• Journal of Power Electronics
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• 제19권5호
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• pp.1248-1258
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• 2019

This paper presents a moth-flame optimization (MFO)-based maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The MFO algorithm is a new optimization method that exhibits satisfactory performance in terms of exploration, exploitation, local optima avoidance, and convergence. Therefore, the MFO algorithm is quite suitable for solving multiple peaks of PV systems under partial shading conditions (PSCs). The proposed MFO-MPPT is compared with four MPPT algorithms, namely the perturb and observe (P&O)-MPPT, incremental conductance (INC)-MPPT, particle swarm optimization (PSO)-MPPT and whale optimization algorithm (WOA)-MPPT. Simulation and experiment results demonstrate that the proposed algorithm can extract the global maximum power point (MPP) with greater tracking speed and accuracy under various conditions.

• Korean Journal of Radiology
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• 제25권1호
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• pp.86-102
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• 2024

Early diagnosis, accurate assessment, and localization of peritoneal metastasis (PM) are essential for the selection of appropriate treatments and surgical guidance. However, available imaging modalities (computed tomography [CT], conventional magnetic resonance imaging [MRI], and 18fluorodeoxyglucose positron emission tomography [PET]/CT) have limitations. The advent of new imaging techniques and novel molecular imaging agents have revealed molecular processes in the tumor microenvironment as an application for the early diagnosis and assessment of PM as well as real-time guided surgical resection, which has changed clinical management. In contrast to clinical imaging, which is purely qualitative and subjective for interpreting macroscopic structures, radiomics and artificial intelligence (AI) capitalize on high-dimensional numerical data from images that may reflect tumor pathophysiology. A predictive model can be used to predict the occurrence, recurrence, and prognosis of PM, thereby avoiding unnecessary exploratory surgeries. This review summarizes the role and status of different imaging techniques, especially new imaging strategies such as spectral photon-counting CT, fibroblast activation protein inhibitor (FAPI) PET/CT, near-infrared fluorescence imaging, and PET/MRI, for early diagnosis, assessment of surgical indications, and recurrence monitoring in patients with PM. The clinical applications, limitations, and solutions for fluorescence imaging, radiomics, and AI are also discussed.

• Geomechanics and Engineering
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• 제36권6호
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• pp.631-640
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• 2024

In the traditional slope stability analysis, ignoring the spatial variability of slope soil will lead to inaccurate analysis. In this paper, the K-L series expansion method is adopted to simulate random field of soil strength parameters. Based on Random Limit Equilibrium Method (RLEM), the influence of variation coefficient and fluctuation range on reliability of soil slope supported by micro-pile is investigated. The results show that the fluctuation ranges and the variation coefficients significantly influence the failure probability of soil slope supported by micro-pile. With the increase of fluctuation range of soil strength parameters, the mean safety factor of the slope increases slightly. The failure probability of the soil slope increases with the increase of fluctuation range when the mean safety factor of the slope is greater than 1. The failure probability of the slope increases by nearly 8.5% when the fluctuation range is increased from δ_v=2 m to δ_v =8 m. With the increase of the variation coefficient of soil strength parameters, the mean safety factor of the slope decreases slightly, and the probability of failure of soil slope increases accordingly. The failure probability of the slope increases by nearly 31% when the variation coefficient increases from COV_c=0.2, COV_φ=0.05 to COV_c=0.5, COV_φ=0.2.

• Journal of Power Electronics
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• 제17권2호
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• pp.476-489
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• 2017

Under partial shading conditions (PSCs), multiple maximums may be exhibited on the P-U curve of string inverter photovoltaic (PV) systems. Under such conditions, heuristic methods are invalid for extracting a global maximum power point (GMPP); intelligent algorithms are time-consuming; and model-based methods are complex and costly. To overcome these shortcomings, a novel hybrid MPPT (MPF-IP&O) based on a model-based peak forecasting (MPF) method and an improved perturbation and observation (IP&O) method is proposed. The MPF considers the influence of temperature and does not require solar radiation measurements. In addition, it can forecast all of the peak values of the PV string without complex computation under PSCs, and it can determine the candidate GMPP after a comparison. Hence, the MPF narrows the searching range tremendously and accelerates the convergence to the GMPP. Additionally, the IP&O with a successive approximation strategy searches for the real GMPP in the neighborhood of the candidate one, which can significantly enhance the tracking efficiency. Finally, simulation and experiment results show that the proposed method has a higher tracking speed and accuracy than the perturbation and observation (P&O) and particle swarm optimization (PSO) methods under PSCs.

