Academic literature on the topic 'Two phase multistage Sampling'
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Journal articles on the topic "Two phase multistage Sampling"
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Ali, Muhammad Sher Baz, Ashfaque Ahmad Shah, and Muhammad Sarwar. "Analysis of MPhil/PhD Supervisor's Relationship Development and Communication Competence." Global Social Sciences Review VI, no. I (March 30, 2021): 429–38. http://dx.doi.org/10.31703/gssr.2021(vi-i).43.
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The purpose of this research was to analyse the relationship development and communication competence of MPhil/PhD supervisors. A confirmatory mixed-methods research design was used to conduct the study in two stages. For both phases, 360 MPhil/PhD graduates and 72 supervisors were selected from four public universities in Punjab using a multistage sampling technique. Data were collected electronically from 239 MPhil/PhD graduates during phase-I using an adapted questionnaire from ASHA's supervision model, while in phase-II, 72 MPhil/PhD supervisors were interviewed to cross-check the Phase-I findings. According to MPhil/PhD graduates, their supervisors have relationship development and communication competence. During interviews, most MPhil/PhD supervisors refute their supervisees' claims and offer suggestions to improve supervisors' competence. Based on supervisor suggestions, the Higher Education Commission of Pakistan should revise the supervision structure, provide Postdoctoral fellowships to all supervisors, and promote international conferences. This study may be helpful to supervisors in self-evaluation as well as understanding relationship development and communication competence.
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Sulistiyawati, Tri, Budi Utomo, and Soeharto Soeharto. "Risk Factors of Children Behavior in Schistosomythical Transfer in Two Villages of Lindu Regency, Sigi District, Central Sulawesi in 2017." Folia Medica Indonesiana 54, no. 2 (July 5, 2018): 141. http://dx.doi.org/10.20473/fmi.v54i2.8865.
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Children of primary school are particularly vulnerable to schistosomiasis because 60-70% of them with age of 5-14 years do a lot of activity outside home. The impact of schistosomiasis in children are the lack of concentration in learning, anemia, and impaired growth. This study aimed to describe the behavior of children aged 7-12 years in Puro'o and Tomado Villages in preventing the transmission of schistosomiasis and to determine the correlation between age, sex behavior community in the prevention of schistosomiasis. The study was conducted in Tomado and Puro'o villages for 3 months from March to June 2016. This was a cross sectional study. The samples in this study were children aged 7-12 years, selected by stratified multistage random cluster sampling which was done in three phases: the first phase was the villages, the second phase was the primary school in the village, and the third stage was household selected by proportional random sampling. Data were collected through interview using a structured questionnaire and the observation was analyzed using chi-square test. Respondents who had less knowledge, mostly behave defecate/urinate (80%) in latrine/WC, handwashing behavior with soap after defecating/urinating (50%), wearing footwear outside the home (86.5%), and playing in the rice fields, marshes and lakes (67.3%). Analysis of the relationship between knowledge and child's behavior showed no significant relationship (p=0.114). As a conclusion, children aged 7-12 years in Tomado and Puro'o villages mostly had less supportive behavior in preventing the transmission of schistosomiasis and had moderate or less reliable knowledge.
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Hashemiparast, Mina, Ali Montazeri, Saharnaz Nedjat, Reza Negarandeh, Roya Sadeghi, Masoumeh Hosseini, and Gholamreza Garmaroudi. "Pedestrian Road-Crossing Behaviours: A Protocol for an Explanatory Mixed Methods Study." Global Journal of Health Science 8, no. 5 (August 23, 2015): 27. http://dx.doi.org/10.5539/gjhs.v8n5p27.
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<p><strong>BACKGROUND:</strong> Pedestrian crossing is an important traffic safety concern. The aim of this paper is to report the protocol for a sequential explanatory mixed methods study that set out to determine the pedestrians’ traffic behaviors, the associated factors and exploring the perception of young people about the traffic risky behaviors in crossing the road. The ultimate purpose of the study is to design a preventive and cultural based strategy to promote young people’s health.</p> <p><strong>METHODS:</strong> This is a sequential explanatory mixed methods design. The study has two sequential phases. During the first phase, a population-based cross-sectional survey of a sample of young people will be conducted using the proportional random multistage cluster sampling method, in Tehran, Iran. Data will be collected by a questionnaire including items on socio-demographic information, items on measuring social conformity tendency, and questions on subjective norms, attitudes, and perceived behavioral control based on the Theory of Planned behavior. In the second phase, a qualitative study will be conducted. A purposeful sampling strategy will be used and participants who can help to explain the quantitative findings will be selected. Data collection in qualitative phase will be predominately by individual in-depth interviews. A qualitative content analysis approach will be undertaken to develop a detailed understanding of the traffic risky behaviors among young pedestrians.</p> <p><strong>CONCLUSION: </strong>The findings of this explanatory mixed methods study will provide information on traffic risky behaviors in young pedestrians. The findings will be implemented to design a cultural based strategy and intervention programs.</p>
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Yeo, Kee-Jiar, and Shih-Hui Lee. "Development and Validation of an Instrument to Measure Parental Attitude and Health Beliefs Toward Sexuality Education." SAGE Open 13, no. 1 (January 2023): 215824402211394. http://dx.doi.org/10.1177/21582440221139470.
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The quality of sexuality education is significant in encouraging and expanding the knowledge of sexual and reproductive health (SRH). Parents’ attitudes and beliefs toward sexuality education contribute to the effectiveness of sexuality education in schools. Consequently, there is a need to provide a validated instrument to investigate parental attitude and beliefs toward school-based sexuality education. The objective of this study is to describe the development and test the psychometric properties of an instrument that measures the attitudes and beliefs of parents toward the implementation of sexuality education in primary schools within Malaysia. Items for the instrument in this study were developed through literature review via the deduction method. Data collection was conducted in two phases. The first phase involved 174 parents with children who were attending primary schools through convenience sampling. Then, the multistage sampling method was employed to collect data from 350 parents. Results from the exploratory factor analysis have identified four latent dimensions, which are attitude toward sexuality education, perceived benefits, perceived barriers, and self-efficacy, that support the SRH learning among primary school children. Confirmatory factor analysis demonstrates a good overall fit with the application of post hoc modifications. The results also indicate that the instrument has high internal consistency, as well as convergent and discriminant validity. Findings from this study have indicated that the instrument can be used as a valid and reliable measure to examine the attitudes and beliefs of parents toward sexuality education in primary schools within Malaysia.
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Mohamad Khalil, Aref Ezrin, Hue San Kuay, Maruzairi Husain, and Yee Cheng Kueh. "Validation of the inventory of Callous-Unemotional Traits among school-going adolescents in Malaysia." PLOS ONE 18, no. 2 (February 16, 2023): e0276724. http://dx.doi.org/10.1371/journal.pone.0276724.
