• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.63-73
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• 2010

A comprehensive mapping project for agroclimatic zoning in South Korea will end by April 2010, which has required 4 years, a billion won (ca. 0.9 million US dollars) and 22 experts from 7 institutions to complete it. The map database from this project may be categorized into primary, secondary and analytical products. The primary products are called "high definition" digital climate maps (HD-DCMs) and available through the state of the art techniques in geospatial climatology. For example, daily minimum temperature surfaces were prepared by combining the climatic normals (1971-2000 and 1981-2008) of synoptic observations with the simulated thermodynamic nature of cold air by using the raster GIS and microwave temperature profiling which can quantify effects of cold air drainage on local temperature. The spatial resolution of the gridded climate data is 30m for temperature and solar irradiance, and 270m for precipitation. The secondary products are climatic indices produced by statistical analysis of the primary products and includes extremes, sums, and probabilities of climatic events relevant to farming activities at a given grid cell. The analytical products were prepared by driving agronomic models with the HD-DCMs and dates of full bloom, the risk of freezing damage, and the fruit quality are among the examples. Because the spatial resolution of local climate information for agronomic practices exceeds the current weather service scale, HD-DCMs and the value-added products are expected to supplement the insufficient spatial resolution of official climatology. In this lecture, state of the art techniques embedded in the products, how to combine the techniques with the existing geospatial information, and agroclimatic zoning for major crops and fruits in South Korea will be provided.

• Journal of the Korean Mathematical Society
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• v.55 no.1
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• pp.225-251
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• 2018

The m-isometry of a single operator in Agler and Stankus [3] was naturally generalized to the m-isometric tuple of several commuting operators by Gleason and Richter [22]. Some examples of m-isometric tuples including the recently much studied Arveson-Drury d-shift were given in [22]. We provide more examples of m-isometric tuples of operators by using sums of operators or products of operators or functions of operators. A class of m-isometric tuples of unilateral weighted shifts parametrized by polynomials are also constructed. The examples in Gleason and Richter [22] are then obtained by choosing some specific polynomials. This work extends partially results obtained in several recent papers on the m-isometry of a single operator.

• Bulletin of the Korean Mathematical Society
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• v.54 no.2
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• pp.443-454
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• 2017

We study a notion of q-frequent hypercyclicity of linear maps between the Banach algebras consisting of operators on a separable infinite dimensional Banach space. We derive a sufficient condition for a linear map to be q-frequently hypercyclic in the strong operator topology. Some properties are investigated regarding q-frequently hypercyclic subspaces as shown in [5], [6] and [7]. Finally, we study q-frequent hypercyclicity of tensor products and direct sums of operators.

• Journal of the Korean Chemical Society
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• v.7 no.1
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• pp.38-41
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• 1963

Nb is one of the trouble-some fission products in the reprocessing of nuclear fuels. In this paper, the extraction of Nb from 1, 2, 3, 4, 6 and 9N $HNO_3$ solution by mixtures of TBP and DBP in dodecane are reported. Sums of the concentration of TBP and DBP are kept to 20%. When the concentrations of DBP are lower the $2{\times}10^{-2}%$, distribution ratios are almost same, and ratios increase abruptly and the slope is about 2.5 at between $2{\times}10^{-2}$ to $4{\times}10^{-1}%$, then slope falls down to about 0.5. There is aging effect on mixture of TBP and DBP.

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.100-104
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• 1998

This paper describes the real-time implementation of an adaptive controller fur the robotic manipulator. Digital signal processors(DSPs) are special purpose micro-processors that are particularly powerful for intensive numerical computations involving sums and products of variables. TMS320C50 chips are used in implementing real time adaptive control algorithms to provide an enhanced motion for robotic manipulators. In the proposed scheme, adaptation laws are derived from the improved Lyapunov second stability analysis based on the direct adaptive control theory. The adaptive controller consists of an adaptive feedforward controller and feedback controller. The proposed control scheme is simple in structure, fast in computation, and suitable for real-time control. Moreover, this scheme does not require any accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a assembling robot.

