• Geomechanics and Engineering
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• 제16권2호
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• pp.125-140
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• 2018

Tianjin, which is located on the west shore of the Bohai Sea, is part of China's Circum-Bohai-Sea Region, where very weak clay is deposited. From the 1970s to the early $21^{st}$ century, Tianjin marine clay deposits have been the subject of numerous geotechnical investigations. Because of these deposits' geological complexity, great depositional thickness, high water content, large void ratio, excessive settlement, and low shear strength, the geotechnical properties of Tianjin marine clay need to be summarized and evaluated based on various in situ and laboratory tests so that Tianjin can safely and economically sustain more infrastructure in the coming decades. In this study, the properties of Tianjin marine clay, especially its consolidation properties, are summarized, evaluated and discussed. The focus is on establishing correlations between the geotechnical property indexes and mechanical parameters of Tianjin marine clay. These correlations include the correlations between the water content and the void ratio, the depth and the undrained shear strength, the liquid limit and the compression index, the tip resistance and the constrained modulus, the plasticity index and the ratio of undrained shear strength and the preconsolidation pressure. In addition, the primary consolidation properties of Tianjin marine clay, such as the intrinsic compression line (ICL), sedimentation compression line (SCL), compression index, $C_c$, coefficient of consolidation, $C_v$, and hydraulic conductivity change index, $C_{kv}$, are evaluated and discussed. A secondary consolidation property, i.e., the secondary compression index, $C_a$, is also investigated, and the results show that the ratio of $C_a/C_c$ for Tianjin marine clay can be used to calculate $C_a$ in secondary consolidation settlement predictions.

• 한국미생물·생명공학회지
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• 제15권6호
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• pp.414-419
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• 1987

Saccharomycopsis lipolytica의 isocitrate lyase에 대한 온도감수성 변이의 특성과 이 효소의 생화학적성질을 조사하기 위한 기초연구로서 isocitrate lyase 결손변이 균주인 MX9-11(Icl-)로부터 온도감수성을 나타내는 복귀 변이균주를 3균주 분리하고 그중 활성의 회복이 가장 높은 MX9-11RX8 균주의 성질을 조사하였다. MX9-11RX8 복귀 변이균주는 탄소원으로서 초산을 사용하였을 때 온도의 증가에 따라서 isocitrate lyase의 생성량과 비생성 속도가 감소하여 33$^{\circ}C$에서는 거의 효소를 합성하지 않았으며, 온도를 23$^{\circ}C$에서 33$^{\circ}C$로 올렸을 때 효소의 합성은 바로 정지하였지만 균체증식은 계속되었다. 한편 n-hexadecane을 탄소원으로 사용하였을 때에도 온도감수성을 나타내었으며, 온도의 shift up 후에도 isocitric acid 생산은 거의 변화가 없었다.

• The Plant Pathology Journal
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• 제29권3호
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• pp.249-259
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• 2013

Burkholderia glumae causes rice grain rot and sheath rot by producing toxoflavin, the expression of which is regulated by quorum sensing (QS). The QS systems of B. glumae rely on N-octanoyl homoserine lactone, synthesized by TofI and its cognate receptor TofR, to activate the genes for toxoflavin biosynthesis and an IclR-type transcriptional regulator gene, qsmR. To understand genome-wide transcriptional profiling of QS signaling, we employed RNAseq of the wild-type B. glumae BGR1 with QS-defective mutant, BGS2 (BGR1 tofI::${\Omega}$) and QS-dependent transcriptional regulator mutant, BGS9 (BGR1 qsmR::${\Omega}$). A comparison of gene expression profiling among the wild-type BGR1 and the two mutants before and after QS onset as well as gene ontology (GO) enrichment analysis from differential expressed genes (DEGs) revealed that genes involved in motility were highly enriched in TofI-dependent DEGs, whereas genes for transport and DNA polymerase were highly enriched in QsmR-dependent DEGs. Further, a combination of pathways with these DEGs and phenotype analysis of mutants pointed to a couple of metabolic processes, which are dependent on QS in B. glumae, that were directly or indirectly related with bacterial motility. The consistency of observed bacterial phenotypes with GOs or metabolic pathways in QS-regulated genes implied that integration RNAseq with GO enrichment or pathways would be useful to study bacterial physiology and phenotypes.

