• 제목/요약/키워드: water power

Search Result 5,435, Processing Time 0.032 seconds

An Ocean Wave Simulation Method Using TMA Model (TMA 모델을 이용한 해양파 시뮬레이션 방법)

  • Lee Nam-Kyung;Baek Nakhoon;Kim Ku Jin;Ryu Kwan Woo
    • The KIPS Transactions:PartA
    • /
    • v.12A no.4 s.94
    • /
    • pp.327-332
    • /
    • 2005
  • In the field of computer graphics, we have several research results to display the ocean waves on the screen, while we still not have a complete solution yet. Though ocean waves are constructed from a variety of sources, the dominant one is the surface gravity wave, which is generated by the gravity and the wind. In this Paper, we Present a real-time surface gravity wave simulation method, derived from a precise ocean wave model in the oceanography. There are research results based on the Pierson-Moskowitz(PM) model[1], which assumes infinite depth of water and thus shows some mismatches in the case of shallow seas. In this paper, we started from the Texel, Marsen and Arsloe(TMA) model[2], which is a more precise wave model and thus can be used to display more realistic ocean waves. We derived its implementation model for the graphics applications and our prototype implementation shows about 30 frames per second on the Intel Pentium 4 1.6GHz-based personal computer. Our major contributions to the computer graphics area ill be (1) providing more user-controllable parameters to finally generate various wave shapes and (2) the improvement on the expression power of waves even in the shallow seas.

A Study on Drying Kinetics of Low Rank Coal(Indonesia-IBC) through the Fixed-Bed Reactor Experiments (저등급석탄(低等級石炭)(인도네시아 IBC)의 고정층(固定層) 반응기(反應器) 실험(實驗)을 통한 건조(乾操) 반응속도론(反應速度論) 연구(硏究))

  • Kang, Tae-Jin;Jeon, Do-Man;Jeon, Young-Sin;Kang, Suk-Hwan;Lee, Si-Hyun;Kim, Sang-Do;Kim, Hyung-Taek
    • Resources Recycling
    • /
    • v.19 no.6
    • /
    • pp.43-50
    • /
    • 2010
  • The crisis of energy gives rise to the growing concerns over continuing uncertainty in the energy market. Under these circumstances, there are also increasing interests on coals. In particular, Low Rank Coal (LRC) is receiving gradual attentions from green industry. But due to is high moisture content range from 30 - 60%, drying process has to be preceded before being utilized as power plant. In this study drying kinetics of LRC is induced by using a fixed-bed reactor. The drying kinetics was evaluated in from of the particle size, the inlet gas temperature, the drying time, the gas velocity, and the LID ratio. The consideration of the reynold's number was taken for correction of gas velocity, particle size and LID was taken for correction of reactor diameter, packing height of coal. As being seen as characteristic of drying coal, it can be found that fixed-bed reactor can contributed to active drying of free water. In this sense, it could be considered that phase boundary reaction is appropriate mechanism.

Field observation of sediment suspension in the surf zone (쇄파대의 저질부유에 관한 현지관측)

  • Shin, Seung-Ho;Kuriyama, Yoshiaki
    • Journal of Navigation and Port Research
    • /
    • v.27 no.4
    • /
    • pp.455-463
    • /
    • 2003
  • Time series of suspended sediment concentration, surface elevation and velocity were measured and analysed to investigate the role of waves and the predominance of infra-gravity wave component for sediment suspension phenomena in the surf zone. For the investigation in detail, we adopted the cross spectral analysis method between suspended sediment concentration and the characteristic values of wave, and ensemble average analysis method about long-period wave component, which is dominant to sediment suspension in the measurement point. The obtained results are summarized as follows: 1)The relationship between suspended sediment concentration and the characteristic values of wave is stronger for the long-period standing wave components(about 60s and 30s where the nodal point of the first mode and the anti-nodal point of the second mode are located at the measurement point, respectively) than the long wave components(about 100s), which have the most energetic power, 2) and also, it is cleared that suspended sediment concentration is increased in the case of the phase, the velocity components of the first mode long-period standing wave(60sec) were accelerated toward on-shore direction, that is, the water surface in offshore side is higher than on-shore side.

