• 대한치과기공학회지
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• 제41권4호
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• pp.287-293
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• 2019

Purpose: To evaluate the accuracy of the 3D printed die models and to investigate its clinical applicability. Methods: Stone die models were fabricated from conventional impressions(stone die model; SDM, n=7). 3D virtual models obtained from the digital impressions were manufactured as a 3D printed die models using a 3D printer(3D printed die models;3DM, n=7). Reference model, stone die models and 3D printed die models were scanned with a reference scanner. All dies model dataset were superimposed with the reference model file by the "Best fit alignment" method using 3D analysis software. Statistical analysis was performed using the independent t-test and 2-way ANOVA (α=.05). Results: The RMS value of the 3D printed die model was significantly larger than the RMS value of the stone die model (P<.001). As a result of 2-way ANOVA, significant differences were found between the model group (P<.001) and the part (P<.001), and their interaction effects (P<.001). Conclusion: The 3D printed die model showed lower accuracy than the stone die model. Therefore, it is necessary to further improve the performance of 3D printer in order to apply the 3D printed model in prosthodontics.

• Journal of the Korean Data and Information Science Society
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• 제19권3호
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• pp.893-901
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• 2008

The disconfirmation paradigm is the earliest researched and the most deeply researched of all the paradigms in marketing. Disconfirmation paradigm deals with the influence of expectation, perceived product performance, and the discord between the two on consumer satisfaction. The GAP-Model is based on the disconfirmation paradigm that tries to understand the effect of the gap between before purchase expectations and after purchase perceptions of the product performance on dependent variables such as customer satisfaction. The purpose of this research is to test whether regression coefficients of a P-Model(performance only model), an E-Model(expectation only model) and GAP(P-E)-Model are equivalent in explaining service value and loyalty. The Chow's F-Test is used to test the excellence of the 3 models. As a result of comparison and analysis, P-Model showed more excellence of service value and loyalty than E-Model or GAP-Model.

• 한국산업융합학회 논문집
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• 제19권3호
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• pp.109-124
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• 2016

The objective of this paper is to find the density, stiffness, and strength of truss-wall diamond corrugation model combined with pinwheel truss inside space. The truss-wall diamond corrugation (TDC) model is defined as a unit cell coming from solid-wall diamond corrugation (SDC) model. Pinwheel truss-wall diamond corrugation (P-TDC) model is made by TDC connected with pinwheel structure inside of the space. Derived ideal solutions of P-TDC is based on truss-wall and pinwheel truss model at first. And then it is compared with Gibson-Ashby's ideal solution. To validate the ideal solutions of the P-TDC, ABAQUS software is used to predict the density, strength, and stiffness, and then each of them are compared to the ideal solution of Gibson-Ashby with a log-log scale. Applied material property is stainless steel 304 because of having cost effectiveness. Applied parameters for P-TDC are 1 thru 5 mm diameter within fixed opening width as 4mm. In conclusion, the relative Young's modulus and relative yield strength of the P-TDC unit model is reasonable matched to the ideal expectations of the Gibson-Ashby's theory. In nearby future, P-TDC model is hoped to be applied to make sandwich core structure by advanced technologies such as 3D printing skills.

• Nutrition Research and Practice
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• 제16권2호
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• pp.205-216
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• 2022

