• Title/Summary/Keyword: ice-2

Search Result 1,286, Processing Time 0.025 seconds

Freezing Characteristics in a Horizontal Rectangular Channel with the Two-Dimensional Protuberances (2차원 직사각형 덕트 내부에 돌기부를 갖는 흐름의 동결특성에 관한 연구)

  • Oh, Cheol
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.27 no.6
    • /
    • pp.721-727
    • /
    • 2003
  • Freezing of turbulent water flow between two horizontal cooled parallel plates with the separated region has been investigated experimentally. The flow separation was induced by vertical plates (two-dimensional plates) situated at the inlet of the rectangular channel. The degree of flow separation was varied by employing vertical thin plates with various heights. Three kinds of the vertical plates with 8.0, 9.8 and 12.5 mm in height were utilized. The Reynolds number and cooling temperature ratio were ranged from $3.45\times10^3 to 1.73\times10^4$ and 7.0 to 20.0 respectively, The measurements show that the flow separation influenced remarkably on the local ice formation characteristics. The location of the first ice layer and the average heat transfer at the ice surface were found be correlated as a function of the Reynolds number, the cooling temperature ratio, and the orifice height ratio.

A study on engine performance of EGR valve problem in Hybrid vehicles (하이브리드 자동차의 EGR 밸브 오작동 시 엔진 성능에 미치는 영향)

  • Song, Rak Hyun;cho, Haeng Muk
    • Journal of Energy Engineering
    • /
    • v.24 no.3
    • /
    • pp.34-39
    • /
    • 2015
  • Recently, Air pollution is gradually increasing which are coming from the exhaust of the ICE vehicles in the world. ICE vehicle exhaust gas and $CO_2$ are widely suspected of contributing to the called greenhouse effect, fueling fears of global warming. Therefore, many countries are striving to decrease the vehicle exhaust gas and have developed a variety of policies as air pollution regulation plans. To comply with the regulations, automotive industry has developed hybrid vehicles, which have features of both ICE vehicles and electric vehicles. Hybrid car is eco-friendly and has lowered exhausting gases and improved fuel efficiency. This research has been written to show that break down cases with EGR valve in hybrid cars, steadily increasing in use, and to help with on-site maintenance.

Oxygen Isotope Data of Winter Water in the Western Weddell Sea: Preliminary Results

  • Khim, Boo-Keun;Park, Byong-Kwon;Kang, Sung-Ho
    • Journal of the korean society of oceanography
    • /
    • v.33 no.1-2
    • /
    • pp.1-7
    • /
    • 1998
  • In the western Weddell Sea, winter mixed layer is characterized by near-freezing temperature and higher salinity due to brine injection through sea-ice formation. This layer becomes Winter Water being capped by warmer and less saline Antarctic Surface Water during the sea-ice melt-ing season. In this study, Winter Water was preliminarily identified by the oxygen isotopic com-positions. The ${\delta}^{18}$O values of Winter Water show the progressively increasing trend from south to north in the study area. It presumably reflects the enhanced mixing with Antarctic Surface Water due to the extent of influence by low S'"0 value of sea-ice/glacier meltwater. Correlations between salinity and 6'"0 values of seawater can be used to more generally characterize Winter Water with a view to identification. However, the prediction on the degree of mixing from these relationships needs more detailed isotope data, although this study allows the oxygen isotopic composition of seawater as a tracer to identify the water mass.

  • PDF

Effect of IceWave® organic nanoscale patches on reduction of musculoskeletal pain

  • Piven, Emily;Dharia, Rupesh;Jones, Karen;Davis, Chuck;Nazeran, Homer
    • CELLMED
    • /
    • v.3 no.1
    • /
    • pp.5.1-5.5
    • /
    • 2013
  • In this pilot dual-site study with LifeWave IceWave$^{(R)}$ patches, using subjects as their own controls, data were acquired from a convenience sample of 16 males and 24 females, 50% Caucasian-Americans, 50% Hispanic-Americans, ages 20 - 85 with neuromuscular pain. The hypothesis was: the application of IceWave$^{(R)}$ patches to the skin will reduce one's perception of pain. Subjects were tested at baseline (without any patches), and then at 1 and 3 h on day 1 and at 1 h on days 2 - 5 after patch application. At every time point, the mean change, indicative of one's perception of pain, was highly significantly (p < 0.0001) reduced, with a statistical power of 100% compared to baseline. Based on these findings, the hypothesis was accepted as true.

