• Title/Summary/Keyword: sea wave

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Spinal Motor Neuron and Electroencephalogram Changes after Different Kinesio Taping Method Therapy in normal People (키네시오 테이핑 적용 방식이 정상인의 척수운동신경원 흥분성과 뇌파 변화에 미치는 영향)

  • Bae, Sea-Hyun;Kim, Gi-Do;Kim, Kyung-Yoon
    • The Journal of the Korea Contents Association
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    • v.13 no.11
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    • pp.791-799
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    • 2013
  • This study to evaluate the spinal motor neuron and electroencephalogram effects of applying different kinesio taping method therapy in normal people. The study was performed on 16 healthy adults. We divide two group; group I(n=8); Tape along muscle, group II(n=8); Tape across muscle. Two different method taping were applied to gastrocnemius in two weeks. Spinal motor neuron measurement to evoke H-reflex, the posterior tibial nerve was stimulated. Electroencephalogram measurement for ${\beta}$-SMR, attached to active electrode C3, Cz, C4. The H-reflex, ${\beta}$-SMR results were measured before, immediately, one week later and two week later after the apply taping. The results of this study, spinal motor neuron change of group I were decreased ${\alpha}$-motor neuron and the duration time longer than group II(p<.05). Electroencephalogram change of group I were increased ${\beta}$-SMR and the duration time longer than group II(p<.05). Thus, we knew the taping along muscle was ${\beta}$-SMR brain wave more active and reduces the activity of spinal motor neuron.

Engineering Performance and Applicability of Eco-Friendly Concrete for Artificial Reefs Using Electric Arc Furnace Slags (전기로 슬래그를 활용한 인공리프용 친환경콘크리트의 공학적 성능 및 적용성)

  • Jo, Young-Jin;Choi, Se-Hyu
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.3
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    • pp.533-544
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    • 2015
  • Unlike the concrete structure built on land, that exposed to the marine environment is greatly degraded in durability due to the exposure to not only the physical action caused by sea wind, tide, and wave, but also the harsh conditions, including the chemical erosion and freeze-thaw which result from $SO_4{^{2-}}$, $Cl^-$ and $Mg^{2+}$ ions in seawater. In the process of the large scaled construction of submerged concrete structures, of course environmental hazardous substance, such as alkaline (pH) and heavy metals, may be leached. Thus, this issue needs to be adequately reviewed and studied. Therefore, this study attempted to develop a CSA (Calcium Sulfo Aluminate) activator using electric arc furnace reducing slags, as well as the eco-friendly concrete for artificial reefs using electric arc furnace oxidizing slag as aggregate for concrete. The strength properties of the eco-friendly concrete exposed to the marine environment were lower than those of the normal concrete by curing 28 days. This suggest that additional studies are needed to improve the early strength of the eco-friendly concrete. With respect to seawater resistance of the eco-friendly concrete, the average strength loss against 1 year of curing days reached 8-9%. the eco-friendly concrete using high volume of ground granulated blast furnace slags and high specific gravity of electronic arc furnace oxidizing slag demonstrated the sufficient usability as a freeze-thaw resistant material. With respect to heavy metal leaching properties of the eco-friendly concrete, heavy metal substances were immobilized by chemical bonding in the curing process through the hydration of concrete. Thus, heavy metal substances were neither identified at or below environmental hazard criteria nor detected, suggesting that the eco-friendly concrete is safe in terms of leaching of hazardous substances.

