• Journal of applied mathematics & informatics
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• v.33 no.1_2
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• pp.101-110
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• 2015

A Total Mean Cordial labeling of a graph G = (V, E) is a function $f:V(G){\rightarrow}\{0,1,2\}$ such that $f(xy)={\Large\lceil}\frac{f(x)+f(y)}{2}{\Large\rceil}$ where $x,y{\in}V(G)$, $xy{\in}E(G)$, and the total number of 0, 1 and 2 are balanced. That is ${\mid}ev_f(i)-ev_f(j){\mid}{\leq}1$, $i,j{\in}\{0,1,2\}$ where $ev_f(x)$ denotes the total number of vertices and edges labeled with x (x = 0, 1, 2). If there is a total mean cordial labeling on a graph G, then we will call G is Total Mean Cordial. Here, We investigate the Total Mean Cordial labeling behaviour of prism, gear, helms.

• Journal of Information Management
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• v.40 no.4
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• pp.151-171
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• 2009

This study is to investigate dissatisfaction behavior of customers who purchase products on the Internet shopping mall and to find customers' dissatisfaction behavior types for effectively responding to that. Managing dissatisfaction behaviors are related to the customer satisfaction. To conduct this study, Call Center data was collected and analysed by qualitative method. The results showed that dissatisfaction of product quality and disappointment have different effects on post--purchase behaviors. Customers who feel more dissatisfaction with product quality showed the aggressive response such as exchange, refund, while customers who feel disappointment are likely to switch the shopping mall or to cancel the order. These results of customers' dissatisfaction behaviors indicate that company has to manage both product quality and the customer's experience dimension.

• Bulletin of the Korean Mathematical Society
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• v.60 no.6
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• pp.1463-1475
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• 2023

In this paper, we introduce a class of rings generalizing unit regular rings and being a subclass of semipotent rings, which is called idempotent unit regular. We call a ring R an idempotent unit regular ring if for all r ∈ R - J(R), there exist a non-zero idempotent e and a unit element u in R such that er = eu, where this condition is left and right symmetric. Thus, we have also that there exist a non-zero idempotent e and a unit u such that ere = eue for all r ∈ R - J(R). Various basic characterizations and properties of this class of rings are proved and it is given the relationships between this class of rings and some well-known classes of rings such as semiperfect, clean, exchange and semipotent. Moreover, we obtain some results about when the endomorphism ring of a module in a class of left R-modules X is idempotent unit regular.

• Research in Mathematical Education
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• v.27 no.2
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• pp.195-210
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• 2024

Researchers and curricula continue to call for proof to serve a central role in learning of mathematics throughout kindergarten to grade 12 and beyond. Despite its prominence and recognition gained during past decades, proof is still a stumbling block for both teachers and students. Research efforts have been made to address issues related to teaching and learning of proof. An area in which such research efforts have been made is analysis of curriculum material (i.e. textbook analysis) with a focus on proof. This study is another research effort in this area of research through investigating the guidance offered in curriculum materials with the following research question: What is the nature (e.g., kinds of content knowledge, pedagogical content knowledge) of guidance is offered for teachers to implement proof tasks in grade 8 geometry textbooks? Results indicate that the guidance offered for proof tasks are concerned more with content knowledge about the content-specific instructional goals than with pedagogical content knowledge which supports teachers in preparing in-class interactions with students to teach proof.

• Journal of the Korean Physical Society
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• v.80
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• pp.117-122
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• 2022

The Belle II detector at the SuperKEKB e⁺e^- collider in Japan is designed for precise measurements of weak interaction parameters and new physics beyond the Standard Model; therefore, it requires very high instantaneous luminosity. To handle such high luminosity, the level-1 trigger system in the Belle II experiment is designed to efficiently trigger events of interest with the highest efficiency. Among many sub-detectors, track reconstruction of charged particles is performed using information collected from the central drift chamber. Therefore, the central drift chamber-based trigger plays a central role in distinguishing specific types of physics based on fast track reconstruction. To improve the longitudinal position resolution of a track vertex and for the fine-tuning of trigger signal timing, the time of the collision, which we call event time, is necessary. We developed an event time finding algorithm using the wire hit time information obtained from the central drift chamber and validated our algorithm through Monte Carlo simulation.

