• 대한토목학회논문집
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• 제12권4호
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• pp.1-10
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• 1992

프리스트레스트 콘크리트 교량을 압출공법으로 가설하는 과정에서는 구조계가 계속하여 변하므로 교량의 주형에는 사용하중 상태에서와는 상이한 교번 단면력이 발생하게 된다. 이러한 단면력의 크기는 경간 길이, 추진코의 길이 및 강성등에 영향을 받게 된다. 본 논문에서는 많은 예제를 해석하여 이러한 요소들이 주형에 발생하는 최대 단면력에 미치는 영향을 연구하였다. 주프로그램의 복잡한 입력작업을 쉽게 처리할 수 있는 선처리 프로그램과 더불어 주형압출시 변화되는 구조계의 다단계 해석을 수행하여 최종적인 결과를 종합 출력할 수 있는 전산프로그램을 개발하였다. 압출공법으로 시공되는 박스거더교를 대상으로 하여 여러 가지 경간길이에 대한 구조해석을 수행한 결과로부터 경간 길이에 따른 최적 추진코길이와 강성비의 상호 관계를 제안하였다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2002년도 학술대회지
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• pp.238-252
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• 2002

In order to screen out indicators for the discrimination of ginseng habitat, some physical and chemical characteristics of Korean red ginsengs (94 kinds) and Chinese red ginsengs (50 kinds) were analyzed by using a rheometer, an electronic nose system, a combined technique of solid phase micro-extraction (SPME) and gas chromatograph equipped with an electron capture detector (GC/ECD), an X-ray fluorescence spectrometer (XRF), an inductively coupled plasma mass spectrometer (ICP/MS), a near infrared spectrometer (NIRs) and high performance liquid chromatography equipped with evaporative light scattering detector (HPLC/ELSD). The results are summarized as follows: (i) The rhizome strengths of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. (ii) The electronic nose patterns of Korean red ginsengs were significantly different from those of Chinese red ginsengs. (iii) Some unidentified peaks were detected not in the headspace of Korean red ginsengs but in the headspace of Chinese red ginsengs when the headspace volatiles prepared by the SPME technique were analyzed by GC/ECD. (iv) Either the content ratios of K to Ca or Mn to Fe were significantly different between Korean red ginsengs and Chinese red ginsengs. (v) The reflectance ratios of NIRs wavenumbers such as $904\;cm^{-1}\;to\;1088\;cm^{-1}$ for Korean red ginsengs were significantly different from those for Chinese red ginsengs. (vi) The content ratios of ginsenoside-Rg to ginsenoside-Re of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. These results indicate that the rhizome strength, the electronic nose pattern, the occurrence of ECD-sensitive headspace volatile components, the content ratios of K to Ca and Mn to Fe, the NIRs pattern and the content ratio of ginsenoside-Rg to -Re may be indicators for the discrimination of ginseng habitat.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.187-194
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• 2004

The structural behavior of superstructure by ILM is strongly dependent on the process of launching nose according to the construction process. The ratios of length, weight, and flexural stiffness of launching nose to those of superstructure are taken as the analysis parameters in this study. The interaction behaviors are analyzed according to the variation of parameters. Design formulas to pursue the optimum values for length, weight, and stiffness of launching nose are suggested through the parametric study. As a result, the minimum stiffness ratio is analyzed as I₂/I=0.045 and I₁/I=0.02 for the optimum track of the sectional force while the elastics modulus ratio is 6.8359. Additionally, the design results of real projects are analyzed by the developed formulas to verify that they are designed well in structurally optimal point of view.

• 대한치과교정학회지
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• 제22권1호
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• pp.179-203
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• 1992

