SEQUENTIAL DATA WEIGHTING PROCEDURES FOR COMBINED RATIO ESTIMATORS IN COMPLEX SAMPLE SURVEYS

In sample surveys weighting is applied to data to increase the quality of estimates. Data weighting can be used for several purposes. Sample design weights can be used to adjust the differences in selection probabilities for non-self weighting sample designs. Sample design weights, adjusted for nonresponse and non-coverage through the sequential data weighting process. The unequal selection probability designs represented the complex sampling designs. Among many reasons of weighting, the most important reasons are weighting for unequal probability of selection, compensation for nonresponse, and post-stratification. Many highly efficient estimation methods in survey sampling require strong information about auxiliary variables, x. The most common estimation methods using auxiliary information in estimation stage are regression and ratio estimator. This paper proposes a sequential data weighting procedure for the estimators of combined ratio mean in complex sample surveys and general variance estimation for the population ratio mean. To illustrate the utility of the proposed estimator, Turkish Demographic and Health Survey 2003 real life data is used. It is shown that the use of auxiliary information on weights can considerably improve the efficiency of the estimates

The efficiency of some post-emergence herbicides for controlling problematic weeds of lawn areas

This study was carried out to determine the effectiveness of some herbicides on weed species and weed population in the landscape area of Iğdır University Şehit Bülent Yurtseven Campus in 2021. In the study, herbicides with active ingredients, 2,4-D amine, Bromoxynil + MCPA, 2,4-D tri-isopropyl amine salt + Picloram, dicamba + triasulfuron, 2,4-D EHE + florasulam, Halosulfuron-methyl and Fluazifop-p-butyl as well as Bromoxynil + MCPA + dicamba + triasulfuron and 2,4-D amine + Fluazifop-p-butyl herbicide mixtures were used. The percentage effects of the herbicides applied in the study on weed dry weights, weed species, and the percentage effects of herbicides on these weed species were determined according to the 3 counts made at certain intervals for the weed species with a density of 1 weeds/m2 and above in the census.As a result of the study, a total of 14 weed species belonging to 8 families were determined in the trial area. Of these detected weed species, Trifolium  repens L. (5.49 weed/m2),  Cynodon dactylon (L.) Pers. (3.24 weed/m2),  Trifolium  pratense L.  (1.23 weed/m2), Melilotus albus Medik. (1.07 weed/m2) and Convolvulus arvensis L. (1.03 weed/m2), the density of 5 of them was determined as 1 weeds/m2 and above. As a result of the study, the lowest weed dry weights (2.12 g/m2) and the highest percentage effect (94.50%) were obtained in the 2,4-D tri-isopropyl amine salt + Picloram plots. The percentage effects of the herbicides applied in the study on the weed species varied according to the weed species and the herbicides used

Low damage etching of GaN surfaces via bias-assisted photoenhanced electrochemical oxidation in deionized water

Properties of GaN surfaces etched by bias-assisted photoenhanced electrochemical (PEC) oxidation in deionized water and subsequent removal of the oxidized material are investigated using Schottky diodes fabricated on etched surfaces. It is demonstrated that with a short anneal at 700°C after removal of the oxide, it is possible to obtain a low damage surface with near ideal breakdown and capacitance-voltage (C-V) characteristics. Good quality Schottky diodes are fabricated on surfaces etched as much as 120 nm. The undercutting of masked surfaces is also demonstrated. Thus, given the band-gap selectivity, the possibility to undercut masked areas, and the low damage surfaces that can be obtained, the process demonstrated in this paper is suitable for use in fabrication of self-aligned GaN bipolar transistor structures. © Springer-Verlag 2007

MCDM model for critical selection of building and insulation materials for optimising energy usage and environmental effect in production focus

In the context of sustainable buildings, an ecological study of building and insulating materials is critical since it may assist affirm or shift the path of new technology development. Utilising sustainable material is a part of the sustainable improvement. For this reason, material fabrication is the primary process for the energy usage and release of intense environmental gaseous. The fabrication of the insulation and building materials, as in every fabrication process, comprises an energy consumption of crude materials in addition to the pollutants’ release. In buildings, insulation is a relevant technological resolution for cutting energy usage. This study aims to assess the primary energy consumption and the environmental effects of the fabrication of building and thermal isolation materials by using a new hybrid MCDM model. The proposed new hybrid MCDM model includes Fuzzy FUCOM, CCSD and CRADIS methods. While the subjective weights of the criteria were determined with the fuzzy FUCOM method, the objective weights of the criteria were determined with the CCSD method. Construction materials were listed with the CRADIS method. According to the fuzzy FUCOM method, the most important criterion was determined as the CR3 criterion, while the most important criterion according to the CCSD method was determined as the CR1 criterion. According to the combined weights, the most important criterion was determined as the CR3 criterion. According to the CRADIS method, the material with the best performance was determined as Cement Plaster. The methodology used in this study is a novel approach therefore it has not been used in any study before. In addition, since the CRADIS method is a newly developed MCDM method, the number of articles related to this method is low. Therefore, this research gap will be filled with this study

Normative data and discriminative properties of short form 36 (SF-36) in Turkish urban population

BACKGROUND: SF-36 has been both translated into different languages and adapted to different cultures to obtain comparable data on health status internationally. However there have been only a limited number of studies focused on the discriminative ability of SF-36 regarding social and disease status in developing countries. The aim of this study was to obtain population norms of the short form 36 (SF-36) health survey and the association of SF-36 domains with demographic and socioeconomic variables in an urban population in Turkey. METHODS: A cross-sectional study. Face to face interviews were carried out with a sample of households. The sample was systematically selected from two urban Health Districts in Izmir, Turkey. The study group consisted of 1,279 people selected from a study population of 46,290 people aged 18 and over. RESULTS: Internal consistencies of the scales were high, with the exception of mental health and vitality. Physical health scales were associated with both age and gender. On the other hand, mental health scales were less strongly associated with age and gender. Women reported poorer health compared to men in general. Social risk factors (employment status, lower education and economic strain) were associated with worse health profiles. The SF-36 was found to be capable of discriminating disease status. CONCLUSION: Our findings, cautiously generalisable to urban population, suggest that the SF-36 can be a valuable tool for studies on health outcomes in Turkish population. SF-36 may also be a promising measure for research on health inequalities in Turkey and other developing countries

Enzyme-Nanoporous Gold Biocomposite: Excellent Biocatalyst with Improved Biocatalytic Performance and Stability

Background: Applications involving biomolecules, such as enzymes, antibodies, and other proteins as well as whole cells, are often hampered by their unstable nature at extremely high temperature and in organic solvents. Methodology/Principal Findings: We constructed enzyme-NPG biocomposites by assembling various enzymes onto the surface of nanoporous gold (NPG), which showed much enhanced biocatalytic performance and stability. Various enzymes with different molecular sizes were successfully tethered onto NPG, and the loadings were 3.6, 3.1 and 0.8 mg g 21 for lipase, catalase and horseradish peroxidase, respectively. The enzyme-NPG biocomposites exhibited remarkable catalytic activities which were fully comparable to those of free enzymes. They also presented enhanced stability, with 74, 78 and 53 % of enzymatic activity retained after 20 successive batch reactions. Moreover, these novel biocomposites possessed significantly enhanced reaction durability under various thermal and in organic solvent systems. In a sample transesterification reaction, a high conversion rate was readily achieved by using the lipase-NPG biocomposite. Conclusion/Significance: These nano-biocomposite materials hold great potential in applications such as biosensing, molecular electronics, catalysis, and controlled delivery