• Title/Summary/Keyword: significant wave period

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A study of the economic effects of weather and climate information on marine logistics (해상운송업의 기상기후정보 경제적 효과에 관한 연구)

  • Lho, Sangwhan;Lim, Dongsoon
    • Environmental and Resource Economics Review
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    • v.23 no.1
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    • pp.1-19
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    • 2014
  • Weather seems to influence industries in a variety of ways. On a day-to-day basis, it is the most volatile external factor influencing consumer and market behavior. And, because weather is constantly changing, industries must deal with a continuously shifting array of opportunities and risks. This study aims to examine how climate and weather changes and information, as external environmental factors, have affected the Korean industries, particularly marine shipping and logistics. To find out the economic value of marine weather information, we use measurable results of VVOS(Vessel and Voyage Optimization Services) in the ocean shipping, which the marine weather software tool can save fuel costs up to 4%. When the fuel saving is same as VVOS's performance, the saving of Korean flag ship is estimated about 62 billion won and the saving of total flag ship is estimated about 519 billion won. However, coastal shipping companies have been struggling with the heavy weather factors, such as wave height, wave period and wind. Major findings are that wind and wave height have a significant negative effect on cargo transport, while wave period has a significant positive effect on cargo transport. And to conclude, when we use efficiently the marine weather information, we can increase cargo transport and save fuel costs etc.

A Study on the Auto-diagnosis Plethysmograph by Novel Algorithm for Radial Pulse Detection (새로운 맥파 인식 알고리즘을 적용한 자동 맥파 시스템에 관한 연구)

  • 박승환;홍승홍
    • Journal of Biomedical Engineering Research
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    • v.17 no.2
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    • pp.241-246
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    • 1996
  • This paper describes a new system that detects radial pulse wave and allows the diagnosis of malfunctions of cardiovascular system by analyzing the waveforms with the newly proposed algorithm. The system consists of a sensor part and a data processing part within which a new detection algorithm is incorporated In acquiring radial pulse signal noninvasively, the sensor used in this system is a new combinational fiber-optic sensor which has a detecting Part and a transmitting Part. Also, In order to analyze the characteristics of pulsation quantitatively, the algorithm proposed in this paper is a method that runs in parallel with both the data of ECG and differential pulse simultaneously. these concepts are based upon the idea that thfee Q points of ECG give obious discrimination of one entire period of pulse in any abnormal cases, and newly defined feature lines at the differential counterpart can be used to recogrlize sDme significant points in one period of pulses.

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Three-dimensional Simulation of Wave Reflection and Pressure Acting on Circular Perforated Caisson Breakwater by OLAFOAM (OLAFOAM에 기초한 원형유공케이슨 방파제의 반사율 및 작용파압에 관한 3차원시뮬레이션)

  • Lee, Kwang-Ho;Bae, Ju-Hyun;Kim, Sang-Gi;Kim, Do-Sam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.29 no.6
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    • pp.286-304
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    • 2017
  • In this study, we proposed a new-type of circular perforated caisson breakwater consisting of a bundle of latticed blocks that can be applied to a small port such as a fishing port, and numerically investigated the hydraulic characteristics of the breakwater. The numerical method used in this study is OLAFOAM which newly added wave generation module, porous media analysis module and reflected wave control module based on OpenFOAM that is open source CFD software published under the GPL license. To investigate the applicability of OLAFOAM, the variations of wave pressure acting on the three-dimensional slit caisson were compared to the previous experimental results under the regular wave conditions, and then the performance for irregular waves was examined from the reproducibility of the target irregular waves and frequency spectrum analysis. As a result, a series of numerical simulations for the new-type of circular perforated caisson breakwaters, which is similar to slit caisson breakwater, was carried out under the irregular wave actions. The hydraulic characteristics of the breakwater such as wave overtopping, reflection, and wave pressure distribution were carefully investigated respect to the significant wave height and period, the wave chamber width, and the interconnectivity between them. The numerical results revealed that the wave pressure acting on the new-type of circular perforated caisson breakwaters was considerably smaller than the result of the impermeable vertical wall computed by the Goda equation. Also, the reflection of the new-type caisson breakwater was similar to the variation range of the reflection coefficient of the existing slit caisson breakwater.