This study was designed to analyze nasal respiratory patency and its correlation with skeletal components in growing children with anterior crossbite. The subjects consisted of 40 control patients, 24 nose breathers with anterior crossbite and 18 mouth breathers with anterior crossbite. The mean age was 11.4 years in the control group, 10.1 years in nose breathing group and 9.5 years in mouth breathing group. The results were as follows, 1. In anterior cross bite group, and nasal respiratory airflow rates (N.R.A.R.) was significantly lower than that of control group regardless of nasal decongestants application. 2. The N.R.A.R. of mouth breathers with anterior crossbite in male group was significantly lower than that of mouth breathers, but increased to the level of control group after nasal decongestants application. But in female group, the N.R.A.R. was significantly lower in mouth breathing group at both conditions. 3. Mouth breathing group showed smaller anterior vertical nasal cavity height (ANS-ANS'), lower upper anterior facial height ratios (N-sp'/N-Me) and higher maxillary occlusal plane ratios (OL-ML/ML-NL) than those of nose breathing group with anterior crossibte. 4. Items showing nasal height (ANS-ANS', PNS-PNS'), anterior upper facial height (N-sp') was were strongly correlated with N.R.A.R. at 150 pascal in inspiration. But item showing maxillary occlusal plane ratios (OL-ML/ML-NS) was negatively correlated with N.R.A.R. at 150 pascal in inspiration. 5. There were forward tongue position in mouth breathing group, but it was not significantly correlated with N.R.A.R. at 150 pascal in inspiration.

• 한국식품과학회지
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• 제42권6호
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• pp.676-681
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• 2010

멜라민을 첨가하는 제품들에 대한 기존의 분석법의 한계를 극복하고자 전자코를 이용하여 멜라민 첨가 진위 여부와 첨가 함량의 차이를 분석하였다. 그 결과 멜라민을 분유와 커피 크림에 농도별로 첨가하였을 때 차이가 뚜렷이 구분되었으며 이를 통해 얻은 멜라민 농도와 DF1간의 상관관계식(분유: DF1= -0.006x(멜라민 농도)+0.327, 커피 크림: DF1= -0.006x+0.316)을 바탕으로 멜라민 함량을 적은 오차 범위 내에서 예측 가능하였다. 또한 멜라민을 urea로부터 합성하는 과정에서 생성되는 부산물인 cyanuric acid는 멜라민과 유사하여 기존의 분석방법으로는 쉽게 구분되지 않지만 전자코를 통하여 확연히 구분되었다. 멜라민을 분유나 커피 크림에 첨가하였을 경우에는 농도별로 차이를 보였으며 urea 혹은 cyanuric acid 첨가 유무에 따라서는 미세한 차이는 보였지만 첨가양에 따른 일정한 경향을 나타나지 않은 것으로 보아 유사물질의 영향을 거의 받지 않으면서 멜라민 자체만의 분석이 가능한 것으로 보인다. 이러한 연구를 통하여 향후 미지의 멜라민 함량이 첨가된 1차 가공품에 대한 함유량을 분석하는 것이 가능하며 제품의 품질관리시 활용할 수 있는 대안을 제시할 수 있을 것이다.

• 한국식품과학회지
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• 제43권1호
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• pp.105-109
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• 2011

본 연구는 유채유에 타기름이 혼합되었을 때 그 혼합 비율에 따른 차이를 전자코로 분석하였다. 대두유와 옥수수유를 0, 3, 6, 9, 12, 15, 20%를 유채유에 각각 혼입하여 전자코로 분석한 결과 DF1의 영향을 주로 받아 혼합 비율이 증가함에 따라 DF1이 음의방향으로 일정한 경향을 보이며 이동하여 나타났다. 이를 혼합비율에 따른 DF1값을 막대그래프로 나타낸 결과 혼합비율이 증가함에 따라 DF1값이 감소하여 뚜렷한 차이를 보였다. 유채유에 대두유를 혼합할 경우 DF1= $-0.170{\times}conc.$(대두유 혼합비율)+0.431 ($r^2=0.989$)과 같은 상관관계식을 얻어 유채유에 타 기름이 혼합될 경우 그 함량의 예측이 가능하였다. 이러한 결과를 통해 전자코를 이용하여 유채유의 위조판별이 가능함을 확인하였으며 다른유지를 비롯한 다양한 식품에 적용 가능할 것이다.

• 한국축산식품학회지
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• 제31권2호
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• pp.273-279
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• 2011