Transmittance Characteristics of Fishing Lamp in the Anchovy Scoop Fishery (멸치초망어업용 집어등 광력의 수중 투과특성)

  • 박성욱;배봉성;안희춘;서두옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.2
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    • pp.117-123
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    • 2001
  • Anchovy scoop nets, a kind of lift net have been used in the coastal area of Cheju and South sea of Korea. An incandescent lamp(AC 100V, 1kW) is being used as a fishing lamp for gathering anchovy. Fishing lamp was installed at 1m ahead of the prow and 1.5m higher than the water surface. The fishing lamp let fish school rise to the water surface and attract to bag net. Accordingly, a successful anchovy catching depends on controling of fishing lamp. On the study, the distribution of spectral irradiance illumination of incandescent lamp(1kw) and the irradiance efficiency of reflection plate were analyzed and discussed to investigate the ability of fishing lamp which can attract anchovy school effectively. The results obtained are summarized as follows : 1. Around 180% of irradiance efficiency of incandescent lamp was increased by using the reflection plate. The light of lamp was radiated into water with circular shape. 2. The irradiance illumination of incandescent lamp in air was a maximum in wave length of 994nm but it was 690nm at 0.5m and 1.0m of water depth. 3. The relationship between water depth(x) and water illumination(y) of vertical light is represented as follows : y=146.03e supper(-0.37x) 4. The light of incandescent lamp(1kW) pass through much better into vertical direction than horizontal but it was estimated that the light was not able to reach depth of 20m.

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Enhancement of Ionospheric Correction Method Based on Multiple Aperture Interferometry (멀티간섭기법에 기반한 이온왜곡 보정기법의 보완)

  • Lee, Won-Jin;Jung, Hyung-Sup;Chae, Sung-Ho;Baek, Wonkyung
    • Korean Journal of Remote Sensing
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    • v.31 no.2
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    • pp.101-110
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    • 2015
  • Synthetic Aperture Radar Interferometry (InSAR) is affected by various noise source such as atmospheric artifact, orbital error, processing noise etc.. Especially, one of the dominant noise source for long-wave SAR system, such as ALOS PALSAR (L-band SAR satellite) is the ionosphere effect because phase delays on radar pulse through the ionosphere are proportional to the radar wavelength. To avoid misinterpret of phase signal in the interferogram, it is necessary to detect and correct ionospheric errors. Recently, a MAI (Multipler Aperture SAR Interferometry) based ionospheric correction method has been proposed and considered one of the effective method to reduce phase errors by ionospheric effect. In this paper, we introduce the MAI-based method for ionospheric correction. Moreover we propose an efficient method that apply the method over non-coherent area using directional filter. Finally, we apply the proposed method to the ALOS PALSAR pairs, which include the west sea coast region in Korea. A polynomial fitting method, which is frequently adopted in InSAR processing, has been applied for the mitigation of phase distortion by the orbital error. However, the interferogram still has low frequency of Sin pattern along the azimuth direction. In contrast, after we applied the proposed method for ionospheric correction, the low frequency pattern is mitigated and the profile results has stable phase variation values within ${\pm}1rad$. Our results show that this method provides a promising way to correct orbital and ionospheric artifact and would be important technique to improve the accuracy and the availability for L-band or P-band systems.

Transmittance Characteristics by candlepower of Incandescent Lamp (백열등의 광력에 따른 수중 투과특성)

  • 박성욱;배봉성;안희춘;이정우;서두옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.38 no.4
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    • pp.293-299
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    • 2002
  • The anchovy scoop net fishery is one of the important in the South sea and coastal of Jeju of Korea. They are using incandescent lamp as a fishing lamp at night to gather anchovy shoals in the water surface. Fishing lamp (AC 100 V 500 W$\times$2~3 or AC 100 V 1 ㎾$\times$1) was installed at 1 m ahead of the prow and 1.5 m height from the water surface. The fishing lamp let anchovy shoals rise to the water surface and are attracted to bag net. On this study, the distribution of submarine illumination of 1㎾ and 2 ㎾ incandescent lamp were analyzed and discussed to investigate the ability of fishing lamp which can gather anchovy shoals effectively. The submarine illumination of incandescent lamp showed peak in wave length 690 nm. The relationship between submarine illumination (L) and water depth (Z) of 1 ㎾ and 2 ㎾ incandescent lamp in vertical light is 1 ㎾ : L = 3851. 9 $e^{-1.4587Z}$ $R^2$=0.9952 2 ㎾ : L= 8211.9 $e^{-1.2852Z}$ $R^2$=0.9977 The submarine illumination of 2 ㎾ incandescent lamp of 0~4 m layers appeared to be 3 to 4 times higher than 1 ㎾ incandescent lamp, and in more deep layers than 6 m appeared to be equal value of each lamp. The light of incandescent lamp (1 ㎾) pass through much better into vertical direction than horizontal, and submarine illumination of 20 m layers was 1.0 l$\chi$. Therefore, fishing lamp power is thought that 1 ㎾ incandescent lamp is more efficient than 2 ㎾ to gather anchovy shoals in depth of 15~20 m to water surface.