Studies on the Optimum Method of Cold Transport of Marine Products I. Transport of Iced Mackerel (수산물 저온수송의 최적방법에 관한 연구 I. 고등어의 빙장수송)

  • Hur Jong-wha;Ham Nack-kie;Lee Jong-Gap;Choi Sun-Hong;Kim Jin-kook
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
    • /
    • v.9 no.2
    • /
    • pp.111-117
    • /
    • 1980
  • The optimum methods of transport of fresh mackerel caught at korean coast and neighboring sea were investigated. The quality of mackerel after 3 day-stored with ice showed that the freshness were still kept. The temperature fluctuation of mackerel during transport with ice from Busan to Seoul indicated below $5^{\circ}C$, recommended by I.I.R. Heat loss of iced mackerel in transit was calculated and converted into ice weight in case of cargo truck and insulated truck. It was assumed that the semi-dressed mackerels were more effective and economic than the round ones during transport.

  • PDF

Effects of Pressure-shift Freezing on the Structural and Physical Properties of Gelatin Hydrogel Matrices

  • Kim, Byeongsoo;Gil, Hyung Bae;Min, Sang-Gi;Lee, Si-Kyung;Choi, Mi-Jung
    • Food Science of Animal Resources
    • /
    • v.34 no.1
    • /
    • pp.33-39
    • /
    • 2014
  • This study investigates the effects of the gelatin concentration (10-40%, w/v), freezing temperatures (from $-20^{\circ}C$ to $-50^{\circ}C$) and freezing methods on the structural and physical properties of gelatin matrices. To freeze gelatin, the pressure-shift freezing (PSF) is being applied at 0.1 (under atmospheric control), 50 and 100 MPa, respectively. The freezing point of gelatin solutions decrease with increasing gelatin concentrations, from $-0.2^{\circ}C$ (10% gelatin) to $-6.7^{\circ}C$ (40% gelatin), while the extent of supercooling did not show any specific trends. The rheological properties of the gelatin indicate that both the storage (G') and loss (G") moduli were steady in the strain amplitude range of 0.1-10%. To characterize gelatin matrices formed by the various freezing methods, the ice crystal sizes which were being determined by the scanning electron microscopy (SEM) are affected by the gelatin concentrations. The ice crystal sizes are affected by gelatin concentrations and freezing temperature, while the size distributions of ice crystals depend on the freezing methods. Smaller ice crystals are being formed with PSF rather than under the atmospheric control where the freezing temperature is above $-40^{\circ}C$. Thus, the results of this study indicate that the PSF processing at a very low freezing temperature ($-50^{\circ}C$) offers a potential advantage over commercial atmospheric freezing points for the formation of small ice crystals.

Three dimensional Kinematic Analysis of Sweep Shot in Ice Hockey (아이스하키 스위프 샷(Sweep shot) 동작의 3차원 운동학적 분석)