• The Journal of Society for e-Business Studies
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• v.18 no.2
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• pp.257-277
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• 2013

Those studies in the field of Management Information Systems and the Success Model of the DeLone and McLean's Information Systems suggest that some factors related to information systems should be developed and operated to affect the performance of the user's personal and companies through the introduction and use of corporate information systems. The purpose of this study is put on searching for some factors which impact on user satisfaction about the customer information management systems of call center. We did conduct on a survey of 539 people who are working as a call center counseling employees as setting up a structural equation model which reflects previous research on working environment and job satisfaction, and modified DeLone and McLean's information system success model. The results of this study are as follows. First, seven of the eleven hypotheses that three quality of the information systems might be affecting working environment, job satisfaction, user satisfaction were adopted Second, we confirmed that the working environment works as a the partial mediation and the quality of services works as a fully mediation between system/information quality and users' satisfaction. The implications of this study are that it is necessary not only to make a good working environment but also to keep improving it in order to boost the operational performance of information systems in the future.

• Fisheries and Aquatic Sciences
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• v.26 no.6
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• pp.380-392
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• 2023

Groupers (Family Epinephelidae) are commonly caught in data-poor small-scale multi-species fisheries for sale on both export and domestic markets. This study presents data on the species composition and size/life-stage structure of Epinephelus spp. groupers caught by small-scale fishers and sold locally in the Indonesian province of South Sulawesi. Data were collected from fishing ports and local markets at 12 sites representing the three seaways around South Sulawesi (Makassar Strait, Flores Sea, Gulf of Bone). Each specimen (n = 3,398) was photographed alongside an object of known length, and total length (TL) was obtained using the Rapid Scaling on Object (RASIO). Of the 23 species identified, four (Epinephelus areolatus, Epinephelus ongus, Epinephelus quoyanus, and Epinephelus fasciatus) collectively comprised 69% of the catch, while the 13 least abundant species contributed less than 5%. The catch was dominated (67%) by the subadult life-stage, with just under 20% in the adult class. Juveniles dominated the catch of Epinephelus fuscoguttatus, a valuable export commodity. Observations of early maturity as well as the sizeable gap between length at first capture (Lc) and length at first maturity (Lm) indicate recruitment overfishing of most species, with the notable exception of Epinephelus rivulatus. The proportion of adult fish was low (≈5%-30%) for the twelve most abundant species (E. areolatus, E. ongus, Epinephelus quoyanus, E. fasciatus, Epinephelus coioides, Epinephelus faveatus, Epinephelus sexfasciatus, Epinephelus maculatus, Epinephelus bleekeri, Epinephelus corallicola, E. fuscoguttatus, Epinephelus polyphekadion). For two moderately abundant species (E. faveatus and E. malabaricus), TL < Lm for all specimens. The limited data available indicate spawning ratio is lower than reported from deep-water fisheries of E. areolatus and E. coioides. The results call for targeted research to fill knowledge gaps regarding the biology and ecology of groupers exploited mainly for domestic markets; highlight the need for species-level data to inform management policies such as minimum legal size regulations; and can contribute towards species-level status assessments.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.187-191
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• 2000

Sulmonella gyhi is one of important causes of human enteric infections. S @phi I

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.6
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• pp.903-909
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• 2018

In December 2017, the world's first LTE-R for 250km/h high-speed railway was commercialized with the opening of Wonju-Gangneung high-speed railway. LTE-R has many advantages such as voice and video call, high-speed data transmission, coverage redundancy and DU redundancy. But it requires efficient use of radio resources because of a limited bandwidth of 10MHz for UL and DL, respectively. The existing unicast scheme has limited high frequency efficiency so when the number of users increases, service is limited due to the network load, which could be a problem for LTE-R in terms of stability and reliability. On the other hand, the multicast scheme via eMBMS can provide stable service even if the number of video users is high. This paper derives the number of unicast scheme users considering the LTE-R network with LAB test and calculation result, and proposes implementation plans and considerations for eMBMS commercialization on LTE-R.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.33.1-33.1
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• 2016

Dwarf elliptical galaxies (dEs), the most abundant galaxy type in clusters, were recently shown to exhibit a wide variety in their properties. Particularly, the presence of blue cores in some dEs, what we call dE(bc), supports the scenario of late-type galaxy infall and subsequent transformation into red, quiescent dEs. While several transformation mechanisms for these dE(bc)s within cluster environment have been proposed, all these processes are able to explain only some of the observational properties of dEs. In this context, internal kinematic properties of dE(bc)s provide the most crucial evidence to discriminate different processes for the formation of these galaxies. We present Gemini Multi Object Spectrograph (GMOS) long-slit spectroscopy of two dE(bc)s in the Virgo cluster. We obtained radial profiles of velocity and velocity dispersion out to ~1.3 effective radius. We found that two dE(bc)s exhibit kinematically decoupled components as well as distinct peculiar features in velocity profiles, supporting the scenario of mergers. We also found that these galaxies are structurally compatible with low surface brightness component of blue compact dwarf galaxies. We suggest that a part of dE(bc)s in the Virgo Cluster were formed through galaxy merger in low density environment such as galaxy group or outskirt of the cluster, and then were quenched by subsequent effects within cluster environment.