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A key component in the study of antisocial behaviour among adolescents is the presence of callous-unemotional (CU) traits. Among the established tools available to measure CU traits is the Inventory of Callous-Unemotional traits (ICU). To date, there is no validated questionnaire to assess CU traits for the local population. Therefore, there is a need to validate the Malay version of the ICU (M-ICU) so that research can be conducted to explore CU traits among adolescents in Malaysia. The aim of the study is to validate the M-ICU. Two phases of cross-sectional study involving 409 (phase 1 –exploratory factor analysis (EFA), n = 180; phase 2—confirmatory factor analysis (CFA), n = 229) adolescents aged between 13 to 18 years old were conducted from July until October 2020 at six secondary schools in Kuantan district. Participants were selected via multistage random sampling. The ICU was initially translated into Malay language using forward-backward translation procedure by a group of bilingual researchers. Study participants completed the final version of the M-ICU questionnaire and socio-demographic questionnaire. Data was analysed using SPSS version 26 and MPlus software for factor structure validity by performing EFA and CFA. Initial EFA revealed three factors with two items deleted. A further EFA with two factors resulted in the deletion of unemotional factor items. Cronbach’s alpha for overall scale improved from 0.70 to 0.74. CFA supported a two-factor solution with 17 items compared to the original English version that has three factors with 24 items. The findings revealed acceptable fit indices (RMSEA = 0.057, CFI = 0.941, TLI = 0.932, WRMR = 0.968). The study revealed that a two-factor model with 17 items of the M-ICU has good psychometric properties. The scale is valid and reliable to measure CU traits among adolescents in Malaysia.
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Debele, Taye, Firanbon Teshome, Demuma Amdisa, Girma Bacha, Zewdie Birhanu, and Yohannes Kebede. "A mixed-methods study on health learning materials utilization for COVID-19 risk communication and community engagement among health workers in Arsi Zone, Ethiopia: Implication for response to pandemic." PLOS ONE 17, no. 6 (June 7, 2022): e0269574. http://dx.doi.org/10.1371/journal.pone.0269574.
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Background Risk communication and community engagement are among the key strategies used in response to pandemics. Effective risk communication and community engagement can be achieved when assisted by health learning materials. However, their utilization was not known in Ethiopia. Therefore, the present study aimed to assess the utilization of COVID-19 health learning materials (HLMs), and explore barriers and facilitating factors. Methods A sequential explanatory mixed-methods study consisting of two phases was carried out. The first phase was a cross-sectional survey to assess the utilization of COVID-19 HLMs and their predictors. In this phase, a multistage sampling technique was used to select 530 health workers. A self-administered structured questionnaire was used for data collection. Epi-data manager version 4.6.0.2 and STATA version 16 were used for data entry and analyses, respectively. Descriptive analyses were carried out as necessary. Ordinal logistic regression analyses were done to identify the predictors of COVID-19 HLMs utilization. Phase two is a qualitative study to explore enablers and barriers to COVID-19 HLMs utilization. A judgmental sampling technique was used and 14 key informants were recruited. The collected data were uploaded into Atlas ti version 7.0.71. An inductive process of thematic analysis was employed and the data were coded, categorized, and thematized. Results Findings showed that out of the total 530 respondents, 210(39.6%), 117(22.1%), and 203(38.3%) of them never use COVID-19 HLMs, use sometimes, and always, respectively. Health workers’ perceived quality of COVID-19 HLMs [AOR = 6.44 (95% CI: 4.18–9.94)], health workers’ perceived usefulness of COVID-19 HLMs [AOR = 2.82 (95% CI: 1.88–4.22)], working facility [AOR = 1.83 (95% CI: 1.07–3.14)], educational level of the respondents [AOR = 1.73 (95% CI: 1.11–2.72)] and availability of COVID-19 HLMs [AOR = 1.45(95% CI: 1.01–2.08)] had statistically significant association with the utilization status of COVID-19 HLMs. Findings from the qualitative study showed that materials-related factors, and structure and health workers-related factors had influence on HLMs utilization. Conclusions In this study, we found that only a few of the respondents were regularly utilizing COVID-19 HLMs. Perceived quality, usefulness, and availability of HLMs, and health workers’ educational status and working facility determined the level of COVID-19 HLMs utilization. There is a need for giving due attention to HLMs, evaluating their quality, availing them to health facilities, and providing training for health workers.
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Azizi, Nemat, Mahmood Karimy, Rezvan Abedini, Bahram Armoon, and Ali Montazeri. "Development and Validation of the Health Literacy Scale for Workers." International Journal of Occupational and Environmental Medicine 10, no. 1 (January 30, 2019): 30–39. http://dx.doi.org/10.15171/ijoem.2019.1498.
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Background: Health literacy has received growing attention in recent years to reduce health disparities. Health literate individuals can gain access, understand and use health information to maintain, improve and promote good health. Objective: To develop and assess the psychometric properties of a tool for the measurement of health literacy among workers, the Health Literacy Scale for Workers (HELSW). Methods: 15 companies were selected from the factories of the industrial city of Saveh. 450 (400 male and 50 female) workers from Saveh, Iran, were selected through a multistage random sampling. The study had two stages—a qualitative and a quantitative stage. In the qualitative phase, the workers' beliefs were extracted based on 61 in-depth interviews. Content validity was assessed with the help of 12 experts in the field of health education, public health and occupational health. Also, face validity was evaluated through interviewing with 20 workers. In the quantitative phase, the reliability of the questionnaire was evaluated by measuring the internal consistency and test-retest reliability. The construct validity was assessed by the principal component analysis using varimax rotation. Results: In the exploratory factor analysis, six domains (ie, access, reading, understanding, assessment, decision making and applying health information, and self-efficacy) with 34 items were loaded; the model explained 64.3% of the total variance. Intraclass correlation coefficient and test-retest reliability ranged from 0.72 to 0.84 and 0.69 to 0.86, respectively. Conclusion: It seems that the developed Persian questionnaire, HELSW, is a reliable and valid measure of the health literacy in workers.
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Karami, Manoochehr, Salman Khazaei, Seyed Mohsen Zahraei, Talat Mokhtari Azad, Ali Zahiri, Ali Reza Moradi, Jalal Bathaei, Masoumeh Javaheri, and Jalaleddin Amiri. "Measles Outbreak in a Rural Population in Bahar District, Hamadan Province, West of Iran in 2018." Journal of Research in Health Sciences 20, no. 1 (February 27, 2020): e00470-e00470. http://dx.doi.org/10.34172/jrhs.2020.05.
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Background: Measles is in elimination phase in Iran. Following occurrence of two cases of measles in two children under six years old with the history of measles immunization in one of the villages affiliated to Bahar District, west of Hamadan Province, northwest of Iran, this study was conducted to determine the immunity status of people living in the village affected by the measles outbreak in spring of 2018. Study design: A cross-sectional (descriptive-analytical) study. Methods: Overall, 272 populations of 0-40 yr old in the village affected by outbreak were enrolled. Multistage sampling was used for choosing participants. The data collection tool was a researcher-made checklist used to collect epidemiological data including demographic characteristics and vaccination status. Blood samples were taken from them and sent to the measles reference laboratory for IgG testing. The amount of optical density (OD) greater than 0.2 was considered as positive and less than 0.1 negative, respectively. Results: The mean age of the study population was 17.4 ±11.8 yr and the sex ratio was almost the same. Levels of antibodies against measles were positive in 63.24%, intermediate in 12.5% and negative in 24.26%. There was no significant difference between the immunity status of the subjects with gender (P=0.236) and age group (P=0.113). Pearson correlation results showed that in males there was a significant positive correlation between the age of the participants and the serum IgG level (r = 0.26, P=0.003). Conclusion: Measles immunity in communities is not sufficient to prevent outbreaks and small epidemics, and it is recommended that periodically, serological assessments carried out at community level and especially at high-risk groups.
