Journal articles on the topic 'Ordered Cluster Sampling'
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Barua, Prabal, and Syed Hafizur Rahman. "LIVELIHOOD SECURITY DETERMINANTS OF THE ORGANIC FARM HOUSEHOLD IN SOUTH-EASTERN COAST OF BANGLADESH." Food & Agribusiness Management 2, no. 1 (November 13, 2020): 01–05. http://dx.doi.org/10.26480/fabm.01.2021.01.05.
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Organic farming is a method of crop and livestock production that that sustains the demands of production of healthy and safe food for the community. Bangladesh is now highly productive area for agriculture production in the world with large varieties of agriculture crops are vultivating here. The study employed ordered logistic regression to assessed the determinants of livelihood security of the organic farm households in the south-eastern coast of Bangladesh. The study was conducted in three upazilas of Chattogram district like Banskhali, Anwara and Sitakund. Multistage sampling technique was adopted for the study. Three upazilas were selected and from each selected upazila a cluster of 1-2 villages were selected at random. At the last stage 150 respondents were selected from a cluster of villages using random proportional sampling. Ordered logistic regression was applied to assess the determinants of the livelihood security. Landholding, distance access to market, possession of livestock were the significant determinants of livelihood security for the organic farm households in South-eastern coast of Bangladesh . Livelihood security of the organic farm households in coastal Bangladesh was influenced significantly by the determinants like landholding, access to market distance and possession of livestock.
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Pallanca, Cristina, Silvia Leanza, Francesco R. Ferraro, Barbara Lanzoni, Emanuele Dalessandro, Mario Cadelano, Enrico Vesperini, et al. "Internal Kinematics and Structure of the Bulge Globular Cluster NGC 6569 ∗." Astrophysical Journal 950, no. 2 (June 1, 2023): 138. http://dx.doi.org/10.3847/1538-4357/accce9.
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Abstract In the context of a project aimed at characterizing the properties of star clusters in the Galactic bulge, here we present the determination of the internal kinematics and structure of the massive globular cluster NGC 6569. The kinematics has been studied by means of an unprecedented spectroscopic data set acquired in the context of the ESO-VLT Multi-Instrument Kinematic Survey of Galactic globular clusters, combining the observations from four different spectrographs. We measured the line-of-sight velocity of a sample of almost 1300 stars distributed between ∼0.″8 and 770″ from the cluster center. From a subsample of high-quality measures, we determined the velocity dispersion profile of the system over its entire radial extension (from ∼5″ to ∼200″ from the center), finding the characteristic behavior usually observed in globular clusters, with a constant inner plateau and a declining trend at larger radii. The projected density profile of the cluster has been obtained from resolved star counts, by combining high-resolution photometric data in the center, and the Gaia EDR3 catalog radially extended out to ∼ 20 ′ for a proper sampling of the Galactic field background. The two profiles are properly reproduced by the same King model, from which we estimated updated values of the central velocity dispersion, main structural parameters (such as the King concentration, the core, half mass, and tidal radii), total mass, and relaxation times. Our analysis also reveals a hint of ordered rotation in an intermediate region of the cluster (40″ < r < 90″, corresponding to 2r c < r < 4.5r c ), but additional data are required to properly assess this possibility.
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Treml, Leonardo De Marino, Anadia Cattarin, Renato Marques, Franklin Galvão, Lucas Batista Crivellari, and Vinicius Morais Coutinho. "FLORISTIC SIMILARITY IN A FOREST-SAVANNAH ECOTONE IN WESTERN BAHIA STATE, BRAZIL." FLORESTA 52, no. 4 (October 7, 2022): 475. http://dx.doi.org/10.5380/rf.v52i4.80286.
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This study aimed to generate knowledge about transition areas between phytophysiognomies for the understanding and conservation of these unique environments. Thus, the existence of different floristic groups was analyzed in a spatial gradient of an ecotone in the municipality of São Desidério, state of Bahia, Brazil. To this end, a transect of approximately 4.7 km, with orientation from Northeast to Southwest, was established along a spatial gradient. Twelve (12) 10x50 m sampling plots (500 m² each) were distributed throughout this transect. The following methodology was employed: First, the floristic similarity between the sampling plots was measured. These sampling plots were then grouped and the data were graphically presented in a dendrogram (Cluster analysis) and an ordering diagram (nMDS). Finally, the phytosociological parameters by ordered group were obtained. The results showed the presence of three floristic groups: Groups I, II and III, classified as wooded savannah, seasonal deciduous forest, and forested savannah, respectively. The floristic groups were formed gradually along the spatial gradient, and transition between phytophysiognomies does not occur abruptly, since the ordering by groups is more due to the difference between the abundance of species than to their presence and/or absence. The distribution pattern of the phytophysiognomies along the spatial gradient indicates association with abiotic factors, such as the pedological characteristics and the relief found along the transect, possibly creating an environmental gradient.
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Rabbi, Mohammad Fazle, Judit Oláh, József Popp, Domicián Máté, and Sándor Kovács. "Food Security and the COVID-19 Crisis from a Consumer Buying Behaviour Perspective—The Case of Bangladesh." Foods 10, no. 12 (December 10, 2021): 3073. http://dx.doi.org/10.3390/foods10123073.