Prediction on Mooring Tension & Motion Response Characteristics of a Floating Dock in Regular Waves (규칙파 중 플로팅 도크의 운동응답특성 및 계류장력 추정)

  • Oh, Young-Cheol;Gim, Ok-Sok;Ko, Jae-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.19 no.2
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    • pp.200-206
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    • 2013
  • The paper was investigated on the mooring forces(or tension) and motion response characteristics for a 8-point mooring floating dock in regular waves using a commercial code(AQWA). To achieve the aim of the research, a numerical simulation was adapted on an inner port environment condition, which the water depth is 10 meters, significant wave amplitude(1.05 m). wave period(3.85 sec), wind speed(20.21 m/s), wind and current direction ($90^{\circ}$), incident waves(${\chi}=180^{\circ}$, $135^{\circ}$ and $90^{\circ}$). The dimension of the numerical model is length(140 m), breadth(32 m), depth(14.6 m). The maximum length of a mooring line is 120m. We can expected that roll and pitch motions appeared in beam seas better than head sea. the mooring forces also indicated higher in bean seas than in head seas including wind forces.

Feasibility Study of Submerged Floating Tunnels Moored by an Inclined Tendon System

  • Won, Deokhee;Kim, Seungjun
    • International journal of steel structures
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    • v.18 no.4
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    • pp.1191-1199
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    • 2018
  • Concepts of submerged floating tunnels (SFTs) for land connection have been continuously suggested and developed by several researchers and institutes. To maintain their predefined positions under various dynamic environmental loading conditions, the submerged floating tunnels should be effectively moored by reasonable mooring systems. With rational mooring systems, the design of SFTs should be confirmed to satisfy the structural safety, fatigue, and operability design criteria related to tunnel motion, internal forces, structural stresses, and the fatigue life of the main structural members. This paper presents a feasibility study of a submerged floating tunnel moored by an inclined tendon system. The basic structural concept was developed based on the concept of conventional cable-stayed bridges to minimize the seabed excavation, penetration, and anchoring work by applying tower-inclined tendon systems instead of conventional tendons with individual seabed anchors. To evaluate the structural performance of the new type of SFT, a hydrodynamic analysis was performed in the time domain using the commercial nonlinear finite element code ABAQUS-AQUA. For the main dynamic environmental loading condition, an irregular wave load was examined. A JONSWAP wave spectrum was used to generate a time-series wave-induced hydrodynamic load considering the specific significant wave height and peak period for predetermined wave conditions. By performing a time-domain hydrodynamic analysis on the submerged floating structure under irregular waves, the motional characteristics, structural stresses, and fatigue damage of the floating tunnel and mooring members were analyzed to evaluate the structural safety and fatigue performance. According to the analytical study, the suggested conceptual model for SFTs shows very good hydrodynamic structural performance. It can be concluded that the concept can be considered as a reasonable structural type of SFT.

Reproduction of Extreme Waves Caused by Typhoon MAEMI with Wave Hindcasting Method, WAM (II) - Characteristics of extreme waves generated by Typhoon MAEMI in the south coast of Korea - (제3세대 파랑추산모형을 이용한 태풍 '매미'의 극한파랑 재현 (II) - 태풍 '매미'가 야기한 우리나라 남해안 일대의 극한파랑 특성 -)

  • Shin Seung-Ho;Hong Keyyong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2004.11a
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    • pp.219-225
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    • 2004
  • Following a preceding study if Shin et al.(2004), wave fields for a month if September if 2003 are simulated based on the modified WAM cycle 4 model that enables the precise wave hindcasting with fine spatial meshes, and characteristics of extreme waves at the south roast if Koreo are analyzed The accuracy if applied wave model is verified by comparing computed wave parameters and corresponding ones measured at Ieodo ocean research station. The wave hindasting if typhoon 'Maemi' with an hour time interval reveals the extreme wave characteristics at 4 primary locations if south coast of Korea as follows: 1) At the front sea of Chaguido in the south of Jeju-do, the maximum significant wave height, moon wave period and mean wave direction appear to be 7.41m, 13.65s and $6.4^{\circ}$, respectively at 16:00 KST if Sep. 12, 2003. 2) At the entrance of Masan Bay, 12.50m, 13.65s and $1.2^{\circ}$ at 21:00 KST if Sep. 12. 3) At the front sea of Suyoung Bay, 13.85m, 13.81s and $0.2^{\circ}$ at 22;00 KST if Sep. 12. 4) At the front sea of Ulsan port, 11.00m, 13.25s and $28^{\circ}$ at 23:00 KST if Sep.

