• 대한방사선기술학회지:방사선기술과학
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• 제31권3호
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• pp.277-285
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• 2008

MRI를 이용하여 정상의 뇌량 크기를 측정한 결과 다음과 같은 결론을 얻었다. 1. 전체 대상자의 부위별 평균, 최소, 최대 1) Anteroposterior length는 평균 69.30mm, 최소 50.70mm, 최대 80.40mm이었다. 2) Diameter of genu는 평균 11.93mm, 최소 6.00mm, 최대 18.50mm이었다. 3) Diameter of mid body는 평균 7.00mm, 최소 3.40mm, 최대 10.40mm이었다. 4) Diameter of narrowing portion은 평균 4.51mm, 최소 0.80mm, 최대 9.50mm이었다. 5) Diameter of splenium은 평균 12.17mm, 최소 6.90mm, 최대 17.20mm이었다. 2. 전체 대상자의 성별에 따른 부위별 비교 1) Anteroposterior length는 남자가 여자보다 컸으며, 성별에 따라 유의미한 차이를 보였다. 2) Diameter of genu와 diameter of mid body, diameter of narrowing portion은 남자가 여자보다 컸으나 유의미한 차이는 아니었다. 3) Diameter of splenium은 남자가 여자보다 컸으며, 통계적으로도 유의미한 차이를 보였다. 3. 전체 대상자의 부위별 상관관계 1) Diameter of genu는 anteroposterior length와 통계적으로 유의미한 정적 상관관계를 보였다. 2) Diameter of mid body는 anteroposterior length, diameter of genu와 통계적으로 유의미한 정적 상관 관계를 보였다. 3) Diameter of narrowing portion은 anteroposterior length와 통계적으로 유의미한 상관관계를 보이지 않았으나 diameter of genu, diameter of mid body와 통계적으로 유의미한 정적 상관관계를 보였다. 4) Diameter of splenium은 anteroposterior length와 diameter of genu, diameter of mid body, 그리고 diameter of narrowing portion과 통계적으로 유의미한 정적 상관관계를 보였다.

• 한국통신학회논문지
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• 제30권1A호
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• pp.76-83
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• 2005

본 논문은 Diameter 기반 AAA 시스템에서 Mobile-lP 응용과 연동하는 선불 서비스의 설계 및 구현에 대하여 기술하였다. 선불 서비스 기능은 Diameter의 Credit-Control 응용에 기반 하였으며, Credit-Control 응용은 기존의 RADIUS 과금 방식이나 Diameter 베이스 프로토콜의 과금 방식이 지원하지 않는 선불 과금 서비스를 제공하기 위한 응용 기능이다. 실시간 선불 서비스 기능은 실시간 서비스 비용 결정과 서비스를 제공하기 위한 사용자의 계정 잔액 확인 절차 등과 같은 추가의 기능들을 요구한다. 본 논문에서는 위와 같은 추가의 기능들을 지원할 수 있도록, Mobile-lP 응용 서비스인 Diameter Mobile-lP 응용과 연동하는 Diameter Credit-Control 응용의 설계와 구현에 대하여 기술한다.

• 한국산림과학회지
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• 제96권2호
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• pp.160-169
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• 2007

The data used to develop distance-independent individual models for natural mixed forests were collected from 712 remeasured permanent sample plots (25,526 trees) of 10-year periodic from 1990 to 2000 in Baihe Forest Bureau of Changbai Mountains, northeast China. Based on analyzing relationship between diameter increment of individual trees with tree size, competitive status, and site condition, the diameter growth models for individual trees of 15 species growing in mixed-species uneven-aged forest stands, that have simple form, good predicting precision, and easily applicable, were developed using stepwise regression method. The main variables influencing on diameter increment of individual trees were tree size and competition, however, the site conditions were not significantly related with diameter increment. The tree size variables (lnDBH and $DBH^2$) were the most significant and important predictors of diameter growth existing in all 15 growth models. The diameter increment was directly proportional to tree diameter for each species. For the competitive factors in growth model, the relative diameter (RD), canopy closure (P), and the ratio of diameter of subject tree with maximum diameter (DDM) were contributed to the diameter increment at a certain extent. Other measures of stand density, such as basal area of stand (G) and stand density index (SDI), were not significantly influenced on diameter increment. Site factors, such as site index, slope and aspect were not important to diameter increment and excluded in the final models. The total variance explained by the final models of squared diameter increment ($R^2$) for all 15 species ranged from 35% to 72% and these results compared quit closely with those of Wykoff (1990) for mixed conifer stands. Using independent data set, validation measures were evaluated for predicting models of diameter increment developed in this study. The result indicated that the estimated precision was all greater than 94% and the models were suitable to describe diameter increment.