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Since COVID-19 was confirmed in Bangladesh in March 2020, the government have enacted stringent measures to prevent the spread of the coronavirus, which has had a significant impact on people’s lives. Food consumption habits of consumers have shifted as a result of declining grocery shopping frequency, negative income shock, and food prices shooting up. This paper aims to explore Bangladeshi consumers’ buying behaviour in association with the stress generated from a food supply shortage during the COVID-19 pandemic and the post-outbreak perception of the food industry, using a dataset with 540 online samples collected between July and August 2021. A two-stage cluster sampling method and self-administrated questionnaire techniques were adopted for collecting the data during the third wave of COVID-19. Using partial least squares path modelling (PLS-PM) and multivariate multiple ordered logit regression (MVORD) to reveal the pertinent structure between all the blocks, this study provides two key findings. First, a higher intensity of COVID-19 impact translates into higher food stress associated with income reduction and higher food prices. Second, food stress directly affects consumer buying and consumption behaviour. We strongly recommend connecting consumers with local producers and collective use of shared warehouses through institutions, policies, and reforms to prevent disruption in the food supply chain and to keep food prices stable. Additionally, food producers, distributors, stakeholders, and policy planners should strengthen the food supply chain to stabilize food security.
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Bernacki, Katarzyna, Chakrapani Kalyanaraman, and Matthew P. Jacobson. "Virtual Ligand Screening against Escherichia coli Dihydrofolate Reductase: Improving Docking Enrichment Using Physics-Based Methods." Journal of Biomolecular Screening 10, no. 7 (September 16, 2005): 675–81. http://dx.doi.org/10.1177/1087057105281220.
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Motivated by their participation in the McMaster Data-Mining and Docking Competition, the authors developed 2 new computational technologies and applied them to docking against Escherichia coli dihydrofolate reductase: a receptor preparation procedure that incorporates rotamer optimization of side chains and a physics-based rescoring procedure for estimating relative binding affinities of the protein-ligand complexes. Both methods use the same energy function, consisting of the all-atom OPLS-AA force field and a generalized Born solvent model, which treats the protein receptor and small-molecule ligands in a consistent manner. Thus, the energy function is similar to that used in more sophisticated approaches, such as free-energy perturbation and the molecular mechanics Poisson-Boltzmann/surface area, but sampling during the rescoring procedure is limited to simple energy minimization of the ligand. The use of a highly efficient minimization algorithm permitted the authors to apply this rescoring procedure to hundreds of thousands of protein-ligand complexes during the competition, using a modest Linux cluster. To test these methods, they used the 12 competitive inhibitors identified in the training set, plus methotrexate, as positive controls in enrichment studies with both the training and test sets, each containing 50,000 compounds. The key conclusion is that combining the receptor preparation and rescoring methods makes it possible to identify most of the positive controls within the top few tenths of a percent of the rank-ordered training and test set libraries.
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Zakka, Kaku, and Romy O. Okoye. "COMPARISON OF RELIABILITY COEFFICIENTS OF TESTS CONSTRUCTED USING DIFFERENT ORDERINGS OF DIFFICULTY OF TEST ITEMS." International Journal of Education and Social Science Research 06, no. 03 (2023): 248–55. http://dx.doi.org/10.37500/ijessr.2023.6321.
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The study compared reliability coefficients of tests constructed using different orderings of difficulties of test items for English language and Mathematics in the North-East, Nigeria. Experimental research design was adopted. The population of the study comprised all the 5,403 JSS 3 students of 2021/2022 academic session in the fifteen Unity schools of the zone. The sample used for experimental study consisted of three hundred and seventy-five students obtained through a combination of multi-stage and cluster sampling techniques. Two instruments (one for each of the subjects) were used for the study. Each instrument was prepared in three different formats, titled: Mathematic Achievement Test and English Language Achievement Test. Each format of the instruments was subjected to test-retest reliability. Method of data analysis was Pearson Product Moment Correlation coefficient (PPMC). The reliability estimate that were obtained from the mathematics multiple-choice questions are as follows: FORMAT ETD (0.512), DTE (0.849) and MDI (0.718). The reliability estimate that were obtained from the English language multiple-choice questions are as follows: FORMAT ETD ETD (0.728), DTE (0.669) and MDI (0.877). The study recommends that for English Language, items ordered from easy to difficult format should be used when constructing test items; since it was the one that had the highest reliability coefficient; for Mathematics items format from difficulty to easy should be used since it has the highest reliability coefficient among the test items format.
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Harsej, Zahra, Nasrin Mokhtari Lakeh, Farzaneh Sheikholeslami, and Ehsan KazemnezhadLeili. "Internet Addiction and Its Relationship with Family Functioning in High School Students." Journal of Holistic Nursing And Midwifery 31, no. 1 (January 1, 2021): 44–52. http://dx.doi.org/10.32598/jhnm.31.1.2025.
