• Title/Summary/Keyword: Plunging

Search Result 160, Processing Time 0.031 seconds

Breaking Wave Generation in the Laboratory (실험실에서의 쇄파발생)

  • Cho, Won-Chul;Michael Bruno
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.4 no.3
    • /
    • pp.178-186
    • /
    • 1992
  • An experimental study of deep-water breaking waves are performed by superposition of different wave frequencies, faster waves overtaking slow waves at a certain location. Large spilling and plunging breaking waves are generated near the expected breaking location. Wave steepness in spilling and plunging breakers significantly increases as the breaking point is approached and then decreases after breaking. Larger growth rate of the wave steepness in vigorous plunging breaking is observed. The fundamental wave frequencies in a wave group are dominant through the wave evolution, even in an intense plunging breaking event.

  • PDF

Analytic Study on the Axial Forces of a Double Offset Constant Velocity Joints in Consideration of Friction Effect (마찰을 고려한 이중 오프셋 등속조인트의 축력 해석에 관한 연구)

  • Bae, Byoung-Chul
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.16 no.2
    • /
    • pp.120-127
    • /
    • 2008
  • The constant velocity joint(CVJ) used for transmitting torque to the front wheels is an important part in automotive drive system. There are several types of constant velocity joints. Typically, they are classified by fixed and plunging constant velocity joints. The axial force generated in plunging constant velocity joints influences significantly the noise, vibration and harshness. For heaps of time, many constant velocity joint markers have been studying and developing a valid method to reduce the axial force and extensive tests have been carried out on rigs. This paper presents the analysis method to predict the axial force of a double offset constant velocity joint(DOJ), a kind of plunging constant velocity joint, and the influence of ball-cage dimension tolerance on the axial force.

Computation of Unsteady Flows over an Oscillating airfoil (진동하는 익형을 지나는 비정상 유동에 관한 계산)

  • Yang C. M.;Baek J. H.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 1999.05a
    • /
    • pp.125-130
    • /
    • 1999
  • A flowfields around a NACA0012 airfoil pitching about a 1/4 chord and plunging in vertical displacement are analyzed by solving two-dimensional compressible Navier-Stokes equations. A steady solution was solved first as a validation of the code used and the results were compared with experimental data. Then as a unsteady case, the oscillatory airfoil was solved to compare the results with experimental data. Oscillating rate of pitching and plunging motion was set to have analogy and the magnitude of plunging was set using the magnitude of pitching angle of attack. Finally combined pitching and plunging motion was solved to show the effect of 2 different types of oscillating motion of the airfoil.

  • PDF

The Sclerotherapy of Plunging with the Use of OK-432 (OK-432를 이용한 몰입성 하마종의 경화치료)

  • Kim, Sun-Gon;Lee, Jun-Ho;Kim, Myung-Gu;Rho, Myung-Ho
    • Korean Journal of Bronchoesophagology
    • /
    • v.13 no.1
    • /
    • pp.33-38
    • /
    • 2007
  • Background and Objectives: A plunging ranula represents a mucus escape reaction occuring because of the disruption of the sublingual salivary gland. It is commonly a condition of young adults, although the reported age range is 6-43 years. There is said to be a slightly female preponderance of about 1.9:1(F:M). Surgical incision has been considered the definite treatment, but sometimes complete excision is very difficult. Non-surgical treatment of these lesions has been attempted, but the results have not been satisfactory. In this study, we present our experiences with picibanil (OK-432) sclerotherapy for a plunging ranula. Materials and Methods: We retrospectively reviewed 41 patients who have undergone sclerotherapy with picibanil for plunging ranula. Information was collected on age, sex, a number of injection, post-sclerotherapy side effect and outcome of treatment. Results: 17 patients (41.5%) showed a complete response, and 20 patients (48.7%) showed inter-mediate response. No response was seen in 4 patients (9.8%). As a side effect of intracystic OK-432 injection therapy, fever (26.8%) and pain(39.0%) were observed. However, fever and pain disappeared after several days in all cases. Conclusion: The results are showing that OK-432 injection is an effective and safe treatment for plunging ranula.

