• 제목/요약/키워드: science modules

검색결과 958건 처리시간 0.022초

반투명 염료감응 태양전지 모듈 연구 (A module of Semitransparent Dye-sensitized Solar Cell)

  • 강만구
    • 통합자연과학논문집
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    • 제2권4호
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    • pp.237-242
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    • 2009
  • As semitransparent dye-sensitized solar cells (DSSCs) have advanced to large-scale applications from lab-level research, the large-scale performance has attracted much attention. Modules of DSSCs have been investigated to optimize the efficiency as a $TiO_2$ systhesis temperature and a surface treatment of $TiCl_4$ aqueous solution. Essentially, these semitransparent modules have an extended structure with lab-scale works with the exception of the dimensions and methods for the series connection. The $5cm{\times}6.5cm$ modules have shown an efficiency of about 6% without a scattering layer. While the fill factors of modules depend on the width of each $TiO_2$ unit cell, they are much less dependent on the lengths of the unit cells.

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Monitoring System of Agriculture Fields using ZigBee Modules

  • Ayurzana, Odgerel;Tsagaanchuluun, Sugir
    • International journal of advanced smart convergence
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    • 제10권1호
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    • pp.89-96
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    • 2021
  • The goal of this study is to develop experiment monitoring system of agriculture fields using ZigBee wireless modules. Soil moisture, ambient temperature, atmospheric pressure and intensity of sunlight are the most important factorsto grow a wheat crop and other vegetables. In orderto monitorthe factorssoil moisture (YL69), air pressure (BMP180), temperature (DS18B20), photoresistor were used for sensing environment data. The TI CC2530 RF SoC chip was used in the system. ZigBee modules were connected to star topology. ZigBee modules send data wirelessly to a data center. This data can be displayed and analyzed on the main monitoring program as needed also sent to the client mobile. Characteristics of the sensors were determined by experiment results.

LOCAL-GLOBAL PRINCIPLE AND GENERALIZED LOCAL COHOMOLOGY MODULES

  • Bui Thi Hong Cam;Nguyen Minh Tri;Do Ngoc Yen
    • 대한수학회논문집
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    • 제38권3호
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    • pp.649-661
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    • 2023
  • Let 𝓜 be a stable Serre subcategory of the category of R-modules. We introduce the concept of 𝓜-minimax R-modules and investigate the local-global principle for generalized local cohomology modules that concerns to the 𝓜-minimaxness. We also provide the 𝓜-finiteness dimension f𝓜I (M, N) of M, N relative to I which is an extension the finiteness dimension fI (N) of a finitely generated R-module N relative to I.

INJECTIVE PROPERTY RELATIVE TO NONSINGULAR EXACT SEQUENCES

  • Arabi-Kakavand, Marzieh;Asgari, Shadi;Tolooei, Yaser
    • 대한수학회보
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    • 제54권2호
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    • pp.559-571
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    • 2017
  • We investigate modules M having the injective property relative to nonsingular modules. Such modules are called "$\mathcal{N}$-injective modules". It is shown that M is an $\mathcal{N}$-injective R-module if and only if the annihilator of $Z_2(R_R)$ in M is equal to the annihilator of $Z_2(R_R)$ in E(M). Every $\mathcal{N}$-injective R-module is injective precisely when R is a right nonsingular ring. We prove that the endomorphism ring of an $\mathcal{N}$-injective module has a von Neumann regular factor ring. Every (finitely generated, cyclic, free) R-module is $\mathcal{N}$-injective, if and only if $R^{(\mathbb{N})}$ is $\mathcal{N}$-injective, if and only if R is right t-semisimple. The $\mathcal{N}$-injective property is characterized for right extending rings, semilocal rings and rings of finite reduced rank. Using the $\mathcal{N}$-injective property, we determine the rings whose all nonsingular cyclic modules are injective.