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Introduction: Family-related factors play an important role in adolescent’s addiction to the Internet. Objective: The aim of this study was to examine the relationship between Internet addiction and family functioning in high school students. Materials and Methods: This is an analytical study with a cross-sectional design conducted on 796 high school students in Rasht city, Iran who were selected using multi-stage cluster random sampling method. Data collection tools were a demographic form, the Young’s Internet Addiction Test, and the Family Assessment Device. Chi-Square test and rank-ordered logistic regression analysis were used for data analysis. Results:The response rate of of students was 86.81%; 85.7% had at least two family members who were using the Internet; 71.2% of students had no addiction, 27.5% were exposed to Internet addiction and 1.3% had Internet addiction. The majority (65.0%) of studnets had unhealthy family functioning. The relationship between Internet addiction and family functioning was statistically significant (P=0,001). There was a significant statistical relationship between Internet addiction and family income (P= 0.003), fatherchr('39')s job (P=0.001), and duartion of internet usage per day (P=0.001). Logistic regression model showed that the family functioning score (OR=1.02, 95% CI;1.01-1.04, P=0.001), duration of Internet usage per day (OR=1.02, 95% CI;1.11-1.20, P=0.0001), and gender (male) (OR=1.02, 95% CI;1.26-2.58, P=0.001) significantly affected Internet addiction. Conclusion:Due to the direct statistical relationship between Internet addiction and family functioning, it is necessary to pay serious attention to the phenomenon of Internet addiction and make appropriate plans for adolescents and their families to use the Internet properly.
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Kaveh, Sepideh, Abbas Assari Arani, Sajjad Faraji Dizaji, and Seyed Hasan Hoseini. "Determinants of Subjective Well-being: Do we Really Know What Makes People Happy? A Study on Rasht Metropolis, North of Iran." Journal of Research & Health 11, no. 1 (February 1, 2021): 11–20. http://dx.doi.org/10.32598/jrh.11.1.1691.1.
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Background: Background: Recently, along with traditional economic indicators, policymakers are increasingly dealing with Subjective Well-Being (SWB) as an evaluation criterion of their performance and as an index for the population’s psychology health. This was done to define different determinants of SWB with a focus on some specific aspects of the living area. Also, this article investigateed the effect of urban and outskirts area on SWB. Method: This study is a cross-sectional study based on a structured interview and the samples (219 people ) were selected by a two-stage cluster sampling method in 2018 in Rasht city, a metropolis in Iran. In designing the local questionnaire, Gallup’s Global Emotions questionnaire has been used. Two main contributions of this study are defining culturized and proper indices for measuring SWB, and the financial status of people while Iranian people used to understate their real income. Data analysis was conducted using STATA 14.2 applying Descriptive statistics, Correlation study, Ordered Probit regression Method. Results: Results show that improving the socio-economic status of people improve SWB. Having financial satisfaction, satisfaction with leaving area, being tenure, and living in more spacious residency have positive effects on SWB. Also, the city dwellers were found to have higher SWB (5.23 out of 7) than outskirt dwellers (4.9 out of 7) while keeping the other factors to be constant. They reported the same differences in positive feelings and negative feelings indices. Conclusion: The welfare policies should be revised to improve the financial status of all people, and increase the access to urban facilities for outskirts’ dwellers.Determinants of Subjective Well-being: Do we Really Know What Makes People Happy? A Study on Rasht Metropolis, North of Iran
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Bergendahl, M., A. Iranmanesh, W. S. Evans, and J. D. Veldhuis. "Short-Term Fasting Selectively Suppresses Leptin Pulse Mass and 24-Hour Rhythmic Leptin Release in Healthy Midluteal Phase Women without Disturbing Leptin Pulse Frequency or Its Entropy Control (Pattern Orderliness)1." Journal of Clinical Endocrinology & Metabolism 85, no. 1 (January 1, 2000): 207–13. http://dx.doi.org/10.1210/jcem.85.1.6325.
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Nutritional signals strongly regulate neuroendocrine axes, such as those subserving release of LH, GH, and TSH, presumptively in part via the adipocyte-derived neuroactive peptide leptin. In turn, leptin release is controlled by both acute (fasting) and long-term (adipose store) nutrient status. Here, we investigate the neuroendocrine impact of short-term (2.5-day) fasting on leptin release in healthy young women studied in the steroid-replete midluteal phase of the normal menstrual cycle. Eight women each underwent 24-h blood sampling at 10-min intervals during a randomly ordered 2.5-day fasting vs. fed session in separate menstrual cycles. Pulsatile leptin release was quantified by model-free Cluster analysis, the orderliness of leptin patterns by the approximate entropy statistic, and nyctohemeral leptin rhythmicity by cosinor analysis. Mean (24-h) serum leptin concentrations fell by 4.6-fold during fasting; namely, from 15.2 ± 2.3 to 3.4 ± 0.6 μg/L (P= 0.0007). Cluster analysis identified 13.9 ± 1.1 and 14.3± 1.1 leptin peaks per 24 h in the fed and fasting states (P = NS), and unchanging leptin interpeak intervals (89 ± 5.4 vs. 92 ± 5.3 min). Leptin peak area declined by 4.2-fold (155 ± 21 vs. 37 ± 7 area units, P = 0.004), due to a reduction in incremental leptin pulse amplitude (4.4 ± 0.7 vs. 1.0 ± 0.13 μg/L, P = 0.0011). The cosine amplitude and mesor (mean) of the 24-h leptin rhythm decreased by 4-fold, whereas the acrophase (timing of the nyctohemeral leptin peak) remained fixed. The approximate entropy of leptin release was stable, thus indicating preserved orderliness of leptin release patterns in fasting. Cross-correlation analysis revealed both positive (fed) and negative (fasting) leptin-GH relationships, but no leptin-LH correlations. In summary, short-term (2.5-day) fasting profoundly suppresses 24-h serum leptin concentrations and pulsatile leptin release in the sex steroid-sufficient midluteal phase of healthy women via mechanisms that selectively attenuate leptin pulse area and incremental amplitude. In contrast, the pulse-generating, nyctohemeral phase-determining, and entropy-control mechanisms that govern 24-h leptin release are not altered by acute nutrient restriction at this menstrual phase. Leptin-GH (but not leptin-LH) showed nutrient-dependent positive (fed) and negative (fasting) cross-correlations. Whether similar neuroendocrine mechanisms supervise altered leptin signaling during short-term nutrient restriction in men, children, or postmenopausal women is not known.
