항공우주 기술분야 출원동향

조성길,Jo, Seong-Gil 한국특허정보원 2004 Patent 21 Vol.56 No.-

Asymptotical Shock Wave Model for Acceleration Flow

조성길 한국ITS학회 2013 한국ITS학회논문지 Vol.12 No.3

충격파모형은 교통류에서 운동학적 파동이 전파되는 속도이며, Lighthill과 Whitham(L-W)에 의해 처음 제시되 이래 지금까지 많은 교통류 문제에 적용되어지고 있다. 최근의 한 논문은 실재상황에서 발생되지 않는 충격파가 L-W모형에서 예측되는 모순을 지적하였고, 이러한 모순이 발생되는 원인과 이를 해소하는 새로운 점진적충격파모형을 제시한 바 있다. 그러나 이 모형은 교통류 흐름 중 감속하는 교통류에 대해 한정하여 유도 되었으며 반대상황 즉 가속하는 교통류에 대한 모형은 아직 제시되지 못하고 있다. 본 연구에서는 가속 교통류에 대한 점진적 충격파모형을 유도하고 이를 검증하고자 한다. 이를 위해 가속상태의 교통류에서 추종차량의 가속에 따른 차량간의 간격이 Greenshield의 모형을 충실히 따르도록 한정하고 이를 바탕으로 충격파모형을 유도하였다. 그 결과 본 연구에서 제시된 모형은 L-W모형의 모순이 해소됨을 확인하였고, 사례교통량을 적용해 기존모형들과의 결과 차이를 정량적으로 확인하였다. 한편 모형간의 차이가 분명하고도 구조적인 것을 확인하였고 이에 대한 추가적인 향후 연구의 필요성을 제시하였다. Shock wave model describes the propagation speed of kinematic waves in traffic flow. It was first presented by Lighthill and Whitham and has been deployed to solve many traffic problems. A recent paper pointed out that there are some traffic situations in which shock waves are not observable in the field, whereas the model predicts the existence of waves. The paper attempted to identify how such a counterintuitive conclusion results from the L-W model, and resolved the problem by deriving a new asymptotical shock wave model. Although the asymptotical model successfully eliminated the paradox of the L-W model, the validation of the new model is confined within the realm of the deceleration flow situation since the model was derived under such constraint. The purpose of this paper is to derive the remaining counter asymptotical shock wave model for acceleration traffic flow. For this, the vehicle trajectories in a time-space diagram modified to accommodate the continuously increased speed at every instant in such a way that the relationship between the spacing from the preceding vehicle and the speed of the following vehicle strictly follows Greenshield’s model. To verify the validity of the suggested model, it was initially implemented to a constant flow where no shock wave exists, and the results showed that there exists no imaginary shock wave in a homogeneous flow. Numerical applications of the new model showed that the shock wave speeds of the asymptotical model for the acceleration flow tend to lean far toward the forward direction consistently. This means that the asymptotical models performs in a systematically different way for acceleration and for declaration flows. Since the output difference among the models is so distinct and systematic, further study on identifying which model is more applicable to an empirical site is recommended.