  • PDF

Study on Plunging Wave Breaking near Ship Bow (선수 주위의 플런징 쇄파 연구)

  • Koo, Bon-Guk
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.22 no.3
    • /
    • pp.122-127
    • /
    • 2021
  • Flow features near the ship bow such as wave breaking, small scale phenomena have been studied using numerical methods. In this study, the bow shaped wedge was adopted which is from previous paper [1, 2] and the conditions of simulation were Re = 1.64 × 105) and Fr = 2.93. Star CCM+, one of the commercial CFD programs has been used for the simulations. Simulation results such as wave profiles near the ship bow, shape of plunging jet, air entrainment, and wave breaking process have been compared with previous experimental and numerical studies. Overall results showed good agreements with previous studies. Profiles of bow waves showed that overturning jet has been created and broken along the wedge. Plunging wave breaking has been observed along the wedge and four components of plunging wave breaking process were shown. It is confirmed that velocity near the overturing jet significantly increased during plunging wave breaking.

Effects of Cooling Rates and Plunging Temperatures on Survival of Hamster Embryos (동결속도와 침지온도가 Hamster 수정란의 생존성에 미치는 영향)

  • 윤도중;이규승;박창식;서길웅
    • Korean Journal of Animal Reproduction
    • /
    • v.11 no.3
    • /
    • pp.161-169
    • /
    • 1987
  • This experiment was carried out to investigate the optimal cooling rate and the plunging temperature into liquid nitrogen of the 8-cell hamster embryos. The female hamsters were induced to superovulate by intraperitoneal injection of 30 i.u. PMSG. Embryos were flushed from oviduct and uterine horn. Embryos were frozen and incubated with a modified Dulbecco's phosphate buffered saline, and equilibrated with 1.5M-dimethyl sulfoxide by a 3-step procedure. The cooling rate of samples was 1$^{\circ}C$/min from room temperature to -5$^{\circ}C$ and the samples were seeded at -5$^{\circ}C$. The plunging temperatures into liquid nitrogen were -20, -25, -30, -35, -40, -45, -50 and -55$^{\circ}C$ at 0.3$^{\circ}C$/min, 0.5$^{\circ}C$/min and 1$^{\circ}C$/min cooling rates, respectively. This mean numbers of ovulation points and recovered embryos were 59.4 and 48.4 appearing 81.6% recovery rate. The percentage of 8-cell embryos in recovered embryos was 68.2. The survival rates of embryos plunged at -45$^{\circ}C$ were 73.5% at 0.3$^{\circ}C$/min, 44.8% at 0.5$^{\circ}C$/min and 30.3% at 1$^{\circ}C$/min cooling rates, respectively. This mean numbers of ovulation points and recovered embryos were 59.4 and 48.4 appearing 81.6% recovery rate. The percentage of 8-cell embryos in recovered embryos was 68.2. The survival rates of embryos plunged at -45$^{\circ}C$ were 73.5% at 0.3$^{\circ}C$/min, 44.8% at 0.5$^{\circ}C$/min and 30.3% at 1$^{\circ}C$/min cooling rates, respectively. The survival rates at 0.3$^{\circ}C$/min were significantly high. Under the condition of 0.3$^{\circ}C$/min cooling rate, the survival rates of embryos according to the plunging temperature were 70.0% and 73.5% at -40 and -45$^{\circ}C$, and those were higher than other plunging temperatures. Under the condition of 0.5$^{\circ}C$/min and 1$^{\circ}C$/min cooling rates, the survival rates according to the plunging temperatures were lower than the cooling rate of 0.3$^{\circ}C$/min, showing the similar tendency at all the plunging temperatures. In conclusion, 8-cell hamster embryos showed the best survival rates at 0.3$^{\circ}C$/min cooling rate and -45$^{\circ}C$ plunging temperature.

  • PDF

Surgical Treatment of a Plunging Ranula using the Intraoral and Submandibular Approach (구강 내 접근과 하악하 절개를 통한 몰입성 하마종의 수술적 치료)

  • Kim, Jung Hong;Eun, Seok Chan;Baek, Rong Min
    • Archives of Craniofacial Surgery
    • /
    • v.11 no.2
    • /
    • pp.111-115
    • /
    • 2010
  • Purpose: A plunging ranula is relatively uncommon and represents a mucus escape reaction occurring from a disruption of the sublingual salivary gland. It is a common condition found in young adults, even though the reported age range is 2 - 61 years. We report our experience of a complete excision of a plunging ranula via the intraoral and submandibular approach. Methods: A 23-year-old man had a large protruding mass in the right submandibular area. Initially, the protruding mass appeared bilaterally but the left side disappeared spontaneously. The MRI findings revealed a homogenous fluid attenuation mass in the submandibular space, suggesting a ranula. The sublingual gland was extirpated through the intraoral approach and the ranula excised totally via the submandibular approach. Results: The patient had an uneventful postoperative course without infection, paralysis and tongue sensory changes, etc. The pathology findings were characteristic of a pseudocyst without a lining epithelium or endothelium but with a vascular fibro-conective tissue wall filled with mucinous fluid. No recurrence was observed on the submandibular area during the 8 month follow-up period. Conclusion: The combined intraoral approach and submandibular approach is an effective and highly recommended method for sublingual gland extirpation and complete excision of a plunging ranula.