• Bulletin of the Korean Mathematical Society
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• v.38 no.2
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• pp.399-412
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• 2001

In this paper, we consider that the q-analogue of w$\omega-Bernoulli numbers\; B_i(\omega, q)$. And we calculate the sums of products of two q-analogue of $\omega-Bernoulli numbers B_i(\omega, q)$ in complex cases. From this result, we obtain the Euler type formulas of the Carlitz´s q-Bernoulli numbers $\beta_i(q)$ and q-Bernoulli numbers $B_i(q)$. And we also calculate the p-adic Stirling type series by the definition of $B_i(\omega, q)$ in p-adic cases.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.2
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• pp.83-88
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• 2007

본 논문에서 선형함수의 곱의 형태로 표현된 비선형 함수를 목적식 또는 제약식에 가지는 비선형 최적화 문제를 새로운 변수를 추가하여 선형 Relaxation 최적화 문제로 Reformulation 하는 기법을 소개한다. 특히, 선형함수의 곱의 형태를 가지는 비선형 함수를 포함하는 비선형 정수 최적화 문제를 선형 정수 최적화 문제로 Relaxation할 경우 두 최적화 문제의 해가 일치함을 보인다. 또한 소개된 Relaxation 기법을 응용하여, 추가되는 변수의 수를 증가시킴으로서, 보다 Tight한 Relaxation 문제를 도출하는 과정에 대하여 소개한다.

• Bulletin of the Korean Mathematical Society
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• v.31 no.1
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• pp.93-97
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• 1994

Previously T.Porter [3] has given a relative Chinese Remainder Theorem under the hypothesis that given ring R has at least one .tau.-closed maximal ideal (by his notation Ma $x_{\tau}$(R).neq..phi.). In this short paper we drop his overall hypothesis that Ma $x_{\tau}$(R).neq..phi. and give the proof and some related results with this Theorem. In this paper R will always denote a commutative ring with identity element and all modules will be unitary left R-modules unless otherwise specified. Let .tau. be a given hereditarty torsion theory for left R-module category R-Mod. The class of all .tau.-torsion left R-modules, dented by J is closed under homomorphic images, submodules, direct sums and extensions. And the class of all .tau.-torsionfree left R-modules, denoted by F, is closed under taking submodules, injective hulls, direct products, and isomorphic copies ([2], Proposition 1.7 and 1.10).

• Proceedings of the KSLP Conference
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• 2003.11a
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• pp.236-236
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• 2003

음성합성을 위한 운율연구는 실험음성학과 음성공학 분야에서 활발히 이루어져 왔고, 가시적인 성과도 거두어 왔다. 최근 운율의 자연성을 향상시키기 위한 노력은 corpus-based unit selection에서와 같이, 대단위 음성자료에 의존하게 되면서 급격한 자연성의 향상을 가져온 것이 사실이지만, 여전히 새로 주어진 자료에 대해서 부자연스러운 운율을 극복해야 한다는 과제를 안고 있다. 이 논문은 길이, 억양, 에너지 등의 운율요소 가운데, 우선적으로 분절음의 길이에 초점을 두고, 대규모 음성자료를 바탕으로 한 자료기반형 길이예측모델을 지양하고 언어학적 지식과 언어자질을 이용한 지식기반형 길이예측모델을 제시하고자 한다. 모델링을 위한 방법으로는, 기본적으로 자료기반형 모델링 기법이지만 언어자질을 이용한 길이예측이 가능한 Classification and Regression Tree (CART) 모델링과 전통적인 지식기반형 모델링인 sequential rule systems을 확대시킨 Sums-of-Products 모델링을 사용한다. (중략)

• Journal of the Korean Mathematical Society
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• v.56 no.2
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• pp.539-558
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• 2019

An ideal of a commutative ring is called a d-ideal if it contains the annihilator of the annihilator of each of its elements. Denote by DId(A) the lattice of d-ideals of a ring A. We prove that, as in the case of f-rings, DId(A) is an algebraic frame. Call a ring homomorphism "compatible" if it maps equally annihilated elements in its domain to equally annihilated elements in the codomain. Denote by $SdRng_c$ the category whose objects are rings in which the sum of two d-ideals is a d-ideal, and whose morphisms are compatible ring homomorphisms. We show that $DId:\;SdRng_c{\rightarrow}CohFrm$ is a functor (CohFrm is the category of coherent frames with coherent maps), and we construct a natural transformation $RId{\rightarrow}DId$, in a most natural way, where RId is the functor that sends a ring to its frame of radical ideals. We prove that a ring A is a Baer ring if and only if it belongs to the category $SdRng_c$ and DId(A) is isomorphic to the frame of ideals of the Boolean algebra of idempotents of A. We end by showing that the category $SdRng_c$ has finite products.