An Exploration on Prescription of Resistance Training for Geriatric Physical Therapy (노인물리치료를 위한 저항트레이닝 처방에 대한 탐색)

  • Shin Hong-Cheul;Jeong Dong-Hyuk
    • The Journal of Korean Physical Therapy
    • /
    • v.15 no.1
    • /
    • pp.61-81
    • /
    • 2003
  • There can be little dissension that the ultimate goal of all physical therapy interventions with the elderly is to restore or maintain the highest level of function possible for the individual. Whenever physical therapists take on this challenge, they assist elders in maintaining their identities as competent adults. Advancing age is associated with profound changes in body composition, including increased fat mass, decreased fat-free mass(particularly muscle), decreased total body water and decreased bone density. Along with these changes in body compositions, and perhaps as a direct result of them, elderly people have lower energy needs, reduced strength and functional capacity and a greatly increased risk for such diseases as noninsulin-dependent diabetes mellitus and osteoporosis. Resistance training is considered a promising intervention for reversing the loss of muscle function and the deterioration of muscle structure that is associated with advanced age. This reversal is thought to result in improvements in functional abilities and health status in the elderly by increasing muscle mass, strength and power and by increasing bone mineral density. In the past couple of decades, many studies have examined the effects of Resistance training on risk factors for age-related diseases or disabilities. We have explored the positive and negative aspects of older adults' participation in resistance training programs. The benefits to older adults are reported to be increased strength, endurance, muscle capacity, and flexibility; more energy; and improved self-image and confidence. The negative aspects include some pain or stiffness and other nonspecific problems. The positive and negative aspects of resistance training are therefore very similar to those in younger populations. Scientific investigations over the past 10 years have demonstrated that resistance training can be safely and successfully implemented in older populations. Even the frail and very sick elderly can benefit and improve their quality of life. Proper design and progression of a resistance training program for older adults is vital to optimal benefits from resistance exercise. The results of data provided by this research on resistance training for health shows that there is enough existing evidence to conclude that resistance training, particularly when incorporated into a comprehensive fitness program, can offer substantial health benefits which can be obtained by persons of all ages. These benefits, including improvements in functional capacity, translate into an improved quality of life.

  • PDF

Quality Characteristics and Antioxidant Activities of Cookies Added with Pleurotus eryngii Powder (새송이버섯 분말을 첨가한 쿠키의 품질 및 항산화활성)

  • Kim, Ye-Ji;Jung, In-Kyung;Kwak, Eun-Jung
    • Korean Journal of Food Science and Technology
    • /
    • v.42 no.2
    • /
    • pp.183-189
    • /
    • 2010
  • This study examined the quality characteristics and antioxidant activities of cookies added Pleurotus eryngii powder. There were no significant differences in bulk density or water content between the doughs. Spread factors and leavening rates of cookies decreased with increasing Pleurotus eryngii powder content. However, the loss rates of cookies showed no significant differences. L values decreased with increasing Pleurotus eryngii powder content while a values were gradually increased. b values showed no significant differences among the samples. Hardness, total phenol compound content, ferric reducing antioxidant power (FRAP) and DPPH radical scavenging activity of cookies were significantly increased with increasing Pleurotus eryngii powder content. In a descriptive test, the color, flavor, palatability, hardness and graininess were all increased with increasing Pleurotus eryngii powder content. In a preference test, color and flavor were the highest in the 10% group without significant differences. Texture was preferred in the control-20% groups without significant differences. However, taste and overall acceptability were the highest in the 10% group.

