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A SE Approach for Real-Time NPP Response Prediction under CEA Withdrawal Accident Conditions

  • Felix Isuwa, Wapachi;Aya, Diab
    • Journal of the Korean Society of Systems Engineering
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    • v.18 no.2
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    • pp.75-93
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    • 2022
  • Machine learning (ML) data-driven meta-model is proposed as a surrogate model to reduce the excessive computational cost of the physics-based model and facilitate the real-time prediction of a nuclear power plant's transient response. To forecast the transient response three machine learning (ML) meta-models based on recurrent neural networks (RNNs); specifically, Long Short Term Memory (LSTM), Gated Recurrent Unit (GRU), and a sequence combination of Convolutional Neural Network (CNN) and LSTM are developed. The chosen accident scenario is a control element assembly withdrawal at power concurrent with the Loss Of Offsite Power (LOOP). The transient response was obtained using the best estimate thermal hydraulics code, MARS-KS, and cross-validated against the Design and control document (DCD). DAKOTA software is loosely coupled with MARS-KS code via a python interface to perform the Best Estimate Plus Uncertainty Quantification (BEPU) analysis and generate a time series database of the system response to train, test and validate the ML meta-models. Key uncertain parameters identified as required by the CASU methodology were propagated using the non-parametric Monte-Carlo (MC) random propagation and Latin Hypercube Sampling technique until a statistically significant database (181 samples) as required by Wilk's fifth order is achieved with 95% probability and 95% confidence level. The three ML RNN models were built and optimized with the help of the Talos tool and demonstrated excellent performance in forecasting the most probable NPP transient response. This research was guided by the Systems Engineering (SE) approach for the systematic and efficient planning and execution of the research.

Effect of in ovo feeding of γ-aminobutyric acid combined with embryonic thermal manipulation on hatchability, growth, and hepatic gene expression in broilers

  • Chris Major, Ncho;Akshat, Goel;Vaishali, Gupta;Chae-Mi, Jeong;Yang-Ho, Choi
    • Animal Bioscience
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    • v.36 no.2
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    • pp.284-294
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    • 2023
  • Objective: This study investigated the effects of in ovo feeding of γ-aminobutyric acid (GABA) and embryonic thermal manipulation (ETM) on growth performance, organ indices, plasma biochemical parameters, hepatic antioxidant levels, and expression of lipid metabolism-related genes in broilers. Methods: Two hundred and fifty eggs were assigned to one of four treatments: control eggs incubated under standard conditions (CON); eggs that received an in ovo injection of 10% GABA on day 17.5 of incubation (G10); thermally manipulated eggs between days 10 and 18 of incubation at 39.6°C for 6 h daily (TM); and eggs that received both treatments during incubation (G10+TM). After 28 days of rearing, five birds per treatment were selected for blood and organ sampling. Results: No differences were found in hatchability or growth parameters among different treatment groups. Hepatic gene expression of catalase (CAT) and glutathione peroxidase 1 (GPx1) was upregulated (p = 0.046 and p = 0.006, respectively) in the G10+TM group, while that of nuclear factor erythroid 2-related factor 2 (NRF2) was upregulated (p = 0.039) in the G10 group. In addition, the relative gene expression of NADPH oxidase 1 (NOX1) was significantly lower (p = 0.007) in all treatment groups than that in the CON group. Hepatic fatty acid synthase (FAS) levels and average daily feed intake (ADFI) of last week showed a positive correlation (r = 0.50, p = 0.038). In contrast, the relative gene expression of the extracellular fatty acid-binding protein (EXFAB) and peroxisome proliferator-activated receptor-γ (PPAR-γ) were positively correlated (r = 0.48, p = 0.042 and r = 0.50, p = 0.031) with the overall ADFI of birds. Conclusion: Taken together, the results of this study suggest that the combination of in ovo feeding of GABA and ETM can enhance hepatic antioxidant function in broilers.