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Reproduction of Extreme Waves Caused by Typhoon MAEMI with Wave Hindcasting Method, WAM (II) - Characteristics of extreme waves generated by Typhoon MAEMI in the south coast of Korea - (제3세대 파랑추산모형을 이용한 태풍 ‘매미’의 극한파랑 재현 (II) - 태풍 ‘매미’가 야기한 우리나라 남해안 일대의 극한파랑 특성 -)

  • Shin, Seung-Ho;Hong, Key-Yong
    • Journal of Navigation and Port Research
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    • v.28 no.8
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    • pp.745-751
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    • 2004
  • Following a preceding study of Shin et al.(2004), wave fields for a month of September of 2003 are simulated based on the modified WAM cycle 4 model that enables the precise wave hindcasting with fine spatial meshes, and characteristics of extreme waves at the south coast of Korea are analyzed The accuracy of applied wave model is verified by comparing computed wave parameters and corresponding ones measured at Ieodo ocean research station. The wave hindcasting of typhoon 'Maemi' with an hour time interval reveals the extreme wave characteristics at 4 primary locations of south coast of Korea as follows: 1) At the front sea of Chaguido in the south of Jeju-do, the maximum significant wave height, mean wave period and mean wave direction appear to be 7.41m, 13.65s and $6.4^{\circ}$ respectively at 16:00 KST of Sep. 12, 2003. 2) At the entrance of Masan Bay, 12.50m, 13.65s and $1.2^{\circ}$ at 21:00 KST of Sep. 12. 3) At the front sea of Suyoung Bay, 13.85m, 13.81s and $0.2^{\circ}$ at 22;00 KST of Sep. 12. 4) At the front sea of Ulsan port, l1.00m, 13.25s and $2.8^{\circ}$ at 23:00 KST of Sep. 12.

Physiologic state and behavioral response to sponge bathing in premature infants (스폰지 목욕에 대한 미숙아의 생리적상태 및 행동반응)

  • Lee Hae Kyung;Hong Kyung Ja;Nam Eun Sook;Lee Young Hee;Jung Eun Ja
    • Child Health Nursing Research
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    • v.6 no.1
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    • pp.32-50
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    • 2000
  • A descriptive exploratory design was used in this study to evaluate the effects of sponge bathing on physiological(heart rate, heart period, vagal tone, oxygen saturation, respiration) and behavioral responses in newly born 40 preterm infants from intensive care unit of S University Hospital in Seoul. Data has been collected from October, 1997 to March, 1999. The infants were between 27-33 weeks gestational age at birth, and were free of congenital defects. The subjects entered the protocol when they were medically stable (determined by initiation of feeding and discontinuation of all respiratory support) but still receiving neonatal intensive care. The infants' physiologic parameters were recorded a 10 - minute before, during, and after bathing. Continuous heart rate data were recorded on a notebook computer from the infant's EKG monitor. The data were digitized off-line on software(developed by Lee and Chang in Wavelet program) which detected the peak of the R wave for each heart beat and quantified sequential R-R intervals in msec(i.e. heart periods). Heart period data were edited to remove movement artifact. Heart period data were quantified as : 1) mean heart period; 2) vagal tone. Vagal tone was quantitfied with a noninvasive measure developed by Porges(1985) in Mxedit software. To determine behavioral status, tools were developed by Scafidi et al(1990) were used. Collected data were analyzed with the SPSS program using paried t-test, ANOVA, and Pearson correlation. The result were as follow. 1. The results of the ANOVAs indicated that vagal tone were signifcantly lower during bathing than baseline and post-bathing. There were significant differences in heart period and heart rate levels across the bathing. But the mean oxygen saturations and respirations were no differences. Also, there were no significant differences on behavioral sign, motor activity, behavioral distress, weight changes, morbidity, and hospitalization period. 2. To evaluate the relation between vagal tone and subsequent parameters, the two groups (the high group had 19 subjects and low group had 21subjects) were divided by the mean baseline vagal tone. Vagal tone measured prior to bathing were significantly associated with respiration before bathing, vagal tone during bathing, and the magnitude of change in both vagal tone. But, other subsequent reactivities were no differences in two groups. 3. Correlations were also calculated between vagal tone and the subsequent physiological reactivities from baseline through after- bathing. Correlations were significant between baseline vagal tone and baseline heart rate, between baseline vagal tone and baseline heart period, between baseline vagal tone and oxygen saturation after bathing. In summary, the bathing in this study showed a stressful stimulus on premature infants through there was significance in the physiological parameters. In addition, our study represents the documentation that vagal tone reactivity in response to clearly defined external stimulation provides an index of infant's status.

