• 제목/요약/키워드: CM Trend

검색결과 420건 처리시간 0.027초

어류의 주광성에 관한 연구 (2) - 백색광에 대한 돌돔과 복섬의 반응 - (Phototaxis of Fish (2) - Response of Rook bream and Grass puffer to the white lights -)

  • 양용림
    • 수산해양기술연구
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    • 제16권1호
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    • pp.27-35
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    • 1980
  • 빛에 대한 어류의 행동을 조사하기 위항 돌돔 Oplegnathus fasciatus 과 복섬 Fugu niphobles 에 빛의 세기가 서로 다른 여섯가지 백색인공광원으로 광을 주어, 그에 대한 반응을 주야에 각각 조사한 결과는 다음과 같다. 1. 제한된 실험수내에서의 광에 대한 구간별분포는 두 어종이 모두 구간에 많이 모여 분포은 대체로 U자형이되었다. 2. 돌돔은 수중도가 어떤값보다 높아지거나 낮아지면 광원쪽에 더 많이 모이는 경향을 보였으며, 주야간에 비슷하였다. 복섬은 수중도가 어떤 값보다 높아지거나 낮아지면 광원에서 멀리 떨어지는 경향을 보였으며 주야간에 다소의 차이가 있었다. 3.집어솔이 최대가 되는 평균수중조도(적정조도)는 돌돔이 162.0 lux (104.3-238.1 lux)로서 주야간에 같았으며, 복섬은 주간에 16.6 lux (10.6-24.5 lux), 야간에 1.9 lux (1.2-2.9 lux)로서 주간에 더 높았다. 4. 조명시간에 따른 집어솔은 돌돔의 경우 점등후 시간이 경과함에 따라 증가하는 경향을 보였으며, 야간보다 주간에 그 변화가 심했다. 복섬은 시간이 경과함에 따라 완만하게 증가하였으며, 야간보다 주간에 그 변화가 다소 심했다.

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발파진동의 크기가 양생콘크리트의 강도와 물성에 미치는 영향 (Effects of Blasting Vibrations on Strength and Physical Properties of Curing Concrete)

  • 박근순
    • 화약ㆍ발파
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    • 제16권4호
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    • pp.18-28
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    • 1998
  • Effects of blasting vibrations on curing concrete have not been well studied. As a result, unreasonable and strong blasting vibration constraints have been placed on blasting when it occur in the vicinity of curing concrete. To study the effects of blasting on curing concrete blocks of $33.3{\times}27.7{\times}16.2cm$ were molded and placed on the quarry. Several sets of concrete blocks were subjected separately to peak vibrations of 0.25, 0.5, 1.0, 5.0 and 10cm/sec. The impulses of blasting vibrations were applied with thirty-minute intervals. Along with unvibrated concrete blocks, the vibrated concrete samples cored with 60.3mm in diameter were measured for elastic moduli, sonic velocity and uniaxial compressive strength. Test results can be summarized as follows; 1. The blasting vibrations between 6 and 8 hours after pour generally lowered on the uniaxial compressive strength of the concrete. 2. A low blasting vibration of 0.25cm/sec did not affect the uniaxial compressive strength. As the magnitude of the blasting vibration increases, compressive strength of concrete is decreased. 3. Physical properties of the P-wave velocity, Young’s modulus, and Poisson's ratio showed a weakly decreasing trend in the concrete blocks vibrated between 6 and 8 hours after pour.

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제주도 양식넙치, Paralichthys olivaceus의 스쿠티카충병 발생 동향 (Scuticociliatusis in Flounder Farms of Jeju Island)

  • 진창남;이창훈;오상필;정용욱
    • 한국어병학회지
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    • 제16권2호
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    • pp.135-138
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    • 2003
  • The research was carried out to know the occurrence trend of scuticociliatosis and mortality of fingerlings in flounder. The diseased fish were collected from on-land rearing farms lind hatcheries of flounder in Jeju Island from January 1991 to December 2001. Occurrence of scuticociliatosis was about 10% of total occurred diseases from 1991 to 1996, but increased to 34.5% in 2001. Although monthly occurrence of scuticociliatosis was not related to season from 1999 to 2001, the highest occurrence was revealed in July and August. Mixed infections of bacteria including Vibrio sp. Edwardsiella tarda, Streptococcus sp., and Flexibacter sp. with scuticociliates were observed. Among the bacteria, Vibrio sp. was the highest frequency(40.1%), and the lowest one(10.1%) was Streptococcus sp., Mortality of fingerlings by scuticociliates was different sharply according to size of fish. Mortality of infected fingerlings below 7 cm of total length was 53.8%, while that of normal fingerling above 7 cm of total length was 13.2%. When fish were grown above 25 cm, mass mortality by scuticociliates infection was decreased markedly.