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Endyana, Cipta, FX Ari Agung Prastowo, Anwar Sani, Gemilang Lara Utama, and Prita Amalia. "GOVERNMENT POLICY AND REGULATION TO SUPPORT THE INTERNATIONAL TRADE OF MALUKU HIGH-GRADE NUTMEG COMMODITY IN SPATIAL PERSPECTIVE OVERVIEW." Humanities & Social Sciences Reviews 8, no. 4 (September 17, 2020): 1147–57. http://dx.doi.org/10.18510/hssr.2020.84109.
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Purpose: Based on World Trade Organization (WTO) Agreement, Indonesia had an obligation to conduct international trade based on the liberalization principle. The International Trade should conduct non-discrimination among member states, except there is a condition fulfilled under the general exception. One of the exceptions is about international standards related to Sanitary and Phytosanitary Measures. This article will elaborate on what extend Government policy and regulation should support international trade by complying with the international framework.
Methodology: The method used in this research is the Analytical Descriptive Survey Method. The data collection technique used is a phased sampling process (Multistage Stratified Random Sampling) by taking into account the complexity of the population gradually from the Population Cluster to the farmer stage. In the final determination of the farmers that will be sampled, two non-probability sampling schemes, Judgment Sampling, and Snowball Sampling are used.
Main Findings: Based on the search from secondary data, it was obtained that the development of nutmeg potential in Maluku, in its area, number of farmers, and production for five years (2012-2016) experienced fluctuations, in which it increased in 2016.
Implications/Applications: The development of the nutmeg industry in the Maluku Islands requires various programs aimed at improving the quality and productivity of nutmeg commodity so that it can ensure the continuity of supply chains and the sustainability of nutmeg industry development. Some of the programs are suggested after careful analysis of the data obtained.
Novelty/Originality: The combination of technical and social aspects is compiled within the Geographic Information System and spatially visualized, then can be classified comprehensively into a zone of nutmeg presence in the Maluku Islands. The Information of Nutmeg condition in several areas with spatial technique analysis is useful to the development of supporting infrastructure, capacity building of nutmeg farmer society, nutmeg industries, and Government Policy of Maluku Province to develop their nutmeg product.
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Kotwal, Atul, Tulika Seth, Rakesh Thakur, G. K. Rath, D. N. Sharma, and Jitendra Nagpal. "Outcome of community based planned intervention targeting perceptions, attitudes and health seeking behaviour regarding cancers in New Delhi, India." International Journal Of Community Medicine And Public Health 7, no. 2 (January 28, 2020): 711. http://dx.doi.org/10.18203/2394-6040.ijcmph20200454.
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Background: Cancer prevention and control needs to be based on effective implementation of all approaches. Community as well as individual level interventions to increase knowledge and early reporting have shown effectiveness. A community-based intervention trial was conducted to design, implement and test short-term outcomes of evidence based preventive strategies.Methods: A mixed methods, three phased study was conducted in three districts of Delhi, which were selected by a random process. Two randomly selected districts out of these three were intervention districts while third was the control. A total sample of 500 in each district was studied in quantitative pre and post -intervention phases. Multistage, stratified, cluster sampling was utilized. Pre-tested and validated tools were used.Results: Post intervention, statistically significant higher scores were observed in all domains in intervention districts as compared to control (p<0.01). Though comparison of slum versus non-slum showed significant increment in knowledge and practice scores, with higher scores for non-slum respondents, the attitudes were very similar (p>0.05). The increment score changes between males and females was similar in all classes of society versus control district. Comparison within the intervention and control groups revealed increased scores in intervention districts and decreased scores in control district, in all domains (p<0.05).Conclusions: Our study has helped in understanding the determinants of perceptions, attitude and practices regarding cancer in the community, This, helped in formulating the need-based intervention strategies. Testing the short-term outcome of intervention showed it to be effective.
Dissertations / Theses on the topic "Two phase multistage Sampling"
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Halbe, Chaitanya Vishwajit. "Effects of Two-Phase Flow in a Multistage Centrifugal Compressor." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/73305.
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The performance of a vapor compression system is known to be affected by the ingestion of liquid droplets in the compressor. In these multiphase flows, the liquid and the vapor phase are tightly coupled. Therefore the interphase heat, mass and momentum transfer as well as droplet dynamics including droplet breakup and droplet-wall interactions play a vital role in governing these flows. Only thermodynamic analyses or two-dimensional mean-line calculations are not sufficient to gain an in-depth understanding of the complex multiphase flow field within the compressor. The objective of this research was to extend the current understanding of the operation of a multistage centrifugal compressor under two-phase flow conditions, by performing three-dimensional computational analysis.
In this work, two-phase flow of a single constituent (refrigerant R134a) through a two-stage, in-line centrifugal compressor was analyzed using CFD. The CFD model accounted for real gas behavior of the vapor phase. Novel user defined routines were implemented to ensure accurate calculations of interphase heat, mass and momentum transfer terms and to model droplet impact on the compressor surfaces. An erosion model was developed and implemented to locate the erosion "hot spots" and to estimate the amount of material eroded.
To understand the effects of increasing liquid carryover, the mass flow rate of the liquid phase was increased from 1% to 5% of the vapor mass flow rate. The influence of droplet size on the compressor performance was assessed by varying the droplet diameter at the inlet from 100 microns to 400 microns. The results of the two-phase flow simulations were compared with the simulation involving only the vapor phase.
Liquid carryover altered the flow field within the compressor, and as a result, both impellers were observed to operate at off-design conditions. This effect was more pronounced for the second impeller. The overall effects of liquid carryover were detrimental to the compressor performance. The erosion calculations showed maximum erosion potential on the blade and shroud of the first impeller.
The results from this investigation provided new and useful information that can be used to support improved design solutions.Ph. D.
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Fiery, Michael Allen. "A form of two-phase sampling utilizing regression analysis." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4312.
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Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains iv, 81 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 32).
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Ninov, Valentin. "Two-dimensional zero-phase FIR filter design with nonuniform frequency sampling." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ43655.pdf.
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ZHU, GUOHUA. "ASCERTAINMENT IN TWO-PHASE SAMPLING DESIGNS FOR SEGREGATION AND LINKAGE ANALYSIS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1112844349.
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Zhu, Guohua. "Ascertainment in two-phase sampling designs for segregation and linkage analysis /." Connect to text online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1112844349.
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Thesis (Ph. D.)--Case Western Reserve University, 2005.[School of Medicine] Department of Epidemiology and Biostatistics. Includes bibliographical references. Available online via OhioLINK's ETD Center.
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Nan, Bin. "Information bounds and efficient estimates for two-phase designs with lifetime data /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/9587.
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Patel, Sonal. "Determination of Phase Equilibria and the Critical Point Using Two-Phase Molecular Dynamics Simulations with Monte Carlo Sampling." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3587.