• Proceedings of the KSCN Conference
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• 대한지역사회영양학회 2005년도 10th Anniversary International Symposium
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• pp.20-32
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• 2005

With the prosperous economy, the status of diet and nutrition among the urban and rural Chinese population has been improved significantly. This paper will focuses on three main surveys in China. (1)'Food and Nutrition Surveillance System in China': Phase I focused on analysis of previous data. Phase II was a pilot survey initiated in Beijing, Hebei, Heilongjiang, Ningxia, Zhejiang, Guangzhou, and Sichuan in 1990. (2) 'The China Health and Nutrition Survey' is an ongoing longitudinal project covered 8(9) provinces in 1991,1993,1997,2000. This paper will analysis the adults aged 18 45 of 1991, 1993, 1997, and 2000. (3) Survey on the status of nutrition and health of the Chinese (2002) is an across sectional study covered 31 provinces, autonomous region and the municipalities. The data was used to analyze the status of food consumption and dietary nutrients intake of Chinese population. In the past ten years, the prevalence of malnutrition and nutrition deficiency has been continuously decreased. The consumptions of animal products, milk, and edible oil have been increased, while the dairy and legume products consumption decreased. The unbalance was showed with a downward trend in cereals, vegetables and fruits consumption and a significant increase in animal products and oil intake among urban people. Dietary pattern of some subjects went away to 'high energy density' diet. The deficiency of calcium, retinal and ascorbic acid etc, especially in the rural areas still exist. China is undergoing a remarkable, but undesirable, rapid transition towards a stage of the nutrition transition characterized by high rates of DR NCDs in a very short time. China is facing the dual challenges of nutrition deficiency and nutrition imbalance. The results can help to understand the dietary structure and the status of nutrition among Chinese people over the past years. It will provide the basis for formulating relevant state policies.

• Journal of Electrical Engineering and Technology
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• 제10권5호
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• pp.1930-1939
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• 2015

Wind power planning aims to locate and size wind farms optimally. Traditionally, wind power planners tend to choose the wind farms with the richest wind resources to maximize the energy benefit. However, the capacity benefit of wind power should also be considered in large-scale clustered wind farm planning because the correlation among the wind farms exerts an obvious influence on the capacity benefit brought about by the combined wind power. This paper proposes a planning model considering both the energy and the capacity benefit of the wind farms. The capacity benefit is evaluated by the wind power capacity credit. The Ordinal Optimization (OO) Theory, capable of handling problems with non-analytical forms, is applied to address the model. To verify the feasibility and advantages of the model, the proposed model is compared with a widely used genetic algorithm (GA) via a modified IEEE RTS-79 system and the real world case of Ningxia, China. The results show that the diversity of the wind farm enhances the capacity credit of wind power.

• Journal of the Korea Convergence Society
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• 제11권11호
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• pp.353-359
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• 2020

The purpose of this study is to analyze the TPACK differences between pre-service and in-service teachers in China, and determine demographic influence variables on the differences between them. The participants of this study were 567 teachers, including 335 pre-service teachers and 232 in-service teachers from Ningxia, China. The results are as follows: First, The in-service teachers in the seven areas of TPACK scored higher than those of pre-service teachers; Second, The comparison of the average difference between teacher division and gender shows that the two factors have an interactive effect on TK. This study is meaningful because it compared the TPACK differences between pre-service and in-service teachers, and found out the effect of gender interaction on the differences in China; It provides practical suggestions for improving the TPACK ability of Chinese teachers. Finally, the discussion was conducted based on the results, and a follow-up study was suggested.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4327-4333
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• 2016