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An Overview on Vibration or Wave Therapy in Korea (진동, 파동치료에 관한 국내 연구 동향)

  • Lee, Jae Heung;Beag, Ji You;Chang, Sung Jin;Pil, Gam Mai
    • Journal of Korean Medical Ki-Gong Academy
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    • v.20 no.1
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    • pp.15-67
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    • 2020
  • Objective : The purpose of this study is to identify the trends of vibration(or wave) therapy in Korea, to actively utilize vibration(or wave) therapy, and to help research activities of vibration therapy in Korean Medicine. Methods : The following Korean words "진동기", "진동요법", "진동운동", "진동치료", "파동요법", "파동운동", "파동치료" were searched on three specialized search sites (RISS, NAL, DBpia). Trends of vibration therapy were analyzed through the selected researches suitable for this study among these searched researches in an overview format. Results : 1. A total of 8,116 studies were searched and a total of 365 studies were finally selected 2. From 2000 to 2019, when research began to increase in earnest, there were 17.45±10.28 studies per year, and the AGR(Average Annual Growth Rate) was 11.92%. 3. In the main field of research, the 'Medicine and Pharmacy' was the largest with 147(40.16%) studies. In the Middle Field, the 'Kinesiology' was the largest with 99(27.05%) studies. In the study design, 'RCT(Randomized Controlled trial)' was the largest with 138(47.75%) studies. In the Age Group, 'Youth' was the largest with 126(48.84%) studies. 4. The average of the number of participants was 24.90±17.44. 5. The most used Intervention was the 'WBV(Whole Body Vibration)' with 177(61.25%) studies. 6. The average of Intervention Period was 5.99±4.14 weeks, while the maximum was 36 weeks. 7. The journal that published the most research papers is 'K. J. of Sports Science(체육과학연구;13)', and the society is 'Rehabilitation Engineering And Assistive Technology Society of Korea(한국재활복지공학회; 14)'. The University that published the most dissertations is 'Sahmyook University(11)'. 8. The authors who published the most studies are Ju-Hwan O(8) as the main author and Tae Kyu Kwon(18) as the co-author (including the thesis Director). In an integrated analysis of the authors and co-authors, Tae Kyu Kwon published the most numerous studies(19) Conclusions : 1. The study of vibration or wave therapy has been increasing noticeably every year. 2. The major academic Fields studying vibration or wave therapy are the 'Kinesiologic Field', 'Physical Therapy Field', and 'Biomedical Engineering Field'. 3. The most chosen method of study design on vibration or wave treatment was 'RCT', and there was no significant change in the annual presentation rate. 4. Types of vibration or wave therapy could be classified as 'LVS(Local Vibration Stimulation)', 'WBV(Whole Body Vibration)', 'MV(Micro Vibration)', 'BV(Bio Vibration)' and 'SWV(Sound Wave Vibration)', and the study on Whole Body Vibration is most active. 5. Most of the studies of vibration or wave therapy were on musculoskeletal systems, but there were very few studies on internal diseases.

Clinical, Hematological and Blood Chemical Changes in Korean Native Goats Following Administration of Combelen (한국재래산양(韓國在來山羊)에 있어서 Combelen 투여(投與)가 임상소견(臨床所見) 및 혈액성분(血液成分)에 미치는 영향(影響))

  • Jang, In Ho
    • Korean Journal of Veterinary Research
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    • v.18 no.1
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    • pp.1-7
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    • 1978
  • In order to detect the clinical effect of combelen which is used for sedation of domestic animals, 10 heads of clinically healthy Korean native goats were used in this study. They were divided into two groups; one is dose level of 1ml per 10 kg of body weight with 1% combelen and the other is dose level of 3 ml. Clinical observations and changes in blood components after administration of combelen were made. 1. There was no adverse effect due to combelen, but sedative effect was insufficient. 2. During sedative period the changes in heart rate and respiratory rate showed noticeable change, and body temperature was slightly decreased. 3. In ECG recordings, except for slight changes in T wave, significant change was not observed. 4. Erythrocytes, leukocytes, hemoglobin concentration and packed cell volume showed tendency to decrease during the period of sedation. 5. SGOT activity showed a remarkable increase and BUN showed a great decrease 24 hours after administration in the group of 3ml/10kg. Blood glucose level increased during the period of sedation in both groups.

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