BACKGROUND/OBJECTIVES: While many obesity studies have pointed out the importance of meal regularity, few have conducted empirical analyses using data from food diaries. We examined the association between meal regularity (i.e., meal time regularity [MTR] and calorie intake regularity [CIR]) and weight loss. SUBJECTS/METHODS: We collected food diary data from 637 women who had participated in commercial weight loss programs for 28-168 days (4-24 weeks). This study defined "meal regularity" in terms of two concepts: MTR and CIR. MTR refers to how regularly people eat their meals (i.e., at certain times each day), whereas CIR refers to how regularly people consume a certain amount of calories at each meal. We conducted multiple regression analyses. RESULTS: MTR (model 1: β = -2,576.526, P < 0.001; model 2: β = -1511.447, P < 0.05; model 3: β = -1,721.428, P < 0.05) and CIR (model 1: β = -1,231.551, P < 0.01; model 2: β = -2,082.353, P < 0.001; model 3: β = -1,343.490, P < 0.01) turned out to be significant determinants of the amount of weight loss in breakfast, lunch, and dinner contexts. While meal regularity (i.e., MTR and CIR) was significantly associated with weight loss, daily calorie intake from meals was not significantly associated with the amount of weight loss (model 1: β = 0.13, P > 0.05; model 2: β = 0.11, P > 0.05; model 3: β = 0.14, P > 0.05). Subjects who consumed an equal amount of calories per meal throughout the day lost more weight than those who did not (model 4: β = -3,675.51, P < 0.001). CONCLUSIONS: Eating each meal (i.e., breakfast, lunch, and dinner) at a certain time every day may increase weight loss success. Also, consuming the same amount of calories at each meal may help weight loss success.

• Journal of Radiation Protection and Research
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• 제17권1호
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• pp.21-30
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• 1992

KCCH cyclotron neutron(30cCy/min) 및 $^{60}Co\;{\gamma}-ray(210cGy/min)$를 시험관내의 정상인체 말초혈액임파구에 조사하여 염색체이상(dicentric 및 centric ring)을 관찰하고 이의 선량-반응관계식을 linear model$(Y=K_1D+a)$, power-law model$(Y=K_2D^n)$, quadratic model$(Y=K_3D^2)$ 및 linear-quadratic model$(Y={\alpha}D+{\beta}D^2)$을 사용하여 구하고 이들 model중 염색체이상의 측정치와 가장 일치하는 관계식을 근거로 하여 ${\gamma}-ray$에 대한 neutron의 relative biological effectiveness (RBE)를 산출하였다. 염색체 이상(dicentric plus centric ring)의 발생분포는 ${\gamma}-ray$의 경우 linear model(P=0.067)을 제외한 power-law model$[Y=(5.81{\pm}1.96){\times}10^6D^{1.93+0.06},\;P=0.931]$, quadratic model$[Y=(3.91{\pm}0.09){\times}10^{-6}D^2,\;P=0.972]$ 및 linear-quadratic model $[Y=(6.55{\pm}6.83){\times}10^{-5}D+(3.72{\pm}0.22){\times}10^{-6}D^2$ P=0.922]에 적합하였다 neutron의 경우 linear model $(Y=(6.12{\pm}0.17){\times}10^{-3}\;D-0.22,\;P=0.987]$에 가장 일치하였고 quadratic model (P<0.005)을 제외한 power-law model $[Y=(5.36{\pm}3.02) {\times}10^{-4}D^{1.42+0.11},\;P=0.601]$ 및 linear-quadratic model $[Y=(2.43{\pm}0.70){\times}10^{-3}D+(1.21{\pm}0.39){\times}10^{-7}D^2,\;P=0.415]$에 비교적 적합하였다. 세포당 0.1-1.5개의 염색체이상을 나타내는 neutron의 ${\gamma}-ray$에 대한 RBE는 $2.714{\pm}0.408$이었다.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2004년도 춘계 학술발표회 논문집
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• pp.395-400
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• 2004

국내 차세대 원전인 APR 1400 원전의 원자로 냉각 계통(Reactor Coolant System)을 대상으로 하여 표준 데이터 모델 기반의 데이터 저장소를 구축하였다. 또한 구축한 데이터 저장소를 기반으로 웹을 통해 해당 계통 및 계통에 포함되어 있는 장비의 속성정보를 검색할 수 있으며, 마이크로스테이션이라는 설계 틀에서 2차원 도면인 P&ID와 해당 P&ID와 연관된 3차원 CAD를 연계시킴으로써 P&ID를 바탕으로 건설한 원전 플랜트를 3차원 CAD 모델을 통하여 해당 계통의 실제 레이아웃(Layout)을 확인할 수 있도록 하는 프로토타입 시스템을 개발하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 가을 학술발표회 논문집
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• pp.140-154
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• 1992

