Divide and Conquer: A Quick Scheme for Symbolic Regression

Symbolic regression (SR), as a special machine learning method, can produce mathematical models with explicit expressions. It has received increasing attention in recent years. However, finding a concise, accurate expression is still challenging because of its huge search space. In this work, a divide and conquer (D&C) scheme is proposed. It tries to divide the search space into a number of orthogonal sub-spaces based on the separability feature inferred from the sample data (dividing process). For each sub-space, a sub-function is learned (conquering process). The target model function is then reconstructed with the sub-functions according to their separability patterns. To this end, a separability pattern detecting technique, bi-correlation test (Bi-CT), is also proposed. Note that the sub-functions could be determined by any of the existing SR methods, which makes D&C easy to use. The D&C powered SR has been tested on many symbolic regression problems, and the study shows that D&C can help SR to get the target function more quickly and reliably.

A Numerical Study on Heat Transfer in the Channel with Delta Winglet Pair Vortex Generators

In this study, the effect of the vortex generators on the heat transfer and flow characteristics in a rectangular channel is investigated numerically by finite volume method. The governing equations are discretized using QUICK scheme. The numerical results are validated against published experimental data. In this paper, the effects of the winglet aspect ratio and the distance between the vertices of the winglets on the heat transfer and hydrodynamic characteristics of the flow are surveyed. In addition, to achieve the optimum amount of heat transfer, it is important to know the proper arrangement of the triangular winglet pairs as well as their suitable position. Therefore, the appropriate values of the longitudinal and transverse pitch are presented in this paper. The results show that the winglet with the aspect ratio of 1.75 has the best thermal and hydrodynamic performance. Furthermore, the transverse pitch of 1.24 causes 6.5% growth in the average Nusselt number.

DEVELOPMENT OF QUICK SCHEME IDENTIFICATION OF LISTERIA USING PHAGE BIOPREPARATION L.M 4 УЛГАУ

The causative agent Listeria monocytogenes causes listeriosis, a severe foodborne illness associated with high mortality. Rapid and sensitive methods are required to detect and identify this pathogen in the food production process. The article presents the results of research on the development of technological parameters for the production of biopreparation based on the bacteriophage L. m 4 UlSAU for quick identification of bacteria of the genus Listeria with its help. It was established that for the production of L. m 4 phage of UlSAU with maximum titers, the optimal parameters are: multiplicity of MOI 1 infection, cultivation temperature-28°C, incubation time of the phage/ culture system – 6 hours. Based on these results, we have offered technological scheme for the production of phage biopreparation L. m 4 UlSAU, which includes the following steps: confirmation of biological properties of indicator phage and increasing its titer (if necessary), verification and confirmation of biological properties of indicator culture, production of phage biopreparation and control of its indicators. Accelerated scheme for Listeria identification was offered with the help of prepared biological product based on L. m 4 bacteriophage of UlSAU. The scheme was tested on samples of chicken meat and minced meat semi finished products artificially contaminated with Listeria monocytogenes bacteria in concentrations 101-105 CFU/ml. It was established that the proposed scheme of listeria identification allows to reduce the duration of studies by 84 hours in comparison with the traditional bacteriological method and to detect listeria at a concentration of 100 CFU/ml (g) in 82 hours. The phagoidentification time at the pure culture typing stage is 18 hours.

Get-Rich Quick scheme: Malaysian current legal development

Purpose In Malaysia, Get-Rich-Quick scheme (GRQS) is one of the financial fraud activities prohibited under Malaysian law. The common facet of such schemes involves plans that promise unrealistic rates of returns, and this new scheme continues to proliferate every year as the list of illegal investment companies and websites are growing. Indeed, GRQS will remain proliferating as long as there are people who are easily lured by the promise that wealth can be generated with little skill, effort or time. This paper aims to explain the phenomenon of GRQS in light of the existing laws in Malaysia. This paper also highlights the current development of Australian law pertaining to GRQS for comparative purpose. Design/methodology/approach This paper mainly relies on statutes as its primary sources of information. As such, this paper analyses the scope and provisions of the relevant laws that regulate GRQS and compare the existing GRQS provisions that are equivalent with Australian law. Findings Malaysia has comprehensive laws to combat GRQS activities. However, these laws are far from perfection, and only with immediate amendments, GRQS problems can be resolved more effectively. One of the weaknesses of current Malaysian laws to tackle GRQS is the lack of more stringent punishment against the operators of GRQS as well as the participants of the scheme. A comparison with equivalent GRQS law in Australia demonstrates that Australian laws provide a wide range of punishment to the operators and prohibits participation in GRQS. More importantly, Australia regards the offense as a strict liability offense where the mens rea or guilty mind of the perpetrators is exempted. Indeed, numerous proceedings have been instituted in the Australian Court against the operators and participants of GRQS. Originality/value This paper analyses the scope of relevant laws in Malaysia to combat GRQS and examines the strengths and weaknesses of these laws. This paper also compares Malaysian law with equivalent GRQS-related laws available in Australia. This paper further suggests that Malaysia should regulate sterner punishment for operators and participants of the scheme and that the offense is categorized under a strict liability offense where the mens rea or guilty mind of the offender is exempted.

Subjective inflation: phenomenology’s get-rich-quick scheme

How do we explain the seemingly rich nature of visual phenomenology while accounting for impoverished perception in the periphery? This apparent mismatch has led some to posit that rich phenomenological content overflows cognitive access, whereas others hold that phenomenology is in fact sparse and constrained by cognitive access. Here, we review this Rich vs Sparse debate as it relates to a phenomenon called subjective inflation, wherein minimally attended or peripheral visual perception tends to be subjectively evaluated as more reliable than attended or foveal perception when objective performance is matched. We argue that subjective inflation can account for rich phenomenology without invoking phenomenological overflow. On this view, visual phenomenology is constrained by cognitive access, but seemingly inflated above what would be predicted based on sparse sensory content.

Nonlinear Characteristics of a Sudden Expansion Followed by Sudden Contraction Channel

The flow and heat transfer in a sudden expansion followed by sudden contraction channel are widely applied in industry, and it is also a classic problem for theoretical study. In this article, the SIMPLE algorithm with QUICK scheme were used to study the flow and heat transfer in a sudden expansion followed by sudden contraction channel. The nonlinear characteristics and temperature field were investigated for various Reynolds number and geometrical dimension. The results show that the temperature field evolves from symmetric to asymmetric state with the increasing Re. When Re ≥ Rec, the flow loses stability and from symmetric to asymmetric via a symmetry-breaking bifurcation; when the Reynolds number continues to increase, the fluid flow and heat transfer oscillation. The nonlinear characteristics of flow and heat transfer within the channel is further analyzed.