippsiella trochoidea and Tripos furca). The seasonal distribution of phytoplankton communities showed typical characteristics of coastal waters, i.e., that diatoms usually dominated in winter and autumn, while dinoflagellates tended to dominate in spring and summer. Meanwhile, the dominance rate of diatoms in the phytoplankton community in Cheonsu Bay, which is located in a high-turbidity region, was 9~27 % greater than that of diatoms in the phytoplankton community found in the south coastal waters, which is a low turbidity region.

Engineering Properties of Concrete with Rice-Straw Ash (볏짚재를 혼입(混入)한 콘크리트의 공학적(工學的) 성질(性質))

  • Sun, Chan Yong;Lee, Hee Man;Kim, Young Ik;Kim, Kyung Tae;Seo, Dae Seuk;Nam, Ki Sung
    • Korean Journal of Agricultural Science
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    • v.25 no.2
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    • pp.285-292
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    • 1998
  • This study was performed to evaluate the engineering properties of concrete using normal portland cement, natural aggregates and rice-straw ash. The following conclusions were drawn; 1. The unit weight was in the range of $2,250{\sim}2,335kgf/m^3$, the weights of those concrete were decreased 1~5% than that of the normal cement concrete, respectively. 2. The highest strength was achieved by 5% rice-straw ash filled rice-straw ash concrete, it was increased 17% by compressive strength, 30% by tensile strength and 21% by bending strength than that of the normal cement concrete, respectively. 3. The ultrasonic pulse velocity was in the range of 4,059~4,360m/s, which was showed about the same compared to that of the normal cement concrete. The highest ultrasonic pulse velocity was showed by 5% rice-straw ash filled rice-straw ash concrete. 4. The acid-proof was increased with increase of the content of rice-straw ash. The acid-proof was increased 1.15 times by 5% rice straw ash, 1.45 times by 10%, 1.6 times by 15% rice-straw ash filled concrete than that of the normal cement concrete, respectively.

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Pattern Making Method and Design of Power Shoulder Jackets (파워 숄더 재킷의 디자인 및 패턴전개 방법)

  • Park, Sanghee;Lee, Eunhae
    • The Journal of the Korea Contents Association
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    • v.13 no.7
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    • pp.131-140
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    • 2013
  • Power shoulder look is most noticeable trend in women's wear in the 09/10 season. Specially jackets with sharper angle and wider shoulder became the best item since then, and were chosen for must-have item by fashion directors. Jacket occupied 50% in power shoulder items. Its shoulder angle was from 0 to 30 degree but items with 15 degree stood out among them. There are three methods to make power shoulder look jackets; shoulder extension method with moving shoulder tip up and sleeve cap height, method of extension and cutting sleeve cap with shorten shoulder length, and method of extension and moving shoulder tip up in the sleeve with shoulder line like raglan sleeve. As a result, shoulder angle is higher, starting point of shoulder line is closer to side neck point and shoulder point is extender to outside for appearance and fit. In shoulder extension method, the arm hole line was drawn with care by matching joining shoulder seam and setting the sleeve into the arm hole. In sleeve cap transformation, it is desired that starting point shoulder angle is moved closely to side neck point. In case of the sleeve with shoulder line, it needs to consider enough ease of shoulder and upper arm. For making patterns of power shoulder look jacket, it need to consider arm hole line, shoulder length, shoulder point position, sleeve cap height and sleeve width with interpretation design facts. In this study, through the analysis clothing construction method of power shoulder jacket, it is of help to pattern making for various power shoulder design items.

Feed System Modeling of Railroad using Fuel Cell Power Generation System (연료전지 발전시스템을 이용한 철도급전계통 모델링)

  • Yoon, Yongho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.4
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    • pp.195-200
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    • 2020
  • With the growing interest in fossil fuel depletion and environmental pollution, railroad cars operating in Korea are in progress as the conversion from diesel to electric vehicles expands. The photovoltaic system, which is applied as an example of the conversion of electric vehicles, is infinite and pollution-free, and can produce energy without generating hazards such as air pollution, noise, heat, and vibration, and maintain fuel transportation and power generation facilities. There is an advantage that is rarely needed. However, the amount of electricity produced depends on the amount of solar radiation by region, and the energy density is low due to the power generation of about 25㎡/ kWp, so a large installation area is required and the installation place has limited problems. In view of these problems, many studies have been applied to fuel cells in the railway field. In particular, the plan to link the fuel cell power generation system railroad power supply system must be linked to the power supply system that supplies power to the railroad, unlike solar and wind power. Therefore, it has a close relationship with railroad cars and the linkage method can vary greatly depending on the system topology. Therefore, in this paper, we study the validity through simulation modeling related to linkage analysis according to system topology.

