• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.212-212
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• 2012

The Coverage dependent attachment of multifunctional groups included in threonine molecules adsorbed to Ge (100)$-2{\times}1$ surface was investigated using core-level photoemission spectroscopy (CLPES) and density functional theory (DFT) calculations. The core-level spectra at a low coverage indicated that the both carboxyl and amine groups participated in the bonding with the Ge (100) surface by "O-H dissociated and N-dative bonded structure". However, at high coverage level, additional adsorption geometry of "O-H dissociation bonded structure" appeared possibly to minimize the steric hindrance between adsorbed molecules. Moreover, the C 1s, N 1s, and O 1s core level spectra confirmed that the carboxyl oxygen is more competitive against the hydroxymethyl oxygen in the adsorption reaction. The adsorption energies calculated using DFT methods suggested that four of six adsorption structures were plausible. These structures were the "O-H dissociated-N dative bonded structure", the "O-H dissociation bonded structure", the "Om-H dissociated-N dative bonded structure", and the "Om-H dissociation bonded structure" (where Om indicates the hydroxymethyl oxygen). These structures are equally likely, according to the adsorption energies alone. Conclusively, we investigate in threonine on Ge (100) surface system that the "O-H dissociated-N dative bonded structure" and the "O-H dissociation bonded structure" are preferred at low coverage and high coverage.

• 한국잠사곤충학회지
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• 제39권1호
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• pp.67-72
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• 1997

As a condition for obtaining the silk I type crystal that has stability and high reproducibility, after dissolving silk fibroin crystalline part (Fcp), the changes of recrystallized crystal structure according to dialytic pH were examined by x-ray diffraction and differential thermal analysis. The Fcp was obtained from the aqueous solution of silk fibroin enzymatic proteolyzed by chymotrypsin. The crystal structure of Fcp showed silk II type. When the Fcp was dissolved by 10M LiBr aqueous solution, the Fcp1 showed the silk II type at pH 9. However, besides the silk II type, the silk I type structure begins to appear at pH 8 and only the silk I type structure was found below pH 6. On the other hand, the Fcp2 that calcium chloride was used in the dissolution found only the silk I type crystal structure below pH8.

• 한국전자파학회논문지
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• 제17권8호
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• pp.746-752
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• 2006

본 논문에서는 주기 구조를 이용한 소형화된 partial H-plane필터를 제안하였다. 주기 구조의 관내 파장은 저속파의 영향으로 인해 그 크기가 줄어든다. 주기 구조를 이용한 partial H-plane 필터는 일반적인 E-plane 필터보다 단면적과 길이가 각각 75%, 30% 축소되었다. 또한 대역 통과 필터의 스퓨리어스 응답 특성이 향상되었다. 주기 구조를 이용한 대역 통과 필터를 설계하기 위해 partial H-plane 도파로의 주기 구조가 해석되었고, 설계식이 유도되었다. 측정된 결과는 시뮬레이션 결과와 잘 일치함을 확인할 수 있었다.

• 한국표면공학회지
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• 제33권1호
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• pp.25-33
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• 2000

The synthesis and characterization of intercalated compound of dodecanesulfornate into hydrated metal, [M($H_2$O)\ulcorner](C\ulcornerH\ulcorner$SO_3$)$_2$.$xH_2$O (M=Co, Cu) was presented. The compounds shows a layered structure which was determined by powder X-ray diffraction. Thermal behavior of the layered structure was investigated using thermal analysis, and FT-IR spectroscopy by varying the temperature. The increase in layer spacing of the products by increasing the temperature is also checked by X-ray diffraction. We can suggest three kinds of layered structure by varying the temperature, which is accompanied by changing the intercalated dodecanesulfonate from the monolayer to the bilayer structure or changing the tilt angle.

• Bulletin of the Korean Chemical Society
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• 제22권5호
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• pp.507-513
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• 2001

Histones, nuclear proteins that interact with DNA to form nucleosomes, are essential for both the regulation of transcription and the packaging of DNA within chromosomes. The N-terminal domain of histone H4 which contains four acetylation sites at lysines, may play a separate role in chromatin structure from the remainder of the H4 chain. NMR data suggest that H4NTP peptide does have relating disordered structure at physiological pH, however, it has a defined structure at lower pH conditions. The solution structure calculated from NMR data shows a well structured region comprising residues of Val21-Asp24. In addition, our results suggest that the H4NTP prefers an extended backbone conformation at acetylation sites, however, it (especially Lys 12 ) became more defined structures after acetylation for its optimum function.