• 천문학회보
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• 제36권2호
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• pp.121-121
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• 2011

Thanks to KMTNet's wide field of view, it is time to implement imaging survey of extensive area of clusters of galaxies in the southern sky with modern instrument. As part of potential long-term survey of nearby (D < 50 Mpc) well-known clusters of galaxies, we propose a wide-field and deep survey of Fornax cluster as a first step of the project. By imaging the 400 square deg region (100 fields) enclosed within the five times virial radius of the Fornax cluster, in three SDSSfilters(g', r', i'), we can provide an unprecedented view of structure of Fornax cluster using sample from giant to dwarf galaxies. We will secure galaxies with brightness comparable to the limiting magnitude (r'=23.1 AB mag) of SDSS. Furthermore, we also request extremely deep (limiting surface brightness of ~ 28 mag $arcsec^{-2}$forr'band) survey for the central region (16 square degree, i.e., four fields) of Fornax cluster. This will allow us to detect the diffuse intracluster light (ICL) that permeates clusters as a valuable tool for studying the hierarchical nature of cluster assembly. In order to complete whole survey, about 285 hr observing time (without overhead) is required. By combining data available at other wavelengths, it will offer unique constraints on the formation of large-scale structure and also provide important clues for theories of galaxy formation and evolution. Our proposed survey will be implemented in the close collaboration with researchers in various countries (Germany, Australia, UK, USA) and ongoing project (e.g., SkyMapper).

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권8호
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• pp.348-353
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• 2003

This paper was the research of high voltage suspension insulator (400 [kN]) including pottery stone, feldspar, clay and alumina of 17 [wt%]. The slurry was fabricated after ball milling mixed raw materials. Green compacts were made by the extrusion of jiggering method and were sintered at 1300[$^{\circ}C$] for 50 [min.] in the tunnel kiln. The sintered density was reached to 97% of theoretical density, and the bending strength was 1658 [k $g_{f}$/$\textrm{cm}^2$] and hardness and fracture toughness which was measured by ICL( indentation crack length ) method were 1658 (kgf/$\textrm{cm}^2$) and 27.5 [Gpa], respectively. In measurement of tana and insulation break voltage of 400 (kN) porcelain, tan$\delta$ took some numerical value between 17${\times}$10$_{-3}$ and 61${\times}$10$_{-3}$ and insulation break voltage value was 19.9$\pm$1.4 [㎸/mm]. The test was performed to research whether the shape of pin affect a overvoltage break load or not As a consequence, when a pin was designed a pin diameter 51 [mm] with the bottom form of two-step constructed with straight in the suspension insulator, Insulator showed overvoltage break load 52 [ton] of the highest value and reflected a fine characteristic in aged deterioration test which is one of the accelerated aging test. Also it could be confirmed a fine characteristic through performing the test that electrical property of insulator was established correctly in accordance with IEC 60383-1 standards.s.

• 대한화학회지
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• 제9권4호
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• pp.153-160
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• 1965

벤젠과 요오드, 브롬, 염소 또는 일브롬화요오드와의 각 系를 사염화탄소 용액에서 分光光度法에 의하여 연구한 결과 $C_6H_6{\cdot}X_2$ 또는 $C_6H_6{\cdot}IX$형의 錯物이 형성됨을 알았다(X는 할로겐 原子를 표시함). 이들 錯物의 생성에 대한 $25^{\circ}$에서의 평형상수는 다음과 같다. $C_6H_6{\cdot}I_2\;0.173lmole^{-1},\;C_6H_6{\cdot}Br_2\;0,137lmole^{-1},\;C_6H_6{\cdot}Cl_2\;0.0643lmole^{-1},\;C_6H_6IBr\;0.341lmole^{-1}.$ 이 결과와 다른 사람들의 결과를 종합하면 벤젠과의 錯物의 상대적 안정도가 다음 순서로 감소함을 알 수 있다. $ICI>IBr>I_2>Br_2>Cl_2$ 이 순서는 그들의 상대적 산도를 의미하며 할로겐 분자의 편극을 및 할로겐 원자의 전기음성도의 차이에 의하여 설명할 수 있다.

• Journal of Power Electronics
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• 제13권1호
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• pp.139-160
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• 2013

In this paper, an intelligent robust control system (IRCS) for precision tracking control of permanent-magnet synchronous motor (PMSM) servo drives is proposed. The IRCS comprises a recurrent wavelet-based interval type-2 fuzzy-neural-network controller (RWIT2FNNC), an RWIT2FNN estimator (RWIT2FNNE) and a compensated controller. The RWIT2FNNC combines the merits of a self-constructing interval type-2 fuzzy logic system, a recurrent neural network and a wavelet neural network. Moreover, it performs the structure and parameter-learning concurrently. The RWIT2FNNC is used as the main tracking controller to mimic the ideal control law (ICL) while the RWIT2FNNE is developed to approximate an unknown dynamic function including the lumped parameter uncertainty. Furthermore, the compensated controller is designed to achieve $L_2$ tracking performance with a desired attenuation level and to deal with uncertainties including approximation errors, optimal parameter vectors and higher order terms in the Taylor series. Moreover, the adaptive learning algorithms for the compensated controller and the RWIT2FNNE are derived by using the Lyapunov stability theorem to train the parameters of the RWIT2FNNE online. A computer simulation and an experimental system are developed to validate the effectiveness of the proposed IRCS. All of the control algorithms are implemented on a TMS320C31 DSP-based control computer. The simulation and experimental results confirm that the IRCS grants robust performance and precise response regardless of load disturbances and PMSM parameters uncertainties.

