• Title/Summary/Keyword: Nagaoka

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Measurement of the Anticlinic Coupling Coefficient of an Antiferroelectric Liquid Crystal

  • Kang, Dae-Seung;Kimura, Munehiro
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.487-490
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    • 2002
  • In this paper, we report a novel way to evaluate the anticlinic interlayer coupling coefficient U between smectic layers of an antiferroelectric liquid crystal, by utilizing a small field-induced perturbation of the molecular orientation. U was found to exhibit an unusual "S-shaped" dependence on temperature, with values ranging between $0.4{\times}10^4$ and $0.4{\times}10^{-1}$ erg $cm^{-3}$ over a 10$^{\circ}C$ temperature range below smectic A-smectic $C_A$ phase transition temperature. The results are good agreement with estimates for U based upon the threshold field for the onset of solitary waves, and provide strong supporting the low-field regime for the single Fourier component model.

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Borehole radar monitoring of infiltration processes in a vadose zone

  • Jang, Han-Nu-Ree;Park, Mi-Kyung;Kuroda, Seiichiro;Kim, Hee-Joon
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.313-316
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    • 2007
  • Ground-penetrating radar (GPR) is an effectiveness tool for imaging spatial distribution of hydrogeologic parameters. An artificial groundwater recharge test has been conducted in Nagaoka City in Japan, and time-lapse crosshole GPR data were collected to monitor infiltration processes in a vadose zone. Since radiowave velocities in a vadose zone are largely controlled by variations in water content, the increase in traveltimes is interpreted as an increase in saturation in the test zone. We use a finite-difference time-domain method in two-dimensional cylindrical coordinates to simulate field results. Numerical modeling successfully reproduces the major feature of velocity changes in the filtration process.

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Effects of Catalyst Promotion on the Selective Hydrogenation of Biphenol Using Various Pd/C Catalysts

  • Cho, Hong-Baek;Hong, Bum-Eui;Park, Jai-Hyun;Ahn, Sung-Hyun;Park, Yeung-Ho
    • Bulletin of the Korean Chemical Society
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    • v.29 no.12
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    • pp.2434-2440
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    • 2008
  • The effect of sodium (Na) promotion was studied in the biphenol (BP) hydrogenation using various Pd/C catalysts. Different amounts of sodium metal were used for promotion with Pd/C and their effects on BP hydrogenation were observed. The promotion order was changed to compare the effect of the position of the promoter in relation to the palladium (Pd) metal on the catalytic activity and yield of the final product, bicyclohexyl-4,4'-diol (BHD). Pd/C catalysts prepared from different methods were also sodium-promoted and the changes of the reaction pathway according to the type of promoted Pd/C catalyst were compared.

Shape determination of 3-D reinforcement corrosion in concrete based on observed temperature on concrete surface

  • Kurahashi, Takahiko;Oshita, Hideki
    • Computers and Concrete
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    • v.7 no.1
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    • pp.63-81
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    • 2010
  • We present the shape determination method of 3-D reinforcement corrosion based on observed temperature on concrete surface. The non-destructive testing for reinforcement corrosion in concrete using a heat image on concrete surface have been proposed by Oshita. The position of the reinforcement of corrosion or the cavity can be found using that method. However, the size of those defects can not be precisely measured based on the heat image. We therefore proposed the numerical determination system of the shape for the reinforcement corrosion using the observed temperature on the concrete surface. The adjoint variable method is introduced to formulate the shape determination problem, and the finite element method is employed to simulate the heat transfer problem. Some numerical experiments and the examination for the number of the observation points are shown in this paper.

Static behaviors of self-anchored and partially earth-anchored long-span cable-stayed bridges

  • Xie, Xu;Yamaguchi, Hiroki;Nagai, Masatsugu
    • Structural Engineering and Mechanics
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    • v.5 no.6
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    • pp.767-774
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    • 1997
  • In this paper, three dimensional static behaviors of the self-anchored and partially earth-anchored cable-stayed bridges, with a span of 1400 meters, under wind loading are studied by using a 3D geometrical nonlinear analysis. In this analysis, the bridges both after completion and under construction are dealt with. The wind resistant characteristics of the both cable-stayed systems are made clear. In particular, the characteristics of the partially earth-anchored cable systems, which is expected to be a promising solution for extending the span of the cable-stayed systems further, is presented.

Resolution of Time and Worker Conflicts for a Single Project in a Max-Plus Linear Representation

  • Yoshida, Shotaro;Takahashi, Hirotaka;Goto, Hiroyuki
    • Industrial Engineering and Management Systems
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    • v.10 no.4
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    • pp.279-287
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    • 2011
  • This research develops a framework for resolving time and worker conflicts in the Critical Chain Project Management (CCPM) method, expressed in the form of a Max-Plus Linear (MPL) system. Our previous work proposed a method for resolving time conflicts. However, in practical cases, both time and worker conflicts may occur. Hence, we propose a method for resolving both time and worker conflicts for a single project. We first consider how to detect a resource conflict. Then, we define an adjacency matrix to resolve the detected conflicts. Using the proposed method, we confirm that the resource conflict can be resolved through a numerical example.

