• Journal of Electrical Engineering and Technology
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• 제11권6호
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• pp.1556-1570
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• 2016

In the process of virtual inertia control (VIC), the frequency regulation capability of the directly-driven wind turbine with permanent-magnet synchronous generator (D-PMSG) on wind farm is related to its rotor kinetic energy and capacity margin. This paper proposes the method for assessing the D-PMSG frequency regulation capability and defining its coefficient according to the operating state of wind power generators. In addition, the calculating method of parameters in VIC is also discussed according to the principles of primary frequency regulation and inertia response of synchronous generators. Then, by introducing the capability coefficient into the proportion-differential virtual inertia control (PD-VIC) for power coordination, a coordinated virtual inertia control (C-VIC) strategy is developed, with the consideration of the difference in frequency regulation capability between wind power generators. The proposed control method can not only give full play to the frequency regulation capability of wind power generators, decrease the movements of the pitch angle control system but also bring some self-coordination capability to different wind power generators thus to avoid a secondary drop in system frequency. The simulations and experiments prove the proposed method to be effective and practicable.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1359-1365
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• 2005

A series of new chiral [iminophosphoranyl]ferrocenes, {${\eta}^5-C_5H_4-(PPh_2=N-2,6-R_2-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-PPh^2-2-CH(Me)NMe_2$} (1: R = Me, $^iPr$), {${\eta}^5{-C_5H_4-(PPh_2=N-2,6-R_2}^1-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-(PPh_2=N-2,6-R_2-C_6H_3)-2-CH(Me)R_2$} (2: $R^1\;=\;Me,\;^iPr;\;R^2\;=\;NMe_2$, OMe), and $({\eta}^5-C_5H_5)Fe${${\eta}^5-C_5H_4-1-PR_2-2-CH(Me)N=PPh_3$} (3:R = Ph, $C_6H_{11}$) have been prepared from the reaction of [1,1'-diphenylphosphino-2-(N,N-dimethylamino) ethyl]ferrocene with arylazides (1 & 2) and the reaction of phosphine dichlorides ($R_3PCl_{2}$) with [1,1'-diphenylphosphino-2-aminoethyl]ferrocene (3), respectively. They form palladium complexes of the type $[Pd(C_3H_5)(L)]BF_4$ (4-6: L = 1-3), where the ligand (L) adopts an ${\eta}^2-N,N\;(2)\;or\;{\eta}^2$-P,N (3) as expected. In the case of 1, a potential terdentate, an ${\eta}^2$-P,N mode is realized with the exclusion of the –=NAr group from the coordination sphere. Complexes 4-6 were employed as catalysts for allylic alkylation of 1,3-diphenylallyl acetate leading to an almost stoichiometric product yield with modest enantiomeric excess (up to 74% ee). Rh(I)-complexes incorporating 1-3 were also prepared in situ for allylic alkylation of cinnamyl acetate as a probe for both regio- and enantioselectivities of the reaction. The reaction exhibited high regiocontrol in favor of a linear achiral isomer regardless of the ligand employed.

• 대한화학회지
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• 제56권6호
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• pp.679-691
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• 2012

New series of metal complexes of Co(II), Ni(II), Cu(II), Zn(II), Pd(II) and Pt(II) with 4-(p-chlorophenyl)-1-(pyridin-2-yl)thiosemicarbazide (HCPTS) have been synthesized and characterized by elemental analyses, magnetic moment, spectra (IR, UV-Vis, $^1H$ NMR, mass and ESR) and thermal studies. The IR data suggest different coordination modes for HCPTS which behaves as a monobasic bidentate with all metal ions except Cu(II) and Zn(II) which acts as a monobasic tridentate. Based on the electronic and magnetic studies, Co(II), Cu(II), Pd(II) and Pt(II) complexes have square - planner, Ni(II) has mixed stereochemistry (tetrahedral + square planar), while Zn(II) is tetrahedral. Molar conductance in DMF solution indicates the non-ionic nature of the complexes. The ESR spectra of solid copper(II) complex show $g_{\parallel}$ (2.2221) > $g_{\perp}$ (2.0899) > 2.0023 indicating square-planar structure and the presence of the unpaired electron in the $d_x2_{-y}2$ orbital with significant covalent bond character. The thermal stability and degradation kinetics of the ligand and its metal complexes were studied by TGA and DTA and the kinetic parameters were calculated using Coats-Redfern and Horowitz-Metzger methods. The complexes have more antibacterial activity against some bacteria than the free ligand. However, the ligand has high anticancer activities against HCT116 (human colon carcinoma cell line) and HEPG2 (human liver hepatocellular carcinoma cell line) compared with its complexes.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4131-4136
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• 2012

