Effect of Proportion of Missing Data on Application of Data Imputation in Pavement Management Systems

Missing data are commonly found in pavement condition/performance databases. A common practice today is to apply statistical imputation methods to replace the missing data with imputed values. It is thus important for pavement management decision makers to know the uncertainty and errors involved in the use of datasets with imputed values in their analysis. An equally important information of practical significance is the maximum allowable proportion of missing data (i.e. level of data missingness in the pavement condition/performance records) that will still produce results with acceptable magnitude of error or risk when using imputed data. This paper proposes a procedure for determining such useful information. A numerical example analyzing pavement roughness data is presented to demonstrate the procedure through evaluating the error and reliability characteristics of imputed data. The roughness data of three road sections were obtained from the LTPP database. From these data records, datasets with different proportions of missing data were randomly generated to study the effect of level of data missingness. The analysis shows that the errors of imputed data increased with the level of data missingness, and their magnitudes are significantly affected by the effect of pavement rehabilitation. On the application of data imputation in PMS, the study suggests that at 95% confidence level, 25% of missing data appears to be a reasonable allowable maximum limit for analyzing pavement roughness time series data not involving rehabilitation within the analysis period. When pavement rehabilitation occurs within the analysis period, the maximum proportion of imputed data should be limited to 15%

Hydrodynamic analysis on semi-submersible playform

As the population increases exponentially and demand for inexpensive energy sources continue to raise, exploration and production for fossil fuel is rapidly growing. In order to meet the demands, the exploration has taken one step further to the extreme deep sea. Floating production platform design is a far more efficient and economical rather that fixed production platform at this depth

The Juridical Review of the Consequences of Online & Offline Promotion of Notary Position Conducted by A Notary based on The Notary's Ethics Code

. This study aims to determine the consequences borne by notaries on notaries who promote positions online and offline based on the notary's code of ethics. The research method used is a normative juridical approach, (library research), which is a research approach that uses the main law, as well as reviewing several theoretical matters related to legal principles, legal doctrines, regulations and legal systems related to research What is being discussed using secondary data includes principles, rules, norms, and legal rules contained in laws and regulations and other regulations. The result of this study is that violations of the code of ethics committed by notaries will provide consequences regulated in the notary code of ethics in the form of reprimands, warnings, temporary dismissals, respectful dismissals, and disrespectful dismissals decided by the Notary Honor Council established by the Indonesian Notary Association (INI)

Hydrodynamic analysis on semi-submersible playform

As the population increases exponentially and demand for inexpensive energy sources continue to raise, exploration and production for fossil fuel is rapidly growing. In order to meet the demands, the exploration has taken one step further to the extreme deep sea. Floating production platform design is a far more efficient and economical rather that fixed production platform at this depth

The strength of nuclear shell effects at N=126 in the r-process region

We have investigated nuclear shell effects across the magic number N=126 in the region of the r-process path. Microscopic calculations have been performed using the relativistic Hartree-Bogoliubov approach within the framework of the RMF theory for isotopic chains of rare-earth nuclei in the r-process region. The Lagrangian model NL-SV1 with the inclusion of the vector self-coupling of omega meson has been employed. The RMF results show that the shell effects at N=126 remain strong and exhibit only a slight reduction in the strength in going from the r-process path to the neutron drip line. This is in striking contrast to a systematic weakening of the shell effects at N=82 in the r-process region predicted earlier in the similar approach. In comparison the shell effects with microscopic-macroscopic mass formulae show a near constancy of shell gaps leading to strong shell effects in the region of r-process path to the drip line. A recent analysis of solar-system r-process abundances in a prompt supernova explosion model using various mass formulae including the recently introduced mass tables based upon HFB approach shows that whilst mass formulae with weak shell effects at N=126 give rise to a spread and an overproduction of nuclides near the third abundance peak at A~190, mass tables with droplet models showing stronger shell effects are able to reproduce the abundance features near the third peak appropriately. In comparison, several analyses of the second r-process peak at A~130 have required weakened shell effects at N=82. Our predictions in the RMF theory with NL-SV1, which exhibit weaker shell effects at N=82 and stronger one at N=126 in the r-process region, support the conjecture that a different nature of the shell effects at the magic numbers may be at play in r-process nucleosynthesis of heavy nuclei.Comment: 14 pages, 8 figures; submitted to Physical Review C. Part of this work was presented at Nuclear Physics in Astrophysics II, 20th International Nuclear Physics Divisional Conference of the European Physical Society, at Debrecen, Hungary, May 16-20, 200

The COVID-19 pandemic and stock market performance of transportation and travel services firms: a cross-country study

This paper examined the firm-specific abnormal returns of transportation and travel services sectors from the USA, UK, France, China, India, Mexico, Turkey, and Thailand in response to Coronavirus Disease 2019 (COVID-19) using event study methodology. Our results revealed that investors in developed countries provide significant long term abnormal returns for the first 101 days. Furthermore, no significant cumulative average abnormal returns (CAAR) were found in response to the COVID-19 outbreak, travel restrictions, lockdown, stimulus package, and historical decline in oil prices except in the case of the USA. It is concluded that with the gradual increase in new cases and deaths, abnormal returns are also adjusted, making the effects of these events insignificant at the time of their occurrence. Results also showed that firms in developing countries recognized significant negative abnormal returns in response to the second wave of COVID-19. These results are useful for investors in devising investment strategies relevant to contextual settings

Towards green computing for Internet of Things: energy oriented path and message scheduling approach

Recently, energy efficiency in sensor enabled wire-less network domain has witnessed significant attention from both academia and industries. It is an enabling technological advancement towards green computing in Internet of Things (IoT) eventually supporting sensor generated big data processing for smart cities. Related literature on energy efficiency in sensor enabled wireless network environments focuses on one aspects either energy oriented path selection or energy oriented message scheduling. The definition of path also varies in literature without considering links towards energy efficiency. In this context, this paper proposes an energy oriented path selection and message scheduling framework for sensor enabled wireless network environments. The technical novelty focuses on effective cooperation between path selection and message scheduling considering links on path, location of message sender, and number of processor in sensor towards energy efficiency. Specifically, a path selection strategy is developed based on shortest path and less number of links on path (SPLL). The location of message sender, and number of processor in specific sensor are utilized for developing a longer hops (LH) message scheduling approach. A system model is presented based on M/M/1 queuing analysis to showcase the effective cooperation of SPLL and LH towards energy efficiency. Simulation oriented comparative performance evaluation attest the energy efficiency of the proposed framework as compared to the state-of-the-art techniques considering number of energy oriented metrics

Imaging magnetic vortex configurations in ferromagnetic nanotubes

We image the remnant magnetization configurations of CoFeB and permalloy nanotubes (NTs) using x-ray magnetic circular dichroism photo-emission electron microscopy. The images provide direct evidence for flux-closure configurations, including a global vortex state, in which magnetization points circumferentially around the NT axis. Furthermore, micromagnetic simulations predict and measurements confirm that vortex states can be programmed as the equilibrium remnant magnetization configurations by reducing the NT aspect ratio.Comment: 14 pages, 4 figures, link to supplementary informatio