• Title/Summary/Keyword: central cavity

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The Natural Ingredient Application Method of Cigarette Filter (천연소재 담배 필터 적용 방법)

  • Kim, Min-Kyu;Yeo, Woon-Hyung;Kim, Soo-Ho;Oh, Kyung-Hwan;Jin, Yong-Sook;Hwang, Eui-Il
    • Journal of the Korean Society of Tobacco Science
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    • v.35 no.1
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    • pp.13-19
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    • 2013
  • The natural ingredient has been utilized variety of the food and medicine. The aromatherapy well known prevent disease and healthy promotion using the essential oil derived extracted plants. In this work, natural ingredient include herb granulated for application of tobacco filter. That used by granulation using fluidized bed granulator(top-spray, bottom-spray and tangential-spray) and wet granule method. According to ingredient can used granulating method selectivity. So, we used fluid-bed granulator and wet granule method. Grapefruit extract coated sugar particle using the bottom-spray method and red ginseng granule granulated red ginseng powder using the tangential-spray method in a fluidized bed. Then, these granules applied the tobacco filter after due consideration add amount and operation efficiency. As a result, wet granule was loaded dual filter because that similarity carbon granule. And it was fitted in added 3mg/mm, per tip in the tobacco end part. Another type, fuidized bed granules was filled cavity filter because it has high hardness, sphere shape.

Description of Feeding Apparatus and Mechanism in Nemopilema nomurai Kishinouye (Scyphozoa: Rhizostomeae)

  • Lee, Hye-Eun;Yoon, Won-Duk;Lim, Dong-Hyun
    • Ocean Science Journal
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    • v.43 no.1
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    • pp.61-65
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    • 2008
  • Feeding apparatus, mechanism and passage of ingested prey were described for Nemopilema nomurai (Scyphozoa: Rhizostomeae). N. nomurai medusae without central mouths have developed complicated canal systems connecting the tip of the tentacle and oral arm to the gut cavity. The number of junctions in the canal system increases with the bell diameter. The prey is gathered by paralyzing nematocyst at the tentacles and by adhering cirri at the oral arms and scapulets. They are engulfed into the terminal pore located at the oral arms and scapulets, and entered into the gut cavity via the canal system. The estimated digestion time is 1 hour and 20 min. The diameter of terminal pore is always about 1 mm, implying that they could not eat prey larger than that pore size. On the other hand, ephyrae have central mouths and could swallow prey as large as adults could. Exploitation of the same size of food by adult and ephyra implies that N. nomurai can affect seriously the whole food web, massively ingesting micro- and mesozooplankton and cutting the energy transfer toward the higher level of carnivores.

Analysis of Fluid-Induced Vibration in the APR1400 Steam Generator Tube (신형경수로1400 증기발생기 전열관의 유체유발진동 해석)

  • 이광한;정대율;변성철
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.84-91
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    • 2003
  • Flow-Induced Vibration of steam generator tubes may result in fretting wear damage at the tube-to-support locations. KSNP(Korean Standard Nuclear Power plant) steam generators experienced fretting wear in the upper part of U-bend above the central cavity region of steam generators. This region has conditions susceptible to the flow-induced vibration, such as high flow velocity, high void fraction, and longer unsupported span. To improve its performance, APR1400 steam generator is designed with additional supports in this region to reduce unsupported span and to reduce peak velocity in the central cavity region. In this paper, we examined its performance improvement using ATHOS code. The thermal-hydraulic condition in the region of secondary side of APR1400 steam generator is obtained using the ATHOS3 code. The effective mass for modal analysis is calculated using the void fraction, enthalpy, and operating pressure information from ATHOS3 code result. With the effective mass distribution along the tube, natural frequency and mode shape is obtained using ANSYS code. Finally, stability ratios and real mean squared displacements for selected tubes of the APR1400 steam generator are computed. From these results, the current design of the APR1400 steam generator are examined.

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Secondary Hyperalgesia to Heat Stimuli Induced by Continuous Deep Pain: A Case Report

  • Park, Jun-Hyong;Kang, Jin-Kyu;Shim, Young-Joo
    • Journal of Oral Medicine and Pain
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    • v.41 no.4
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    • pp.195-199
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    • 2016
  • Central sensitization represents a functional change of second order neuron induced by continuous deep pain input and maintained by psychosocial factors. When afferent neurons are involved with central sensitization, secondary hyperalgesia can appear. Secondary hyperalgesia is an increased sensitivity to stimulation without a local cause. Reports on secondary hyperalgesia to heat stimuli are relatively rare compared to mechanical stimuli. And there were few reports of secondary hyperalgesia to heat stimuli in the oral cavity. We presented a case of secondary hyperalgesia to heat stimuli in the gingival area induced by continuous odontogenic pain with a review of the related literature.

