• 제목/요약/키워드: Cone-plate

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Improved Measurements of the Rheological Property of Cement Paste using Plate/Plate and Truncated cone/Plate Sensors (Plate/Plate, Truncated Cone/Plate 센서를 이용한 시멘트반죽 유변학적 특성에 대한 개선된 측정)

  • 민병현
    • The Korean Journal of Rheology
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    • v.7 no.1
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    • pp.10-18
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    • 1995
  • Plate/plate 및 Truncated cone/plate 감지부를 이용한 시멘트반죽의 유변학적 특성 을 측정함에 있어 관련된 오차에 대한 실험 및 이론적 분석이 보고된다. 주요인자로는 감지 부 직경과 상하 감지부 사이의 간격이 고려되었다. Cone/plate 감지부의 원추끝을 깍아 간 격의 크기를 늘린 Truncated cone/plate 감지부의 토르크 분포에 대한 이론적 분석결과 원 추 간격이 0.7mm 까지 절단되더라도 8.5%의 오차범위내에서는 cone/plate 감지부의 역할을 수행하는 것으로 판단된다. 실험결과는 샘플주변의 상대습도가 결과에 영향을 끼치고 감지 부의 기하학적 요인에도 매우 민감함을 보여준다. 이결과는 정지시간을 포함한 오랜실험기 간동안 미소변형하에서 유변학적 특성을 연구하는데 도움이 될것으로 판단된다.

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Isolated tympanic plate fracture detected by cone-beam computed tomography: report of four cases with review of literature

  • Kalaskar, Ashita Ritesh;Kalaskar, Ritesh
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.43 no.5
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    • pp.356-360
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    • 2017
  • The tympanic plate is a small part of the temporal bone that separates the mandibular condyle from the external auditory canal. Fracture of this small plate is rare and usually associated with other bony fractures, mainly temporal and mandibular bone. There is a limited amount of literature on this subject, which increases the chance of cases being overlooked by physicians and radiologists. This is further supported by purely isolated cases of tympanic plate fracture without evidence of other bony fractures. Cone-beam computed tomography is an investigative three-dimensional imaging modality that can be used to detect fine structures and fractures in maxillofacial trauma. This article presents four cases of isolated tympanic plate fracture diagnosed by cone-beam computed tomography with no evidence of fracture involving other bones and review of the literature.

Impingement heat transfer within 1 row of circular water jets: Part 2-Effects of nozzle to heated surface distance (1열 원형 충돌수분류군에 의한 열전달의 실험적 연구 (제2보, 노즐-전열면간 거리의 영향))

  • 엄기찬;이종수;김상필
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.1
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    • pp.59-66
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    • 2000
  • In a previous paper, we have examined the effects of nozzle configuration and jet to jet spacing on the heat transfer of 1 row of circular water jets. In this paper, experiments have been conducted to obtain the effects of nozzle to target plate distances on the heat transfer of 1 row of 3 jets and 1 row of 5 jets. The nozzle configurations are Cone type, Reverse cone type and Vertical circular type. Nozzle to target plate distance H was varied from 16 mm(H/D=2) to 80mm(H/D=10). For fixed value of mass flow rate and nozzle to target plate distance, larger values of average Nusselt number were obtained for the smaller jet to jet spacing. For the array of water jets, the average heat transfer was decreased slightly with increasing nozzle to target plate distance at low jet velocity of $\textrm{V}_{o}$=3 m/s. However, except for $\textrm{V}_{o}$=8 m/s of 1 row of 5 jets, it was increased with increasing nozzle to target plate distance at high jet velocity of $\textrm{V}_{o}$$\geq$6m/s. We proposed to apply the nozzle configuration of maximum average heat transfer to each nozzle to target plate distance for 1 row of 3 jets, and, it was Reverse cone type nozzle for 1 row of 5 jets(Reynolds number$\geq$36000).

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Frequency Characteristics of the Return Loss of a Broadband Double-Cone Antenna with Shorting Plate (단락판을 갖는 이중 원추형 광대역 안테나의 반사손실 특성)

  • Jang, Seung-Hoon;Hong, Deok-Gi;Kim, Hyo-gyun;Jung, Sung-Woo;Kim, Ki-Chai
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.2
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    • pp.101-107
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    • 2016
  • This paper presents the characteristics of a double-cone broadband antenna with compact and three-dimensional structure that can be used in UWB system. The theoretical analysis is conducted using a finite difference time domain(FDTD) method. The parameters are the radius, a height of broadband double-cone antennas with shorting plate, and the number of plates on a ground plane. This paper examines influence of structural parameters on return loss. The results show that a condition for an optimum structure of broadband double-cone antennas with shorting plate exists. It also shows that the broadband double-cone antennas with shorting plate have radiation patterns similar to those of a dipole antenna. To verify the theoretical analysis, computed results are compared to experimental results.