• 정보보호학회논문지
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• 제13권5호
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• pp.39-48
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• 2003

Diameter 프로토콜에서는 송수신되는 메시지가 아무런 문제없이 중간 경유 노드에서 변경, 삭제, 추가될 수 있다. Diameter CMS Security Application은 공개키 기반 구조를 이용하여 Diameter 응용에서 종단간 보안 기능을 제공함으로서 이러한 문제점을 해결하였다. Diameter CMS Security Application은 두 종단 노드 사이에 DSA(Diameter Security Association)을 설정하여 이후의 통신의 안전성을 보장하도록 하고 있다. 그러나 시스템 장애 등의 이유로 한 노드가 DSA 정보를 분실하였을 경우, 이 Application을 사용한 두 노드 사이의 안전한 통신에는 문제가 발생하게 된다. MIP(Mobile IP)와 같은 응용에서는 이러한 문제로 사용자 등록이 불가능하여 서비스가 이루어지지 못할 수도 있다. 따라서 본 논문에서는 이러한 경우 DSA를 재설정 할 수 있는 방법을 제시하고 이 해결책을 실제 구현한 결과를 보인다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.600-604
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• 2001

The relation between the aerodynamic diameter and some morphological parameters was studied for flame-generated aggregates. $SiO_{2}$ aggregates were generated from $SiCl_{4}$ in premixed methane/air flames. These aggregates were sampled and classified according to their aerodynamic diameter by a cascade impactor; moreover, computer program was developed and tested to find the equivalent area diameter and the fractal dimension of the aggregates. We calculated the parameters from the digitized images of the aggregate TEM micrographs. The aerodynamic diameters of the sampled aggregates were larger than $0.4{\mu}m$ in this experiment. In most cases, fractal dimension of their projection image was very close to 2.0 for these large aggregates. It was found that the equivalent area diameter of these aggregates was approximately three times larger than the Stokes' diameter of them.

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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• pp.1761-1769
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• 2007

This experiment was conducted to determine the extent to which susceptibility to cortisol-induced follicle shutdown is influenced by fleece phentotype. Twenty Finewool (10 sheep low fibre diameter, low coefficient of fibre diameter-LL and 10 low fibre diameter, high coefficient of variation of fibre diameter-LH) and twenty Strongwool (10 low fibre diameter, low coefficient of variation of fibre diameter-HL and 10 high fibre diameter and high coefficient of variation of fibre diameter-HH) sheep of 9 months of age were individually penned in an animal house and were injected intramuscularly with an aqueous suspension of hydrocortisone acetate at a rate of 1.42 mg/kg body weight for a period of two weeks. Fibre diameter was measured from clipped tattooed patch wool samples. Follicle activity was measured by histological changes in skin biopsies taken weekly. Blood samples were collected at two-week intervals and plasma cortisol measured. Increased plasma cortisol concentration significantly (p<0.05) reduced clean wool production and mean fibre diameter dropped to its lowest level four weeks after commencement and two weeks after the cessation of cortisol injection. Elevation of plasma cortisol concentration significantly (p<0.0001) increased the percentage of inactive follicles two weeks after injection started. High fibre diameter groups (Strongwool sheep; i.e. HL+HH) had significantly (p<0.0001) higher percentage of follicle shutdown than low fibre diameter groups (Finewool sheep; i.e. LL+LH). Average percentage of shutdown follicles for Finewool (LL+LH) and Strongwool (HL+HH) Merino sheep was $9.8{\pm}0.9$ and $13.5{\pm}0.9$ respectively. Shutdown of primary follicles was more pronounced in Finewool than Strongwool sheep. There was no significant effect of coefficient of variation of fibre diameter on propensity to follicle shutdown induced by exogenous cortisol. It is concluded that elevation in plasma cortisol concentration is inhibitory to the normal activity of follicles in Strongwool sheep but that variation in fibre diameter has little or no effect.

• 한국입자에어로졸학회지
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• 제19권4호
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• pp.155-164
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• 2023

APS (Aerodynamic Particle Sizer) and OPC (Optical Particle Counter) have been widely used to real-time measurement of indoor and outdoor aerosols. The APS measures the size distribution based on an aerodynamic diameter, while the OPC uses optical diameter to measure the size distribution of aerosols. Since obtaining a size distribution based on aerodynamic diameter is important to understand aerosol characteristics, lots of researcher had been developed experimental equations which can convert optical diameter into aerodynamic diameter. However, previous studies have conducted repeated experiments on particles having a single diameter. In this study, an experimental method of converting optical diameter into aerodynamic diameter through a single experiment was presented. The collection efficiencies of an axial cyclone were measured using APS and OPC at the same time, and the correlation equation between aerodynamic diameter and optical diameter was driven through a theoretical model. Using the proposed method, the size distribution of NaCl particles measured by OPC showed a high correlation with the size distribution obtained by APS (0.93 of R-squared value). In the tests conducted on ISO A1, A2, and A4 test particles, the converted OPC size distribution tended to be similar to the APS size distribution, and for each of test particles (ISO A1, A2, and A4), the R-squared values for the APS particle size distribution were 0.75, 0.86, and 0.89, respectively.