방사선 조사된 참깨에서 hydrocarbon류 검지를 위한 초임계 유체 추출 공정의 이용

조성길,서상철,이보경,홍주헌,최용희 한국산업식품공학회 2003 산업 식품공학 Vol.7 No.4

초임계 유체 추출 공정을 이용하여 참깨에서 hydrocarbon류를 검출하여 참깨의 방사선 조사 여부 검지 전처리 기술에 활용하고자 하였다. 참깨를 2 kGy의 감마선을 조사하여 hexane으로 지방을 추출한 용매 추출과 초임계 유체 추출을 이용하여 추출한 지방을 Florisil coulumn으로 분리한 후 hydrocarbon 류를 GC-MS로 분석하였다. 용매 추출에서와 같이 초임계 유체 추출 공정을 이용하여 검출된 hydrocarbon 류은 동일하게 검지되었으며 그 marker 로써 활용 가능한 hydrocarbon 류인 13:3, 17:2, 16:2, 17:1은 비조사 참깨에서는 검출되지 않아TEk. 보조 용매르 사용한 초임계 추출 공정에서 각 보조용매에서 추출된 지방량은 용매 추출보다 많았으며 보조용매를 사용하여 검출된 hydrocarbon 류의 검출량은 methanol을 제외하고 전반적으로 많이 검출되었다. 특히 acetone의 경우 marker로 사용가능한 hydrocarbon류는 용매 추출에서보다 3~4배 정도, CO₂만을 사용함 초임계 유체 추출 공정에서 보다 거의 2배의 검출 특성을 보여주었다. 이러한 결과는 초임계 유체 추출 공정이 방사선 조사 여부 검지 기술에 있어서 기존의 용매 추출에 비해 지방 추출시 용매 소모량의 감소, hydrocarbon 류의 검출량 증가 등의 이유로 hydrocarbon 류의 검지 기술에 있어 전처리 기술로 활용 가능하리라 사료된다. Radiation-induced hydrocarbons from the irradiated sesame were investigated in this study to compare the chemical properties of irradiated and non-irradiated foodstuff. The detective volatile hydrocarbons for the irradiated sesame were (C14:0), 1-tetradence (C14:1), n-pentadecane (C15:0), n-hexadecane (C16:0), 1-hexadecane (C16:1), n-heptadecane (C17:0), 8-heptadecene (C17:0), 1,7-hexadecadiene (C16:2) 1,7,10-hexadecadiene (C16:3) 6,9-heptadecadiene (C17:2). The characteristic of extracts was also investigated at the change of pressure and temperature. And then it was found that the increase of the pressure and the decrease of the temperature in supercritical fluid extraction have made possible much more rapid extraction of volatile hydrocarbons. The amounts of volatile hydrocabons for irradiated and non-irradiated foodstuff were definitely differentiate. It could be concluded that the supercritical fluid extraction was possible for detective extraction method irradiated foods.

A Study on Synthetic OD Estimation Model based on Partial Traffic Volumes and User-Equilibrium Information

조성길,Cho, Seong-Kil Intelligent Transportation Systems 2008 한국ITS학회논문지 Vol.7 No.5

This research addresses the problem of estimating Origin-Destination (O-D) trip matrices from link volume counts, a set of unobserved link volumes and information of user equilibrium flows in transportation networks. A heuristic algorithm for estimating unobserved link flows is derived, which provides volume estimates that are approximately consistent with both observed flows and an assumption of user equilibrium conditions. These estimated link volumes improve the constraints associated with the synthetic OD estimation model, providing improved solution search procedure. Model performance is tracked in terms of the root mean square errors (RMSE) in predicted travel demands, and where appropriate, predicted linked volumes. These results indicate that the new model substantially outperforms existing approaches to estimating user-equilibrium based synthetic O-D matrices. 본 논문은 교통망에서 관측 링크 교통량, 미관측 링크의 이용자평형 정보를 이용하여 O-D행렬을 수학적으로 생성하는 모형을 제시하고 있다. 교통량이 관측되지 않은 링크로부터 이용자 평형 상태에서 추출 가능한 정보를 바탕으로 일련의 논리적 연산을 거쳐 실제교통량에 근접하는 서브알고리듬을 유추하여 O-D행렬 추정의 정확도와 연산의 일관성을 제고하였다. 이를 위해 이용자평형상태에서 새로운 정리(Theorem)와 보조정리(Lemma)를 유도하여 적용하였다. 모형의 시험은 3개의 초기 O-D 행렬과 3개의 미관측 링크 교통량 시나리오를 각각의 모형에 적용하여 그 결과를 비교하였다. 적용 결과 본 논문에서 제시된 모형은 기존의 이용자균형 접근방식의 모형emf에 비해 추정된 O-D값의 실제 값과의 차이(O-D Trip RMSE)가 현저히 감소되는 것을 확인하였다.

부가가치세법상 과세특례제도와 간이과세제도의 문제점 및 개선방향

조성길 又石大學校 1996 論文集 Vol.18 No.-

개정된 자산재평가법이 지방세에 미치는 효과

조성길 又石大學校 1998 論文集 Vol.20 No.-

The asset revaluation system has been applied in practical fields since 1958 in Korea. We have two points of view on the asset revaluation system; first this system must be continued to exist for purpose of improving financial structure and competitive power, second this system has to be abolished on account for weekening creditability and comparability of accounting information, and in due to harm fairness of tax burden. In Korea, the asset revaluation law was reformed of April 10, 1998. Therefore this article is purposed to study the contents of asset revaluation reformed-law and to understand effect of asset revaluation reformed-law on local taxes. The results of this article are as follows; the asset revaluation system must be abolished after taking alternative, and this system affects on registration tax and acquisition tax in local taxes.