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The two-phase MD technique employed in this work determines the liquid and vapor phase densities from a histogram of molecular densities within phase clusters in the simulation cell using a new Monte Carlo (MC) sampling method. These equilibrium densities are then fitted in conjunction with known critical-point scaling laws to obtain the critical temperature, and the critical density. This MC post-processing method was found to be more easily implemented in code, and it is efficient and easily applied to complex, structured molecules. This method has been successfully applied and benchmarked for a simple Lennard-Jones (LJ) fluid and a structured molecule, propane. Various degrees of internal flexibility in the propane models showed little effect on the coexisting densities far from critical point, but internal flexibility (angle bending and bond vibrations) seemed to affect the saturated liquid densities in the near-critical region, changing the critical temperature by approximately 20 K. Shorter cutoffs were also found to affect the phase dome and the location of the critical point. The developed MD+MC method was then used to test the efficacy of two all-atom, site-site pair potential models (with and without point charges) developed solely from the energy landscape obtained from high-level ab initio pair interactions for the first time. Both models produced equivalent phase domes and critical loci. The model's critical temperature for methanol is 77 K too high while that for 1-propanol is 80 K too low, but the critical densities are in good agreement. These differences are likely attributable to the lack of multi-body interactions in the true pair potential models used here. Lastly, the transferability of the ab initio potential model was evaluated by applying it to 1-pentanol. An attempt has been made to separate the errors due to transferability of the potential model from errors due to the use of a true-pair potential. The results suggested a good level of transferability for the site-site model. The lack of multi-body effects appears to be dominant weakness in using the generalized ab initio potential model for determination of the phase dome and critical properties of larger alcohols.
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Chatterjee, Nilanjan. "Semiparametric inference based on estimating equations in regression models for two phase outcome dependent sampling /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/8959.
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Ning, Shuluo. "Bayesian Degradation Analysis Considering Competing Risks and Residual-Life Prediction for Two-Phase Degradation." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1339559200.
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Camci, Gulden. "Application Of Isokinetic Sampling Technique For Local Solid Densities In Upward Liquid-solid Flows Through An Annulus." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1089796/index.pdf.
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In this study, radial solid density distributions in upward flowing water-feldspar mixtures through a concentric annulus were investigated. Local solid density measurements were performed at a test cross-section in the fully developed flow region of a concentric annulus, which is a part of a closed-loop system consisting of a head tank, a variable speed slurry pump, an orificemeter, a heat exchanger, an annulus, a temperature probe, and a drain line. The solid particles with mean diameters of 72 and 138 
m at two different feed solid concentrations of 1 and 2 % v/v were used in the prepared slurries. The dependent variables being local solid density, local mixture velocity, and axial frictional pressure drop along the test-section, an experimental work was performed to obtain the radial solid density profiles and axial pressure gradients at different operating conditions. To determine the local solid densities, a sampling probe was used. At the beginning, this probe was used as a pitot tube to measure the local velocities in the test cross-section. Making use of these data, local solid densities were measured with the same probe under isokinetic and nonisokinetic conditions to compare both. For this purpose, an isokinetic sampling unit was designed and constructed to withdraw the samples under isokinetic flow conditions, at which the sampling velocity in the probe equated to the true flow velocity in the annulus very closely. The required constant back-pressure was supplied by pressurized N2 gas to equate these velocities to each other. The amounts of solids in the slurry samples collected at seven different radial locations in the test area under isokinetic and non-isokinetic conditions were determined by the gravimetric method. Local solid densities showed more uniform trends at the feed solid concentration of 1% v/v than those at 2% v/v. Increasing the feed solid concentration and particle size changed the shape of these profiles. The obtained local solid densities were generally higher near the outer wall than those near the inner wall
this result was consistent with the literature. As a general trend, local solid densities showed a decreasing trend at around a dimensionless radial distance of &
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=0.4, where the slurry velocity profile had its maximum value. It was observed that the two-phase axial frictional pressure gradients along the test section in the fully developed flow region increased with increasing feed solid concentration and the particle size at a constant slurry flow rate. Isokinetic sampling results showed that the local solid densities increased consistently with the increasing slurry velocity at all radial distances in the annular gap, while this trend was not observed clearly in the non-isokinetic measurements. Also the variations of the local solid densities along the radial distance were more obvious in the isokinetic results while these variations were obscured under nonisokinetic conditions by the experimental error at a higher level.
Books on the topic "Two phase multistage Sampling"
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Andersson, Claes. On the use of two-phase sampling in estimation of parameters in domains where data contain misclassification and measurement errors. Uppsala: Uppsala University, 1994.
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Hankin, David, Michael S. Mohr, and Kenneth B. Newman. Sampling Theory. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198815792.001.0001.
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We present a rigorous but understandable introduction to the field of sampling theory for ecologists and natural resource scientists. Sampling theory concerns itself with development of procedures for random selection of a subset of units, a sample, from a larger finite population, and with how to best use sample data to make scientifically and statistically sound inferences about the population as a whole. The inferences fall into two broad categories: (a) estimation of simple descriptive population parameters, such as means, totals, or proportions, for variables of interest, and (b) estimation of uncertainty associated with estimated parameter values. Although the targets of estimation are few and simple, estimates of means, totals, or proportions see important and often controversial uses in management of natural resources and in fundamental ecological research, but few ecologists or natural resource scientists have formal training in sampling theory. We emphasize the classical design-based approach to sampling in which variable values associated with units are regarded as fixed and uncertainty of estimation arises via various randomization strategies that may be used to select samples. In addition to covering standard topics such as simple random, systematic, cluster, unequal probability (stressing the generality of Horvitz–Thompson estimation), multi-stage, and multi-phase sampling, we also consider adaptive sampling, spatially balanced sampling, and sampling through time, three areas of special importance for ecologists and natural resource scientists. The text is directed to undergraduate seniors, graduate students, and practicing professionals. Problems emphasize application of the theory and R programming in ecological and natural resource settings.
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Pezo-Lanfranco, Luis Nicanor. Bioarqueologia e Antropologia Forense: Métodos de escavação, recuperação e curadoria de ossos humanos. Brazil Publishing, 2021. http://dx.doi.org/10.31012/978-65-5861-376-3.
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This book presents a synthesis on the necessary methods and techniques for the correct excavation, recovery and conservation of human remains, as well as notions of sampling and analysis of bones, useful for an adequate study of funeral contexts in conventional (bio)archaeological research or forensic-anthropology. As this book was written primarily for archeology students and archeologists with little training in bone handling, the language is easy-to-follow. The book is divided into two sections that roughly correspond to the two phases in which the method of analysis of human bones can be divided. In the first section, we describe the Phase I or field work that includes recovery methods, from the prospection and identification of burial sites, excavation and recording, field-sampling techniques, to the packaging and transport of bones to the laboratory. In the second part of the book, Phase II or laboratory work, we describe the treatment that should be given to bones from their arrival to laboratory of analysis to the final storage. In this section, we show the methods of cleaning and preparation of bones for further analysis, some basic notions on restoration and conservation, and relevant information about sampling techniques and their scientific principles to obtain information from the examined individual. Along the text we emphasize the informative potential of each analysis from the bioarchaeological and anthropological-forensic viewpoint.
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Chalabi, Azadeh. A Cross-Case Analysis of NHRAPs of Fifty-Three Countries. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198822844.003.0006.
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Part III, ‘Empirical Perspectives’, contains only one chapter, Chapter 5, which presents the results of a cross-case analysis of national human rights action plans of fifty-three countries. Adopting a purposive sampling technique, these countries are selected on the basis of four main criteria, namely human rights record, geographical diversity, political regimes, and cultural diversity. This comprehensive cross-case study follows two objectives. The first objective of this chapter is to unearth significant problems in the ‘pre-phase’ and the four phases of planning, namely ‘preparatory phase’, ‘development phase’, ‘implementing phase’, and ‘assessment phase’. These problems are significantly detrimental to the effective implementation of human rights and their identification will substantially help generate response strategies. These are best addressed by attempting to mitigate their root causes as opposed to only correcting the immediately obvious symptoms. This brings us to the chapter’s second objective, which is to explore the underlying causes of these problems.