  • Choi, Ji-Young;Moon, Gon-Sung
    • Korean Journal of Applied Biomechanics
    • /
    • v.16 no.4
    • /
    • pp.49-59
    • /
    • 2006
  • The purpose of this study was to investigate the relations between the segments of the body, the three dimensional anatomical angle according to sweep shot in ice hockey. The subjects of this study were five professional ice hockey players. The reflective makers were attached on anatomical boundary line of body. For the movement analysis three dimensional cinematographical method(APAS) was used and for the calculation of the kinematic variables a self developed program was used with the LabVIEW 6.1 graphical programming(Johnson, 1999) program. By using Eular's equations the three dimensional anatomical Cardan angles of the joint and ice hockey stick were defined. 1. In three dimensional linear velocity of blade the Y axis showed maximum linear velocity almost impact, the X axis(horizontal direction) and the Z axis(vertical direction) maximum linear velocity of blade did not show at impact but after impact this will resulted influence upon hitting puck. 2. The resultant linear velocity of each segment of right arm showed maximum resultant linear velocity at impact. It could be suggest that the right arm swing patterns is kind of push-like movement. therefore the upper arm is the most important role in the right arm swing. 3. The three dimensional anatomical angular displacement of trunk in flexion-extension showed flexion all around the wrist shot. The angular displacement of trunk in internal-external rotation showed internal rotation angle at the backswing top and and increased the angle after the impact. while there is no significant adduction-abduction. 4. The three dimensional anatomical angular displacement of trunk showed most important role in wrist shot. and is follwed by shoulder joints, in addition the movement of elbow/wrist joints showed least to the shot. this study result showed upperlimb of left is more important role than upperlimb of right.

The Experimental Study of Ice Thermal Storage for Falling Film Type - Sprint Coil Type - (스파이럴형 냉동코일을 사용한 유하액막식 빙축열조에서 열전달현상에 관한 실험적연구)

  • Lee, C.M.;Kim, D.H.;Cho, N.C.;Kim, I.G.;Park, S.R.;Choi, K.K.;Yim, C.S.
    • Solar Energy
    • /
    • v.19 no.2
    • /
    • pp.1-8
    • /
    • 1999
  • The heat transfer characteristics of ice storage system of falling film type using sprial coil is investigated. The experimental facilities consisted of a water tank, spiral coils located above the tank, an upper water distributor, and a circulating water pump. Water is distributed uniformally over the spiral coils and it forms falling thin films. In the process of freezing, ice is formed on outside of the spiral coils through recirculation of tank water. In the process of melting, ice is melted with return water from the heat load, while the water is chilled again and drops into the tank. The results of falling film type of ice thermal storage system are as follows. The highly efficient shower flowrates for icing is near $3{\ell}/min$. Icing rates on spiral coils is rosed while brine flowrates is increased. Lower brine temperature is not only increased freezing rates but. also become higher total icing weight and overall heat transfer coefficient. Smaller shower flowrates is obtained lower water temperature on outlet for a long time. The amounts of quantity can be detected more accurately by measuring storage tank weight.

  • PDF

Biochemical Adaptation to the Freezing Environment - the Biology of Fish Antifreeze Proteins

  • Li, Zhengjun;Li, n Qingsong;Low Woon-Kai;Miao Megan;Hew Choy L.
    • Ocean and Polar Research
    • /
    • v.25 no.4
    • /
    • pp.607-615
    • /
    • 2003
  • Many organisms are known to survive in icy environments. These include both over wintering terrestrial insects and plants as well the marine fish inhabiting high latitudes. The adaptation of these organisms is both a fascinating and important topic in biology. Marine teleosts in particular, can encounter ice-laden seawater that is approximately $1^{\circ}C$ colder than the colligative freezing point of their body fluids. These animals produce a unique group of proteins, the antifreeze proteins (AFPs) or antifreeze glycoproteins (AFGPs) that absorb the ice nuclei and prevent ice crystal growth. Presently, there are at least four different AFP types and one AFGP type that are isolated from a wide variety of fish. Despite their functional similarity, there is no apparent common protein homology or ice-binding motifs among these proteins, except that the surface-surface complementarity between the protein and ice are important for binding. The remarkable diversity of these proteins and their odd phylogenetic distribution would suggest that these proteins might have evolved recently in response to sea level glaciations just 1-2 million years ago in the northern hemisphere and 10-30 million years ago around Antarctica. Winter flounder, Pleuronectes americanus, has been used as a popular model to study the regulation of AFP gene expression. It has a built-in annual cycle of AFP expression controlled negatively by the growth hormone. The signal transduction pathways, transcription factors and promoter elements involved in this process have been studied in our laboratory and these studies will be presented.