Several palladium complexes containing ${\beta}$-ketoiminate and ${\beta}$-diketiminate ligands successfully produced poly(DCPD) possibly via vinyl addition. It was found that catalysts with ${\beta}$-diketiminate ligands containing bulkier aryl substituents showed the highest activity in the presence of MAO as a cocatalyst. Purity of DCPD is quite essential for the higher activity and small amount of organic solvent such as $CH_2Cl_2$ and toluene is required to reduce the viscosity of the reactant mixture for the higher activity. $^1H$ NMR spectra of produced polymers with N,N-dimethylanilinium tetra(pentafluorophenyl)borate (N,N-DAPFAr"$_4$) show that 5,6-double bond of DCPD is removed with 2,3-double bond remaining. Produced poly(DCPD) with MAO cocatalyst is quite rigid and insoluble in common organic solvents but rather brittle.

• 대한건축학회논문집:계획계
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• 제34권4호
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• pp.19-25
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• 2018

At present, there are many companies that can produce modular housing. However, if the housing projects are conducted without design standards and principles, each company will supply housing according to its own design standards, resulting in a loss of opportunity to promote standardization at a national level. Korea's modular construction technology is still in its infancy, and there is a lack of MC design applications due to the limited construction market. In recent years, however, related R&D has been carried out by the Ministry of Land, Infrastructure and Transport in order to activate modular construction. As a result, test-beds for public rental housing are currently being built, and the public rental housing applied with the modular construction method is expected to spread in the near future. In this regard, this study seeks to promote more economical and efficient production and supply of modular housing. To this end, it investigates the current status of modular construction, analyzes the problems and proposes a serious of MC design standards as part of the design standardization and open system for modular housing industry to solve the problems.

• 대한건축학회논문집:계획계
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• 제34권6호
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• pp.31-37
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• 2018

With the progress of national policy researches on the modular construction, many studies have been conducted regarding the standardization of interior building materials. However, studies on the standardization of exterior building materials are still insufficient, and there are no dedicated exterior materials for modular construction. In this regard, this study investigated the necessary of standardization through the analysis on 7 kinds of exterior materials used in general buildings and exterior building materials applied to modular apartment houses in order to establish design criteria for the standardization of dedicated modular exterior materials. Based on the analysis results, assembly reference plane in conjunction with inside dimensions was set, and panelizing standardized in five parts was proposed to solve the problem of low exterior material standardization rate. It also proposed elastic gasket and steel bracket details that can compensate for the fabrication errors of unit boxes and construction errors in stacking.

• 대한건축학회논문집:계획계
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• 제35권6호
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• pp.39-46
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• 2019

In the 21st century, medical facility projects are required to operate appropriate digital technologies as the development of technology and the interests of various participants become more complex. In order for architects to successfully lead negotiations among various stakeholder groups, it is necessary to plan for effective communication through appropriate design reflecting their opinions and coordination of conflicts. For this purpose, building information modeling (BIM), which is a method of designing based on knowledge information related to medical facilities in the building database, can respond to change of order promptly and minimizes the occurrence of design errors can do. Recently, BIM technology and cloud computing technology in ICT have been combined and research on cloud BIM has been actively carried out. The use of cloud computing technology in BIM-based healthcare facility projects can effectively support decision making among project participants and has the advantage of sharing and collaborating on various forms of information generated during the design process, regardless of location and time. Therefore, the purpose of this study is to build of system that can support the design of medical facility using cloud computing technology in BIM.