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Fox, Raymond. The Use of Self. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780190616144.001.0001.
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This monograph presents recent advances in neural network (NN) approaches and applications to chemical reaction dynamics. Topics covered include: (i) the development of ab initio potential-energy surfaces (PES) for complex multichannel systems using modified novelty sampling and feedforward NNs; (ii) methods for sampling the configuration space of critical importance, such as trajectory and novelty sampling methods and gradient fitting methods; (iii) parametrization of interatomic potential functions using a genetic algorithm accelerated with a NN; (iv) parametrization of analytic interatomic potential functions using NNs; (v) self-starting methods for obtaining analytic PES from ab inito electronic structure calculations using direct dynamics; (vi) development of a novel method, namely, combined function derivative approximation (CFDA) for simultaneous fitting of a PES and its corresponding force fields using feedforward neural networks; (vii) development of generalized PES using many-body expansions, NNs, and moiety energy approximations; (viii) NN methods for data analysis, reaction probabilities, and statistical error reduction in chemical reaction dynamics; (ix) accurate prediction of higher-level electronic structure energies (e.g. MP4 or higher) for large databases using NNs, lower-level (Hartree-Fock) energies, and small subsets of the higher-energy database; and finally (x) illustrative examples of NN applications to chemical reaction dynamics of increasing complexity starting from simple near equilibrium structures (vibrational state studies) to more complex non-adiabatic reactions. The monograph is prepared by an interdisciplinary group of researchers working as a team for nearly two decades at Oklahoma State University, Stillwater, OK with expertise in gas phase reaction dynamics; neural networks; various aspects of MD and Monte Carlo (MC) simulations of nanometric cutting, tribology, and material properties at nanoscale; scaling laws from atomistic to continuum; and neural networks applications to chemical reaction dynamics. It is anticipated that this emerging field of NN in chemical reaction dynamics will play an increasingly important role in MD, MC, and quantum mechanical studies in the years to come.
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Raff, Lionel, Ranga Komanduri, Martin Hagan, and Satish Bukkapatnam. Neural Networks in Chemical Reaction Dynamics. Oxford University Press, 2012. http://dx.doi.org/10.1093/oso/9780199765652.001.0001.
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This monograph presents recent advances in neural network (NN) approaches and applications to chemical reaction dynamics. Topics covered include: (i) the development of ab initio potential-energy surfaces (PES) for complex multichannel systems using modified novelty sampling and feedforward NNs; (ii) methods for sampling the configuration space of critical importance, such as trajectory and novelty sampling methods and gradient fitting methods; (iii) parametrization of interatomic potential functions using a genetic algorithm accelerated with a NN; (iv) parametrization of analytic interatomic potential functions using NNs; (v) self-starting methods for obtaining analytic PES from ab inito electronic structure calculations using direct dynamics; (vi) development of a novel method, namely, combined function derivative approximation (CFDA) for simultaneous fitting of a PES and its corresponding force fields using feedforward neural networks; (vii) development of generalized PES using many-body expansions, NNs, and moiety energy approximations; (viii) NN methods for data analysis, reaction probabilities, and statistical error reduction in chemical reaction dynamics; (ix) accurate prediction of higher-level electronic structure energies (e.g. MP4 or higher) for large databases using NNs, lower-level (Hartree-Fock) energies, and small subsets of the higher-energy database; and finally (x) illustrative examples of NN applications to chemical reaction dynamics of increasing complexity starting from simple near equilibrium structures (vibrational state studies) to more complex non-adiabatic reactions. The monograph is prepared by an interdisciplinary group of researchers working as a team for nearly two decades at Oklahoma State University, Stillwater, OK with expertise in gas phase reaction dynamics; neural networks; various aspects of MD and Monte Carlo (MC) simulations of nanometric cutting, tribology, and material properties at nanoscale; scaling laws from atomistic to continuum; and neural networks applications to chemical reaction dynamics. It is anticipated that this emerging field of NN in chemical reaction dynamics will play an increasingly important role in MD, MC, and quantum mechanical studies in the years to come.
Book chapters on the topic "Two phase multistage Sampling"
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Lohr, Sharon L. "Two-Phase Sampling." In Sampling, 457–82. 3rd ed. Boca Raton: Chapman and Hall/CRC, 2021. http://dx.doi.org/10.1201/9780429298899-12.
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Singh, Ravindra, and Naurang Singh Mangat. "Two-Phase Sampling." In Kluwer Texts in the Mathematical Sciences, 221–47. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-017-1404-4_9.
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Särndal, Carl-Erik, Bengt Swensson, and Jan Wretman. "Two-Phase Sampling." In Model Assisted Survey Sampling, 343–85. New York, NY: Springer New York, 1992. http://dx.doi.org/10.1007/978-1-4612-4378-6_9.
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Stamp, Mark. "Two-phase random sampling." In Introduction to Machine Learning with Applications in Information Security, 201–10. 2nd ed. Boca Raton: Chapman and Hall/CRC, 2022. http://dx.doi.org/10.1201/9781003264873-11.
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Brus, Dick J. "Two-phase random sampling." In Spatial Sampling with R, 201–10. Boca Raton: Chapman and Hall/CRC, 2022. http://dx.doi.org/10.1201/9781003258940-11.
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de Vries, Pieter G. "Two-Phase Sampling or Double Sampling." In Sampling Theory for Forest Inventory, 104–40. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71581-5_6.
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Fattorini, L. "A Two-Phase Sampling Strategy for Forest Inventories." In Advances in Forest Inventory for Sustainable Forest Management and Biodiversity Monitoring, 143–56. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0649-0_12.
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Kane, Birane. "Multistage Preconditioning for Adaptive Discretization of Porous Media Two-Phase Flow." In Lecture Notes in Computational Science and Engineering, 573–81. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-55874-1_56.
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Jerez, Danko J., Hector A. Jensen, and Michael Beer. "A Two-Phase Sampling Approach for Reliability-Based Optimization in Structural Engineering." In Springer Series in Reliability Engineering, 21–48. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-28859-3_2.
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Borrás, Esther, Hartmut Herrmann, Markus Kalberer, Amalia Muñoz, Anke Mutzel, Teresa Vera, and John Wenger. "Sampling for Offline Analysis." In A Practical Guide to Atmospheric Simulation Chambers, 207–40. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-22277-1_6.
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AbstractThe detailed chemical characterization of gas and particle phase species is essential for interpreting the results of atmospheric simulation chamber experiments. Although the application of online techniques has advanced significantly over the last two decades, offline analytical methods such as GC–MS and LC–MS are still frequently used. In this chapter, the approaches commonly employed for gas and particle sampling prior to subsequent offline analysis are described in detail. Methods involving the use of cartridges, canisters, bags and sorbent tubes for gas sampling are described with the support of examples reported in the literature. Technical descriptions related to the application of different types of filters, inertial classifiers and particle-into-liquid samplers for the collection of particles are also provided.
Conference papers on the topic "Two phase multistage Sampling"
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Jalali, Zeinab S., Alireza Rezvanian, and Mohammad Reza Meybodi. "A two-phase sampling algorithm for social networks." In 2015 2nd International Conference on Knowledge-Based Engineering and Innovation (KBEI). IEEE, 2015. http://dx.doi.org/10.1109/kbei.2015.7436212.