The Correlation Analysis between Dynamic Cone Penetration Test and Plate Loading Test Results for Evaluation of Dam Conditions (제체 상태 평가를 위한 동적 콘 관입시험과 평판재하시험 결과의 상관관계 분석)

  • Jung, Young-Hoon;Kim, Seongmin;Lim, Jeong-yeul
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.4
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    • pp.33-38
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    • 2018
  • The internal erosion due to poor compaction of the material was the main cause of collapse of the embankment in Korea. The assessment of the compaction state of the dam body was a very important check in the safety diagnosis of the embankment. In this study, the correlation between dynamic cone penetration test and plate loading test which is the most typical compaction evaluation technique was analyzed to verify the applicability of the dynamic cone penetration test in evaluating the compaction state of the dam body. The standard penetration tests were carried out six times to define soil properties and depth of the test site. The spatial distributions were obtained by the Kriging method after 15 times of plate loading tests and 47 times of dynamic cone penetration tests. The Pearson correlation coefficient between the spatial distribution of the plate loading test and the dynamic cone penetration test spatial distribution at the constant penetration depth was calculated. The load distribution in the plate loading test and the blow counts at penetration depths of 5 cm, 10 cm and 15 cm in the dynamic cone penetration test showed a weak positive correlation.

A Study on the Mobility of Power Tiller in Wetland Rice Field (수도포장(水稻圃場)에서의 동력경운기(動力耕耘機) 주행성(走行性)에 관(関) 연구(硏究))

  • Lee, Kyou Seung;Lee, Yong Kook;Lee, Choong Yong;Park, Seung Je;Kim, Sang Hun
    • Journal of Biosystems Engineering
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    • v.9 no.2
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    • pp.8-18
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    • 1984
  • To investigate the most important factors affecting the mobility of power tiller and to find the method which can be used for predicting the mobility of power tiller in soft paddy field, a series of field experiment was performed with two models of power tiller (8ps and 6ps diesel). From the results obtained throughout field experiment, the following conclusions were derived. 1. The wheel sinkage of power tiller during both traveling and field operations, which mainly influence the mobility, could be predicted from both plate ($50{\times}100mm$) sinkage and soil cone index (30-degree cone with 2 and $6cm^2$ base area). 2. Prediction of wheel sinkage from the rectangular plate sinkage was found to be more suitable compared with the cone index. 3. The upper limit of rectangular plate sinkage was found as 15 centimeter for operation of power tiller in muddy field which is equivalent of $1kg/cm^2$ of $2cm^2$ cone index value.

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Investigation of the Three-Dimensional Turbulent Flow Fields of the Gas Swirl Burner with a Cone Type Baffle Plate(II)

  • Kim, Jang-kweon
    • Journal of Mechanical Science and Technology
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    • v.15 no.7
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    • pp.906-920
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    • 2001
  • This paper presents three-dimensional mean velocities, turbulent intensities and Reynolds shear stresses measured in the Y-Z plane of the gas swirl burner with a cone type baffle plate by using an X-type hot-wire probe. This experiments is carried out at the flow rate of 450ℓ/min which is equivalent to the combustion air flow rate necessary to heat release 15,000 kcal/hr in a gas furnace. Mean velocities and turbulent intensities etc. show that their maximum values exist around the narrow slits situated radially on the edge of and in front of a burner. According to downstream regions, they have a peculiar shape like a starfish because the flows going out of the narrow slits and the swirl vanes of an inclined baffle plate diffuse and develop into inward and outward of a burner. The rotational flow due to the inclined flow velocity going out of swirl vanes of a cone type baffle plate seems to decrease the magnitudes of mean velocities V and W respectively by about 30% smaller than those of mean velocity U. The turbulent intensities have large values of 50%∼210% within the range of 0.5

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Heat Transfer from Single and Arrays of Impinging Water Jets(I)-Single Water Jet- (단일수분류 및 수분류군에 의한 열전달(I)-단일수분류-)