• 대한치과보철학회지
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• 제41권2호
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• pp.169-181
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• 2003

Statement of problem : The survival rate of wide diameter implants was lower than of 3.75-mm implants in some clinical researches. Purpose : The purpose of this study was to investigate the influence of implant diameter on the osseointegration of implants in the rabbit femoral condyle and tibial metaphyses by means of removal torque measurements and histomorphometric analysis. Material and Method : Ten adult New Zealand White rabbits were used in this study Two 3.75-mm diameter implants were inserted through one cortical layer in the tibial metaphyses and one 3.75-mm diameter implant was inserted in the femoral condyle. 5.0-mm diameter implants were inserted in the other leg in the same manner. A total of 60 implants (3.75-mm diameter implants:30 : 5.0-mm diameter implants:30) were installed. After a healing time of 4 and 12 weeks, the peak removal torque values required to shear off the implants were recorded. From the removal torque values (Ncm) obtained, the mean shear stress ($N/mm^2$) was calculated. And the percentage of direct bone-to-implant contact and the percentage of bone area inside the thread were measured by Kappa Image Base-metreo. The Student's t-test was undertaken for statistical analysis (p<0.05). Results : The removal torque value of 5.0-mm diameter implants was higher than of 3.75-mm diameter implants (p<0.05). The difference of shear stress value between 3.75-mm and 5.0-mm diameter implants was not statistically significant (p>0.05). The percentage direct bone-to-implant contact had no statistical difference between two groups (p>0.05). The percentage of bone area inside the thread had no statistical difference between two groups (p>0.05). Conclusion It is concluded that the quality f osseointegration is not influenced by increasing implant diameter.

• Advanced Composite Materials
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• 제16권3호
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• pp.245-258
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• 2007

The single-modal Weibull model has been assessed on Tyranno ZMI Si-Zr-C-O fiber if a set of shape and scale parameters accurately reproduced the effect of the size of the diameter on strength. The tensile data of a single fiber have been divided into two expedient groups as 'small diameter' group and 'large diameter' group in deriving the parameters, which should be consistent if the Weibull model accurately reproduced the size effect. However, the derived Weibull parameters were inconsistent between the two groups. Thereby the authors have concluded that the parameters of the single-modal Weibull model are dependent on the fiber diameter, so that the model is inadequate to reproduce the strength size effect. On the other hand, Weibull parameters were found consistent between the two groups by excluding the data of 'large mirror zone' sample, which was defined as the sample around 10% mirror zone area of the fracture surface. What is more, the exclusion reduced the strength variance more drastically in the 'large diameter' group than in the 'small diameter' group, even though the 'large mirror zone' samples were found identical in the percentage between the two groups. The authors therefore conclude that diameter limitation to the 'small diameter' group level can lead to drastically less distributed strength values than the estimated strength through the Weibull scaling on the present Tyranno ZMI Si-Zr-C-O fiber.

• 대한기계학회논문집
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• 제7권3호
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• pp.313-318
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• 1983

It is required in designing a spot welding to get in advance an estimated figure of nugget diameter. A method of estimating nugget diameter of low carbon steel sheets is suggested in tesms of utilizing elastic calculation in theory and of making a sectional observation of specimen of spot welding in experiment. The resultant findings are summarized as follows: 1) A contact diameter of sheet, 2.gamma.$_{o}$=d sub e/+(1.1)t, wheer de is the electrode tip diameter and t is the thickness of sheets. 2) The practical measurement of the nugget diameter reveals that $d_{n}$=(1.05) $d_{e}$+(0.9)t, and $d_{b}$ is less by 0.8-4.3% than 2.gamma.$_{o}$. 3) The more $d_{n}$ is as compared with t, the less the difference between a theoretical value and an experimental value is. 4) In the spot welding of thin steel sheets less than 3mm in thickness that are commonly used in sheet metal works, the contact diameter equals the nugget diameter. In this case, either the theoretical or experimental approach can be used for estimating the nugget diameter.meter.ter.r.