• 한국음향학회지
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• 제31권8호
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• pp.580-589
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• 2012

이 논문에서는 휴대용, 또는 저가형 초음파진단기에 비교적 고급 기능인 도플러 갭 필링 모드를 적용하고자할 때 적합한 알고리즘들을 찾아보았고, 그 결과 미러링 기반, 또는 자기회귀 모델 기반의 알고리즘들을 찾을 수 있었다. 또, 계산량이 지나치게 많아지지 않는 범위 내에서, 그러한 알고리즘들의 성능의 문제점을 보완하여 더욱 개선시켰다. 수정된 알고리즘들은 인공적으로 발생시킨 도플러 신호 및 실제 초음파장비를 써서 인체로부터 획득한 도플러 데이터를 써서 시뮬레이션 및 실험을 함으로써 유효성을 확인하였다.

• 한국의류학회지
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• 제16권4호
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• pp.349-355
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• 1992

Comfortable sleeping largely depends on human mental state, physical condition, the temper. ature and humidity in bedrooms, and qualities of quilt and bedcover. Of the qualities of quilt, thermal insulation effect plays the most important role in keeping bedroom in ample temperature and preventing human body from giving off heat. In the present study, which is a sequel study to research on the thermal insulation effect, the real-size quilts with the following items of filling materials in them are designed to research on the variation of each item, and to measure the effect of the weight variation in inner covers on the thermal insulation effect of quilts, the results are as follows: 1. The coefficient between the weight of filling materials and the thermal insulation effect of quilt is shown to be a significant $0.91\~0.97$. 2. The thermal insulation effect of the quilts with in size of $0.5\;Kg/m^{2}$ is surveyed to be high in order down > polyester > cotton > wool. 3. The effect of the texture of inner covers on the thermal insulation effect of quilt is shown to be ignorably low. 4. The weight of filling materials is shown to be in correlation with the thermal insulation effect of quilts, and the estimated regression line has been obtained.

• 한국재료학회지
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• 제16권11호
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• pp.698-704
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• 2006

In this study, the effect of chill layers occurred in shot sleeve on the molten metal filling was analyzed through computer simulation. The behavior of chill layers with temperature variation of shot sleeve set from 200 to $280^{\circ}C$ was also investigated. The simulation results showed the chill layers set in the in-gates during the injection process change the main filling direction and cause turbulent flow pattern, resulting in porosities inside the castings. The amount of chill layers with the increasing temperature of shot sleeve was considerably reduced. Particularly, at the setting temperature of $280^{\circ}C$ by heat control unit, the biggest reduction in chill layers, excellent trimmed surface and the highest density were achieved, suggesting that as the optimal sleeve condition in aluminum high pressure diecasting, especially for highly complex parts like valve body.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -1
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• pp.38-41
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• 2002

Many scientifc applications include manipulation of data points tying in a space. We describe a method, based on sector labeling to generate a space-filling curve for partitioning such given data points. Our method is straightforward and flexible, equipping a one-one correspondence between point-values on the curve and data points in space in more efficient than designated methods found in the literature. It is widely believed that the Hilbert curve achieves the desired properties on linear mappings due to the locality between data points. Therefore we focus on the Hilbert curve since, later on, we identify it as the most suitable for our application. We demonstrate on using our method for the data particles of an n-body simulation that based on Barnes-Hut algorithm.

• 한국의류학회지
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• 제26권5호
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• pp.691-702
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• 2002

The purpose of this study was to provide basic information on the propriety of the ready to wear garment sizes of Tween Generation(ages from 5th grade to 8th grade) who has different clothing preferences in color, styles, and design and also different body sizes and shapes from younger and older students. The objectives of the study were to ascertain (a) the body figure changes occurring during Tween Generation; (b) the coverage of manufactures'garment sizes. The body measurements of elementary school students(5th & 6th grades) and junior high school students(7th & 8th grades) provide the basic statistics for this study. The mean differences of each size within each figure type are compared by using t-teats. The differences in various manufacturers'apparel sizing and figure size are investigated. Also the body measurements and the apparel sizes of the manufacturers are compared in order to evaluate the suitability of the garment size. Results indicate that the body type factors are different in each age group. And manufactures'sizes come out to be much smaller than the actual body measurements. Young casual wear can cover junior high school students satisfactorily but for elementary school students, because of low drop-value, the overall satisfaction with filling is low.

• 대한기계학회논문집A
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• 제36권12호
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• pp.1577-1583
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• 2012

횡방향 관통 효율 강화 탄체(PELE)는 기폭장치가 없는 새로운 개념의 발사체이다. PELE 는 배면이 닫혀있는 고밀도 피복과 저밀도 충전재로 구성되어있다. PELE 의 폭발 특성을 연구하기 위해 AUTODYN-3D code 를 이용하여 발사체와 표적체의 모델을 구축하였다. PELE 의 의해 알루미늄-2024 합금 표적체를 천공하는 과정을 시뮬레이션으로 구현하였으며 또한 다양한 내부 충전재에 의해 분산되는 표적체의 파편 특성도 연구하였다. PELE 파편의 유한요소해석은 AUTODYN-3D code 의 추계학적 파괴기준을 사용하여 구현되었다. 내부 충전재의 팽창으로 인해 파편은 속도를 얻으며 횡방향으로 분산된다. 따라서 손상영역의 범위가 증강한다. 관통 및 횡방향 분산 과정에서 생성되는 파편은 내부 충전재의 충격 압력에 따라 그 양과 형태가 다른 것으로 나타났다.