발파진동의 크기가 양생콘크리트의 강도와 물성에 미치는 영향 (Effects of Blasting Vibrations on Strength and Physical Properties of Curing Concrete)

  • 임한욱;박근순;정동호;이상은
    • 터널과지하공간
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    • 제5권2호
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    • pp.134-143
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    • 1995
  • Effects of blasting vibrations on curing concrete have not been well studied. As a result, unreasonable and strong blasting vibration constraints have been placed on blasting when it occurs in the vicinity of curing concrete. To study the effects of blasting on curing concrete blocks of 33.3X27.7X16.2 cm were molded and placed on the quarry. Several sets of concrete blocks were subjected separately to peak vibrations of 0.25, 0.5. 1.0, 5.0, and 10cm/sec. The impulses of blasting vibrations were applied with thirty-minute intervals. Along with unvibrated concrete blocks, the vibrated concrete samples cored with 60.3 mm in diameter were measured for elastic moduli, sonic velocity and uniaxial compressive strength. Test results can be summarized as follows; 1. The blasting vibrations between 6 and 8 hours after pour generally lowered on the uniaxial compressive strength of the concrete. 2. A low blasting vibration of 0.25 cm/sec did not affect the uniaxial compressive strength. As the magnitude of the blasting vibration increases, compressive strength of concrete is decreased. 3. Physical properties of the P-wave velocity, Young's modulus, and Poisson's ratio showed a weakly decreasing trend in the concrete blocks vibrated between 6 and 8 hours after pour.

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ICR 마우스의 태아(胎兒)에 대(對)한 방사선(放射線)과 초음파(超音波)의 공동효과(共同效果)에 관한 실험적(實驗的) 검토(檢討) (Combined Effects of Radiation and Ultrasound on Embryonic Development in Mice)

  • 구연화
    • 대한방사선기술학회지:방사선기술과학
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    • 제14권2호
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    • pp.37-44
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    • 1991
  • The combined effect of radiation and ultrasound has been studied in mouse embryos. Radiation and/or ultrasound were adminstered to ICR mice on day 8 of gestation. Intrauterine death, gross malformation, and fetal body weight were selected as indicators of effects. Does of whole-body ${\gamma}-irradiation$ were 0.5 to 2.5 Gy and those of ultrasound were $0.5\;W/cm^2$ to $3\;W/cm^2$. Intrautrine mortality increased with increasing radiation dose ; this trend was more remarkable in combination with ultrasound. Gross malformations such as exencephaly and anophthalmia/microphthalmia appeared frequently in the fetuses treated with both radiation and ultrasound. Decreased fetal weight was observed even in mice treated with 1.5 Gy of radiation or $1\;W/cm^2$ of ultrasound. There was a linear relationship between dose and reduction of fetal weight. The fetal weight was sensitive, precise and easy-to-handle indicator for the effects of growth retardation. Intrauterine mortality and frequencies of exencephaly and anophthalmia/microphthalmia were higher than the sum of those induced by radiation and by ultrasound. The results indicatied that the combined action of radiation and ultrasound on intrauterine death and malformations was synergistic.

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자기센서용 Ni-PZT-Ni, Co, Fe 적층구조 소자의 ME 특성 (Magnetoelectric Characteristics on Layered Ni-PZT-Ni, Co, Fe Composites for Magnetic Field Sensor)

  • 류지구;전성즙
    • 한국전기전자재료학회논문지
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    • 제28권2호
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    • pp.92-98
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    • 2015
  • The magnetoelectric characteristics on layered Ni-PZT-Ni, Co, Fe composites by epoxy bonding for magnetic field sensor were investigated in the low-frequency range. The ME coefficient of Ni-PZT-Ni, Ni-PZT-Co and Ni-PZT-Fe composites reaches a maximum of $200mV/cm{\cdot}Oe$ at $H_{dc}=110$ Oe, $106mV/cm{\cdot}Oe$ at $H_{dc}=90$ Oe and $87mV/cm{\cdot}Oe$ at $H_{dc}=160$ Oe, respectively. A trend of ME charateristics on Ni-PZT-Co, Ni-PZT-Fe composites was similar to that of Ni-PZT-Ni composites. The ME output voltage shows linearly proportional to ac field $H_{ac}$ and is about 0~150 mV at $H_{ac}$=0~7 Oe and f=110 Hz in the typical Ni-PZT-Ni sample. The frequency shift effect due to the load resistance $R_L$ shows that the frequency range for magnetic field sensor application can be modulated with appropriate load resistance $R_L$. This sample will allow for a low-magnetic ac field sensor in the low-frequency (near f=110 Hz).

Comparison Research on the Ease of Fitted Dress Shirt Patterns

  • Lee, Eunhae;Park, Sanghee
    • 패션비즈니스
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    • 제18권3호
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    • pp.91-103
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    • 2014
  • Shirts which have been a inner-wear in men's suit in the past, are being changed into an item that 20's men utilize to their individuality. Dress shirts have gotten out of its shape, becoming tight and slim with activity and fashion trend. In this study, two patterns of fitted dress shirts in a clothing construction text book were compared with the pattern of an apparel company with regard to the size tolerance and appearance silhouette; this comparison was performed through a fitting test and an appearance evaluation. According to the study, size tolerance of chest girth and waist girth were about 6~8cm and 10~18cm, respectively. Neck girth of the collar was tight in both the fitting test and appearance evaluation. Thus, the measurement value of the neck base girth had to be used for the collar pattern making. Moreover, approximately 35cm is a moderate size for the width on the upper arm in sleeve. Therefor the factors such as size tolerance of waist girth, height of sleeve cap, slim sleeve width and measurement value of neck base girth are being considered for the pattern making of fitted dress shirts.