Room Temperature Preparation of Poly-Si Thin Films by IBE with Substrate Bias Method

  • Cho, Byung-Yoon;Yang, Sung- Chae;Han, Byoung-Sung;Lee, Jung-Hui;Yatsui Kiyoshi
    • Transactions on Electrical and Electronic Materials
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    • v.6 no.2
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    • pp.57-62
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    • 2005
  • Using intense pulsed ion beam evaporation technique, we have succeeded in the preparation of poly crystalline silicon thin films without impurities on silicon substrate. Good crystallinity and high deposition rate have been achieved without heating the substrate by using lEE. The crystallinity of poly-Si film has been improved with the high density of the ablation plasma. The intense diffraction peaks of poly-Si thin films could be obtained by using the substrate bias system. The crystallinity and the deposition rate of poly-Si thin films were increased by applying (-) bias voltage for the substrate.

International developments in geological storage of $CO_2$ ($CO_2$의 지질학적인 저장에 있어서의 국제적인 개발들)

  • Freund, Paul
    • Geophysics and Geophysical Exploration
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    • v.9 no.1
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    • pp.1-9
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    • 2006
  • Geological storage of captured $CO_2$ is a new way of reducing greenhouse gas emissions to protect the climate, but is based on the established technology associated with injection of fluids underground. The geological formations of interest for this technique include operational and depleted oil and gas fields, and deep saline aquifers. Prediction of storage performance will depend on models of the behaviour of $CO_2$ in geological formations; these need to be refined and verified, and methods of monitoring developed and proved. These needs can be met through monitored demonstration and research projects. Current commercial projects that are demonstrating $CO_2$ storage include Sleipner, Weyburn, ORC, and In Salah; research projects include West Pearl Queen, Nagaoka, and Frio. In this paper, some of the monitored injection projects are described. The reservoirs employed for storing $CO_2$, and the associated monitoring techniques, are briefly reviewed. It is argued that small-scale research projects, used to develop techniques and prove models, are complementary to the large-scale monitored injections that will establish the viability of this technique for mitigating climate change.

Endoscopic Findings and Treatment of Gastric Neoplasms in Familial Adenomatous Polyposis

  • Sato, Chihiro;Takahashi, Kazuya;Sato, Hiroki;Naruse, Takumi;Nakajima, Nao;Takatsuna, Masafumi;Mizuno, Ken-ichi;Hashimoto, Satoru;Takeuchi, Manabu;Yokoyama, Junji;Kobayashi, Masaaki;Terai, Shuji
    • Journal of Gastric Cancer
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    • v.22 no.4
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    • pp.381-394
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    • 2022
  • Purpose: Gastric neoplasia is a common manifestation of familial adenomatous polyposis (FAP). This study aimed to elucidate the clinical characteristics, endoscopic features including fundic gland polyposis (FGPsis), and treatment outcomes of gastric neoplasms (GNs) in patients with FAP. Materials and Methods: A total of 35 patients diagnosed with FAP, including nine patients from four pedigrees who underwent esophagogastroduodenoscopy (EGD), were investigated regarding patient characteristics, GN morphology, and treatment outcomes. Results: Twenty-one patients (60.0%) had 38 GNs; 33 (86.8%) and 5 (13.2%) were histologically diagnosed with adenocarcinoma and adenoma, respectively. There were no specific patient characteristics related to GNs.Nodule-type GNs were more prevalent in patients with FGP than without (52.2% vs. 0.0%, P=0.002) in the upper body of the stomach. Conversely, depressed-type GNs were fewer in patients with FGPsis than in those without (13.0% vs. 73.3%, P<0.001). Slightly elevated-type GNs were observed in both groups (34.8% vs. 20.0%, P=0.538). Even within pedigrees, the background gastric mucosa and types of GNs varied. In total, 24 GNs were treated with endoscopic submucosal dissection (ESD) and eight with endoscopic mucosal resection (EMR). EMR was selected for GNs with FGPsis because of the technical difficulty of ESD, resulting in a lower en bloc resection rate (62.5% vs. 100%, P=0.014). Conclusions: Our study indicates the necessity of routine EGD surveillance in patients diagnosed with FAP. Notably, the morphology and location of GNs differed between patients with and without FGPsis. Endoscopic treatment and outcomes require more attention in cases of FGPsis.

Glucose Sensors Using Lipoic Acid Self-Assembled Monolayers

  • Kim, Ji Yeong;Nakayama, Tadachika;Kim, Jae-Hun;Kim, Sang Sub
    • Journal of Sensor Science and Technology
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    • v.23 no.5
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    • pp.295-298
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    • 2014
  • A novel approach to fabricating high-performance glucose sensors is reported, which is based on the process of self-assembled monolayers (SAMs). In this study, we have particularly used ${\alpha}$-lipoic acid (LA) SAMs for the glucose sensors. To our best knowledge, this study is the first one to use LA as SAMs for this purpose. N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) were deliberately attached at the same time on the LA SAM. Then, glucose oxidase ($GO_X$) and horseradish peroxidase (HRP) were sequentially immobilized. Thus, the HRP/$GO_X$/NHS-EDC/LA-SAM/Au/Cr/glass working electrode was developed. The glucose-sensing capability of the fabricated sensor was systematically measured by the use of cyclic voltammetry in the range of 1-30 mM glucose in phosphate-buffered saline. The result showed a good sensitivity, that is, as high as $27.5{\mu}A/(mM{\cdot}cm^2)$. This result conspicuously demonstrates that LA can be one of promising substances for use as SAMs for accurately monitoring trace levels of glucose concentration in human blood.