Study on Digitalisation of the Tourism Industry in the Regions of the Russian Federation

  • Ivanova, Raisa;Skrobotova, Olga;Polyakova, Irina;Karaseva, Galina;Strelnikova, Marina
    • International Journal of Computer Science & Network Security
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    • v.22 no.8
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    • pp.385-391
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    • 2022
  • The relevance of the published study lies in the fact that since the introduction of the first Global Distribution System, new information and communication technologies have constantly been changing the tourism industry. In the context of a current digital environment, travel agencies can't avoid participating in digital transformation processes aimed at rethinking operational models, skills, and organisational structures in the regions. This publication aims to present and provide a critical overview of digitalisation processes in tourism development in the regions of the Russian Federation, as well as to reflect on the challenges to the widespread digitalisation processes in the regional tourism sector. The subject of research is digitalisation processes, as they radically transform the modern tourism industry, in the regions as well. The pragmatic research paradigm was considered the most appropriate for the study of tourism digitalisation processes in the regions, as it does not require the selection of a specific theoretical basis for data collection. The pragmatic approach forms an alternative to classical theoretical approaches and serves as a particular type of grounded theory, combining both inductive and deductive methods. No software was used for the inductive part of the analysis. The deductive part was conducted using the qualitative data analysis software Nvivo 11. Given the wide diversity of interested parties in the regional tourism digital area, a stratified purposive sampling method was preferred due to its ability to adequately represent the full picture of the phenomenon under study. The selection and stratum criteria were chosen to maximise the representation of different perspectives in the regional tourism digital area. The novelty of the study is due to the digitalisation processes, with an implication of new needs, while opening up promising opportunities for more productive tourism business in the regions of the Russian Federation. Currently, e-tourism in the Russian Federation has become a subject of lively debate among scholars and practitioners. However, the involvement of advanced digitalisation technologies in the field of information processes in the regions of the Russian Federation is of a very sporadic character.

Population structure and regeneration of Zanthoxylum armatum DC. in Salyan, Nepal

  • Phuyal, Nirmala;Jha, Pramod Kumar;Raturi, Pankaj Prasad;Rajbhandary, Sangeeta
    • Journal of Ecology and Environment
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    • v.46 no.2
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    • pp.111-125
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    • 2022
  • Background: Zanthoxylum armatum is one of the 30 prioritized medicinal plants for economic development of Nepal with a high trade value. Understanding the ecology of individual species is important for conservation and cultivation purposes. However, relation of ecological factors on the distribution and populations of Z. armatum in Nepal remain unknown. To address this knowledge gap, an attempt has been made to study the population structure, distribution, and regeneration potentiality of Z. armatum. Vegetation sampling was conducted at six different localities of Salyan district along the elevation range of 1,000 m to 2,000 m. Results: Altogether 50 plant species belonging to 44 genera under 34 families were found to be associated with Z. armatum. Significantly higher species richness was found at Rim (1,400-1,700 m) and Chhatreshwori (1,800-2,000 m) and lower at Kupinde (1,600-1,800 m). The highest population density of Z. armatum was at Kupinde (1,600-1,800 m) with a total of 1,100 individuals/ha. and the lowest at Chhatreshwori (1,800-2,000 m) with 740 individuals/ha. Based on the A/F value (Whitford index), it can be said that Z. armatum has random distribution in the study area. The plants were categorized into seedlings, saplings and adults based on plant height and the status of natural regeneration category determined. The regeneration potentiality of Z. armatum in the study area was fair with the average seedlings and saplings densities of 150 and 100 individuals/ha. Respectively. A Shannon-Weinner index mean value of 2.8 was obtained suggesting high species diversity in the study area. Conclusions: The natural distribution and regeneration of Z. armatum is being affected in the recent years due to anthropogenic disturbances. Increasing market demand and unsustainable harvesting procedures are posing serious threat to Z. armatum. Thus, effective conservation and management initiatives are most important for conserving the natural population of Z. armatum in the study area.

Estimation on Altitudinal Spectrum of Suitability for Four Species of the Mayfly Genus Ephemera (Ephemeroptera: Ephemeridae) Using Probability Distribution Models (확률분포모형을 이용한 하루살이속(Ephemera) 4종의 고도구배에 따른 서식처적합도 평가)