  • Eom, Gi-Chan;Lee, Jong-Su;Yu, Ji-O
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.9
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    • pp.1105-1114
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    • 1997
  • The heat transfer characteristics of free surface water jet impinging normally against a flat uniform heat flux surface were investigated. This deals with the effect of three nozzle configurations (Cone type, Reverse cone type, Vertical circular type) on the local and the average heat transfer. Heat transfer measurements were made for water jet issuing from a nozzle of which exit diameter 8 mm. The experimental conditions investigated are Reynolds number range of 27000 ~ 70000( $V_{O}$=3 ~ 8 m/s), nozzle-to-target plate distances H/D=2 ~ 10, and radial distance from the stagnation point r/D ~ = 0 ~ 7.42. For all jet velocities of H/D=2, the local Nusselt number decreased monotonically with increasing radial distance. However, for H/D from 4 to 10, and for the jet velocity $V_{O}$.geq.7 m/s for Cone type nozzle and $V_{O}$.geq.6 m/s for the other type nozzles, the Nusselt number distributions exhibited secondary peaks at r/D=3 ~ 3.5. For Reverse cone type nozzle and Vertical circular nozzle, the maximum stagnation point heat transfer and the maximum average heat transfer occurs at H/D=8. But for the Cone type nozzle, the maximum stagnation and average heat transfer occurs at H/D=10, 4, respectively. From the optimum nozzle-to-target plate distance, the stagnation and the average heat transfer reveal the following ranking: Reverse cone type nozzle, Vertical circular type nozzle, Cone type nozzle.ozzle.

A Quality Survey of Packaged Ice Creams in Seoul Area (시판(市販) 아이스크림의 품질(品質)에 대(對)한 조사연구(調査硏究))

  • Hah, Duk-Mo;Shin, Hyo-Sun
    • Korean Journal of Food Science and Technology
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    • v.8 no.2
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    • pp.113-118
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    • 1976
  • For this study, from July to December in 1975, the total of 160 samples of packaged ice creams(75 samples of carton, 50 samples of cone, and 35 samples of bar), manufactued by five different plants, were collected at markets in Seoul city area. And the chemical composition and microbial quality of those were analyzed and compared with each other samples. The results obtained are as follows: 1. The average milk fat contents of ice cream samples were 6.28% in carton, 6.42% in cone and 4.94% in bar. 2. The average total solid contents of ice cream samples were 33.45% in carton, 34.22% in cone and 29.46% in bar. 3. The average total protein contents of ice cream samples were 3.45% in carton, 3.16% in cone and 2.42% in bar. 4. The average milk solids-not-fat contents of ice cream samples were 10.46% in carton, 8.52% in cone and 7.72% in bar. 5. The average milk lactose contents of ice cream samples were 6.42% in carton, 5.57% in cone and 4.94% in bar. 6. The average crude ash contents of ice cream samples were 0.86% in carton, 0.78% in cone and 0.67% in bar. 7. The average Reichert-Meissl values of ice cream samples were 28.82 in carton, 27.85 in cone and 25.97 in bar. 8. In the both experiments of standard plate count and coliform count, the samples of ice cream in cone and carton showed lesser numbers than those in the form of bars. Of a total 160 samples examined, 6 samples gave standard plate counts of over 40,000/ml and 14 samples gave coliform counts of over 10/ml.

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A Study on the Impact Fracture of Fragile Materials (취성재료의 충격파괴에 관한 연구 II)

  • 양인영;김택현;정낙규;이상호;김선규
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.6
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    • pp.1417-1425
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    • 1990
  • In this paper, when the glass plate of fragile material is subjected to impact load, the fracture pattern and the generation phenomenon of cone crack were theoretically clarified by using the analysis method of impulsive stress in the first paper. The numerical analysis results of strain distribution at a distance of 0.1cm, from the impact loading point to 5cm, were compared with experimental results. The main conclusions obtained are as follows; (1) The generation phenomenon of cone crack at the impact fracture of the glass plate can be analytically confirmed by using the three dimensional dynamic theory of elasticity. And the numerical analysis results of strain distribution using this theory are relatively in close agreement with the crack size obtained from the impact fracture experiment. (2) After the stress wave generated at the impact point propagated to the spherical compressive wave, this stress wave reflected from the back surface and reached again at the surface of the plate to the spherical stress wave. Then the generation of cone crack can be confirmed along the stress wave surface. (3) The plate is the thicker, the more is the generation phenomenon of cone crack at the lower impact velocity range (20m/s-35m/s). Because the fracture generate before the maximum tensile stress acting to the glass plate, cone crack was rarely ever generated.