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Marwiya, Arfatul, Zulkifli Zulkifli, Sugito Sugito, and Muslim Muslim. "ANALISIS ESTETIS KARYA KERAJINAN KAIN PERCA SISWA KELAS VII SMP NEGERI 1 BERINGIN KABUPATEN DELI SERDANG." Gorga : Jurnal Seni Rupa 7, no. 2 (December 30, 2018): 267. http://dx.doi.org/10.24114/gr.v7i2.11894.
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AbstrakPenelitian ini bertujuan untuk meningkatkan hasil belajar siswa pada pelajaran prakarya, khususnya pada materi pelajaran kerajinan limbah kain perca dan mengetahui pemanfaatan limbah kain perca menjadi produk kerajinan tangan kain perca sarung kotak tisu dan mengetahui kualitas estetis karya kerajinan tangan kain perca sarung kotak tisu yang dihasilkan siswa kelas VII SMP Negeri 1 Beringin Kabupaten Deli Serdang. Penelitian ini menggunakan metode penelitian kualitatif dengan sampel 20 karya kerajinan kain perca sarung kotak tisu siswa kelas VII yang diambil menggunakn teknik Cluster Random Sampling. Instrumen penelitian ini menggunakan tes membuat karya kerajinan kain perca sarung kotak tisu. Teknik analisis data yang digunakan analisis deskriptif.Berdasarkan hasil penelitian dapat disimpulkan bahwa secara keseluruhan siswa telah menghasilkan karya kerajinan limbah kain perca berupa sarung kotak tisu. Secara keseluruhan tingkat kualitas estetis karya kerajinan kain perca pada kelas VII-1 SMP Negeri 1 Beringin Kabupaten Deli Serdang yaitu dari aspek bentuk, warna, ornamen/hiasan, dan nilai fungsi dikategorikan cukup baik. Dari aspek bentuk kerajinan secara umum memperoleh jumlah nilai rata-rata cukup baik karena, secara keseluruhan bentuk dari karya kerajinan sarung kotak tisu siswa belum tersususn secara baik dalam kesatuan yang harmonis dan bentuk yang sempurna. Aspek warna secara umum memperoleh nilai rata-rata cukup baik, karena secara keseluruhan warna dari karya kerajinan sarung kotak tisu siswabelum terdapat warna yang harmonis dan kesesuaian warna dengan unsur lain. Aspek ornamen atau hiasan secara umum memperoleh jumlah nilai rata-rata cukup baik, karena secara keseluruhan ornamen atau hiasan dari karya kerajinan sarung kotak tisu siswa tampak kurang rapi, unik, menarik dan harmonis dengan unsur lain. Dan aspek nilai fungsi secara umum memperoleh jumlah nilai rata-rata cukup baik, namun secara keseluruhan nilai fungsi dari karya kerajinan sarung kotak tisu siswa sudah memiliki nilai fungsi yang ergonomis.Kata Kunci: nilai estetis, kerajinan, kain percaAbstractThis study aims to improve students’ learning achievement at the craft lesson, especially for the lesson material about the handicraft made of rag and to find out the use of the rag in order to make one handicraft product, namely sarong tissue boxes and to find out the aesthetic quality of sarong tissue boxeshandicraft made of rag, which is made by students of seventh (VII) grade of SMP Negeri 1 Beringin Deli Serdang. The study used qualitative research design with 20 products of rag sarong tissue boxes made by seventh (VII) grade students which is taken by using cluster random sampling technigue. The instrument of the study use a test how to make rag sarong tissue boxes. The technigue of data analysis is descriptive analysis. Based on the research finding, it is concluded that all the students made rag sarong tissue boxes handicraft the level 07. The aesthetic quality on them made by VII-1 classs SMP Negeri 1 Beringin Deli Serdang which consist of some aspects, namely shape, colour, ornament/decoration, and function value can be categoryzed at fair level. From the shape aspect totally is got the fair score because the shape of all rag sarong tissue boxes have ast been ordered well in harmonious unity and perfect form. The colour aspect is got the fair score, because totally the colour of students’ rag sarong tissue boxes handicraft have not used harmonious calour and unmatching colour to another element. Overall, the ornament aspect or decoration got fair score, because all the ornaments or the decoration of students’ rag sarong tissue boxes handicraft looked less neat, less unigue and less atractive and less harmonic to another element and the function value aspect got fair score but overall the function value of the students’ rag sarong tissue boxes already had ergnoic function value.Keywords: aesthetic value, patchworks craft
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Liu, Minshi, Yi Long, Ling Zhang, and Guifang He. "A Method for extracting multi-scale stay feature of trajectory based on OPTICS." Abstracts of the ICA 1 (July 15, 2019): 1. http://dx.doi.org/10.5194/ica-abs-1-222-2019.