  • Dongsoo Kong;Bomi Kang
    • Journal of Korean Society on Water Environment
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    • v.39 no.4
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    • pp.302-315
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    • 2023
  • Distribution characteristics and altitudinal gradient of four species (E. strigata, E. separigata, E. orientalis-sachalinensis group) of the mayfly genus Ephemera (Order Ephemeroptera) were analyzed with probability distribution models (exponential, normal, lognormal, logistic, Weibull, gamma, beta, Gumbel). Data was collected from 23,846 sampling units of 6,787 sites in Korea from 2010 to 2021. The beta distribution model showed the best fit for positively skewed E. orientalis-sachalinensis and little-skewed E. strigata along with altitudinal gradient. The reversed lognormal distribution model showed the best-fit for negatively skewed E. separigata. E. orientalis-sachalinensis distributed at the range of altitude 1~700 m (mean 251 m, median 226 m, mode 124 m, and standard deviation 161 m), E. strigata distributed at the range of altitude 5~871 m (mean 474 m, median 478 m, mode 492 m, and standard deviation 200 m), E. separigata distributed at the range of altitude 7~846 m (mean 620 m, median 659 m, mode 760 m, and standard deviation 181 m). Altitudinal habitat suitability ranges were estimated to be 42~257 m for E. orientalis-sachalinensis, 335~644 m for E. strigata, and 641~824 m for E. separigata. Based on the altitudinal spectrum of suitability and altitude-related temperature analysis results, E. orientalis-sachalinensis was estimated to be thermophilic, E. strigata to be mesophilic, and E. separigata to be thermophobic. This is the first national-scale evaluation of the altitudinal distribution of Ephemera in Korea. These results will be used in a further research study on altitudinal shift of the species of Ephemera under climate change.

Constructing a Conceptual Electronic Record Management System Model Based on Eight Indonesian Education Standards to Support School Accountability

  • Nina Oktarina;Murwatiningsih;Hana Netti Purasani;Ahmad Sehabuddin;Edy Suryanto
    • Journal of Information Science Theory and Practice
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    • v.11 no.3
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    • pp.16-28
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    • 2023
  • Record management, especially in schools as an institution's information centre, needs serious attention from government agencies. Under record management policy, there needs to be practical guidance on record management specific to schools. This paper aims to construct a record management model based on the Eight Indonesian Education Standards to support school accountability in Indonesia. The urgency of this paper in filling the gap in the Electronic Record Management System (ERMS) role is primarily to support school accountability. It is important to include educational laws and regulations in Indonesia to be a foundation in archive management, including preparing the ERMS. This study aims to develop a model of record management in schools. The final stage in this research is to find the final model. The final model is a model that experts and practitioners have validated. A total of 30 records managers were selected for the interviews. Furthermore, the trial was carried out in 30 senior high schools. The research sampling consisted of representatives of archive managers at selected schools from five islands in Indonesia (Kalimantan, Java, Papua, Sumatra, and Sulawesi). Our research findings show that conceptual models meet valid criteria and significantly impact archivist performance in better schools. The practical implication is that the archival management model based on national education standards policies contributes to practical archives and records management to support school accountability.

Plant co-occurrence patterns and soil environments associated with three dominant plants in the Arctic

  • Deokjoo Son
    • Journal of Ecology and Environment
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    • v.47 no.1
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    • pp.1-13
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    • 2023
  • Background: The positive effects of Arctic plants on the soil environment and plant-species co-occurrence patterns are known to be particularly important in physically harsh environments. Although three dominant plants (Cassiope tetragona, Dryas octopetala, and Silene acaulis) are abundant in the Arctic ecosystem at Ny-Ålesund, Svalbard, few studies have examined their occurrence patterns with other species and their buffering effect on soil-temperature and soil-moisture fluctuation. To quantify the plant-species co-occurrence patterns and their positive effects on soil environments, I surveyed the vegetation cover, analyzed the soil-chemical properties (total carbon, total nitrogen, pH, and soil organic matter) from 101 open plots, and measured the daily soil-temperature and soil-moisture content under three dominant plant patches and bare soil. Results: The Cassiope tetragona and Dryas octopetala communities increased the soil-temperature stability; however, the three dominant plant communities did not significantly affect the soil-moisture stability. Non-metric multidimensional scaling separated the sampling sites into three groups based on the different vegetation compositions. The three dominant plants occurred randomly with other species; however, the vegetation composition of two positive co-occurring species pairs (Oxyria digyna-Cerastium acrticum and Luzula confusa-Salix polaris) was examined. The plant species richness did not significantly differ in the three plant communities. Conclusions: The three plant communities showed distinctive vegetation compositions; however, the three dominant plants were randomly and widely distributed throughout the study sites. Although the facilitative effects of the three Arctic plants on increases in the soil-moisture fluctuation and richness were not quantified, this research enables a deeper understanding of plant co-occurrence patterns in Arctic ecosystems and thereby contributes to predicting the shift in vegetation composition and coexistence in response to climate warming. This research highlights the need to better understand plant-plant interactions within tundra communities.