Irradiation Effect on Silo Dry Storage Systems for CANDU Spent Nuclear Fuel

  • Taehyung Na;Yeji Kim;Donghee Lee;Taehyeon Kim;Sunghwan Chung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.22 no.2
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    • pp.117-128
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    • 2024
  • The 300 concrete silo systems installed and operated at the site of Wolsong nuclear power plant (NPP) have been storing CANDU spent nuclear fuel (SNF) under dry conditions since 1992. The dry storage system must be operated safely until SNF is delivered to an interim storage facility or final repository located outside the NPP in accordance with the SNF management policy of the country. The silo dry storage system consists of a concrete structure, liner steel plate in the inner cavity, and fuel basket. Because the components of the silo system are exposed to high energy radiation owing to the high radioactivity of SNF inside, the effects of irradiation during long-term storage must be analyzed. To this end, material specimens of each component were manufactured and subjected to irradiation and strength tests, and mechanical characteristics before and after irradiation were examined. Notably, the mechanical characteristics of the main components of the silo system were affected by irradiation during the storage of spent fuel. The test results will be used to evaluate the long-term behavior of silo systems in the future.

A COMPARATIVE STUDY ON THE APICAL LEAKAGE OF RETROFILLING AFTER APICAL CAVITY PREPARATION WITH ULTRASONIC INSTRUMENT (초음파 기구에 의한 치근단 와동형성후 역충전의 밀폐성에 대한 연구)

  • Lee, Hyeong-Il;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
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    • v.18 no.1
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    • pp.197-204
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    • 1993
  • This study was conducted to evaluate and compare the apical leakage in the following retrofilling techniques after apical resection; No apical cavity preparation and no retrofilling(control group), Amalgam(group I) or silver glass ionomer cement(group II) retrofilling after apical cavity preparation with mini contra-angle and bur, Amalgam(group III) or silver glass ionomer cement(group N) retrofilling after apical cavity preparation with ultrasonic micro endo tip. Extracted ninety upper anterior and lower canine teeth were fixed in skull simulators and root canals were prepared with step-back method and obturated with gutta-percha and zinc oxide eugenol sealer. Obturated roots were resected 2mm from apical ends and apical cavities of 1mm width and 2mm depth were prepared and retrofilled by above mentioned methods. After application of nail varnish on all surface except resected surface, apical 1/3 of the roots were placed in 1% methylene blue solution for 3 days. After longutudinal sectioning to expose central parts of filled materials, depths of penetrated dye were measured by measuring microscope and were analyzed statistically. The results were as follows. 1. Having no relation with instruments used in apical cavity preparation, amalgam retrofilling groups(group I and II) showed less apical leakage which was not significant statistically than no retrofilling group(control group) (P<0.05), but silver glass ionomer cement retrofilling gruoups(group II and IV) showed significantly less apical leakage than no retrofilling group(control group) (P<0.01). 2. In the groups retrofilled with the same material, the apical leakage in cavities prepared with ultrasonic micro endo tip (group III and IV) was less than that in cavities prepared with mini contra-angle and bur(group I and II), but not significant statistically(P>0.05). 3. When apical cavities were prepared with same instrument. the egroups retrofilled with silver glass ionomer cement(group II and IV) showed significantly less apical leakage than the groups retrofilled with amalgam(group I and III)(<0.01).

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Relationship between Formants and Constriction Areas of Vocal Tract in 9 Korean Standard Vowels (우리말 모음의 발음시 음형대와 조음위치의 관계에 대한 연구)

  • 서경식;김재영;김영기
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.5 no.1
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    • pp.44-58
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    • 1994
  • The formants of the 9 Korean standard vowels(which used by the average people of Seoul, central-area of the Korean peninsula) were measured by analysis with the linear predictive coding(LPC) and fast Fourier transform(FFT). The author already had reported the constriction area for the Korean standard vowels, and with the existing data, the distance from glottis to the constriction area in the vocal tract of each vowel was newly measured with videovelopharyngograms and lateral Rontgenograms of the vocal tract. We correlated the formant frequencies with the distance from glottis to the constriction area of the vocal tract. Also we tried to correlate the formant frequencies with the position of tongue in the vocal tract which is divided into 2 categories : The position of tongue in oral cavity by the distance from imaginary palatal line to the highest point of tongue and the position in pharyngeal cavity by the distance from back of tongue to posterior pharyngeal wall. This study was performed with 10 adults(male : 5, female : 5) who spoke primary 9 Korean standard vowels. We had already reported that the Korean vowel [i], [e], $[{\varepsilon}]$ were articulated at hard palate level, [$\dot{+}$], [u] were at soft palate level, [$\wedge$] was at upper pharynx level and the [$\wedge$], [$\partial$], [a] in a previous article. Also we had noted that the significance of pharyngeal cavity in vowel articulation. From this study we have concluded that ; 1) The F$_1$ is related with the oral cavity articulated vowel [i, e, $\varepsilon$, $\dot{+}$, u]. 2) Within the oral cavity articulated vowel [i, e, $\varepsilon$, $\dot{+}$, u] and the upper pharynx articulated vowel [o], the F$_2$ is elevated when the diatance from glottis to the constriction area is longer. But within the lower pharynx articulated vowel [$\partial$, $\wedge$, a], the F$_2$ is elevated when the distance from glottis to the constriction area is shorter. 3) With the stronger tendency of back-vowel, the higher the elevation of the F$_1$ and F$_2$ frequencies. 4) The F$_3$ and F$_4$ showed no correaltion with the constriction area nor the position of tongue in the vocal tract 5) The parameter F$_2$- F$_1$, which is the difference between F$_2$ frequency and F$_1$ frequency showed an excellent indicator of differenciating the oral cavity articulated vowels from pharyngeal cavity articulated vowels. If the F$_2$-F$_1$ is less than about 600Hz which indicates the vowel is articulated in the pharyngeal cavity, and more than about 600Hz, which indicates that the vowel is articulated in the oral cavity.