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<p><strong>Abstract.</strong> With the popularity of mobile positioning devices, mobile trajectory data is rapidly increasing. The trajectory stay feature extraction is to find the staying part of the moving object from the moving trajectory, which is the basis of the semantic matching of the staying segment. The trajectory stay segment extraction can be used to analyze tourist visit recommendation and mode, special landmark extraction such as gas station, destination prediction, rental car passenger advice, and even traffic guidance. Most existing researches extract the single-scale stay feature of the trajectory through the spatiotemporal characteristics of the trajectory or the geographical environment. However, the stay feature of the trajectory is multi-scale. For example, at a city scale, the stay of a tourist trajectory is composed of several scenic spots; however, at the scenic scale, a scenic stop may contain a number of subtle attraction. Therefore, this paper proposes to extract trajectory multi-scale stay feature based on OPTICS method. Since the trajectory data is different from the conventional discrete point set, but an ordered point string, the OPTICS method needs to be modified to accommodate the clustering of the trajectory point string. Method improvements include the following four aspects:</p><p>(1)The correction of the two-point distance definition of the trajectory. Since the trajectory points are ordered, thedistance between the two points of the trajectory is not the linear distance between the two points, but the sum of thelengths of the trajectory polylines between the two points.</p><p>(2)The count calculation of points in the ε neighborhood of the center points needs to be improved. When the timeinterval of the trajectory is equal, the calculation method is consistent with OPTICS; and when the time interval of thetrajectory sampling is not equal, the number of points represented by one trajectory points should be related to its timeinterval. When the time interval is large, the point should represent more points. Therefore, a time coefficient is defined,which is defined as the ratio of the track point time interval to the basic time interval. The total number of the points isthe sum of time coefficient m of each points. By improving as above, the algorithm can be adapted to trajectory datasampled at unequal time intervals. In addition, when searching for the field of points, it is not necessary to search theentire set of trajectory points, but only need to start with the center point, and search forward and backward until thedistance between the two points is greater than the threshold ε.</p><p>(3)Improvement of clustering order method: When generating the clustering order, the OPTICS needs to center thecurrent point in order, and correct the reachable distance value of each point in the ε neighborhood of the point, then thepoint at the minimum distance is selected as the subsequent point. For the trajectory data, the subsequent point on thetrajectory is obviously the point which the reachable distance is the shortest in the ε neighborhood of the current point,and so the clustering order is consistent with the trajectory points sequence. Therefore, the improved algorithm only needsto calculate the reachable distance of a subsequent point of the current point, thereby quickly generating a clusteringsequence.</p><p>(4)The scale of the staying feature is automatically controlled by reachable distance. Although the OPTICS is capableof generating multi-level clustering results, it does not measure the hierarchy. In this paper, the scale of each stay featureis measured by the reachable distance range of a cluster, and the relationship between the reachable distance and the stayfeature scale is established, so that the multi-scale stay feature can be obtained automatically.</p><p>This paper compares this method with other methods using a variety of trajectory data. The results show that the method can extract the track stay feature faster and more accurately, and can automatically control the stay feature extraction level.</p>
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Ding, Yao, Yin Wang, Shuming Yang, Xiaolong Zhao, Lili Ouyang, and Chengyue Lai. "Evaluating Surface Water Nitrogen Pollution via Visual Clustering in Megacity Chengdu." Water 15, no. 11 (June 2, 2023): 2113. http://dx.doi.org/10.3390/w15112113.
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The current standards used for nitrogen pollution evaluation are lacking, and scientific classification methods are needed for nitrogen pollution to improve water quality management capabilities. This study addresses the important issue of assessing surface water nitrogen pollution by utilizing two advanced multivariate statistical techniques: self-organizing maps (SOMs) obtained using the K-means algorithm and the Hasse diagram technique (HDT). The research targets of this study are the rivers of the megacity Chengdu, China. Samples were collected on a monthly basis in 2017–2020 from different sites along the rivers, and their nitrogen pollution parameters were determined. The grouping of nitrogen pollution parameters and the clustering of sampling events using SOMs facilitate the preprocessing required for the HDT, wherein clusters are ordered according to the pre-clustered water sampling events. The results indicate that nitrogen pollution in the Chengdu River Basin, which is prominent and mainly driven by nitrate nitrogen, can be categorized into five levels. The nitrogen pollution in Tuo River is serious. Although the degree of ammonia nitrogen pollution in Jin River is higher, the pollution range is smaller. Furthermore, these results were evaluated by the SOMs and HDT to be clear and reliable. Overall, these findings can provide a basis for local environmental legislation.
