• Journal of the Korean Mathematical Society
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• v.40 no.5
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• pp.901-920
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• 2003

The notion of infinitely near singular points, classical in the case of plane curves, has been generalized to higher dimensions in my earlier articles ([5], [6], [7]). There, some basic techniques were developed, notably the three technical theorems which were Differentiation Theorem, Numerical Exponent Theorem and Ambient Reduction Theorem [7]. In this paper, using those results, we will prove the Finite Presentation Theorem, which the auther believes is the first of the most important milestones in the general theory of infinitely near singular points. The presentation is in terms of a finitely generated graded algebra which describes the total aggregate of the trees of infinitely near singular points. The totality is a priori very complex and intricate, including all possible successions of permissible blowing-ups toward the reduction of singularities. The theorem will be proven for singular data on an ambient algebraic shceme, regular and of finite type over any perfect field of any characteristics. Very interesting but not yet apparent connections are expected with many such works as ([1], [8]).

• Architectural research
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• v.18 no.4
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• pp.171-178
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• 2016

Architectural utility in Richard Neutra's early twentieth century modern school design was paramount in progressively shaping salience of academic institutions, in part to move beyond neoclassical traditions in style based design. The intention being to address school and community through modern architectural solutions. Expanding on Neutra's practice, the planning and design of new public schools in Los Angeles, are advocating the integration of institutional and public spaces. This research will document through qualitative analysis of institutional design within transitioning neighborhoods, a utilitarian approach that has become foundational for positive urban change. The focus of this research will reflect upon contemporary schools designed by DalyGenik Architecture, Coop Himmelblau and Michael Maltzen Architecture. Comparing with Neutra's early modernist approach, the selected case studies will address material and spatial applications having redefined functional relationships of interior space, architectural envelope and an interconnected public realm. A dynamic peripheral condition in new school design has emerged with the elimination of decorative adornment, clarifying utilitarian intentions of institutional service to and the rejuvenation of public realms and community spaces.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1215-1218
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• 2003

An analysis of the bonding situation in CaM₂P₂ (M=Fe, Ni) with ThCr₂Si₂ structure is made in terms of DOS and COOP plots. The main contributions to covalent bonding are due to M-P and P-P interactions in both compounds. Particularly, the interlayer P-P bonding by variation in the transition metal is examined in more detail. It turns out that the shorter P-P bonds in CaNi₂P₂ form as a result of the decreasing electron delocalization into ${{\sigma}_p}^*$ of P₂ due to the weaker bonding interaction between the metal d and ${{\sigma}_p}^*$ as the metal d band is falling from Fe to Ni.

• Journal of Biosystems Engineering
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• v.32 no.5
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• pp.279-283
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• 2007

In this study, the potential possibility of oxygenates on di-ether group (DBE, dibutyl ether) was investigated as an additives for an agricultural direct injection diesel engine. It tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenates additives blending fuel which has four kinds of mixed ratio. The smoke emission of blending fuel (diesel fuel 80 vol-% + DBE 20 vol-%) was reduced in comparison with diesel fuel, that is, it was reduced approximately 26% at 2500 rpm, full load. And, power, torque and brake specific energy consumption didn't have large differences. But, NOx emission of blended fuel was increased compared with commercial diesel fuel.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2016.11a
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• pp.418-423
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• 2016

