• 대한수학회지
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• 제60권2호
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• pp.407-464
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• 2023

Let R be a commutative ring with identity. The structure theorem says that R is a PIR (resp., UFR, general ZPI-ring, π-ring) if and only if R is a finite direct product of PIDs (resp., UFDs, Dedekind domains, π-domains) and special primary rings. All of these four types of integral domains are Krull domains, so motivated by the structure theorem, we study the prime factorization of ideals in a ring that is a finite direct product of Krull domains and special primary rings. Such a ring will be called a general Krull ring. It is known that Krull domains can be characterized by the star operations v or t as follows: An integral domain R is a Krull domain if and only if every nonzero proper principal ideal of R can be written as a finite v- or t-product of prime ideals. However, this is not true for general Krull rings. In this paper, we introduce a new star operation u on R, so that R is a general Krull ring if and only if every proper principal ideal of R can be written as a finite u-product of prime ideals. We also study several ring-theoretic properties of general Krull rings including Kaplansky-type theorem, Mori-Nagata theorem, Nagata rings, and Noetherian property.

• Kyungpook Mathematical Journal
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• 제63권4호
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• pp.577-591
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• 2023

In this paper we establish the L^p boundedness of Marcinkiewicz integral operators on product domains with rough kernels satisfying a weak size condition. We assume that our kernels are supported on surfaces generated by curves more general than polynomials and convex functions. This generalizes and extends previous results.

• 대한수학회논문집
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• 제38권2호
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• pp.401-430
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• 2023

In this paper, we prove L^p estimates of a class of singular integral operators on product domains along surfaces defined by mappings that are more general than polynomials and convex functions. We assume that the kernels are in L(log L)² (𝕊^n-1 × 𝕊^m-1). Furthermore, we prove L^p estimates of the related class of Marcinkiewicz integral operators. Our results extend as well as improve previously known results.

• The Journal of Korean Physical Therapy
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• 제24권4호
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• pp.282-289
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• 2012

Purpose: The purpose of this study is to analyze the home-stay disability's activity, as well as the participation domains and the environment factor domains of international classification of functioning (ICF), in order to examine the effect of the home visiting physical therapy and the disability's activity. Methods: A total of 211 home-stay disabled subjects with brain lesions or crippled disorder, living in 5 cities and districts of Jeollanam-do, underwent 90 minutes of home visiting physical therapy per week during a 6-month period, and using the ICF checklist, evaluated the subject's activity and participation domains and environmental factor domains. Results: The performance qualifier showed a significant statistical change in the movement, self-care, domestic life, interpersonal interactions and relationships, community, society and civic life domains (p<0.05); and the capacity qualifier showed a significant change only in the mobility domains in the before and after of the home visiting physical therapy (p<0.05). The barrier factor in the order of services, systems and policies domains, product and technology domains, and attitude domains it influenced significantly in the performance (p<0.05), and in the facilitator factor in the order of product and technology domains, support and relationships domains, services, systems and policies domains it influenced significantly in the performance of the disabled (p<0.05). Conclusion: The visiting physical therapy can help in the improvement of the activity and participation of the home-stay disabled subjects, and for the accurate evaluation of the home-stay disabled subjects, it is considered that an evaluation including various environmental factors, such as ICF, must be fulfilled.

• 대한수학회보
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• 제55권3호
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• pp.809-818
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• 2018

We study those integral domains in which every proper ideal can be written as an invertible ideal multiplied by a nonempty product of proper radical ideals.