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Jones, Laurel, Michael Tynes, and Paul Smith. "Prediction of models for ordered solvent in macromolecular structures by a classifier based upon resolution-independent projections of local feature data." Acta Crystallographica Section D Structural Biology 75, no. 8 (July 30, 2019): 696–717. http://dx.doi.org/10.1107/s2059798319008933.
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Current software tools for the automated building of models for macromolecular X-ray crystal structures are capable of assembling high-quality models for ordered macromolecule and small-molecule scattering components with minimal or no user supervision. Many of these tools also incorporate robust functionality for modelling the ordered water molecules that are found in nearly all macromolecular crystal structures. However, no current tools focus on differentiating these ubiquitous water molecules from other frequently occurring multi-atom solvent species, such as sulfate, or the automated building of models for such species. PeakProbe has been developed specifically to address the need for such a tool. PeakProbe predicts likely solvent models for a given point (termed a `peak') in a structure based on analysis (`probing') of its local electron density and chemical environment. PeakProbe maps a total of 19 resolution-dependent features associated with electron density and two associated with the local chemical environment to a two-dimensional score space that is independent of resolution. Peaks are classified based on the relative frequencies with which four different classes of solvent (including water) are observed within a given region of this score space as determined by large-scale sampling of solvent models in the Protein Data Bank. Designed to classify peaks generated from difference density maxima, PeakProbe also incorporates functionality for identifying peaks associated with model errors or clusters of peaks likely to correspond to multi-atom solvent, and for the validation of existing solvent models using solvent-omit electron-density maps. When tasked with classifying peaks into one of four distinct solvent classes, PeakProbe achieves greater than 99% accuracy for both peaks derived directly from the atomic coordinates of existing solvent models and those based on difference density maxima. While the program is still under development, a fully functional version is publicly available. PeakProbe makes extensive use of cctbx libraries, and requires a PHENIX licence and an up-to-date phenix.python environment for execution.
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Chandra, Girish, Neeraj Tiwari, and Raman Nautiyal. "Two stage adaptive cluster sampling based on ordered statistics." Advances in Methodology and Statistics 16, no. 1 (January 1, 2019). http://dx.doi.org/10.51936/wuqh7533.
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The estimation problem on sparsely distributed populations using adaptive cluster sampling (ACS) is discussed. In the first phase of ACS, two stage sampling is used in which primary and secondary sampling units are selected using simple random sampling without replacement. The idea of Thompson (1996) is introduced in order to choose an appropriate fixed value of pre-specified condition, which might represent the number of rare species, before conducting the survey by the use of order statistics. Different estimators of the population mean under the two possible schemes (open and closed boundaries of primary sampling units) are studied and the Rao-Blackwell theorem for improving these estimators is also used. Numerical illustrations, one on real life data and the other based on simulation study, are discussed for these two schemes. This design may be quite useful in environmental, forestry and other areas of research dealing with rare, endangered or threatened species.
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Mimar, Sayat, and Gourab Ghoshal. "A sampling-guided unsupervised learning method to capture percolation in complex networks." Scientific Reports 12, no. 1 (March 9, 2022). http://dx.doi.org/10.1038/s41598-022-07921-x.
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AbstractThe use of machine learning methods in classical and quantum systems has led to novel techniques to classify ordered and disordered phases, as well as uncover transition points in critical phenomena. Efforts to extend these methods to dynamical processes in complex networks is a field of active research. Network-percolation, a measure of resilience and robustness to structural failures, as well as a proxy for spreading processes, has numerous applications in social, technological, and infrastructural systems. A particular challenge is to identify the existence of a percolation cluster in a network in the face of noisy data. Here, we consider bond-percolation, and introduce a sampling approach that leverages the core-periphery structure of such networks at a microscopic scale, using onion decomposition, a refined version of the k-core. By selecting subsets of nodes in a particular layer of the onion spectrum that follow similar trajectories in the percolation process, percolating phases can be distinguished from non-percolating ones through an unsupervised clustering method. Accuracy in the initial step is essential for extracting samples with information-rich content, that are subsequently used to predict the critical transition point through the confusion scheme, a recently introduced learning method. The method circumvents the difficulty of missing data or noisy measurements, as it allows for sampling nodes from both the core and periphery, as well as intermediate layers. We validate the effectiveness of our sampling strategy on a spectrum of synthetic network topologies, as well as on two real-word case studies: the integration time of the US domestic airport network, and the identification of the epidemic cluster of COVID-19 outbreaks in three major US states. The method proposed here allows for identifying phase transitions in empirical time-varying networks.
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Rana Ejaz Ali Khan, Tusawar Iftikhar Ahmad, Sara Noreen, and Aymen Ejaz. "Factors associated with the quality of antenatal care (ANC) services use in Bahawalpur." Journal of the Pakistan Medical Association, October 14, 2020, 1–8. http://dx.doi.org/10.47391/jpma.645.