The objective of the research stated here was aimed at providing the information needed to establish the Korean Seismic Design Code Recommendations and Guides for precast concrete (P.C) large panel apartment buildings. This was accomplished by investigation and analysis of the response of P.C large panel structures subjected to shaking table excitation simulating earthquake ground motion. one of the test specimens used was 1/3-scaled 3-story box P.C model provided by Sam-Hwan Camus Corporation. The 4m $\times$4m shaking table was used to simulate the earthquake ground motion. the employed input accelerogram was the one recorded as Taft N21E component and the peak ground acceleration(PGA) was scaled depending on the desired level of seismic severity and the time according to dynamic similitude rule. Based on results obtained from shaking table test of this P.C model, the following conclusions were drawn . (1) As far as test specimen is concerned, the seismic safety factors turns out to be 7~8. (2)P.C model has damping ratio of about8% which is twice larger than in-situ R.C. structure. And (3)this model has global displacement ductility ratio of 2~3 through the energy dissipation by opening and sliding of joints.

• 한국대기환경학회지
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• 제23권1호
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• pp.14-28
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• 2007

This study presented the selection of ozone ($O_3$) potential factors and designed and assessed its potential prediction model using multiple-linear regression equations in Ulsan area during the springtime from April to June, $2000{\sim}2004$. $O_3$ potential factors were selected by analyzing the relationship between meterological parameters and surface $O_3$ concentrations. In addition, cluster analysis (e.g., average linkage and K-means clustering techniques) was performed to identify three major synoptic patterns (e.g., $P1{\sim}P3$) for an $O_3$ potential prediction model. P1 is characterized by a presence of a low-pressure system over northeastern Korea, the Ulsan was influenced by the northwesterly synoptic flow leading to a retarded sea breeze development. P2 is characterized by a weakening high-pressure system over Korea, and P3 is clearly associated with a migratory anticyclone. The stepwise linear regression was performed to develop models for prediction of the highest 1-h $O_3$ occurring in the Ulsan. The results of the models were rather satisfactory, and the high $O_3$ simulation accuracy for $P1{\sim}P3$ synoptic patterns was found to be 79, 85, and 95%, respectively ($2000{\sim}2004$). The $O_3$ potential prediction model for $P1{\sim}P3$ using the predicted meteorological data in 2005 showed good high $O_3$ prediction performance with 78, 75, and 70%, respectively. Therefore the regression models can be a useful tool for forecasting of local $O_3$ concentration.

• 한국환경과학회지
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• 제12권7호
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• pp.689-695
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• 2003

The purpose of this study is to evaluate and to predict of eutrophication in lakes by using Vollenweider-OECD model and total phosphorus concentration and inflow rate which were measured in 1993∼2001. The results of study were as follows. The annual total phosphorus loading from the watershed was calculated to be 55∼195tP/yr at lake Soyang, 221∼466tP/yr at lake Taechong, 123∼278tP/yr at lake Andong, 57∼109tP/yr at lake Seomjin. These are discharged, far the most parts, from population and fishfarm facility. TP loading on the surface area at lake Soyang was 3.01gP/㎡/yr, 2.82gP/㎡/yr, 2.84gP/㎡/yr, 3.03gP/㎡/yr, 2.34gP/㎡/yr, 1.78gP/㎡/yr, 0.91gP/㎡/yr, 0.89gP/㎡/yr, 0.86gP/㎡/yr, lake Taechong was 6.71gP/㎡/yr, 7.25gP/㎡/yr, 7.24gP/㎡/yr, 6.53gP/㎡/yr, 6.50gP/㎡/yr, 7.06gP/㎡/yr, 7.04gP/㎡/yr, 4.05gP/㎡/yr, 3.44gP/㎡/yr and TP loading on the surface area of lake Andong, lake Soemjin were 5.39gP/㎡/yr, 4.47gP/㎡/yr, 4.56gP/㎡/yr, 4.45gP/㎡/yr, 3.33gP/㎡/yr, 2.38gP/㎡/yr, 2.53gP/㎡/yr, 2.46gP/㎡/yr, 2.54gP/㎡/yr, 4.09gP/㎡/yr, 4.10gP/㎡/yr, 3.98gP/㎡/yr, 3.73gP/㎡/yr, 2.80gP/㎡/yr, 3.46gP/㎡/yr, 3.22gP/㎡/yr, 2.19gP/㎡/yr, 2.13gP/㎡/yr respectively. The tropic states of four lakes can be assessed as eutrophy because phosphorus leading exceeds the critical phosphorus loading by Vollenweider-OECD model.

