• Kyungpook Mathematical Journal
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• 제49권2호
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• pp.221-233
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• 2009

In this article, we generalize a well-known result of Hebisch and Weinert that states that a finite semidomain is either zerosumfree or a ring. Specifically, we show that the class of commutative semirings S such that S has nonzero characteristic and every zero-divisor of S is nilpotent can be partitioned into zerosumfree semirings and rings. In addition, we demonstrate that if S is a finite commutative semiring such that the set of zero-divisors of S forms a subtractive ideal of S, then either every zero-sum of S is nilpotent or S must be a ring. An example is given to establish the existence of semirings in this latter category with both nontrivial zero-sums and zero-divisors that are not nilpotent.

• 한국수학교육학회지시리즈A:수학교육
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• 제46권4호
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• pp.357-369
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• 2007

Teachers and students' knowledge of zero was investigated through data collected from 16 preservice secondary mathematics teachers and 20 gifted secondary school students. Results showed that these teachers and students had an inadequate knowledge about zero. They exhibited a reluctance to accept zero as an attribute for classification, confusion as to whether or not zero is a number, and stable patterns of computational error. Although leachers and researchers have long recognized the value of analyzing student errors for diagnosis and remediation, students have not been encouraged to take advantage of errors as learning opportunities in mathematics instruction. The article suggests using errors as springboards for inquiry in action, discusses its potential contributions to mathematics instruction by analyzing students and preservice teachers errors related to zero.

• Journal of applied mathematics & informatics
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• 제41권2호
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• pp.247-263
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• 2023

In this article, we investigate the uniqueness problem of q-shift difference polynomial of meromorphic (entire) function with zero-order. Consequently, we prove three results with significantly generalize the results of Goutam Haldar.

• 응용통계연구
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• 제28권3호
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• pp.583-592
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• 2015

영-과잉(zero-inflation) 현상은 최근 계수(count) 시계열 분석의 주요토픽으로 다루어지고 있다. 본 논문에서는 영-과잉 계수 시계열의 변동성을 연구하고 있다. 기존의 정수형 모형인 INGARCH(integer valued GRACH) 모형에 조건부 포아송 및 조건부 음이항 분포를 사용하여 변동성에 영-과잉 현상을 추가하였다. 모수 추정 방법으로 EM알고리즘을 사용하였으며 국내 콜레라 발생건수에 적용시켜 보았다.

• Safety and Health at Work
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• 제13권3호
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• pp.372-375
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• 2022

In the globalized field of safety, health, and well-being, the need to build multi-stakeholder alliances to find solutions to complex challenges is growing. This requires common ground for collaboration, as well as concepts and tools to grasp and manage the areas of interest. Over recent years, Vision Zero has awakened interest and it continues to evolve into many forms of approaches and initiatives, which provide a strategic direction and practical tools for supporting the development of safety, health, and well-being at work. Consequently, there is a need to build a shared understanding of 'zero'. This article reflects the potential of Vision Zero as a bridging concept and an approach for building multi-stakeholder collaboration. Thus, we present a multi-perspective framework of Vision Zero to support further dialoge and collaboration in joint undertakings.

• ETRI Journal
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• 제46권4호
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• pp.619-632
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• 2024

Medical signal processing requires noise and interference-free inputs for precise segregation and classification operations. However, sensing and transmitting wireless media/devices generate noise that results in signal tampering in feature extractions. To address these issues, this article introduces a finite impulse response design based on a two-level transpose Vedic multiplier. The proposed architecture identifies the zero-noise impulse across the varying sensing intervals. In this process, the first level is the process of transpose array operations with equalization implemented to achieve zero noise at any sensed interval. This transpose occurs between successive array representations of the input with continuity. If the continuity is unavailable, then the noise interruption is considerable and results in signal tampering. The second level of the Vedic multiplier is to optimize the transpose speed for zero-noise segregation. This is performed independently for the zero- and nonzero-noise intervals. Finally, the finite impulse response is estimated as the sum of zero- and nonzero-noise inputs at any finite classification.

• 자동차안전학회지
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• 제15권2호
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• pp.35-41
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• 2023

On December 19, 2015, as Article 29-3 (Installation of Accident Recording Devices and Provision of Information) of Motor Vehicle Management Act came into force, In Korea, the EDR (Event Data Recorder) reports are often used for the analysis of various traffic accident cases such as multiple collisions, traffic insurance crimes, and sudden unintended acceleration (SUA), and the others. So many investigators have analyzed the driver's behavior and vehicle situation by comparing the time zero in the EDR report to the actual crash time in dash-cam (or CCTV). Time zero (T0) is defined as the reference time for the record interval or time interval when recording an accident in Article 56-2, Enforcement rule of Performance and Standard for Automobile and Automotive parts. Also in the EDR report, time zero (T0) is defined as whichever of the following occurs first; 1. "wake-up" by an air-bag control system, 2. Continuously running algorithms (by monitoring of longitudinal or lateral delta-V), 3. Deployment of a non-reversible deployment restraint. We have already proposed the "Flowchart & Checklist" to adopt the EDR report for traffic accident investigation and the necessity of specialized institutions or courses to systematically educate or analyze the EDR data. Therefore, in this paper, we report to traffic accident investigators notable points and analysis methods based on some real-world traffic accidents that can be misjudged in specifying time zero (T0).

• Journal of Power Electronics
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• 제17권4호
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• pp.860-873
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• 2017

The present article reports an analysis and investigation of a direct AC-AC quasi-resonant converter. A bidirectional power device, whose switching frequency is lower than the frequency of the current passing through the load, is used for its realization. The zero voltage switching mode is described when zero voltage on the power device is available by measuring it with the control system. The continuous current in the resonant inductance by switching the power device at zero voltage is considered, and it is characterized by two sub-modes. A mathematical analysis of the processes has been made and comparative results from the computer simulation and experimental study have been brought. The converter can be used in a wide areas of power electronics: induction heating, wireless power transfer, AC-DC converters, etc.

• 대한수학회지
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• 제53권3호
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• pp.519-532
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• 2016

The zero-divisor graph of a noncommutative ring R, denoted by ${\Gamma}(R)$, is a graph whose vertices are nonzero zero-divisors of R, and there is a directed edge from a vertex x to a distinct vertex y if and only if xy = 0. Let $R=M_2(F_q)$ be the $2{\times}2$ matrix ring over a finite field $F_q$. In this article, we investigate the automorphism group of ${\Gamma}(R)$.

• Journal of applied mathematics & informatics
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• 제40권3_4호
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• pp.729-740
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• 2022

Let ℤ be the ring of integers and let ℤ_n be the ring of integers modulo n. Let ℤ(+)ℤ_n be the idealization of ℤ_n in ℤ and let (ℤ(+)ℤ_n)[X]] be either (ℤ(+)ℤ_n)[X] or (ℤ(+)ℤ_n)[[X]]. In this article, we study the zero-divisor graphs of ℤ(+)ℤ_n and (ℤ(+)ℤ_n)[X]]. More precisely, we completely characterize the diameter and the girth of the zero-divisor graphs of ℤ(+)ℤ_n and (ℤ(+)ℤ_n)[X]]. We also calculate the chromatic number of the zero-divisor graphs of ℤ(+)ℤ_n and (ℤ(+)ℤ_n)[X]].