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Abstract
A cross sectional study was conducted from October 2016 to February 2017 with the aim to examine the factors affecting the quality of antenatal care (ANC) services being used in Bahawalpur district.
Data was collected using the Stratified cluster sampling technique from 1,650 married women of reproductive age (15-49 years) who had given birth to at least one child in four preceding years. Information regarding socioeconomic aspects and the ANC services used during pregnancy were recorded through interviews. The quality of ANC services being used was measured through constructing an index.
The results from multivariate ordered logistic regression analysis revealed that longer birth interval, gender of the eldest child (female), birth order of the child (as first or second child), number of living sons, the woman’s knowledge about complications of pregnancy, her prior history of neonatal mortality, her socioeconomic empowerment, and Continuous...
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Cheng, Minghui, Wenli Su, Huiju Li, Linjie Li, Minghui Xu, Xue Zhao, Mengdie Han, and Li Yang. "Factors influencing the social participation ability of rural older adults in China: A cross-sectional study." Frontiers in Public Health 10 (January 4, 2023). http://dx.doi.org/10.3389/fpubh.2022.1001948.
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ObjectiveTo investigate the epidemiology and influencing factors of social participation ability of rural older adults in China.MethodsFrom March to April 2021, 3450 older adults in poverty aged 60 and above registered in Jishishan County (J County) were selected by cluster sampling for a cross-sectional questionnaire survey and their social participation ability was assessed using the Ability Assessment of older adults (MZ/T039-2013). The results were statistically analyzed and an ordered multi-category logistic regression analysis was used to analyze the effect of influencing factors on the social participation ability of rural older adults.Results3,346 questionnaires were collected, with an effective recovery rate of 96.99%. Out of all the participants, 1,355 (40.5%) of the 3,346 cases had intact social participation ability, while 1,991 (59.5%) had different degrees of loss of social participation ability, of which 1,393 (41.14%) were mildly impaired, 419 (12.5%) were moderately impaired and 179 (5.3%) were severely impaired. Age, educational level, religious belief, living status, whether suffering from dementia and the occurrence of accidents in recent 30 days were influencing factors on the social participation ability (p < 0.05).ConclusionThe rate of impaired social participation ability among older adults was >50% and age, educational level, religious beliefs, living status, whether suffering from dementia, and the occurrence of accidents in recent 30 days (such as falls, choking, loss) were significant factors influencing the ability of social participation of rural older adults.
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Wang, Shuhong, Hongjun Zhao, and Zesheng Sun. "Working intentions of medical students in response to healthcare workplace violence and descending resources reform in China." BMC Medical Education 22, no. 1 (May 9, 2022). http://dx.doi.org/10.1186/s12909-022-03428-1.
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Abstract Background In order to curb healthcare workplace violence (WPV) and better allocate healthcare resources, China launched the descending resources reform in 2013 and tightened the anti-violence legal environment simultaneously. Medical students are expected to reconsider their working intentions of entering the medical market (inter-market effect) and choosing high- or low-level hospitals (intra-market effect) in response to the evolving WPV. The goal of this study was to explore the link between the perceived WPV incidence and medical students’ willingness to practice medicine in the context of China’s descending resources reform. Method Medical students were selected with cluster sampling from 8 medical colleges in Zhejiang Province, China, and 1497 valid questionnaires were collected by using a five-point unbalanced scale, to perform cross-sectional empirical research using the ordered logit model (OLM). Results The perceived WPV incidence negatively correlate with the willingness of medical students to practice medicine but positively correlate with their willingness to practice in low-level hospitals, indicating the existence of inter- and intra-market effects. The anti-violence legal environment has no direct link with working intention but contributes to the perceived decline in the incidence of violence. Descending resources reform has simultaneous opposite effects on medical students, with the coexistence of prudent motives driven by reform costs and optimistic expectations of sharing external benefits. Conclusions Safety needs and risk aversion motive play an important role in medical students’ career choice when facing severe WPV. Tightening of the anti-violence legal environment and the descending resources reform could drive medical students to low-level hospitals.
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Onyemma, Juliet Ogadinma, Koko Michael Tertsea, Nkem Kelechi Ogbonna, and Nwafor Solomon Chimela. "Level of Adoption of Improved Cassava Technologies in Benue State." Journal of Applied Life Sciences International, June 14, 2019, 1–13. http://dx.doi.org/10.9734/jalsi/2019/v21i230099.
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Aims: The study aimed to determine the level of adoption of improved cassava technologies in Benue State.
Study Design: The Survey design was adopted for the study.
Place and Duration of Study: The study was carried out in Benue State, between September 2018 and March 2019.
Methodology: Cluster and simple random sampling techniques were used to select 336 respondents for the study. Primary data were collected using Semi-structured questionnaire. The objectives were achieved using descriptive statistics such as percentages, frequencies and means and Rank ordered analysis.