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Guanghui Liu, Weidong Cao, Yue Li, Dangxiong Wang, and Bing Liu. "Study on solid-liquid two-phase unsteady flow in multistage pump." In 2014 ISFMFE - 6th International Symposium on Fluid Machinery and Fluid Engineering. Institution of Engineering and Technology, 2014. http://dx.doi.org/10.1049/cp.2014.1244.
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Singh, G. N., D. Majhi, and S. Prasad. "Estimation of population mean in two-phase successive sampling." In 2012 1st International Conference on Recent Advances in Information Technology (RAIT). IEEE, 2012. http://dx.doi.org/10.1109/rait.2012.6194538.
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Derammelaere, S., L. Carlier, B. Vervisch, C. Debruyne, K. Stockman, P. Cox, L. Vandevelde, and G. Van den Abeele. "The opportunities of two-phase hybrid stepping motor back EMF sampling." In 2011 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE, 2011. http://dx.doi.org/10.1109/ecce.2011.6063752.
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Chen, Bin, Peter Haas, and Peter Scheuermann. "A new two-phase sampling based algorithm for discovering association rules." In the eighth ACM SIGKDD international conference. New York, New York, USA: ACM Press, 2002. http://dx.doi.org/10.1145/775047.775114.
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Hedley, Y. L., M. Younas, A. James, and M. Sanderson. "A two-phase sampling technique for information extraction from hidden web databases." In the 6th annual ACM international workshop. New York, New York, USA: ACM Press, 2004. http://dx.doi.org/10.1145/1031453.1031456.
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Roy, Aishworya, and Arnab Ghosh. "Multistage Feedback Control of a PV Supplied Two Phase Interleaved Boost Converter for Grid Interfacing Applications." In 2021 4th Biennial International Conference on Nascent Technologies in Engineering (ICNTE). IEEE, 2021. http://dx.doi.org/10.1109/icnte51185.2021.9487727.
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Jarrett, Jerome P., and Tiziano Ghisu. "Balancing Configuration and Refinement in the Design of Two-Spool Multistage Compression Systems." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26371.
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Despite many advances in both optimization methods and computational fluid dynamics, the timely automatic selection and refinement, via physics-based and empirical methods, of “optimal” configurations of compression systems remains challenging. This is due, in part, to the large number of design parameters (with associated high computational cost) operating over wide ranges that can be non-smooth, if not discontinuous (to which many optimization algorithms, developed for smooth problems, are ill-suited). It is further complicated by the phasic nature of turbomachinery design and the associated need to balance the amount of time and computational resource devoted to selecting the most promising configurations with that expended in their refinement. This paper compares a number of combinations of a multi-fidelity approach for configuration selection with a high-fidelity method for design refinement. The system is tested on the aerodynamic design of a complete two-spool core compression system for a generic high bypass ratio turbofan. The resulting designs are obliged to meet familiar constraints for overall design point pressure rise and surge margin together with a number of mechanical constraints including maximum shaft speeds. Through the configuration phase, the number of stages and the duty split between the spools are permitted to change. It is shown that the performance of the design refinement phase is only a weak function of the preceding configuration phase provided that the latter is well into diminishing returns with respect to approaching a converged solution. It is hence shown possible to obtain equally good designs in around half the computational run-time by exploiting this weak dependence by effectively decoupling the configuration and refinement phases and starting the latter before the former has apparently finished. It is also shown that if either configuration or refinement is allowed to dominate the design process, inferior designs result. The best designs are associated with between half and three-quarters of the design effort being devoted to configuration selection.
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Bolla, Venkateswara Rao, Swathi Amancha, and T. Venu Gopal. "A two phase copyright protection scheme for digital images using visual cryptography and sampling methods." In 2016 International Conference on Electrical, Electronics, and Optimization Techniques (ICEEOT). IEEE, 2016. http://dx.doi.org/10.1109/iceeot.2016.7755046.
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Ri, Shien, and Hiroshi Tsuda. "Two-dimensional sampling moiré method for fast and accurate phase analysis of single fringe pattern." In International Conference on Optics in Precision Engineering and Nanotechnology (icOPEN2013), edited by Chenggen Quan, Kemao Qian, and Anand Asundi. SPIE, 2013. http://dx.doi.org/10.1117/12.2018979.
Full textReports on the topic "Two phase multistage Sampling"
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Smith, R. C. 105-N basin sediment disposition phase-two sampling and analysis plan. Office of Scientific and Technical Information (OSTI), March 1997. http://dx.doi.org/10.2172/16071.
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Kelner, Britton, and Sparks. L51986 Natural Gas Sample Collection and Handling Phase II Simulated Field Conditions. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), January 2003. http://dx.doi.org/10.55274/r0011157.
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Phase II was originally planned as a series of field tests to confirm the results of the sampling methods performance tests conducted during Phase I. However, the API Chapter 14.1 Gas Sampling Research Working Group chose to have the tests conducted at a newly developed wet gas test facility located at the Colorado Engineering Experiment Station (CEESI), in Nunn, Colorado. Three general tests were conducted. Test Plan I was intended to investigate the effects of sample point location on on-line gas chromatograph (GC) analyses and on spot sampling methods. Test Plan II was intended to investigate the effects of sample point location on on-line GC analyses and to compare several spot sampling methods when sampling from the same point. Test Plan III was intended to investigate the effects of coupling configurations and cylinder temperature on two specific methods: Helium Pop, and purging - Fill/Empty.
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George, Grant, and Hawley. PR-015-13611-R01 Evaluation of Selected Sampling Techniques on Hydrocarbon-Wet Gas Streams. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), December 2014. http://dx.doi.org/10.55274/r0010403.
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This project evaluated selected single-phase gas sampling methods as candidates for use in sampling hydrocarbon-wet gas streams and obtaining representative samples of only the gas phase, rather than samples of both the gas and liquid. Two spot sampling methods, the helium �pop� method and the floating piston cylinder method, were chosen for evaluation. To capture samples of only the gas phase required one or more arrangements for separating liquids from the sample stream. To this end, a coalescing filter and a vortex separator were chosen for testing with the two sampling methods. The various sampling approaches were tested using the Sampling Method Performance Verification Procedure of API MPMS Chapter 14.1, Appendix F, adapted as appropriate for use in hydrocarbon-wet gas streams. Preliminary tests at SwRI�s Metering Research Facility (MRF) were used to identify possible problems with the equipment and sampling procedures, so that the equipment and procedures could be corrected before the formal tests were conducted. The formal tests were performed at a field site carrying a hydrocarbon-wet gas stream from a shale formation. Results of the formal tests produced recommendations to improve the general ability of the chosen wet-gas sampling method to capture accurate samples of the gas phase, as well as recommended changes to the API Sampling Verification Procedure for testing wet-gas sampling methods.
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George and Grant. PR-015-14609-R01 Study of Sample Probe Minimum Insertion Depth Requirements. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), May 2015. http://dx.doi.org/10.55274/r0010844.