소월과 목월시의 자연관 비교 고찰 - 소월시와 청록집 산도화를 중심으로 -

조성길 한성대학교 한성어문학회 1983 漢城語文學 Vol.2 No.-

초임계 추출 공정을 이용한 유자 씨에 함유된 Nomilin 추출조건의 최적화

조성길,홍주헌,서상철,이보경,최용희 한국산업식품공학회 2005 산업 식품공학 Vol.9 No.1

Supercritical fluid extraction (SFE) has been used to extract the nomilin from citron seeds. The extraction pressure was increased 100 to 300 bar at the interval of 100 bar, at the temperature 40, 60, 80oC and the extracted time 30, 90, 150 min at CO2 flow rate 2 mL/min. Overall experiments were planned by central composition design and the results were analyzed by response surface methodology to find out the effects of three independent variables such as pressure (X1), temperature (X2) and time (X3) on the yield of nomilin extract (Y). Extraction yields of nomilin were affected by pressure, time and temperature in the decreased order, and the Taylor second order equation was obtained as Y=-650.683283 +11.337258X1-9.569495X2+3.874388X3-0.023381X1 2+0.039897X2 2-0.021832X3 2+0.006699X2X1+0.007193X3X1+ 0.004717X3X2. The optimum condition for the extraction process was obtained as the extraction pressure of 255 bar, and the time of 117 min at the fixed temperature of 46oC.

삼중식 부기시스템에 관한 연구 : Yuji Ijiri의 삼중식부기시스템을 중심으로 with the emphasis upon Ijiri's triple-entry bookkeeping system

조성길 又石大學校 經營硏究所 1990 經營硏究 Vol.1 No.1

The perfectness of double-entry bookkeeping system has been praised by many notable authors in history. And ever since it was developed, the basis of framework of double-entry bookkeeping system has remained unchanged for more than five centuries. But it is possible that the dichotomy of double-entry bookkeeping system is extended to trichotomy of triple-entry bookkeeping system by means of interpreting existing two dimensions of double-entry bookkeeping system as wealth=capital instead of conventional interpretation, that is assets=equities. Therefore, the purpose of this study is to present the triple-entry bookkeeping system in order to disprove the perfectness hypothesis of double-entry bookkeeping system. The results of this study are as follows; 1) Temporal triple-entry bookkeeping system can be presented because of being able to extend the dichotomy of present(wealth)=past(capital) to the trichotomy of future(budget)=present(wealth)=past(capital). 2) Differential triple-entry bookkeeping system can be presented because of being able to consider capital as the "derivative" of the wealth and force as the "derivative" of the capital. Finally consideration of accounting in the third dimension are as follows; 1) extension of triple-entry bookkeeping system to quadruple-entry bookkeeping system or multi-entry bookkeeping system, 2) possibility of extension of causal entry bookkeeping to triple-entry bookkeeping, 3) implementation of triple-entry system in real world.

고분해능 전자현미경에 의한 Al-Li-Cu-Mg-Zr 합금의 석출거동

조성길,이신호,황돈하,주승원,이응조 대한금속재료학회(대한금속학회) 1994 대한금속·재료학회지 Vol.32 No.9

The precipitation behavior in Al-2.28wt%Li-1.11wt%Cu-0.57wt%Mg-0.18wt%Zr alloy has been studied by using a high resolution electron microscope. In the alloy quenched from 530℃, the Ll₂-type microdomains with a few unit cells and regions having lattice modulation parallel to {100} planes are observed in an atomic resolution image. After an aging at 190℃ for 10min, the discrete δ´-ordered precipitates with 4 to 8㎚ in size are recognized in fcc disordered matrix. In the θ´/δ´complex precipitates, interface boundary on both faces of θ´ plate is atomically flat and coherent with surrounding δ´ phase and an antiphase relation is formed between the δ´ phases on both faces of θ´ plate. Nucleation sites of S´ phase are observed at not only δ´/matrix interface and subgrain boundary, but Cu and Mg clusters. In the β´/δ´ complex precipitates, β´ and δ´ phases are slightly misoriented with respect to each other and a lattice misfit of about 10㎚ width is partially observed in the interface boundary.