• 대한건축학회논문집:계획계
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• 제35권5호
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• pp.85-94
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• 2019

The modular apartment has been completed for the first time in Korea through the national research and development (R&D) project in December 2017, and 30 households moved in. Although conditions such as technicality and constructability have to be satisfied to adopt and spread the modular apartments in the future, economic feasibility is the most important factor among the conditions. The economic feasibility of modular apartments can be compared with that of existing reinforced concrete (RC) structure apartments. It is highly important to reduce the construction cost through standardization above all. The standardization refers to establishment of national design standards and principles, and it is important for manufacturers and building companies to comply with those standards and principles. The modular construction (MC) skill in Korea is at an early adoption stage and the MC market is not widely expanded yet. Thus, the application of the MC design, which is the basis of the standardization, has not been widely accepted. However, related R&D projects are now performing mainly by the Ministry of Land, Infrastructure, and Transport to promote modular apartments in recent years and the design standardization standard (draft) is now prepared to be notified as a result of the steady research. Furthermore, pilot complexes for demonstration purpose are under construction, starting from public rental apartments. Thus, MC method-applied public rental houses will be spread in near future. This study aims to investigate the current design status in the Ga-Yang Housing as a pilot modular complex to produce and supply more economical and efficient modular houses, and analyze the problems by comparing the design standardization standards with pre-notified design standardization standards and summarize the modifications between them thereby presenting foundational data for establishment of the design standardization in the modular business industry.

• 한국안광학회지
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• 제20권3호
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• pp.385-390
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• 2015

목적: 본 연구는 원거리 Randot 입체검사(Distance Randot Stereotest, STEREO OPTICAL. Co., Inc. USA)를 이용한 정적 입체시(static stereoacuity)와 삼간계(three-rods test, iNT, Korea)를 이용한 동적 입체시(dynamic stereoacuity)를 평가해보고, 두 입체시의 기준과 상관관계, 두 검사법의 유용성에 대하여 알아보았다. 방법: 평균연령 20.88세(19~32세)인 정상 성인 109명(남자 61명, 여자 48명)을 대상으로 원거리 Randot 입체검사는 검사거리 3 m에서 정적 입체시를, 삼간계는 2.5 m에서 동적 입체시를 측정하였다. 결과: 원거리 정적 입체시는 평균 $155.77{\pm}133.11$초, 동적 입체시는 평균 오차거리 $11.13{\pm}9.69mm$, 등가 환산 입체시 $23.44{\pm}20.96$초로 두 입체시는 통계적으로 유의한 차이가 있었고(p=0.00), 상관성은 비교적 낮았다(${\rho}=0.226$). 동적 입체시의 경우 오차거리 20 mm를 기준으로 정상범위로 구분하였을 때, 97명(89%)에서 20 mm 이하의 오차거리가 나타났고 이들의 평균 오차거리는 $8.43{\pm}5.10mm$, 환산 평균 동적 입체시는 $17.68{\pm}10.67$초였다. 오차거리 20 mm는 등가 환산 동적 입체시 40.99초(PD 62 mm 기준)이다. 결론: 정적 입체시와 동적 입체시의 상관성은 매우 적어 서로 다른 기능으로 구분하여 검사법을 적용하여야 한다. 원거리 Randot 입체검사는 단안단서가 배제된 정적 입체시를, 삼간계는 단안단서가 존재하는 일상생활의 자연시 상태에서 눈과 손의 협응반응이 포함된 동적 입체시를 측정할 수 있어 두 입체시의 기준을 마련하는데 적절하며, 두 검사법을 병행 사용함이 유용하다고 사료된다. 삼간계 동적 입체시는 성인의 정상범위를 오차거리 20 mm를 기준으로 구분하는 것이 통계적인 관점에서 적합하다고 사료된다.