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The Mode of Detection of Helicobacter pylori in Saliva and Subgingival Plaques of Adult Periodontitis Patients (성인형 치주염 환자의 타액 및 치은연하치태에서 Helicobacter pylori의 발현양상)

  • An, Jong-Mo;Na, Myoung-Su;Kim, Byung-Ock
    • Journal of Periodontal and Implant Science
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    • v.34 no.4
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    • pp.723-731
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    • 2004
  • Helicobacter pylori(H. pylori) has been associated with the cause of chronic gastritis, peptic ulcers and gastric cancer. Although it may be transmitted through the oral cavity, it is unknown whether the oral cavity acts as a reservoir of H. pylori. The purpose of this study was to investigate the mode of detection of H. pylori in oral cavity of adult periodontitis patients with plaque and periodontal pocket which atmosphere is grown well H. pylori. We analysed detection rate of H. pylori in saliva and subgingival plaques of 17 adult periodontitis patients without symptoms of gastroduodenal disease by nested PCR. Samples tested comprised saliva and subgingival plaques from central incisor, 1st premolar and 1st molar. H. pylori DNA was not identified in saliva from all patients. The detection rate in subgingival plaque from incisors, premolars and molars was 5.9%, 5.9% and 17.7%, respectively. In conclusion, the dental plaque and periodontal pocket (especially, of molars) in adult periodontitis can be favorable reservoir of H. pylori and may be the source of infection and transmission of H. pylori.

CAVITATION FLOW SIMULATION FOR A 2-D HYDROFOIL USING A HOMOGENEOUS MIXTURE MODEL ON UNSTRUCTURED MESHES (비정렬 격자계에서 균질혼합 모델을 이용한 2차원 수중익형 주위의 캐비테이션 유동 해석)

  • Ahn, S.J.;Kwon, O.J.
    • Journal of computational fluids engineering
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    • v.17 no.1
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    • pp.94-100
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    • 2012
  • In this paper, the cavitating flows around a hydrofoil have been numerically investigated by using a 2-d multi-phase RANS flow solver based on pseudo-compressibility and a homogeneous mixture model on unstructured meshes. For this purpose, a vertex-centered finite-volume method was utilized in conjunction with 2nd-order Roe's FDS to discretize the inviscid fluxes. The viscous fluxes were computed based on central differencing. The Spalart-Allmaras one equation model was employed for the closure of turbulence. A dual-time stepping method and the Gauss-Seidel iteration were used for unsteady time integration. The phase change rate between the liquid and vapor phases was determined by Merkle's cavitation model based on the difference between local and vapor pressure. Steady state calculations were made for the modified NACA66 hydrofoil at several flow conditions. Good agreements were obtained between the present results and the experiment for the pressure coefficient on a hydrofoil surface. Additional calculation was made for cloud cavitation around the hydrofoil. The observation of the vapor structure, such as cavity size and shape, was made, and the flow characteristics around the cavity were analyzed. Good agreements were obtained between the present results and the experiment for the frequency and the Strouhal number of cavity oscillation.

A Case of Infected Huge Lymphangioma in Pelvic Cavity (골반강에 발생한 감염된 거대 림프관종 1예)

  • Choi, Woo-Seok;Lee, Seong-Ho;Chung, Seok-Young;Song, Phil-Hyun;Baek, Un-Gi;Cho, Chul-Kyu;Park, Tong-Choon;Choi, Joon-Hyuk
    • Journal of Yeungnam Medical Science
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    • v.19 no.1
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    • pp.63-67
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    • 2002
  • Lymphangioma is a benign tumor resulted from abnormal communication between large dermal lymphatic channels and central lymphatic system. The tumor is encountered more often in the neck and axilla and less often in mediastinum, omentum, retroperitoneum, and scrotum. It rarely developes at urogenital system, and there has been no previous description of lymphangioma involving the bladder wall in Korea. We report a case of 35-year-old female with infected huge lymphagioma ansing from pelvic cavity and involving bladder wall.

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