Development of Plantar Pressure Measurement System and Personal Classification Study based on Plantar Pressure Image

  • Ho, Jong Gab;Kim, Dae Gyeom;Kim, Young;Jang, Seung-wan;Min, Se Dong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권11호
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    • pp.3875-3891
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    • 2021
  • In this study, a Velostat pressure sensor was manufactured to develop a plantar pressure measurement system and a C#-based application was developed to monitor and collect plantar pressure data in real time. In order to evaluate the characteristics of the proposed plantar pressure measurement system, the accuracy of plantar pressure index and personal classification was verified by comparing with MatScan, a commercial plantar pressure measurement system. As a result, the output characteristics according to the weight of the Velostat pressure sensor were evaluated and a trend line with the reliability of r2 = 0.98 was detected. The Root Mean Square Error(RMSE) of the weighted area was 11.315 cm2, the RMSE of the x coordinate of Center of Pressure(CoPx) was 1.036 cm and the RMSE of the y coordinate of Center of Pressure(CoPy) was 0.936 cm. Finally, inaccuracy of personal classification, the proposed system was 99.47% and MatScan was 96.86%. Based on the advantage of being simple to implement and capable of manufacturing at low cost, it is considered that it can be applied to various fields of measuring vital signs such as sitting posture and breathing in addition to the plantar pressure measurement system.

고전압 전기장을 이용한 하수처리장 방류수 중의 대장균군 소독에 관한 연구 (A Study on the Disinfection of Coliform Group in the Effluent of Sewage Plant by High Voltage Electric Field Treatment)

  • 이민규;정근식;감상규
    • 한국환경과학회지
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    • 제17권7호
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    • pp.817-826
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    • 2008
  • Using high voltage electric fields induced by high voltage AC (10-12 kV/cm, 20 kHz) and pulsed (20-30 kV/cm, 40 Hz) electric field generator as a semipermanent and environment-friendly disinfecting apparatus, the disinfection effect of coliform group in the effluent of sewage plant was investigated. The effects of electric field strength, treatment time, discharge area of a discharge tube, water quality factors (electric conductivity, pH and SS) on its death rate were examined. The death rate of coliform group was increased with increasing electric field strength and treatment time. For AC and pulsed electric field generator, the critical electric field strength was 6 kV/cm and 2 kV/cm, respectively, and the critical treatment time was 5 min and 2 min, respectively, regardless of electric field strength. Comparing the death rate of coliform group by AC and pulsed electric fields used in this study, its death rate was higher for the latter than the former, but did not increase linearly with increasing electric field strength. The results obtained for the effects of discharge area, electric conductivity, pH and SS on the death rate of coliform group using AC electric field (12 kV/cm, 20 kHz) were as follows: its death rate showed the trend to increase linearly with increasing discharge area; for the effect of electric conductivity, its death rate was increased with increasing electric conductivity, regardless of ionic species, increased with increasing cationic valency, but was similar between the same cationic valency; the pH $5{\sim}9$ used in this study did not affect its death rate; its death rate was decreased with increasing SS concentration.

동결속도에 따른 닭고기의 냉동 저장 중 이화학적 변화 (The Effect of Freezing Rates on the Physico-Chemical Changes of Chicken Meat during Frozen Storage at -2$0^{\circ}C$)

  • 김영호;양승용;이무하
    • 한국가금학회지
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    • 제14권2호
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    • pp.145-151
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    • 1987
  • 식육을 장기저장 할 때 발생되는 단백질의 변성과 해동시 육량감소를 줄이기 위한 방법의 하나로써 최적동결방법을 모색하고자 동결속도에 따른 저장중 닭고기의 물리화학적 변화를 조사한 결과 동결속도가 빠를수록 pH증가가 지연되어 장기보존의 가능성을 보였다. TBA가 및 유리지방산 생성율은 저장기간이 길어짐에 따라 증가하는 추세를 보이고 있으나 부위육의 종류에 따라 동결속도의 영향이 다르게 나타나고 있다. 그러나 단백질추출성을 비교할 때 염용성단백질과 수용성단백질의 추출성은 부위육의 종류에 관계없이 3cm/hr이상의 동결속도에서 저장기간 중 추출성이 가장 높게 나타났으며, 이러한 경향은 다리살 보다 가슴살의 추출성이 더욱 높게 유지되고 있다. 이상의 결과에서 송풍동결기를 이용하여 닭고기를 동결시킬 경우 3cm/hr이상의 동결속도로 동결시켜 냉동저장 할 때 좋은 품질의 냉동육을 얻을 수 있는 것으로 판단되었다.

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