Effects on the Jeju Island of Tsunamis Caused by Triple Interlocked Tokai, Tonankai, Nankai Earthquakes in Pacific Coast of Japan (일본 태평양 연안의 Tokai, Tonankai 및 Nankai의 3연동지진에 의한 지진해일이 제주도 연안에 미치는 영향)

  • Lee, Kwang-Ho;Kim, Min-Ji;Kawasaki, Koji;Cho, Sung;Kim, Do-Sam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.4
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    • pp.295-304
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    • 2012
  • This study proposed a two-dimensional horizontal numerical model based on the nonlinear shallow water wave equations to simulate tsunami propagation and coastal inundation. We numerically investigated the possible impacts of tsunami caused by the triple interlocked Tokai, Tonankai and Nankai Earthquakes on the Jeju coastal areas, using the proposed model. The simultaneous Tokai, Tonankai and Nankai Earthquakes were created a virtual tsunami model of an M9.0 earthquake. In numerical analysis, a grid nesting method for the local grid refinement in shallow coastal regions was employed to sufficiently reproduce the shoaling effects. The numerical model was carefully validated through comparisons with the data collected during the tsunami events by 2011 East Japan Earthquake and 1983 central East Sea Earthquake (Nihonkai Chubu Earthquake). Tsunami propagation triggered by the combined Tokai, Tonanakai and Nankai, Earthquakes was simulated for 10 hours to sufficiently consider the effects of tsunami in the coastal areas of Jeju Island. The numerical results revealed that water level fluctuation in tsunami propagation is greatly influenced by water-depth change, refraction, diffraction and reflection. In addition, the maximum tsunami height numerically estimated in the coastal areas of Jeju Island was about 1.6 m at Sagye port.

A Study on the Performance of an 100 kW Class Tidal Current Turbine (100 kW급 조류발전용 터빈의 성능에 관한 연구)

  • Kim, Bu-Gi;Yang, Chang-Jo;Choi, Min-Seon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.2
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    • pp.145-152
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    • 2012
  • As the problems of global warming are brought up recently, many skillful solutions for developing new renewable energy are suggested. One of the most remarkable things is ocean energy. Korea has abundant ocean energy resources owing to geographical characteristics surrounded by sea on three sides, thus the technology of commercialization about tidal current power, wave power is demanded. Especially, Tidal energy conversion system is a means of maintaining environment naturally. Tidal current generation is a form to produce electricity by installing rotors, generators to convert a horizontal flow generated by tidal current into rotating movement. According to rotor direction, a tidal current turbine is largely distinguished between horizontal and vertical axis shape. Power capacity depends on the section size crossing a rotor and tidal current speed. We therefore investigated three dimensional flow analysis and performance evaluation using commercial ANSYS-CFX code for an 100 kW class horizontal axis turbine for low water level. Then We also studied three dimensional flow characteristics of a rotating rotor and blade surface streamlines around a rotor. As a result, We found that torque increased with TSR, the maximum torque occurred at TSR 3.77 and torque decreased even though TSR increased. Moreover we could get power coefficient 0.38 at designed flow velocity.

