• 대한치과보철학회지
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• 제36권6호
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• pp.888-899
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• 1998

In-Ceram system is one of contemporary esthetic all ceramic restorations and has relatively high flexural strength. The purpose of this study was to evaluate the marginal fidelity according to type of resin cement and measuring position, and to evaluate fracture strength according to type of resin cement. In this study, twenty seven In-Ceram crowns were fabricated on the metal master die of prepared maxillary right central incisor and devided into three groups. All specimens were cemented with Panavia 21 (group PV), Super-bond (group SB) and Lute-it (group LI) on the metal master die. After cementation, specimens were measured marginal gap between the margin of the In-Ceram crown and the finishing line of metal master die by using a stereomicroscope (SZ-ST, Olympus, Japan). Marginal gaps were recorded at the labial, lingual, mesial and distal measuring points on the metal master die. For the mesurement of fracture strength, lingual surfaces of cemented specimens were loaded at a distance of 1mm from incisal edge by using the Autograph S-2000 (Shimadzu, Japan). The results of marginal fidelity and fracture strength were statistically analyzed with the SPSS version 8.0 programs. The results of this study were as follows: 1. In comparison of marginal fidelity according to the measuring points, there was no significant difference. 2. The marginal fidelity according to the type of resin cement was decreased in order of group $LI\;(63.75{\mu}m),\;SB\;(77.78{\mu}m),\;PV\;(86.53{\mu}m)$, and there was significant difference between group LI and PV (p<0.05). 3. The fracture strength according to the type of resin cement was showed descending order of group $LI\;(60.00kg/cm^2),\;SB\;(56.80kg/cm^2),\;PV\;(56.11kg/m^2)$, but there was no significant difference.

• 대한치과교정학회지
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• 제25권4호
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• pp.487-495
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• 1995

본 연구는 T-Scan system과 두부방사선 계측사진을 이용하여 정상교합자와 전치부 개방교합자의 최대교합력을 비교하고 안면골격형태, 치아접촉수 및 위치와 교합력과의 상호관계를 비교분석하기 위하여 시행하였다. 연구대상은 25명의 정상교합자와 14명의 전치부 개방교합자로 구성되었다. 이 연구로부터 얻어진 결과는 다음과 같다. 1. 전치부 개방교합자의 최대교합력은 정상교합자군에 비해 적었다. 2. 전치부 개방교합군에서 SN/MP, FMA, PP/MP는 최대교합력과 역상관관계를 보였다. 3. 전치부 개방교합군에서 교합평면에 대한 하악 제1대구치의 근심경사도가 증가할수록 교합력은 감소하였다. 4. 정상교합군과 전치부 개방교합군 모두에서 치아접촉점이 증가할수록 교합력은 증가하였다. 5. 전치부 개방교합군과 정상교합군의 정량적 감압중심점은 모두 제1대구치 부위에 위치하였다.

• 정보처리학회논문지B
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• 제11B권3호
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• pp.289-296
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• 2004

일반적인 워터마킹 기술들은 영상의 특성을 고려하지 않은 채 신체 책인 영상에 워터마크를 삽입하는 경우가 많다 본 논문에서는 워터마킹 알고리즘을 웨이브렛을 기반으로 구현을 하였으며, 견고한 워터마크 삽입을 위해 Multi-Threshold Watermark Coding(MTWC)의 원리에 기초하여 Region of Interest(ROI)라고 불리우는 영상의 영역에 큰 계수를 찾아 워터마크를 삽입하게 된다. 이때 Human Visual System(HVS)을 이용하여 견고성과 비가시성의 향상을 도모하였다. 워터마크 삽입대역은 중주파 대역에 삽입을 하게 되는데 중주파 대역에 삽입한 워터마크는 어떠한 영상 처리과정 후에도 높은 비율의 추출을 보였으며, 워터마크가 삽입된 영상의 왜곡정도도 다른 대역보다 상대적으로 적게 나타나므로 중주파 대역에 워터마크를 삽입하였다. 워터마크는 의사 랜덤 시퀀스(Pseudo Random Sequence)로 구성되어 있고 워터마크의 검출은 Cox의 유사도 측정식을 이용하여 워터마크의 삽입여부를 판단한다

• 한국환경보건학회지
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• 제9권2호
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• pp.75-81
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• 1983