Purpose: To systematically review efficacyand safety of robotic gastrectomy (RG) compared with conventional laparoscopic gastrectomy (LG) for gastric carcinoma. Materials and Methods: A systematic literature search was carried out using PubMed, Cochrane Library, CBM, CNKI, WanFang, VIP and other sources like relevant references to obtain comparative studies assessing the effectiveness and safety between RG and LG published between 2013 and 2016. Then the literature was screened and the data were extracted by 2 independent reviewers. The quality of the literature was assessed, and the data analyzed using Stata/SE 14 software. Fixed effects or random effects models wereapplied according to heterogeneity. Results: A total of 12 non-randomized observational clinical studies involving 3,580 patients were included, of which 1,096 had undergone RG and 2,484 had received LG. The results of the meta-analysis showed in terms of effectiveness, RG was associated with less blood loss, less time to first flatus and greater number of harvested lymph nodes, but there were no significant differences in proximal and distal resection margins, compared with LG. In terms of efficiency, RG was associated with shorter hospital stay, but longer operative time. In terms of safety, there were no statistically significant differences in complications, mortality and conversions between RG and LG. Conclusions: RG can achieve comparable or better short-term and radical effects than LG, with respect to effectiveness, efficiency and safety in treatment of gastric carcinoma. Future studies involving RG should focus on decreasing operative time and reducing cost. Moreover, there is a need for randomized controlled trials comparing the two techniques with long-term follow-up.

• Journal of the Korean Society of Environmental Restoration Technology
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• 제15권6호
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• pp.29-41
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• 2012

This study was conducted in Ningxia Hui autonomous region, located at southern part of Mu Us sand land in China. To investigate relationships between windbreak effect and installation cost of sand barriers, plastic net is utilized by using four kind of heights (0.2, 0.3, 0.4 and 0.5m) and four kind of porosities (20, 30, 50 and 70%). These heights and porosities are measured for estimating distances for effective windbreak. It is shown that porosity and the distance have a positive relationship at same heights and porosity on ground indicates a constant figure when height reaches a certain level, regardless of the porosity. This implies that there is a difference of level of windbreak with different porosities; however, distance of windbreak effect is same at the same height of sand barrier. As a result of comparison between porosity of sand barrier on the ground and installation cost in each sand barrier with various heights and porosities (16 combinations), 0.4m and 0.5m height sand barriers describe highest economical efficiency. Within two variables, we concluded that height has a higher impact on windbreak effect than porosity.

• Asian-Australasian Journal of Animal Sciences
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• 제19권6호
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• pp.865-871
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• 2006

Signs of dental discolouration, difficulty in mastication, bony exostosis and debility were observed in cattle from Qingtongxia Ningxia, China where fluoride concentration in drinking water, soil, fodder, serum, bone, teeth, haircoat and urine were significantly higher than the corresponding health site. The problem of fluorosis in beef cattle is attributable to water containing toxic levels of fluoride. The objective of this paper was therefore to evaluate the influence of fluoride on erythrocyte parameters in cattle under high fluoride and low selenium conditions, as well as the protective efficacy of selenium exposure in feedstuff for bovine endemic fluorosis. Sixteen 6 to 7 year-old high fluoride beef cattle were randomly allotted into two groups each with eight cows: high fluoride control group, and supplemented with 0.25 mg/kg selenium per day for 83 days respectively. In addition, eight 6 to 7 year-old normal control beef cattle were selected from a non-high fluoride site. Blood samples were collected on day 0, 30 and 83 for erythrocyte parameters analysis and scanning electronic microscopy. The results indicated that erythrocytes, hemoglobin, packed cell volume values and $Na^+-K^+$ ATPase activity from affected cattle on the high fluoride site were significantly reduced during the period as compared with the corresponding samples of normal control cattle, a great number of echinocytes were present in peripheral blood, and subsequent anaemia. However, affected cattle exposed to selenium revealed increasable erythrocyte parameters, the extent of elevation in these values being dependent on the duration of supplementation with selenium. These findings suggest that fluoride exposure can cause erythrocyte damage, whereas selenium supplementation can antagonize fluoride-induced generation of free radicals and cumulative effects of lipid peroxidation in erythrocytes. Selenium supplementation may help to alleviate the possible hazards associated with bovine endemic fluorosis.