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Probes for natural gas sample collection and analysis must extend far enough into the pipeline to avoid contaminants at the pipe wall, but must not be so long that there is a risk of flow-induced resonant vibration and failure. PRCI has sponsored a project to determine the minimum probe depth for obtaining a representative single-phase gas sample in flows with small amounts of contaminants. To this end, Phase 1 of the project involved a review of existing literature and industry standards to identify key probe design parameters. Several current standards for sampling clean, dry natural gas were reviewed, and their requirements for sample probe dimensions and mounting arrangements were compared. Some of these standard requirements suggested probe designs and sampling approaches that could be used to collect gas-only samples from two-phase flows. A literature review identified many useful studies of two-phase flows and phase behavior. While few of these studies evaluated probe designs, the majority examined the behavior of gas and liquid in two-phase flows, methods of predicting flow regimes, and methods of predicting flow conditions that define the minimum probe depth for gas-only samples in gas-liquid flows. Useful recommendations were provided for selecting general probe features where liquids must be rejected from the gas sample. A basic design procedure was also provided to select the minimum sample probe insertion length and optimum installation position for known flow conditions. Plans to test the recommendations and the design procedure in Phase 2 of the project were also discussed. This report has a related webinar.
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Shiihi, Solomon, U. G. Okafor, Zita Ekeocha, Stephen Robert Byrn, and Kari L. Clase. Improving the Outcome of GMP Inspections by Improving Proficiency of Inspectors through Consistent GMP Trainings. Purdue University, November 2021. http://dx.doi.org/10.5703/1288284317433.
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Approximately 90% of the pharmaceutical inspectors in a pharmacy practice regulatory agency in West Africa have not updated their training on Good Manufacturing Practice (GMP) inspection in at least eight years. However, in the last two years the inspectors relied on learning-on-the job skills. During this time, the agency introduced about 17% of its inspectors to hands-on GMP trainings. GMP is the part of quality assurance that ensures the production or manufacture of medicinal products is consistent in order to control the quality standards appropriate for their intended use as required by the specification of the product. Inspection reports on the Agency’s GMP inspection format in-between 2013 to 2019 across the six geopolitical zones in the country were reviewed retrospectively for gap analysis. Sampling was done in two phases. During the first phase sampling of reports was done by random selection, using a stratified sampling method. In the second phase, inspectors from the Regulatory Agency from different regions were contacted on phone to send in four reports each by email. For those that forwarded four reports, two, were selected. However for those who forwarded one or two, all were considered. Also, the Agency’s inspection format/checklist was compared with the World Health Organization (WHO) GMP checklist and the GMP practice observed. The purpose of this study was to evaluate the reporting skills and the ability of inspectors to interpret findings vis-à-vis their proficiency in inspection activities hence the efficiency of the system. Secondly, the study seeks to establish shortfalls or adequacies of the Agency’s checklist with the aim of reviewing and improving in-line with best global practices. It was observed that different inspectors have different styles and methods of writing reports from the same check-list/inspection format, leading to non-conformances. Interpretations of findings were found to be subjective. However, it was also observed that inspection reports from the few inspectors with the hands-on training in the last two year were more coherent. This indicates that pharmaceutical inspectors need to be trained regularly to increase their knowledge and skills in order to be kept on the same pace. It was also observed that there is a slight deviation in placing sub indicators under the GMP components in the Agency’s GMP inspection format, as compared to the WHO checklist.
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Beauregard, Yannick. PR261-193604-R01 Optimizing Stress Corrosion Cracking Management - Field and Economic Study. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), October 2021. http://dx.doi.org/10.55274/r0012179.
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This work aims to improve pipeline segment prioritization for stress corrosion cracking (SCC) excavations. Specifically, it is aimed at optimizing the technical accuracy and the cost of the Association for Materials Protection and Performance (AMPP, formerly NACE) Stress Corrosion Cracking Direct Assessment (SP0204-2015) process by: - evaluating the SCC susceptibility criteria of soil property parameters that were proposed in the first phase of the project (pH, resistivity, sulfide concentration, soil carbon dioxide (CO2) concentration, carbonate concentration, soil oxygen (O2) concentration, sulphate reducing bacteria (SRB) concentration, oxygen reduction potential (ORP), soil moisture content, soil effect on steel hydrogen permeation and electrochemical properties) - investigating the technical and economic feasibility of using commercially available field instruments for the measurement of these soil parameters to overcome limitations of laboratory testing (e.g., sample preservation and external costs) Soil sampling and testing was conducted at twenty-two dig sites in three geographic regions in the USA and Canada. On-site soil sampling and testing activities were conducted by field service providers using commercially available portable instruments. Soil samples were sent to laboratories for chemical analysis and for electrochemical characterization. The data analysis consisted of: (i) comparison of soil properties obtained at sites with and without SCC against the proposed SCC susceptibility criteria (ii) comparison of soil property data obtained in the field to those obtained through laboratory analysis (iii) comparison of soil property data obtained using different field and lab measurement techniques (iv) comparison of costs associated with performing in-field measurements to those of laboratory analysis.
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Bowlin, Elizabeth, and Puneet Agarwal. PR-201-153718-R03 Integrity Assessment of DTI Pipelines Using High Resolution NDE in Select Areas. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), May 2018. http://dx.doi.org/10.55274/r0011486.
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Hydrostatic test and In-Line Inspection are the prescribed integrity assessment methods cited in various Codes and Regulations and have been proven to enhance pipeline safety. But a significant number of pipelines across the world remain difficult to inspect and impractical to modify for inspection by the prescribed methods due to physical configurations or operating conditions. This research performs a state of the art (SOTA) analysis of NDE technology readiness considering physical and operational barriers and technology deployment from inside, outside or over pipelines, and the possible role of inspection sampling to conclude pipeline integrity and justify intervals for conversion for piggability or hydrotest. The goal of the research is to propose alternatives to ILI for safe prioritization and scheduling for conversion or replacement and not to replace hydrostatic test or ILI as currently prescribed in Codes and Regulations. The scope of the research is limited to technologies and integrity management concerning metal loss threat. This report represents the third and final update of prior reports from the two preceding years presenting a compendium of technologies describing technology readiness for state of the art non-destructive evaluation (NDE) technologies intended for low resolution pipeline condition screening and high resolution NDE for deployment at sample locations with capabilities applicable to difficult to inspect pipeline configurations. Integrated cleaning and inspection pigs, smart balls, external deployed ultrasonic, radiographic and magnetometry are pipe wall screening technologies evaluated in the reports. A structured process is proposed for assessing pipeline integrity based on low resolution screening of the full length of a pipeline segment followed by high resolution NDE samples at locations where screening indicates locations of possible wall loss. The process employs extreme value analysis for prediction of maximum metal loss severity across the screened segment. For instances where no metal loss indications reported by screening or from high resolution samples an alternative "compliance approach" is also addressed. Case studies are presented where PRCI members have deployed some of the technologies referenced in the NDE SOTA phase of the research and implemented the proposed extreme value or the compliance approaches. Validation of fitness for service conclusions based on inspection sampling by comparison with full length high resolution ILI or hydrostatic test are included in some of the case studies. The conclusions of the case studies demonstrate integrity conclusions obtained from the PRCI structured process are conservative and consistent with ILI or hydrostatic test conclusions. Based on the experience from the case studies and the SOTA, a metal loss screening efficiency factor (MLSE) is proposed enabling pipeline operators to understand the general relationship between screening level (sample stratification) and direct examination (inspection sampling) required to provide equivalent understanding of pipe wall condition, limited to metal loss. As mentioned by ASME/API ILI has limitations that need to be considered in its deployment and full discovery of metal loss conditions. Under some conditions (noted by API 1163) ILI predictions can be accepted without any direct examinations or verifications, i.e full length screening (high resolution) and no verification samples. At the other end of the spectrum random sampling can be theoretically deployed as a screening approach but depending on the condition of the pipeline, the high-resolution sample area could be very large to obtain a significant integrity conclusion. This report proposes a comparative scale of effectiveness for SOTA pipe wall screening technologies that offer the operator an expectation of high resolution NDE sample size. There is a related webinar
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Delwiche, Michael, Boaz Zion, Robert BonDurant, Judith Rishpon, Ephraim Maltz, and Miriam Rosenberg. Biosensors for On-Line Measurement of Reproductive Hormones and Milk Proteins to Improve Dairy Herd Management. United States Department of Agriculture, February 2001. http://dx.doi.org/10.32747/2001.7573998.bard.