• Electronic Materials Letters
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• 제14권6호
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• pp.700-711
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• 2018

CdS synthesized by the chemical bath method at $70^{\circ}C$, has been used as an electron transport layer in the planar structure of the perovskite solar cells. A two-step spin process produced a mixed halide perovskite of $CH_3NH_3PbI_{3-x}Cl_x$ and a mixture of $PbCl_2$ and $PbI_2$ was deposited on CdS, followed by a sub-sequential reaction with MAI ($CH_3NH_3I$). The added $PbCl_2$ to $PbI_2$ in the first spin-step affected the structure, orientation, and shape of lead halides, which varied depending on the content of Cl. A small amount of Cl enhanced the surface morphology and the preferred orientation of $PbI_2$, which led to large and uniform grains of perovskite thin films. In contrast, the high content of Cl produces a new phase PbICl in addition to $PbI_2$, which leads to the small and highly uniform grains of perovskites. An improved surface coverage of perovskite films with the large and uniform grains maximized the performance of perovskite solar cells at 0.1 molar ratio of $PbCl_2$ to $PbI_2$. The depth profiling of elements in both lead halide films and mixed halide perovskite films were measured by Rutherford backscattering spectroscopy, revealing the distribution of chlorine along with the thickness, and providing the basis for the mechanism for enhanced preferred orientation of lead halide and the microstructure of perovskites.

• 한국융합학회논문지
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• 제10권4호
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• pp.183-188
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• 2019

본 연구는 취업후상환대출제도가 재학 중 고등교육비용에 대한 부담경감이라는 소기의 정책목적을 달성하였는지를 상환구조에 초점을 맞추어 분석해 보고, 이에 대한 개선방안을 제시하고자 하였다. 구체적으로는 연도별로 대출자의 상환액과 상환유형에 대한 분석을 진행하는 방법론을 활용하였다. 연구결과 취업후상환대출제도는 예상과는 달리 자발적상환액이 의무적상환액보다 훨씬 많은 것으로 나타났다. 따라서 취업후상환제도의 본래 목적인 의무적상환을 활성화 할 수 있는 다양한 정책개선방안 마련이 필요하다. 이를 위해 본고에서는 상환기준율의 다양화, 대출통합관리제도의 도입, 대출미상환가능성 분석 등과 같은 상환율제고를 위한 제도개선사항을 제시하였다. 또한 저임금공익직종에 대한 상환감면, 직업교육대출시행 등과 같이 대출제도전반에 대한 정책방안도 함께 논증하였다. 이 과정에서 본고는 단순한 이론제시에 그치지 않고 다양한 해외사례를 분석하여 제도개선방안의 실행가능성을 제고하였다는 점에서 정책적 학술적 시사점이 있다.

• 한국의류산업학회지
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• 제23권2호
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• pp.261-272
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• 2021

The purpose of the present study was to evaluate the thermal insulation of air-filled winter jackets according to the amount of air-filler using a thermal manikin. The insulation of these jackets' was compared to a down padded jacket with an identical design and size. The amounts of air-filler were 100% (26,219 cm³), 70% (18,645 cm³), 50% (13,110 cm³), and 0% (0 cm³). The results showed that a clothing insulation (Icl) of 0%, 50%, 70%, and 100% air, and 100% down jackets was 0.208, 0.243, 0.207, 0.176, and 0.315 clo, respectively. In addition, the down jacket with waisttaped had a clothing insulation of 0.369 clo. However, the highest value of clothing insulation per clothing weight was the 50% air-filled jacket in all conditions. In terms of regional power consumption of the thermal manikin, the down jacket consumed less power for the shoulder and chest than the air-filled jackets. In conclusion, in order to maximize the thermal insulation of air-filled jackets, an optimal amount of air-filler, that is, an amount which does not compromise (break) the layer of inner air between the surface of manikin and the lining of the jacket, should be explored. Further studies on lining materials, end-closed design, and changes in thermal insulation under the conditions of strong wind or heavy snow are recommended.