전자코를 이용하여 아카시아 꿀, 잡화 꿀, 밤 꿀, 유채꿀, 사양 꿀, 목청 꿀, 기타 꿀을 대상으로 밀원에 따른 차이를 구분하였다. 그 결과 꿀 종류에 따라 뚜렷이 구분 가능하였으며 각기 다른 꿀을 혼합하였을 때 혼합 비율에 따라서도 구분 가능하였다. 0, 5, 10, 15, 20, 25, 30%의 사양 꿀을 목청 꿀에 혼합하였을 때 혼합비율이 증가함에 따라 41, 42, 43, 45, 46, 47, 48, 54, 56, 58, 60 amu의 감응도 값이 크게 나타났으며 판별함수분석한 결과 사양 꿀의 혼합비율이 증가함에 따라 DF1값이 양의 방향에서 음의 방향으로 일정한 경향을 보이며 뚜렷이 구분되었다(DF1: $r^2$=0.9962, F=490.6 DF2: $r^2$=0.9128, F=19.44). 이를 통하여 DF1값과 목청 꿀에 사양 꿀의 혼합 농도에 대해 DF1=-0.106$^*$(사양 꿀의 농도)+0.426($r^2$=0.96)와 같은 높은 상관관계식을 얻었다. 아카시아 꿀의 경우에도 목청 꿀과 유사하게 사양 꿀의 혼합비율이 증가함에 따라 41, 43, 45, 46, 47, 56, 57, 58, 59, 60, 61, 70 amu의 감응도 값이 크게 나타났으며 DF1과 사양 꿀 혼합 비율간에 높은 상관관계를 보이며 일정한 경향을 나타냈고(DF1: $r^2$=0.9957, F=396.64 DF2: $r^2$=0.9447, F=29.3) DF1=-0.112$^*$(사양 꿀의 농도)+0.434($r^2$=0.968)의 상관관계식을 갖는다.

• 대한두개안면성형외과학회지
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• 제22권2호
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• pp.85-92
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• 2021

Background: Patients with secondary deformities associated with unilateral cleft lip and nose might also suffer from nostril stenosis due to a lack of tissue volume in the nostril on the cleft side. Here, we used full-thickness skin grafts (FTSGs) to reduce nostril stenosis and various methods for skin volume augmentation. We compared the changes in the symmetry of both nostrils before and after surgery. Methods: From February 2016 to January 2020, 34 patients underwent secondary cheiloplasty and open rhinoplasty for secondary deformities of the unilateral cleft lip and nose with nostril stenosis. FTSG was used on the nostril floor, nasal columella, and alar inner lining. The measured nasal profile included the nostril surface, nostril circumference, width of the nostril floor, and distance from the alar-facial groove to the nasal tip. The "overlap area," which was defined as the largest overlapping area when the image of the cleft nostril was flipped to the left and right and overlaid on the image of the normal side nostril, was also calculated. The degree of symmetry was evaluated by dividing the value of the cleft side by that of the normal side of each measured profile and expressed as "ratios." Results: The results of all profile ratios, except for the nostril floor width, became significantly close to 1, which represents full symmetry. The overlap area ratio improved from 62.7% to 77.3%, meaning that the length and width of the nostril as well as the overall shape became similar (p< 0.05). Conclusion: When performing cleft rhinoplasty with nostril stenosis, FTSG is useful to achieve symmetry in the nostril size and shape. Skin grafting is simpler to perform than the other types of local flap, and the results are generally satisfactory.

• 대한건축학회논문집:구조계
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• 제35권2호
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• pp.13-20
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• 2019

This study was conducted in order to validate the nose shape factors of projectile in existing impact formulas for high-strength concrete in the event of collision with high-speed projectiles. In order to conduct the high-speed impact experiment, specified concrete strengths of 35, 100, and 120 MPa were prepared and tested in collision with both conical and hemispherical projectiles. The results showed that the measured penetration depth did not decrease linearly as concrete strength increased. Comparing the ratio penetration depth to the kinetic energy of the conical and hemispherical projectiles, the difference in the ratios for high strength concrete was observed to decline as concrete strength increased. However, in the modified NDRC and the Hughes formulas, the difference in the predicted penetration depth of the conical and hemispherical projectiles was constant despite increasing concrete strength. The modified NDRC and Hughes formulas should be improved upon so as to be applied to high strength concrete.

• 한국정밀공학회지
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• 제12권3호
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• pp.119-129
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• 1995

In this paper, the inclined endmilling process with a 3-axis machining center using inclined jigs is introduced for the purpose of reducing overall Dies/Molds machining time and improving the machining accuracies. In order to analyze the cutting mechanism of a given endmill more accurately, the unification of the cutting mechanism model of 3-different- kind endmills is carried out by using a nose radius as a parameter. By adding radial runouts as a parameter which influences on surface roughness, the superposition method which defines the effective cusp height superposing the cutter mark height and the conventional cusp height is advanced. And 3-D suface topography predicted in this paper looks like the surface normally observed in practice. Through machining experiments, the adequacy of the superposition method was confirmed.