• Geomechanics and Engineering
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• 제13권2호
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• pp.195-215
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• 2017

This paper proposes gob-side entry retaining by roof break and filling in thick-layer soft rock conditions based on the thick-layer soft rock roof strata migration law and the demand for non-pillar gob-side entry retaining projects. The functional expressions of main roof subsidence are derived for three break roof direction conditions: lateral deflection toward the roadway, lateral deflection toward the gob and vertically to the roof. These are derived according to the load-bearing boundary conditions of the main roadway roof stratum. It is concluded that the break roof angle is an important factor influencing the stability of gob-side entry retaining surrounding rock. This paper studies the stress distribution characteristics and plastic damage scope of gob-side entry retaining integrated coal seams, as well as the roof strata migration law and the supporting stability of caving structure filled on the break roof layer at the break roof angles of $-5^{\circ}$, $0^{\circ}$, $5^{\circ}$, $10^{\circ}$ and $15^{\circ}$ are studied. The simulation results of numerical analysis indicate that, the stress concentration and plastic damage scope to the sides of gob-side entry retaining integrated coal at the break roof angle of $5^{\circ}$ are reduced and shearing stress concentration of the caving filling body has been eliminated. The disturbance of coal mining to the roadway roof and loss of carrying capacity are mitigated. Field tests have been carried out on air-return roadway 5203 with the break roof angle of $5^{\circ}$. The monitoring indicates that the break roof filling section and compaction section are located at 0-45 m and 45-75 m behind the working face, respectively. The section from 75-100 m tends to be stable.

• 핵의학기술
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• 제20권1호
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• pp.24-27
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• 2016

방광 주변에 병변이 있는 환자의 경우 소변의 충만으로 방광 주변에 병변 평가의 영향이 있기 때문에 방광 팬텀을 직접 제작하여 방광 충만 여부에 따라 주변 병변이 미치는 영향을 평가하고자 한다. Biograph mCT40 (siemens, germany)을 사용하여 6개의 insert에 각각 14.8 MBq ($400{\mu}Ci$), Background 110 MBq (3 mCi), 방광에 74 MBq (2 mCi)를 주입하였다. NEMA IEC body 팬텀을 이용하여 고무풍선을 방광으로 대체하고 6개의 insert를 방광 주변 병변으로 설정하고, %BV, SUV, peak count rate의 영상평가 인자를 이용하여 비교하였다. % BV는 방광으로부터 거리가 멀수록 감소하는 것을 확인하였다. 방광으로부터 거리에 따른 hot sphere는 방광의 충만여부에 따라 $7.8{\pm}3.8%$의 SUV 차이가 났다. 방광으로부터의 거리가 0.4 cm 이하까지 방광을 비웠을 경우 평균 카운트가 약 14% 높게 측정되었으며, true count는 38% 감소한 반면, single count는 44%, random count는 61% 감소하였다. 그리고 그 이상의 거리에서는 큰 변화를 보이지 않았다. 그러므로 방광에 찬 소변이 주변 병변에 영향을 미치는 것을 확인하였고, 방광으로부터 거리가 가까울수록 영향이 크다는 것을 확인하였다. 방광이나 방광 주변에 병변이 있는 환자뿐만 아니라 PET-CT 검사를 하는 모든 환자에 있어 방광을 비우고 검사를 하는 것이 정확한 검사를 하는데 도움을 제공해 줄 것으로 사료된다.

• 대한치과의사협회지
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• 제18권2호통권131호
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• pp.115-119
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• 1980

The purpose of this study was to observe clinical behavior on a national dispersant amalgam alloy, KISTCAP which newly developed by the KIST (Korea Instute for Science and Technology) in Korea. The results were as follows: 1. There was no significant difference in manipulating between the above mentioned alloy and the conventional lathe cut alloy. 2. The condensation pressure for this alloy was relatively less than that of conventional one. 3. More time was needed to polish the surface of this amalgam filling body than the conventional one. 4. No notable difference was seen in the over-all clinical behavior between the Whitecap and kistcap, except the latter one showed a little more tendency in redish color.

• Imaging Science in Dentistry
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• 제47권4호
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• pp.281-284
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• 2017

Foreign body granulomas can develop after the injection of various cosmetic filling materials into the facial area to flatten wrinkles. Clinically, reactive lesions are easily mistaken for soft-tissue neoplasms or cysts. This report presents a case of foreign body granuloma in a 52-year-old female patient complaining of a painless swelling in the nasolabial region. Both clinical and histological features are described, underscoring the diagnostic role of magnetic resonance imaging findings.