• Nuclear Engineering and Technology
• /
• v.54 no.3
• /
• pp.811-816
• /
• 2022

This work presents the methodology used to expand the capabilities of the Monte Carlo code OpenMC for the calculation of reactor kinetic parameters: effective delayed neutron fraction β_eff and neutron generation time L. The modified code, OpenMC(Time-Dependent) or OpenMC(TD), was then used to calculate the effective delayed neutron fraction by using the prompt method, while the neutron generation time was estimated using the pulsed method, fitting Λ to the decay of the neutron population. OpenMC(TD) is intended to serve as an alternative for the estimation of kinetic parameters when licensed codes are not available. The results obtained are compared to experimental data and MCNP calculated values for 18 benchmark configurations.

• Nuclear Engineering and Technology
• /
• v.55 no.5
• /
• pp.1593-1603
• /
• 2023

In deterministic and Monte Carlo transport codes, b-delayed emission is included using a group structure where all of the precursors are grouped together in 6 groups or families, but given the increase in computational power, nowadays there is no reason to keep this structure. Furthermore, there have been recent efforts to compile and evaluate all the available b-delayed neutron emission data and to measure new and improved data on individual precursors. In order to be able to perform a transient Monte Carlo simulation, data from individual precursors needs to be implemented in a transport code. This work is the first step towards the development of a tool to explore the effect of individual precursors in a fissile system. In concrete, individual precursor data is included by expanding the capabilities of the open source Monte Carlo code OpenMC. In the modified code - named Time Dependent OpenMC or OpenMC(TD)- time dependency related to β-delayed neutron emission was handled by using forced decay of precursors and combing of the particle population. The data for continuous energy neutron cross-sections was taken from JEFF-3.1.1 library. Regarding the data needed to include the individual precursors, cumulative yields were taken from JEFF-3.1.1 and delayed neutron emission probabilities and delayed neutron spectra were taken from ENDF-B/VIII.0. OpenMC(TD) was tested in a monoenergetic system, an energy dependent unmoderated system where the precursors were taken individually or in a group structure, and in a light-water moderated energy dependent system, using 6-groups, 50 and 40 individual precursors. Neutron flux as a function of time was obtained for each of the systems studied. These results show the potential of OpenMC(TD) as a tool to study the impact of individual precursor data on fissile systems, thus motivating further research to simulate more complex fissile systems.

• Knowledge Management Research
• /
• v.11 no.4
• /
• pp.21-39
• /
• 2010

Recommender system is a core component of e-commerce. Correspondingly, metrics to evaluate the system performance have been developed and applied. However, even though we have lots of applications that have tried to adopt recommender systems, the dearth of successfully installed recommender systems for more than a decade leads us to a skeptical thinking that current metrics do not sufficiently indicate the recommender system success in business viability point of view. Hence, the purpose of this paper is to reconfigure measures for recommender system success. Adopting DeLone and McLean's amended model of information system success as the underlying framework, content analysis with intellectual properties on recommender systems was conducted to modify the currently used metrics. Then a model of recommender system success is proposed based on the newly identified metrics are compared with traditional metrics.

• International Journal of Advanced Culture Technology
• /
• v.7 no.1
• /
• pp.128-132
• /
• 2019

This paper is to explore the success factors of the online public grievance redressal system in the Nepal. It empirically tests the conceptual path model developed by DeLone and McLean which consists of six social perception variables with regard to citizen's intention to use the system. The estimates from 577 respondents support all the 13 hypotheses generated from D&L model. People's attitude and social norms are the two most important factors on the continuous usage of the system. It is suggested that the social factors are as much important as technological aspects when it comes to the e-government implementation. It is also suggested that the government should pay more attention to human factors in upgrading the design and development of e-grievance system in the foreseeable future.