A Study on Environmentally Friend Counter Facilities for Improvement of Harbor Water Quality (항내수질 개선을 위한 친환경 외곽시설에 관한 연구)

  • Kim, Kang-Min;Kang, Suk-Hyong;Ryu, Ha-Sang;Kim, Sang-Hoon
    • Journal of Navigation and Port Research
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    • v.27 no.2
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    • pp.233-238
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    • 2003
  • Due to the impermeability of outer wall facilities such as Breakwaters which dissipates the wave energy and keeps harbor tranquility, the enclosed area of harbor becomes partially blocked and the water exchange can be reduced. Recent trends of port development protect water quality and emphasize Water-Front, so the method which enhances the circulation of harbor waters and the dilution of the water pollutants are studied. The best improvement of water quality is a remove of pollutant source on land, but an enclosed port must be enhanced the tidal exchange. For this end, the best improvement may be made a drain-route on the existing outer wall facilities. In this study, the numerical computations were carried out to predict the circulation of harbor waters and the tidal exchange through the drain-rout in the polluted harbor(Samchonpo-guhang) located at the east coast of South Sea. Computational models adopting FDM(Finite Difference Method) were used here and were already verified from the previous studies und ocean survey. As a result of this study, circulation and the tidal exchange at the harbor before and after introduction of drain-route were assessed.

Characteristics for Progressive Collapse Behavior and Ultimate Strength of Very Large Marine Structure (초대형 해상구조물의 붕괴거동 및 최종강도 특성)

  • Park, Joo-Shin;Ko, Jae-Yong;Lee, Kyoung-Woo
    • Journal of Navigation and Port Research
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    • v.33 no.5
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    • pp.315-321
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    • 2009
  • The Very Large Marine Structure has been widely used new method of ocean space instead of method for reclamation Therefore, VLFS is proposed to coincide on such request. It can be established regardless of nature of soil and height of water, and stream of flow exists under the floating structure, there is seldom effect in natural environment. Fuertherrnore, it can do easily to do assembly and taking to pieces due to expansion or removal. Based on the regulation by class, VLFS have to possess more than enough structural strength against severe wave loading induced by green sea condition Therefore, There are performed structural simulation as well as experimental test about expected loading scenario in order to examine the safety of structure. Up to now, various examinations based on the strength limit value of the main structural material have been done based on the elasticity response analysis. However, there is little finding about the collapse behavior and the safety when the load that exceeds the collapse of the material acts. In the present study, we investigated the collapse behavior based on the ultimate limit state calculated by FE-analysis.

Relationship between Some Weather Conditions and Immigration of the Brown Planthopper, Nilaparvata lugens Stal (벼멸구의 비래와 기상과의 관계)

  • 엄기백;박중수;이영인;최궤문;이문호;이정운
    • Korean journal of applied entomology
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    • v.27 no.4
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    • pp.200-210
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    • 1988
  • ABSTRACT Brown planthopper collection data by 151 light traps located throughout the southern part of Korean peninsula for 7 years from 1981 thru 1987 were analysed with each immigration wave in relation to daily weather charts when the immigration occurred, and summarized as below. 1) Most of the main immigration took place during the mid and late July, though there were some variations from year to year. 2) Number of the BPH collected at one time, and the number of the area where those immigrants where collected were increased when it occurred closer to the end of July. 3) Weather conditions when the immigration took place were divided into 4 types; (a) depression with stationary front passed over the central peninsula (A type, 12 times); (b) depression with stationary front passed over the southern sea (B type, 5 times); (c) stationary front passed over the central peninsula(C type, 7 times); (d) without depression and stationary front (D type, 2 times). 4) Whatever the types of the weather, those immigrations started to land from south-west part of the peninsula, and those numbers of immigrants were also grater at those south-western areas. 5) When common weather factors were counted from each weather chart of the days when thcse immigrations took place, presence of wind from south-west was 26 times, presence of stationary front was 24 times, and presence of depression was 17 times out of all 26 cases of immigration. 6) Therefore, it could be concluded that the immigration of the BPH into Korea is simply accompanied by the north$.$easterly flowing air currents, connected from south-east part of China through Korean peninsula. And other factors seem to be related with inducing their landing.anding.

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