Organotitanium Chemistry (IV). The Molecular and Electronic Structure of $TiCl(OC_6H_5)_3{\cdot}C_6H_5OH\;and\;Ti(OC_6H_5)_4{\cdot}C_6H_5OH$ (유기티탄 화학 (제4보). $TiCl(OC_6H_5)_3{\cdot}C_6H_5OH\;및\;Ti(OC_6H_5)_4{\cdot}C_6H_5OH$의 분자 및 전자구조)

  • Lee Hoosung;Uh Young Sun;Sohn Youn Soo
    • Journal of the Korean Chemical Society
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    • v.19 no.2
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    • pp.92-97
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    • 1975
  • The molecular and electronic structures of $TiCl(OC_6H_5)_3{\cdot}C_6H_5OH\;and\;Ti(OC_6H_5)_4{\cdot}C_6H_5OH$ have been studied by employing cryoscopic and electronic spectroscopic methods. The cryoscopic data have shown that the dimeric tetraphenoxytitanium(Ⅳ) phenolate in solid undergoes complete dissociation into monomer in solution and also the chlorocomplex starts dissociation around the concentration of 8 m mole/l. Therefore, these two Ti-complexes are pentacoordinated in dilute solution and the local symmetry of the titanium ion in these complexes seems to be trigonalbipyramid. The electronic spectra of $TiCl(OC_6H_5)_3{\cdot}C_6H_5OH$ and $Ti(OC_6H_5)_4{\cdot}C_6H_5OH$ each show two band, systems, one vibration-structural band characteristic of the aromatic ring in the near UV and another visible band at 26.8 kK, 29.6 kK, respectively, which are assigned as a ligand to metal charge transfer band corresponding to $^1A_1''{\to}^1E'\;or\;^1E''$ transition.

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Measurement of the Skin Blood Flow using Cross-Correlation (Cross-Correlation법에 의한 피부 혈류속도 측정)

  • Lee, Jeong-Taek;Im, Chun-Seong;Ryu, Jeom-Su;Lee, Jong-Su;Gong, Seong-Bae;Kim, Yeong-Gil
    • Journal of Biomedical Engineering Research
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    • v.19 no.4
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    • pp.379-384
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    • 1998
  • To measure precisely the blood velocity in the skin microcirculation, we have used time domain correlation (called Cross-Correlation) based on the processing of the backscattered RF signal obtained with a wideband echographic imaging transducer, although it is difficulties of adaptation of the pulsed wave system, because of the data processing in real time and the hardware problem. This dedicated technology based on a 20MHz echographic imaging system has been developed. We present how the experimental data, i.e. the backscattered RF signal, have to be analyzed. After RF lines realignment, stationary echo canceling procedure and correlation level control, a velocity profile has been obtained. In-vitro result show that velocity measurements as low as 0.1mm/sec attainable with a 80${\mu}m$ in axial resolution. We have also validated with in-vivo experimentation on the external ear of a rabbit using B-mode sector scanning image and M-mode image of a custom made 20MHz skin image system. The flow of the "auriculares caudales" vein, a microvessel of 600 m diameter, has been detected and studied. This technique will allow a more precise exploration of circulatory troubles in cutaneous pathologies.

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Comparative Analysis of Focal Length Bias for Three Different Line Scanners (초점거리 편의가 지상 정확도에 미치는 영향 비교 연구 - 세가지 라인 스캐너를 대상으로 -)

  • Kim, Changjae
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.4_1
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    • pp.363-371
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    • 2014
  • Most space-borne optical scanning systems adopt linear arrayconfigurations. The well-knownthree different types of space-borne sensors arealong-track line scanner, across-track linescanner, and three line scanner. To acquire accurate location information of an object on the ground withthose sensors, the exterior and interior orientation parameters are critical factors for both of space-borne and airborne missions. Since the imaging geometry of sensors mightchange time to time due to thermal influence, vibration, and wind, it is very important to analyze the Interior Orientation Parameters (IOP) effects on the ground. The experiments based on synthetic datasets arecarried out while the focal length biases are changing. Also, both high and low altitudes of the imagingsensor were applied. In case with the along-track line scanner, the focal length bias caused errors along the scanline direction. In the other case with the across-track one, the focal length bias caused errors alongthe scan line and vertical directions. Lastly, vertical errors were observed in the case ofthree-line scanner. Those results from this study will be able to provide the guideline for developing new linearsensors, so as for improving the accuracy of laboratory or in-flight sensor calibrations.

Illuminance Effects Affecting to Cognitive Ability of the Elderly (고령자의 인지력에 미치는 조도의 영향)

  • Kim, Myung-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.3
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    • pp.507-512
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    • 2019
  • To study how illuminance affects cognitive ability of the elderly, the elderly's EEG, concentration, HRV and vibra image were measured in a test room with temperature $25[^{\circ}C]$, relative humidity 50[RH%] and air flow speed 0.02[m/sec] by varying illuminance to 100[lux], 300[lux], 600[lux], 1000[lux] and 1500[lux]. Ten active elderly males were selected as subjects. Experiment condition was fixed as 1met of activity amount where the subject is seated and relaxed with cloth amount of 0.7clo. As a result, 1000[lux] was found out to be the most pleasant illuminance for the elderly, because $M{\beta}$ increased by 66.35%, and $S{\alpha}$ increased by 31.57% when the elderly was under 1000[lux] of illuminance. Also, concentration under 1000[lux] increased by 8.83% compared to 100[lux], and the pattern of concentration maintained uniformly. SDNN increased by 74.94% under 1000[lux] compared to 100[lux]. Nervousness decreased by 97.23% under 1000[lux] compared to 100[lux]. Moreover, HRT notably increased and aggression remarkably decreased under illuminance of 1000[lux]. Thus, based on the fact that comfort, concentration and heart stability of the elderly reach the highest under 1000[lux], it is determined that the illuminance has to be considered foremost in designing the elderly's welfare facilities to raise their safety and level of independence.