The Biochemical Oxygen Demand(BOD) indicates that microbes are proliferating or that oxygen is being spent by breathing action when examining water under the same aerobic condition. In this research of the mesurement of BOD are the poisonous elements of heavy metal ions such as Cu-ion, Cr-ion, Pb-ion and Zn-ion. They exert an unfavorable influence in the analysis of BOD and research was performed to provide certain data of minimum negative influence by the poisonous matters. The results of the research confirm that heavy metal ion(Cu, Cr, Pb, Zn) do direct an influence upon the normal growth of aerobic microbes in actual tests of chemical analysis of portable water or sewage. The most critical concentration for a negative effect on lowering oxygen quantity and disturbing the aerobic mocrobes normal growth was found to be 0.01 mg/l. Therefore, test results are not valid if the heavy metal concentration is to or greater than 0.0mg/l, To improve comprehension through out the research the author uses the following abbreviations: 1. The Cu-ion is to be excluded before experimental analysis if it is over 0.01mg/l inorder to obtain a real value for the BOD. 2. The Cr-ion is to be excluded before experimental analysis if it is over 0.01mg/l in order to obtain a real value for the BOD. 3. The Pb-ion is to be excluded before experimental analysis if it is over 0.01mg/l in order to obtain a real value for the BOD. 4. The Zn-ion is to be excluded before experimental analysis if it is over 0.01mg/l in order to obtain a real value for the BOD.

• 대한핵의학회지
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• 제19권1호
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• pp.77-81
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• 1985

There are several methods for measurement of cerebral blood flow. A method using Tc-99m DTPA which was injected via antecubital vein and monitored extracranially with gamma camera is described here. In this method, the brain scan and CBF mesurement were performed with scan and CBF were usually studied separately. The results were as follow: 1) Total candidates were 53, male 34 and female 19, who have no evidence of neurologic, cardiac or kidney problems. 2) By this method, the normal CBF of Korean was $54.12{\pm}6.49ml/min/100g$ of brain tissue. 3) The CBF of male was $54.06{\pm}5.9ml/min/100g$ of brain tissue, female was $54.89{\pm}6.51ml/min/100g$, so there was no definite sex difference. 4) The CBF under 10 years of age was $54.12{\pm}2.5ml/min/100g$, $11\sim20years$ of age was $52.33{\pm}6.1ml/min/100g$, $21\sim60years$ of age was $52.86{\pm}5.06ml/min/100g$, and over 61years of age was $55.43{\pm}4.84ml/min/100g$, so there was no significant difference of CBF by age.

• 치과방사선
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• 제24권2호
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• pp.361-368
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• 1994

Radiographic planning is needed for implant placement in order to determine implant length, jaw bone volume, anatomical stucture and so on. Radiographic examination includes conventional radiography, conventional tomography and CT scan. The most accurate mesurement can be obtained from CT scan. For the cross-sectional view of mandible, CT scan reconstruction is generally needed. But the cross-sectional view of mandible can be reformed by personal computer. This study was performed to examine the clinical usefulness of reformed image using personal computer in comparison with CT scan reconstructed image. CT axial slices of 4 mandibles of 4 volunteers were used. Digital imaging system was composed of Macintosh Ⅱ ci computer, high resolution Sony XC-77 CCD camera, Quick Capture frame grabber board and 'NIH Image' program. Seven reconstructed cross-sectional images within CT machine(CT group) were obtained. And seven reformed cross-sectional images(PC group) after digitization of CT axial slices into the personal computer were obtained. PC group was compared with CT group in the objective and subjective aspects. The results were as follow: 1. Measurement of mandibular height & width in both group showed insignificant difference(P>0.05). 2. Subjective assessment of the mandibular canal in both group showed insignificant difference(P>0.05). 3. Image reformation using personal computer could provide panoramic view, which could not be obtained in CT scan reconstruction.

• 상하수도학회지
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• 제29권5호
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• pp.543-550
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• 2015

In this study, using soil brick with combined effective microorganisms and emergent plants was identified which it can increase the effect of conservation and improvement of water. Lab-test was consist of four kind of reactors and each of reactors were A(rawwater), B(soil brick), C(emergent plant) and D(soil brick+emergent plant). Iris pseudoacorus, Phargmites australis, Typha angustifolia and Zizania latifolia were used for emergent plant. Evaluation of application on various environment were performed on agricultural waterway and pond. The pH measurement test of soil brick was performed due to evaluate whether a strong alkaline water flows out of the soil brick. Result of lab-test, removal efficiency of D was better than removal efficiency of A presenting 20.9%, 27.9% 21.5%, 33.8% and 58.4% for $COD_{Cr}$, $BOD_5$, TN, TP and TSS respectively. Removal efficiency of soil brick on agricultural waterway was revealed to be 49.5%, 45.0%, 43.7%, 37.3% and 28.6% for $COD_{Cr}$, $BOD_5$, TN, TP and TSS respectively. And removal efficiency of soil brick on the pond was revealed to be 12.7%, 10.5%, 9.32%, 10.4% and 36.3% for $COD_{Cr}$, $BOD_5$, TN, TP and TSS respectively. Result of pH measurement test of soil brick was neutral which was about 6 to 8.