Results: The improved cassava technologies in Benue state were identified to include; TMS 0505, TMS 0581, TMS 30572, TMS 01/1368, TMS 96/1632, TMS 92/0326, TME 419, NR 8082.The result revealed that the percentage awareness for TMS 0505 was high 65% (238) but the adoption of TMS 0505 was low 32% (78). There is moderate awareness level for TMS 0581 49% (179) and TMS 02/1368 56% (294) with moderate adoption 55% (98) and 53% (109) respectively. Also, the awareness level for TMS 92/0326 is high 72% (265) with moderate adoption 44% (116); TME 419 and NR 8082 had high awareness level 85% (311) and 88% (323) with high adoption 65% (201) and 68% (221) respectively. The result also revealed that famers complained that the improved cassava varieties cannot store for a long time in the farm 93% (342) and that there is no market to sale increased quantity of cassava roots.
Conclusion: Thus it was concluded that there is generally high level of awareness of improved cassava varieties in Benue state but with moderate to low adoption rate.
The study thus recommend that farmers should be consulted and their needs should always be considered in such development ventures. This will ensure high adoption and high impact as well.
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Shahbaz, Pomi, Shamsheerul Haq, Azhar Abbas, Hossein Azadi, Ismet Boz, Mark Yu, and Susan Watson. "Role of farmers’ entrepreneurial orientation, women’s participation, and information and communication technology use in responsible farm production: a step towards sustainable food production." Frontiers in Sustainable Food Systems 7 (August 29, 2023). http://dx.doi.org/10.3389/fsufs.2023.1248889.
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Responsible production is essential for sustainable development and for ensuring global food security. The concept of responsible production has been well studied in other sectors of the economy, but has yet to gain recognition in the agricultural sector. Therefore, this study examined responsible production in the context of agriculture and the factors affecting responsible farm production in the developing country of Pakistan. Face-to-face interviews were conducted to collect data from 196 farmers selected using the multistage random sampling method. An independent sample t-test, chi-square test, and ordered probit model were used to analyze the data. The responsible farm production index was estimated based on the climate change adaptation, resource efficiency, carbon footprints, and economic returns of each farm. The mean value of the responsible farm production index is 0.69. The farmers were divided into low-, moderate-, and highly responsible farm producers using cluster analysis. More than 36% of farms were highly responsible. The results revealed that women’s participation in farming activities, extension services, the use of information and communication technologies, and farmer entrepreneurial orientation dimensions significantly affected responsible farm production. Farm producers using the Internet for agriculture had a 1.4% points higher probability of belonging to the highly responsible farm producer category compared to those who did not use the Internet to obtain agricultural information. Farms with women’s participation in agricultural activities were 33.5% points more likely to belong to the highly responsible farm producer category than farms where only males perform agricultural operations. Therefore, women’s empowerment and farmers’ entrepreneurial skills are absolute necessities of responsible farming. This study piques the interests of stakeholders while also adding to the scant body of knowledge on responsible farm production around the world. Furthermore, this study is critical for developing a roadmap for long-term sustainable agricultural development.
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Huang, Feifei, Wenxiu Sun, Yonglin Li, Lin Zhang, and Wei-Ti Chen. "Modification and validation of the COVID-19 stigma instrument in nurses: A cross-sectional survey." Frontiers in Psychology 14 (August 18, 2023). http://dx.doi.org/10.3389/fpsyg.2023.1084152.
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BackgroundNurses taking care of patients with infectious diseases have suffered from noticeable societal stigma, however currently, there is no validated scale to measure such stigma. This study aimed to revise and validate the COVID-19 Stigma Instrument-Nurse-Version 3 (CSI-N-3) by using item response theory (IRT) as well as classical test theory analysis.MethodsIn phase I, the Chinese CSI-N-3 was modified from the English version of HIV/AIDS Stigma Instrument-Nurse based on standard cross-cultural procedures, including modifications, translation/back translations, pilot testing, and psychometric testing with classical test theory and Rasch analysis. In phase II, a cross-sectional study using cluster sampling was conducted among 249 eligible nurses who worked in a COVID-19-designed hospital in Shanghai, China. The influencing factors of COVID-19-associated stigma were analyzed through regression analysis.ResultsIn phase I, the two-factor structure was verified by confirmatory factor analysis, which indicated a good model fit. The 15-item CSI-N-3 achieved Cronbach’s α of 0.71–0.84, and composite reliability of 0.83–0.91. The concurrent validity was established by significant association with self-reported physical, psychological, and social support levels (r = −0.18, −0.20, and −0.21, p < 0.01). In IRT analysis, the CSI-N-3 has ordered response thresholds, with the Item Reliability and Separation Index of 0.95 and 4.15, respectively, and the Person Reliability and Separation Index of 0.20 and 0.50, respectively. The infit and outfit mean squares for each item ranged from 0.39 to 1.57. In phase II, the mean score for the CSI-N-3 in Chinese nurses was 2.80 ± 3.73. Regression analysis showed that social support was the only factor affecting nurses’ COVID-19-associated stigma (standardized coefficients β = −0.21, 95% confidence interval: −0.73 ~ −0.19).ConclusionThe instrument CSI-N-3 is equipped with rigorous psychometric properties that can be used to measure COVID-19-associated stigma during and after the COVID-19 pandemic among nurses. The use of this instrument may facilitate the evaluation of tailored stigma-reduction interventions.