COFINITENESS OF GENERAL LOCAL COHOMOLOGY MODULES FOR SMALL DIMENSIONS

  • Aghapournahr, Moharram;Bahmanpour, Kamal
    • 대한수학회보
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    • 제53권5호
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    • pp.1341-1352
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    • 2016
  • Let R be a commutative Noetherian ring, ${\Phi}$ a system of ideals of R and $I{\in}{\Phi}$. In this paper among other things we prove that if M is finitely generated and $t{\in}\mathbb{N}$ such that the R-module $H^i_{\Phi}(M)$ is $FD_{{\leq}1}$ (or weakly Laskerian) for all i < t, then $H^i_{\Phi}(M)$ is ${\Phi}$-cofinite for all i < t and for any $FD_{{\leq}0}$ (or minimax) submodule N of $H^t_{\Phi}(M)$, the R-modules $Hom_R(R/I,H^t_{\Phi}(M)/N)$ and $Ext^1_R(R/I,H^t_{\Phi}(M)/N)$ are finitely generated. Also it is shown that if cd I = 1 or $dimM/IM{\leq}1$ (e.g., $dim\;R/I{\leq}1$) for all $I{\in}{\Phi}$, then the local cohomology module $H^i_{\Phi}(M)$ is ${\Phi}$-cofinite for all $i{\geq}0$. These generalize the main results of Aghapournahr and Bahmanpour [2], Bahmanpour and Naghipour [6, 7]. Also we study cominimaxness and weakly cofiniteness of local cohomology modules with respect to a system of ideals.

MAX-INJECTIVE, MAX-FLAT MODULES AND MAX-COHERENT RINGS

  • Xiang, Yueming
    • 대한수학회보
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    • 제47권3호
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    • pp.611-622
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    • 2010
  • A ring R is called left max-coherent provided that every maximal left ideal is finitely presented. $\mathfrak{M}\mathfrak{I}$ (resp. $\mathfrak{M}\mathfrak{F}$) denotes the class of all max-injective left R-modules (resp. all max-flat right R-modules). We prove, in this article, that over a left max-coherent ring every right R-module has an $\mathfrak{M}\mathfrak{F}$-preenvelope, and every left R-module has an $\mathfrak{M}\mathfrak{I}$-cover. Furthermore, it is shown that a ring R is left max-injective if and only if any left R-module has an epic $\mathfrak{M}\mathfrak{I}$-cover if and only if any right R-module has a monic $\mathfrak{M}\mathfrak{F}$-preenvelope. We also give several equivalent characterizations of MI-injectivity and MI-flatness. Finally, $\mathfrak{M}\mathfrak{I}$-dimensions of modules and rings are studied in terms of max-injective modules with the left derived functors of Hom.

공정의 안전 검증을 위한 PLC 모듈 개발 (Development of PLC modules for the safety verification of chemical processes)

  • 정상헌;이광순;문일
    • 제어로봇시스템학회논문지
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    • 제2권1호
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    • pp.53-59
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    • 1996
  • An automatic verification method has been studied to determine the safety and operability of programmable logic controller (PLC) based systems. For the systematic and efficient verification, we have developed a conversion method from relay ladder logic (RLL) to the verification system description. RLL is a common representation used to document PLC programs for the sequential logic of the system such as the safety interlocks and the startup/shutdown procedures. Once the modules are developed, complex RLLs can be represented by the combination of modules. As a result we can verify complex PLC systems using the verification method including RLL modules. The developed modules are used to verify alarm systems and show that the method is valid.

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Enhancing Performance with a Learnable Strategy for Multiple Question Answering Modules

  • Oh, Hyo-Jung;Myaeng, Sung-Hyon;Jang, Myung-Gil
    • ETRI Journal
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    • 제31권4호
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    • pp.419-428
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    • 2009
  • A question answering (QA) system can be built using multiple QA modules that can individually serve as a QA system in and of themselves. This paper proposes a learnable, strategy-driven QA model that aims at enhancing both efficiency and effectiveness. A strategy is learned using a learning-based classification algorithm that determines the sequence of QA modules to be invoked and decides when to stop invoking additional modules. The learned strategy invokes the most suitable QA module for a given question and attempts to verify the answer by consulting other modules until the level of confidence reaches a threshold. In our experiments, our strategy learning approach obtained improvement over a simple routing approach by 10.5% in effectiveness and 27.2% in efficiency.

PromoterWizard: An Integrated Promoter Prediction Program Using Hybrid Methods

  • Park, Kie-Jung;Kim, Ki-Bong
    • Genomics & Informatics
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    • 제9권4호
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    • pp.194-196
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    • 2011
  • Promoter prediction is a very important problem and is closely related to the main problems of bioinformatics such as the construction of gene regulatory networks and gene function annotation. In this context, we developed an integrated promoter prediction program using hybrid methods, PromoterWizard, which can be employed to detect the core promoter region and the transcription start site (TSS) in vertebrate genomic DNA sequences, an issue of obvious importance for genome annotation efforts. PromoterWizard consists of three main modules and two auxiliary modules. The three main modules include CDRM (Composite Dependency Reflecting Model) module, SVM (Support Vector Machine) module, and ICM (Interpolated Context Model) module. The two auxiliary modules are CpG Island Detector and GCPlot that may contribute to improving the predictive accuracy of the three main modules and facilitating human curator to decide on the final annotation.