• 소음진동
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• 제7권5호
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• pp.803-810
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• 1997

This paper is concerned with the vibration control of multi-layer structure for ultra-tall buildings and main tower of large bridge etc. We have modeled the multi-layer structure with the distributed mass system as the lumped mass system of two-degree-of-freedom structure and made experimental equipment. The $H_\infty$control theory was applied to the design of the control system. The designed control system was simulated by computer. As a result, the designed $H_\infty$controller showed the good vibration control performance to impulse response and frequency response.

• 동력기계공학회지
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• 제7권1호
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• pp.60-67
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• 2003

This paper introduces basic study how to restrain the vibration of a four story shear structure. We have modeled a four story shear structure mathematically and have identified each parameters by experiment. We have gotten a reduced nominal model through modal analyzing method and the $H_{\infty}$ control theory is used in the control system design to get the robust controller. It's shown that the desirable performances is confirmed through the mathematical simulation. And a designed controller applying the $H_{\infty}$ control theory shows the good performance for the impulse disturbance through the simulation results. That is, the robustness of this control system is confirmed for the ability of disturbance rejection and modeling error.

• 한국해양공학회지
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• 제10권4호
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• pp.149-159
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• 1996

Multipurpose development of the coast and ocean can be considered as multifunction construction combining the functions of coastal protection, waterfront amenity and creation or rehabilitation of habitats. Multfunction development of coastal and ocean spaces can be accomplished by applying the ecosystem control structure of artificial habitats which will cultivate fishing ground with ecological harmony to the coastal protection system. To evaluate the applicability of ecosystem control structures as as fundamental coastal protection structure, wave control function of the structure is studied by numerical and physical analyses. Dimensional analysis and hydraulic experiment point out the importance of width and crest depth of ecosystem control structure, construction water depth and wave steepness. Wave control efficiency is estimated by the attenuation coefficient $(K_H)$ according to wave steepness $(H_0/L_0)$, relative constructed water depth $(h_i/H_0)$, relative berm width $(B/L_0)$ and relative crest depth $(h_B/H_0)$ of eosystem control structure. Empirical fomulas are suggested based on the results of model test by applying the multiple model based on this experimental results and numerical wave shoaling-dissipation-breaking model appears to be valid for the analysis of wave transformation around ecosystem control structure in the coastal waters.

• Earthquakes and Structures
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• 제23권2호
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• pp.169-181
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• 2022

To research the dynamic response of the high-rise structure under the rocking ground motion, which we believed that the effect cannot be ignored, especially accompanied by vertical ground motion. Theoretical analysis and shaking table seismic simulation tests were used to study the response of a high-rise structure to excitation of a H-V-R ground motion that included horizontal, vertical, and rocking components. The use of a wavelet analysis filtering technique to extract the rocking component from data for the primary horizontal component in the first part, based on the principle of horizontal pendulum seismogram and the use of a wavelet analysis filtering technique. The dynamic equation of motion for a high-rise structure under H-V-R ground motion was developed in the second part, with extra P-△ effect due to ground rocking displacement was included in the external load excitation terms of the equation of motion, and the influence of the vertical component on the high-rise structure P-△ effect was also included. Shaking table tests were performed for H-V-R ground motion using a scale model of a high-rise TV tower structure in the third part, while the results of the shaking table tests and theoretical calculation were compared in the last part, and the following conclusions were made. The results of the shaking table test were consistent with the theoretical calculation results, which verified the accuracy of the theoretical analysis. The rocking component of ground motion significantly increased the displacement of the structure and caused an asymmetric displacement of the structure. Thus, the seismic design of an engineering structure should consider the additional P-△ effect due to the rocking component. Moreover, introducing the vertical component caused the geometric stiffness of the structure to change with time, and the influence of the rocking component on the structure was amplified due to this effect.

• 통합자연과학논문집
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• 제8권4호
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• pp.250-257
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• 2015

The crystal structure of the potential active 3-(4-ethylphenyl)-3H-chromeno[4,3-c]isoxazole-3a(4H)-carbonitrile ($C_{19}H_{16}N_2O_2$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the monoclinic space group $P2_1/c$ with unit cell dimension a=6.6869 (8) ${\AA}$, b=15.8326 (19) ${\AA}$ and c= 15.237 (2) ${\AA}$ [${\alpha}=90^{\circ}$, ${\beta}=100.663^{\circ}$ and ${\gamma}=90^{\circ}$]. In the structure chromene, isoxazole and carboxylate are almost coplanar each other. All geometrical parameters revelled that chromene ring of pyran ring adopt sofa conformation. The crystal packing is stabilized by intermolecular C-H...N and C-H...O hydrogen bond interaction.