• 시큐리티연구
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• 제37호
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• pp.137-163
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• 2013

이 연구는 미국 공립학교의 사례를 통해 학교 내 안전을 미치는 요인과 학교 내 안전에 효율적인 경비형태를 분석함으로서 국내 학교 내 안전을 높일 적절한 방안을 제시하는데 그 목적이 있다. 이 연구는 학교 내에서 발생하는 범죄를 종속변수로 하는 중범죄모델과 범죄의 유형에는 포함되지 않더라도 학생들의 안전을 위협할 수 있는 비행행위 및 집단행위로 범위를 한정시켜 종속변수로 하는 학교폭력모델로 나뉜다. 첫 번째, 학교 내 안전에 영향을 미치는 요인의 분석결과, 중범죄안전 모델과 학교폭력 안전 모델의 설명력은 각각 10.3%, 12%이며, 중범죄안전 모델을 살펴보면 학생을 대상으로 한 안전교육(t=2.521, p=0.012), 학교활동 부모참여(t=11.733, p=0.000), CPTED활동(t=3.206, p=0.001), 학교 내 경비활동(t=2.983, p=0.003)이 통계적으로 유의미하게 중범죄로 부터의 안전에 긍정적인 영향을 미치는 요인으로 나타났다. 학교폭력안전 모델에서도 유사하게 학교활동의 부모참여(t=10.399, p=0.000), CPTED활동(t=7.238, p=0.000), 학교내 경비활동(t=4.018, p=0.000)이 통계적으로 유의미하게 학교폭력으로 부터의 안전에 영향을 미치는 요인으로 나타났다. 두 번째, 어떠한 유형의 경비활동이 학교 내 안전을 높이는지 분석한 결과, 중범죄안전 모델과 학교폭력안전 모델, 두가지 모델의 설명력은 각각 4.4%, 3.9%이며, 중범죄 안전 모델에서는 학교에서 실행하는 경비활동 중 지역경찰과의 협조(t=2.112, p=0.035), 교칙관리(t=3.309, p=0.001), 경비순찰활동(t=2.548, p=0.011)이 통계적으로 유의미하게 중범죄로 부터의 안전에 영향을 미치는 요인으로 나타났고, 학교폭력안전 모델에서는 경비활동 중 지역경찰과의 협조(t=2.364, p=0.018), 교칙관리(t=4.142, p=0.000)가 통계적으로 유의미하게 중범죄로 부터의 안전에 영향을 미치는 요인으로 나타났다. 이 연구의 결과에 따라 교사에 대한 교육보다 학생에 대한 교육이 학교 내 안전에 긍정적이고, 학교 운영에 부모참여도 교육과 마찬가지로 지속적이고 계속적인 참여가 학교안전을 위해 필요하다. CPTED활동의 경우, 미국의 사례의 결과를 그대로 받아들여 강화하는 방안을 마련하고, 경비활동에 관하여는 가시성을 높이고 지역경찰과의 협조를 원활히 하는 방안이 학교 내 안전에 긍정적 영향 줄 것이다.