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The original objectives of this research project were to: (1) develop immunoassays, photometric sensors, and electrochemical sensors for real-time measurement of progesterone and estradiol in milk, (2) develop biosensors for measurement of caseins in milk, and (3) integrate and adapt these sensor technologies to create an automated electronic sensing system for operation in dairy parlors during milking. The overall direction of research was not changed, although the work was expanded to include other milk components such as urea and lactose. A second generation biosensor for on-line measurement of bovine progesterone was designed and tested. Anti-progesterone antibody was coated on small disks of nitrocellulose membrane, which were inserted in the reaction chamber prior to testing, and a real-time assay was developed. The biosensor was designed using micropumps and valves under computer control, and assayed fluid volumes on the order of 1 ml. An automated sampler was designed to draw a test volume of milk from the long milk tube using a 4-way pinch valve. The system could execute a measurement cycle in about 10 min. Progesterone could be measured at concentrations low enough to distinguish luteal-phase from follicular-phase cows. The potential of the sensor to detect actual ovulatory events was compared with standard methods of estrus detection, including human observation and an activity monitor. The biosensor correctly identified all ovulatory events during its testperiod, but the variability at low progesterone concentrations triggered some false positives. Direct on-line measurement and intelligent interpretation of reproductive hormone profiles offers the potential for substantial improvement in reproductive management. A simple potentiometric method for measurement of milk protein was developed and tested. The method was based on the fact that proteins bind iodine. When proteins are added to a solution of the redox couple iodine/iodide (I-I2), the concentration of free iodine is changed and, as a consequence, the potential between two electrodes immersed in the solution is changed. The method worked well with analytical casein solutions and accurately measured concentrations of analytical caseins added to fresh milk. When tested with actual milk samples, the correlation between the sensor readings and the reference lab results (of both total proteins and casein content) was inferior to that of analytical casein. A number of different technologies were explored for the analysis of milk urea, and a manometric technique was selected for the final design. In the new sensor, urea in the sample was hydrolyzed to ammonium and carbonate by the enzyme urease, and subsequent shaking of the sample with citric acid in a sealed cell allowed urea to be estimated as a change in partial pressure of carbon dioxide. The pressure change in the cell was measured with a miniature piezoresistive pressure sensor, and effects of background dissolved gases and vapor pressures were corrected for by repeating the measurement of pressure developed in the sample without the addition of urease. Results were accurate in the physiological range of milk, the assay was faster than the typical milking period, and no toxic reagents were required. A sampling device was designed and built to passively draw milk from the long milk tube in the parlor. An electrochemical sensor for lactose was developed starting with a three-cascaded-enzyme sensor, evolving into two enzymes and CO2[Fe (CN)6] as a mediator, and then into a microflow injection system using poly-osmium modified screen-printed electrodes. The sensor was designed to serve multiple milking positions, using a manifold valve, a sampling valve, and two pumps. Disposable screen-printed electrodes with enzymatic membranes were used. The sensor was optimized for electrode coating components, flow rate, pH, and sample size, and the results correlated well (r2= 0.967) with known lactose concentrations.
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Anderson, Gerald L., and Kalman Peleg. Precision Cropping by Remotely Sensed Prorotype Plots and Calibration in the Complex Domain. United States Department of Agriculture, December 2002. http://dx.doi.org/10.32747/2002.7585193.bard.
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This research report describes a methodology whereby multi-spectral and hyperspectral imagery from remote sensing, is used for deriving predicted field maps of selected plant growth attributes which are required for precision cropping. A major task in precision cropping is to establish areas of the field that differ from the rest of the field and share a common characteristic. Yield distribution f maps can be prepared by yield monitors, which are available for some harvester types. Other field attributes of interest in precision cropping, e.g. soil properties, leaf Nitrate, biomass etc. are obtained by manual sampling of the filed in a grid pattern. Maps of various field attributes are then prepared from these samples by the "Inverse Distance" interpolation method or by Kriging. An improved interpolation method was developed which is based on minimizing the overall curvature of the resulting map. Such maps are the ground truth reference, used for training the algorithm that generates the predicted field maps from remote sensing imagery. Both the reference and the predicted maps are stratified into "Prototype Plots", e.g. 15xl5 blocks of 2m pixels whereby the block size is 30x30m. This averaging reduces the datasets to manageable size and significantly improves the typically poor repeatability of remote sensing imaging systems. In the first two years of the project we used the Normalized Difference Vegetation Index (NDVI), for generating predicted yield maps of sugar beets and com. The NDVI was computed from image cubes of three spectral bands, generated by an optically filtered three camera video imaging system. A two dimensional FFT based regression model Y=f(X), was used wherein Y was the reference map and X=NDVI was the predictor. The FFT regression method applies the "Wavelet Based", "Pixel Block" and "Image Rotation" transforms to the reference and remote images, prior to the Fast - Fourier Transform (FFT) Regression method with the "Phase Lock" option. A complex domain based map Yfft is derived by least squares minimization between the amplitude matrices of X and Y, via the 2D FFT. For one time predictions, the phase matrix of Y is combined with the amplitude matrix ofYfft, whereby an improved predicted map Yplock is formed. Usually, the residuals of Y plock versus Y are about half of the values of Yfft versus Y. For long term predictions, the phase matrix of a "field mask" is combined with the amplitude matrices of the reference image Y and the predicted image Yfft. The field mask is a binary image of a pre-selected region of interest in X and Y. The resultant maps Ypref and Ypred aremodified versions of Y and Yfft respectively. The residuals of Ypred versus Ypref are even lower than the residuals of Yplock versus Y. The maps, Ypref and Ypred represent a close consensus of two independent imaging methods which "view" the same target. In the last two years of the project our remote sensing capability was expanded by addition of a CASI II airborne hyperspectral imaging system and an ASD hyperspectral radiometer. Unfortunately, the cross-noice and poor repeatability problem we had in multi-spectral imaging was exasperated in hyperspectral imaging. We have been able to overcome this problem by over-flying each field twice in rapid succession and developing the Repeatability Index (RI). The RI quantifies the repeatability of each spectral band in the hyperspectral image cube. Thereby, it is possible to select the bands of higher repeatability for inclusion in the prediction model while bands of low repeatability are excluded. Further segregation of high and low repeatability bands takes place in the prediction model algorithm, which is based on a combination of a "Genetic Algorithm" and Partial Least Squares", (PLS-GA). In summary, modus operandi was developed, for deriving important plant growth attribute maps (yield, leaf nitrate, biomass and sugar percent in beets), from remote sensing imagery, with sufficient accuracy for precision cropping applications. This achievement is remarkable, given the inherently high cross-noice between the reference and remote imagery as well as the highly non-repeatable nature of remote sensing systems. The above methodologies may be readily adopted by commercial companies, which specialize in proving remotely sensed data to farmers.