Effect of Trehalose on Rheological Properties of Bread Flour Dough (Trehalose가 빵용 반죽의 Rheology 특성에 미치는 영향)

  • Kim, Young-Ja;Lee, Jeong-Hoon;Chung, Koo-Chun;Lee, Si-Kyung
    • Korean Journal of Food Science and Technology
    • /
    • v.46 no.3
    • /
    • pp.341-346
    • /
    • 2014
  • This study was conducted to evaluate the effect of trehalose on the rheological properties of bread flour dough. Farinographic and viscographic properties, pH, total titratable acidity (TTA), and fermentation power were analyzed for flour dough rheology. Flour dough containing trehalose showed greater water absorption capacity and longer development time. However the stability, degree of softening, and farinograph quality number (FQN) were lower for the trehalose-containing flour dough, however, these factors decreased with increasing amounts of trehalose. Trehalose did not affect the beginning of gelatinization temperature and maximum viscosity temperature of flour. The maximum viscosity was the lowest with 6% trehalose, the end of final holding period, breakdown and setback values decreased with increasing amounts of trehalose. Flour dough with 4% trehalose had the lowest pH value for 120 min fermentation at $30^{\circ}C$, and the highest TTA value. Addition of 4% and 6% trehalose showed larger fermentation volume of dough than the control. The results suggested that trehalose positively affected the rheological properties of flour dough such as bread volume, softness, and staling delay.

Changes in physicochemical characteristics of sorghum among different varieties and at different harvest stages after heading (품종 및 수확시기를 달리한 수수의 이화학 특성 변화)

  • Kim, Sung Kook;Jung, Gun Ho;Lee, Jae Eun;Lee, Byoung Kyu;Woo, Koan Sik
    • Korean Journal of Food Science and Technology
    • /
    • v.50 no.3
    • /
    • pp.260-266
    • /
    • 2018
  • The change in physicochemical characteristics of sorghum among different varieties and at different harvest stages after heading were evaluated. The proximate compositions and chromaticity of sorghum were significantly different, depending on their varieties and harvesting times. Water solubility was high in sorghum harvested on the $50^{th}$ day after heading; however, the swelling power was reversed. Total polyphenol content of Hwanggeumchal, Nampungchal, and Sodamchal was 17.60-24.62, 17.88-24.67, and 17.37-22.37 mg GAE/g, respectively, and the flavonoid content was 10.43-13.50, 9.68-13.85, and 9.52-12.46 mg CE/g, respectively. The DPPH radical-scavenging activities were 9.94-16.21, 11.42-16.54, and 10.12-15.16 mg TE/g, respectively, and the ABTS radical-scavenging activities were 8.85-19.99, 10.51-20.24, and 9.71-17.93 mg TE/g, respectively. Total polyphenol and flavonoid contents, and radical scavenging activities were high in sorghum harvested on the $40-50^{th}$ day after heading. As a result, it is considered that sorghum varieties such as Hwanggeumchal, Nampungchal, and Sodamchal should be harvested on the $40^{th}$ day after heading.

Antioxidant activities and quality characteristics of noodles containing Allium senescens L. (두메부추 첨가 국수의 항산화 활성 및 품질특성)

  • Yang, Eun-Young;Han, Young-Sil
    • Korean Journal of Food Science and Technology
    • /
    • v.52 no.2
    • /
    • pp.156-161
    • /
    • 2020
  • This study was designed to evaluate the quality characteristics and antioxidant activities of noodles containing Allium senescens L. powder (0, 2, 4, 6, and 8%). With an increase in the consumption of Allium senescens L., there was a decrease in pH (p<0.001), water absorption ratio, volume expansion ratio, and turbidity (p<0.05). The colorvalue showed that the addition of Allium senescens L. decreased the L and b values. On the other hand, a value was increased (p<0.001). The mechanical texture of the noodles containing Allium senescens L. was decreased by the addition of Allium senescens L. considering its hardness and chewiness; however, it increased the adhesiveness, springiness, and cohesiveness (p<0.001). In the sensory evaluation, the noodles with 4% Allium senescens L. powder showed the best results (p<0.001). The total polyphenol content, total flavonoid content, DPPH radical scavenging, and reducing power were increased upon addition of Allium senescens L. powder (p<0.001).