Spatio-Temporal Variation of Soil Respiration and Its Association with Environmental Factors in Bluepine Forest of Western Bhutan

  • Cheten Thinley;Baghat Suberi;Rekha Chhetri
    • Journal of Forest and Environmental Science
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    • v.39 no.1
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    • pp.13-19
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    • 2023
  • We investigated Soil respiration in Bluepine forest of western Bhutan, in relation to soil temperature, moisture content and soil pH and it was aimed at establishing variability in space and time. The Bluepine forest thrives in the typical shallow dry valleys in the inter-montane Bhutan Himalaya, which is formed by ascending wind from the valley bottom, which carries moisture from the river away to the mountain ridges. Stratified random sampling was applied and the study site was classified into top, mid, low slope and further randomized sample of n=20 from 30 m×30 m from each altitude. The overall soil respiration mean for the forest was found 2248.17 CO2 g yr-1 and it is ~613.58 C g yr-1. The RS from three sites showed a marginal variation amongst sites, lower slope (2,309 m) was 4.64 μ mol m-2 s-1, mid slope (2,631 m) was 6.78 μ mol m-2 s-1 and top slope (3,027 m) was 6.33 μ mol m-2 s-1 and mean of 5.92 μ mol m-2 s-1, SE=0.25 for the forest. Temporal distribution and variations were observed more pronounced than in the space variation. Soil respiration was found highest during March and lowest in September. Soil temperature had almost inverse trend against soil respiration and dropped a low in February and peak in July. The moisture in the soil changed across months with precipitation and pH remained almost consistent across the period. The soil respiration and soil temperature had significant relationship R2=-0.61, p=0.027 and other variables were found insignificant. Similar relationship are reported for dry season in a tropical forest soil respiration. Soil temperature was found to have most pronounced effect on the soil respiration of the forest under study.

A Study of Arctic Microbial Community Structure Response to Increased Temperature and Precipitation by Phospholipid Fatty Acid Analysis

  • Sungjin Nam;Ji Young Jung
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.4 no.2
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    • pp.86-94
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    • 2023
  • Climate change is more rapid in the Arctic than elsewhere in the world, and increased precipitation and warming are expected cause changes in biogeochemical processes due to altered microbial communities and activities. It is crucial to investigate microbial responses to climate change to understand changes in carbon and nitrogen dynamics. We investigated the effects of increased temperature and precipitation on microbial biomass and community structure in dry tundra using two depths of soil samples (organic and mineral layers) under four treatments (control, warming, increased precipitation, and warming with increased precipitation) during the growing season (June-September) in Cambridge Bay, Canada (69°N, 105°W). A phospholipid fatty acid (PLFA) analysis method was applied to detect active microorganisms and distinguish major functional groups (e.g., fungi and bacteria) with different roles in organic matter decomposition. The soil layers featured different biomass and community structure; ratios of fungal/bacterial and gram-positive/-negative bacteria were higher in the mineral layer, possibly connected to low substrate quality. Increased temperature and precipitation had no effect in either layer, possibly due to the relatively short treatment period (seven years) or the ecosystem type. Mostly, sampling times did not affect PLFAs in the organic layer, but June mineral soil samples showed higher contents of total PLFAs and PLFA biomarkers for bacteria and fungi than those in other months. Despite the lack of response found in this investigation, long-term monitoring of these communities should be maintained because of the slow response times of vegetation and other parameters in high-Arctic ecosystems.

A Study on Reappeared Consolidation Test of In-situ Property and Vertical Deformation of Sample Due to Stress Release (1차원 압밀점토의 응력해방에 의한 수직변형량과 현장재현 압밀시험에 관한 연구)

  • Kim, Jae-Young;Naotoshi, Takada
    • Journal of the Korean Geotechnical Society
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    • v.24 no.7
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    • pp.75-80
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    • 2008
  • When a saturated clay is sampled in an undisturbed manner from a bore hole, the sample extends vertically and shrinks horizontally under undrained conditions due to stress release. The conventional consolidation test specimen is trimmed from the expanded sample so that its diameter is equal to the inner diameter of the consolidation test ring, and this test procedure does not reproduce the actual consolidation behavior. The measurement of sample extension was conducted by means of overcoring method showed that the extension strains were 1 to 2%. To simulate the in-situ consolidation behavior, we proposed the consolidation test method that uses a specimen with a slightly smaller diameter than the inside diameter of consolidometer so that the specimen expands laterally to the inside of the ring.