• 대한가정학회지
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• 제25권1호
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• pp.1-10
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• 1987

The purpose of this study was to investigate the relationships between demographic variables and seven aspects of clothing behavior of adult males, and to attempt to develop the measurement of men's clothing behavior. Age was ranked by five gradation (20∼60 ages) and socio-economic status was divided into three categories (high, middle, low) based on the subjects' education, occupation and economic status. Six aspects of clothing comfort, satisfaction, status symbol, conformity, fashion interest and clothing acceptance I were assessed with Koh's, Chung's and Lee's questionnaires. Clothing acceptance by line-drawing of clothing syles representing different levels of formality for occasions designed to measure the awareness of appropriate clothing category of business suits. The questionnaires in this study were administered to a sample of men living in Seoul. The sample was drawn by the random-cluster sampling method. The data from 362 respondants were analysed. To determine the internal validity of clothing behavior mesurement, factor analysis was computed, whereas to determine the reliability, Cronbach's alpha was calculated. The statistical methods adopted were correlation, one-way ANOVA, and multiple regression. The results obtained in this study were as follows: 1) As for clothing behavior instruments, items dealing with status symbol and fashion nterest were proved to be satisfactory as a measurement of adult males. Eight factors emerged on clothing acceptance Ⅱ, most of which were representing unappropriate clothing choice for occasion. 2) Demographic variables were significantly related to the adult males' clothing behavior. (1) Age was positively related to clothing conformity but negatively to fashion interest. (2) Socio-economic status was positively related to clothing satisfaction, status symbol, and fashion interest but negatively to clothing confort. (3) When age was controlled, socio-economic status was negatively related to comfort in 40∼50s age group only, and negatively related to clothing conformity in 20∼30s age group only. (4) Four subscales of clothing acceptance Ⅱ representing unappro-priate clothing practice for selected occasions were negatively related to age and/or socio-economic status.

• 수산경영론집
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• 제49권1호
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• pp.67-89
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• 2018

In fisheries, as well as in other natural resource-based industries, there is difference between profit and rent. The former is a basic indicator for gauging the business performance of firms, while the latter is for the evaluation of the contribution of resources and industry to economic welfare. Put simply, resource economists are mainly concerned about rent, including pure resource rent and producer surplus (intra-marginal rent [IMR]). In other hand, business economists are mainly concerned about the profitability of the firms comprising the industry. In the academic literature, there are not always clear definitions of the profit and rent concepts and their use in actual analyses. This article will mainly discuss and clarify differences and similarities in profit and rent concepts. In the classical fisheries economic model with one-dimensional homogenous effort and a constant cost per unit of effort, no rent exists in open-access equilibrium. A simple change in this model, for example by introducing heterogeneous effort, opens it to the existence of rent, specifically IMR, at open-access equilibrium. We estimated resource rent and profit from the data using SNA(system of national accounts) and accounting data methods. RR(resource rent) is composed of value-added, compensation of employees, consumption of fixed capital and normal profit in SNA. RR(resource rent) is composed of EBT, Depreciation of fishing rights, financial costs of fishing rights and calculated interests on equity in accounting data methods. We found that the result of two methods is equal. RR is composed of excess profit, rent and interest expenses. In Korea, the magnitude of RR and profit is not different significantly.

• 대한전자공학회논문지
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• 제21권5호
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• pp.46-54
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• 1984

3μm 게이트 길이를 가지는 n-well CMOS 공정이 개발되었고 이의 응용 가능성을 검토하였다. Thres-hold 전압은 이온주입으로 쉽게 조절할 수 있으며, 3μm 채널 길이에서 short 채널 효과는 무시할 수 있다. Contact 저항에 있어서 Al-n+ 저항값이 커서 VLSI 소자의 제작에 장애 요인이 될 것으로 보인다. CMOS inverter의 transfer 특성은 양호하며, (W/L) /(W/L) =(10/5)/(5/5)인 89단의 ring oscillator로부터 구한 게이트당 전달 지연 시간은 3.4nsec 정도이다. 본 공정의 설계 규칙에서 n-well과 p-substrate에 수 mA의 전류가 흐를 때 latch-up이 일어나며, well 농도와 n+소오스-well간의 간격에 크게 영향을 받는다. 따라서 공정과 설계 규칙의 변화에 따른 latch-up 특성에 집중적인 연구가 필요할 것으로 사료된다.