Antioxidant and Alcohol Dehydrogenase Activity of Water Extracts From Abalone Containing Medicinal Plants (전복과 천연 식물류 복합물의 항산화 및 알코올대사 효소 활성)

  • Shin, Jung-Hye;Lee, Soo-Jung;Choi, Duk-Ju;Kang, Min-Jung;Sung, Nak-Ju
    • Korean journal of food and cookery science
    • /
    • v.24 no.2
    • /
    • pp.182-187
    • /
    • 2008
  • This study was performed to evaluate the possible production of a functional beverage derived from abalone and with several plants (AP). Five types of AP composites were prepared having different medicinal plant compositions (AP- I : abalone, garlic, jujube, Chinese matrimony fruit, dried orange peel, licorice root, zinger, honey; AP- II: abalone, garlic, black bean, Chinese matrimony fruit, cornus fruit, licorice root, zinger, honey; AP-III : abalone, jujube, arrow root, milk vetch, dried orange peel, licorice root, zinger, honey; AP-N: abalone, black bean, arrow root, milk vetch, cornus fruit, liquorice root, zinger, honey; AP-V : abalone, garlic, Chinese matrimony fruit, milk vetch, licorice root, zinger, honey). In vitro analysis were performed to examine the antioxidant contents and alcohol dehydrogenase activities of the composites. AP- II had the highest total phenol contents ($28.55{\pm}1.56\;mg/l00\;g$), and AP- V the highest level of flavonoids ($47.61{\pm}1.58\;mg/l00\;g$). At $78.89{\pm}0.16%$, AP- V displayed the strongest electron donating ability followed by AP-II($57.99{\pm}0.21%$) and API ($37.66{\pm}0.20%$). Reducing power was also significantly higher in AP- V. The Hydroxyl radical scavenging and SOD-like activities of all composites were less than 15% and 20%, respectively. At 12.5% alcohol concentration, ADH activity ranged from $114.47{\pm}2.18{\sim}121.39{\pm}4.36%$ and ALDH activity ranged from $100.04{\pm}2.90{\sim}129.54{\pm}4.80%$; AP- I , AP- II, and AP- Vin 12.5% of alcoholic concentration. The composites of AP- I , AP- II, and AP- V, all containing garlic and Chinese matrimony fruit, were significantly stronger than AP-III and AP-N. Finally, also at 12.5% alcoholic concentration, the ALDH activity of AP- V was higher than its ADH activity.

Physicochemical and Organoleptic Properties of Starch Isolated from Gamma-Irradiated Acorn (감마선 조사 도토리로부터 분리한 전분의 이화학적 및 관능적 특성)

  • Kwon, Joong-Ho;Kim, Soo-Jin;Lee, Jung-Eun;Lee, Soo-Jeong;Kim, Sung-Kon;Kim, Jeong-Sook;Byun, Myung-Woo
    • Korean Journal of Food Science and Technology
    • /
    • v.34 no.6
    • /
    • pp.1007-1012
    • /
    • 2002
  • Physicochemical and organoleptic properties were investigated in starch extracted from acorn gamma-irradiated for insect control. Hunter's color L, a, and b values were unchanged upon irradiation at 0.25 to 10 kGy. Scanning electron microscopic observation revealed no changes with gamma irradiation at 1 kGy, that is effective for disinifestation, whereas 10 kGy resulted in some clefts on the starch surface. X-ray diffraction analysis showed patterns of both amorphous and crystalline regions were not different among the treatment groups. Water-binding property, swelling power, solubility, and gelatinization patterns of starch were influenced by irradiation dose, but 1 kGy dose was not detrimental to the physicochemical properties. Textural parameters of acorn gel were relatively stable, but significant reductions were found in hardness, adhesiveness, and chewiness in samples irradiated at 3 kGy or higher. Rrsults revealed that irradiation at 1 kGy or lower could be applied for insect control without causing apparent changes in physicochemical and organoleptic properties of acorn starch.