• Bulletin of the Korean Space Science Society
• /
• 2000.10a
• /
• pp.40-40
• /
• 2000

No Abstract, See Full Text

• Journal of Microbiology
• /
• v.44 no.6
• /
• pp.591-599
• /
• 2006

To address the diversity of cyclodextrin-producing P. graminis strains isolated from wheat roots and rhizospheres of maize and sorghum sown in Australia, Brazil, and France, restriction fragment length polymorphism analysis of part of genes encoding RNA polymerase (rpoB-RFLP) and DNA gyrase subunit B (gyrB-RFLP) was used to produce genetic fingerprints. A phylogenetic tree based on rpoB gene sequences was also constructed. The isolates originated from Brazil could be separated from those from Australia and France, when data from the rpoB-based phylogenetic tree or gyrB-RFLP were considered. These analyses also allowed the separation of all P. graminis strains studied here into four clusters; one group formed by the strains GJK201 and $RSA19^T$, second group formed by the strains MC22.02 and MC04.21, third group formed by the strains TOD61, TOD 221, TOD302, and TOD111, and forth group formed by all strains isolated from plants sown in Cerrado soil, Brazil. As this last group was formed by strains isolated from sorghum and maize sown in the same soil (Cerrado) in Brazil, our results suggest that the diversity of these P. graminis strains is more affected by the soil type than the plant from where they have been isolated.

• The Bulletin of The Korean Astronomical Society
• /
• v.25 no.2
• /
• pp.40-40
• /
• 2000

• The Korean Journal of Pain
• /
• v.34 no.2
• /
• pp.139-155
• /
• 2021

The quality of subgroup analyses (SGAs) in chronic non-cancer pain trials is uncertain. The purpose of this study was to address this issue. We conducted a comprehensive search in MEDLINE and EMBASE from January 2012 to September 2018 to identify eligible trials. Two pairs of reviewers assessed the quality of the SGAs and the credibility of subgroup claims using the 10 criteria developed by Sun et al. in 2012. The associations between the quality of the SGAs and the studies' characteristics including risk of bias, funding sources, sample size, and the latest impact factor, were assessed using multivariable logistic regression. Our search retrieved 3,401 articles of which 66 were eligible. The total number of SGAs was 177 of which 52 (29.4%) made a subgroup claim. Of these, only 15 (8.5%) were evaluated as being of high quality. Among the 30 SGAs that claimed subgroup effects using an appropriate method of performing interaction tests, the credibility of only 5 were assessed as high. None of the subgroup claims met all the credibility criteria. No significant association was found between the quality of SGAs and the studies' characteristics. The quality of the SGAs performed in chronic pain trials was poor. To enhance the quality of SGAs, scholars should consider the developed criteria when designing and conducting trials, particularly those which need to be specified a priori.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.46 no.6
• /
• pp.102-111
• /
• 2009

In this paper, we propose a de-interlacing algorithm that combines a motion compensation (MC) method and the vertical-temporal filter with motion compensation (MC V-T filter) according to motion compensation reliability. The MC method represent one of the best ways of improving the resolution of de-interlaced frames, but it may introduce motion compensation artifacts in regions with incorrect motion information. In these regions, the MC V-T filter that is very robust to motion vector errors can be used to correct motion compensation artifacts. The combination between two methods is controlled by the motion compensation reliability that is measured by analyzing the estimated motion vectors and the results of MC. The motion compensation reliability contains information about motion compensation artifacts of MC results and determines the combination weight according to this information. Therefore, the combination rule of the proposed method is more accurate than those of the conventional methods and it enables the proposed method to provide high quality video sequences without producing any visible artifacts. Experimental results with various test sequences show that the proposed algorithm outperforms conventional algorithms in terms of both visual and numerical criteria.

• Cartoon and Animation Studies
• /
• s.49
• /
• pp.87-112
• /
• 2017

Overlap what images are laid on top of each other performs various purposes of artistic expressions. Especially, overlap to describe motion has been placed on lots of art fields analysing and connecting each part of motion. This kind of overlap is called as 'Locomotive overlap' and it is defined as 'Technique for multiplication to arrange simultaneously motions of single object on one screen'. Locomotive overlap was started from fine art and photography, so this static kind of it is classified as 'Static locomotive overlap'. Afterwards, film and animation succeeded static locomotion overlap and realized real dynamic locomotive overlap with moving images, so this dynamic kind of it is classified as 'Dynamic locomotive overlap'. Most of all, by Norman McLaren accomplished its own artistic value and aesthetics in locomotive overlap has been placed in the center of the history of locomotive overlap, so to analyze this work and to research before and after it will confirm context and artistic achievements of locomotive overlap. Nowdays locomotive overlap is extending its technology and dimension more and more on the strength of development of digital technology. Some of works using digital technology show new possibilities of locomotive overlap by reinterpreting original media and concept of . Ultimately, this research for locomotive overlap focusing on the analysis of confirms artistic achievements of locomotive overlap and suggests to contemplate the meaning and new possibilities of it.