Bilateral Plunging Ranula Arising from Accessory Submandibular Gland (부악하선에서 유발된 양측성 몰입성 하마종)

  • Choi, Hwan-Jun;Kim, Sun-Joo;Lee, Young-Man
    • Archives of Plastic Surgery
    • /
    • v.37 no.1
    • /
    • pp.75-78
    • /
    • 2010
  • Purpose: Whereas oral ranula is relatively common and presents as a cyst in the mouth, the plunging ranula is rare and manifests itself as a mass in the neck with or without an associated oral lesion. The purpose of this study is to examine the clinical characteristics of rare bilateral plunging ranula arising from accessory submandibular gland in order to provide our experience for its correct diagnosis and treatment. Methods: A 13-year-old girl manifests as a slow growing painless, non-mobile swelling in the anterior neck. She underwent surgery via a cervical approach. A pseudocyst was extirpated and adjacent accessory gland tissue and related lymph node were removed. Results: The histologic appearance is characteristically of a cyst, devoiding of epithelium or endothelium, with a vascular fibro-connective tissue wall containing some chronic inflammatory cells and macrophage stuffed with mucin. Pathologic findings represented a form of myxomatous degeneration and lined by condensed connective tissue and granulation tissue. The nature of the accessory gland tissue was same as subligual gland. Although total submandibular or sublingual gland excision was not performed, no recurrence was observed during 6 months follow-up periods. Conclusion: Usually, unilateral plunging ranula develops commonly because of rupture of sublingual gland duct by trauma and extravasation of salivary secretion to the adjacent tissue. But our case developed because of bilateral congenital accessory submandibular gland. This is thought to be a result from a congenital failure of canalization of the terminal end of the duct. Finally, the correct diagnosis is essential for the most effective treatment, which is excision of the ranula and related accessory salivary gland. We performed excision of accessory submandibular gland and plunging ranula and had a good result without recurrence.

Correlation Analysis of Social Sentiment and Stock Prices (사회적 감성과 주가의 상관성 분석)

  • Yun, Hongwon
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.19 no.7
    • /
    • pp.1593-1598
    • /
    • 2015
  • In this paper, we analyze the correlation between social sentiment and stock prices. Polarity analysis is conducted for the stock prices plunging and soaring duration. And it is performed for its prior period. Using these results, we analyze the relationship between the social sentiment and stock prices. We collected the past data of Dow Jones Industrial Average and detected the period of plunging and soaring. On the basis of the detected time, the New York Times articles are collected and polarity analysis is conducted. Frequency of negative terms is decreased and it of positive terms is increased during the stock prices soaring. There is a little difference between the frequency of negative and positive terms in the previous stock prices plunging or soaring. According to the correlation analysis, it shows a positive correlation between social sentiment and stock prices in the period of plunging and soaring. A significant correlation is not appeared in the previous stock prices plunging or soaring.

Case report of the management of the ranula

  • Choi, Moon-Gi
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.45 no.6
    • /
    • pp.357-363
    • /
    • 2019
  • Ranula is a mucocele caused by extravasation of the sublingual gland on the floor of the mouth. The most common presentation is a cystic mass in the floor of the mouth. A portion of the sublingual gland could herniate through the mylohyoid muscle, and its extravasated mucin can spread along this hiatus into submandibular and submental spaces and cause cervical swelling. This phenomenon is called plunging ranula. A variety of treatments for ranula has been suggested and include aspiration of cystic fluid, sclerotherapy, marsupialization, incision and drainage, ranula excision only, and excision of the sublingual gland with or without ranula. Those various treatments have shown diverse results. Most surgeons agree that removal of the sublingual gland is necessary in oral and plunging ranula. Four patients with ranula were investigated retrospectively, and treatment methods based on literature review were attempted.