• 한국전자거래학회지
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• 제11권3호
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• pp.53-71
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• 2006

오늘날의 제품개발환경은 다양한 역량을 가진 참여자들의 가상조직 구성을 통한 협업을 요구하고 있으며, 참여자들 사이의 협업은 제품 개발 관련 정보들의 교환을 바탕으로 이루어진다. 제품정보의 효율적인 교환을 지원하기 위하여 본 논문에서는 제품정보에 대한 시맨틱스를 기반으로 가상조직 내 모든 애플리케이션 도메인들이 서로의 제품정보모델을 이해하고 이를 바탕으로 제품정보모델 사이의 상호운용성을 확보할 수 있도록 참조 온톨로지인 Reference Domain Ontology(RDO)를 제안하고 이를 이용한 방법론을 제시한다. RDO는 가상조직에 참여하는 모든 애플리케이션 도메인의 제품정보모델과 메타모델에 대한 시맨틱스를 포함함으로써 협업에서 발생 가능한 제품정보모델 교환의 지연요소를 제거한다. RDO는 가상조직이 형성될 때 생성되며 가상조직의 변화에 능동적으로 대응하고 가상조직이 소멸되면 함께 사라지는 등 민첩하고 일시적인 특성을 지닌다. 이를 위하여 RDO는 상위 온톨로지를 이용한 top-down과 가상 조직 내 애플리케이션 도메인 온톨로지의 병합을 기반으로 하는 bottom-up의 복합적 접근법으로 구축된다.

• 대한수학회보
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• 제58권4호
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• pp.1003-1019
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• 2021

In this paper, we introduce a class of maximal functions along twisted surfaces in ℝⁿ×ℝ^m of the form {(𝜙(|v|)u, 𝜑(|u|)v) : (u, v) ∈ ℝⁿ×ℝ^m}. We prove L^p bounds when the kernels lie in the space L^q (𝕊^n-1×𝕊^m-1). As a consequence, we establish the L^p boundedness for such class of operators provided that the kernels are in L log L(𝕊^n-1×𝕊^m-1) or in the Block spaces B^0,0_q (𝕊^n-1×𝕊^m-1) (q > 1).

• 대한수학회논문집
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• 제33권2호
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• pp.409-421
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• 2018

Let X be a complex manifold of dimension n $n{\geqslant}2$ and let ${\Omega}{\Subset}X$ be a weakly q-convex domain with smooth boundary. Assume that E is a holomorphic line bundle over X and $E^{{\otimes}m}$ is the m-times tensor product of E for positive integer m. If there exists a strongly plurisubharmonic function on a neighborhood of $b{\Omega}$, then we solve the ${\bar{\partial}}$-problem with support condition in ${\Omega}$ for forms of type (r, s), $s{\geqslant}q$ with values in $E^{{\otimes}m}$. Moreover, the solvability of the ${\bar{\partial}}_b$-problem on boundaries of weakly q-convex domains with smooth boundary in $K{\ddot{a}}hler$ manifolds are given. Furthermore, we shall establish an extension theorem for the ${\bar{\partial}}_b$-closed forms.

• 한국CDE학회논문집
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• 제11권1호
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• pp.57-66
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• 2006

Modeling product configurations needs large amounts of knowledge about technical and marketing restrictions on the product. Previous attempts to automate product configurations concentrate on representations and management of the knowledge for specific domains in fixed and isolated computing environments. Since the knowledge about product configurations is subject to continuous change and hard to express, these attempts often failed to efficiently manage and exchange the knowledge in collaborative product development. In this paper, XML Topic Map (XTM) is introduced to represent and exchange the knowledge about product configurations in collaborative product development. A product configuration model based on XTM along with its merger and inference facilities enables configuration engineers In collaborative product development to manage and exchange their knowledge efficiently. An implementation of the proposed product configuration model is presented to demonstrate that the proposed approach enables enterprises to exchange the knowledge about product configurations during their collaborative product development.

• 품질경영학회지
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• 제35권4호
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• pp.101-110
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• 2007

This study developed a new model for evaluating activities related to PL(Product Liability), with which our domestic enterprises can more easily assess the actual status of the management of PL than as they could do before. In addition, this model was designed to make the evaluation can be done focusing on the Product safety management cycle, unlike the other PL evaluation models. This model consists of 3 evaluation domains such as evaluations of planning, implementation, and assessment and taking action regarding product safety management. In order to verify that this evaluation model meets its objectives, the researcher directly conducted evaluations of activities related to PL in 3 companies specializing in electric home appliances through visiting them.