대규모 광역정전은 현대사회에서 발생할 수 있는 가장 심각하고 광범위한 피해를 입힐 수 있는 재난 중에 하나이다. 모든 시스템이 전력으로 구동되며, 전산화되어 있는 현대 사회에서 광역정전이 발생한다면 큰 사회적 혼란이 발생할 것이다. 선행연구에 따르면, 광역정전이 발생 하였을 때, 자체 방재력에도 불구하고 10시간 정도가 지나면 대부분의 국가기반시설이 제 기능을 못하는 것으로 나타났다. 그럼에도 불구하고, 아직까지 우리나라에서는 대규모 광역정전에 대한 제도적 연구가 미흡한 실정이다. 본 연구의 목적은 대규모 광역정전과 관련한 현 제도의 문제점을 파악하고 이를 개선하는 것이다. 이를 위해 본 연구에서는 현행법과 정전매뉴얼 등을 조사하였다. 그 결과 국가기반시설 상호연계성에 따른 COOP의 적용 및 포괄적 위기관리 프레임워크 도입, 시계열적 매뉴얼 제작이 필요하다는 결과가 도출됐다. 이러한 본 연구의 결과는 대규모 광역정전뿐만 아니라 미래재난 전반에 걸친 적용이 가능할 것으로 사료된다.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.04a
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• pp.10-12
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• 1991

The first membrane technology applied in the Japanese industry was a. electro-dialysis(ED) process using ion-exchange meabranes. These membranes were first developed in early 50ties and the Japanese government decided to use this method for concentration of sea water to produce salt, which was then produced by solar evaporation. This development program started from 1960 by the Japan monopoly Coop. (at that time). To apply ED process for sea-water concentrat ion it was necessary to develop ion-exchange membranes having very low electric resistance to avoid energy loss due to Joule heat, and those having selectivity to permeate single valent ions only to avoid scale formation in the ED stacks. These Japanese companies, Asahi Glass, Asahi Chemical and Tokuyama Soda, have succeeded to develop such membranes, and until 1971 all of the seven salt manufacturing companies had adopted ED for production of food salt.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.35-39
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• 2013

The chemical bonding and elastic properties of $Ti_2AC$ (A = Ga, Tl) have been investigated by means of extended H$\ddot{u}$ckel tight-binding band structure calculations. The bulk modulus of $Ti_2AC$ decreases as Ga is replaced with Tl at the A sites. This can be understood by considering the relative strength of Ti-A bonds resulting from the different atomic size of 3A-group elements. The analysis of the projected density of states (PDOS) and the crystal orbital overlap population (COOP) for the respective phases shows that Ti-Ga bonds in $Ti_2GaC$ are stronger than Ti-Tl bonds in $Ti_2TlC$.

• Bulletin of the Korean Chemical Society
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• v.15 no.2
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• pp.139-145
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• 1994

The DOS, COOP and O 1s binding energy are calculated for Ni24(100) model surface with oxygen adsorbed on it. The calculation is made with PC/386 using the program obtained by converting EHMACC(VAX version) into PC version. The calculation shows the dissociative adsorption of oxygen molecule, of which the main cause is attributed to the transfer of the $d{\pi}$ and $d{\delta}$ electrons of Ni to the antibonding $1{\pi}_g$ of oxygen molecule. The O ls shift on the adsorption is calculated using the valence potential method, and the results agree fairly good with the experimental values.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1093-1097
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• 1994

The interaction of oxygen molecule with Ni44(111) model surface to which the molecule approaches is studied by calculating the relevant DOS and COOP with the tight-binding EHT method. It is found that the dissociative adsorption of oxygen takes place as a result of electron transfer from the Ni d${\pi}$ orbital to the antibonding 1${\pi}_g$ orbital of the oxygen molecule. This finding is noteworthy to contrast with the case of Ni(100) surface in which the electron transfer takes place from the Ni d${\delta}$ orbital of the nickel surface.

• Bulletin of the Korean Chemical Society
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• v.16 no.2
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• pp.164-168
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• 1995

The band structure of nickel monoxide having a cation defect rock salt structure is calculated by means of the tight-binding extended Huckel method. The calculation is also made for the net charge, the DOS, the COOP, the electron density of the constituent atoms, and the O 1s binding energy shift when one of the adjacent nickel atoms is defected. It is found that the band gap near the Γ direction on the Brillouin zone is about 0.2 eV, and that all of the properties calculated including the electronic structure of the oxygen atom are more effectively affected by the surface defect than the inside one. The core O 1s binding energy shift is calculated by the use of valence potential method and the results are very satisfactory in comparison with the XPS experimental findings.