A Hybrid and Self-Adaptive Differential Evolution Algorithm for the Multi-Depot Vehicle Routing Problem in Egg Distribution

This paper presents the Hybrid and Self-Adaptive Differential Evolution algorithms (HSADE) to solve an egg distribution problem in Thailand. We introduce and formalize a model for a multi-product, multi-depot vehicle routing problem with a time window, a heterogeneous fleet and inventory restrictions. The goal of the problem is to minimize the total cost. The multiple products comprise customers’ demands with different egg sizes. This paper presents a Mixed Integer Linear Programming (MILP) model, an initial solution-based constructive heuristic, a new self-adaptive mutation strategy, and a neighborhood search structure with the probability to improve DE. The two measurements of criteria are the heuristic performance (HP) compared with the solution obtained by MILP and the relative improvement (RI) of the solution compared with Thailand’s current egg distribution practice. The computational results show that the performance of HSADE is better than the current practice, and HSADE can provide on average a 14.13% improvement in total cost. Additionally, our proposed algorithm can be applied to similar agriculture logistics in Thailand and worldwide.

Reproductive traits and spawning activity of striped eel catfish (Plotosidae) in Kolono Bay, Indonesia

Asriyana A, Halili H. 2021. Reproductive traits and spawning activity of striped eel catfish (Plotosidae) in Kolono Bay, Indonesia. Biodiversitas 22: 3020-3028. Reproduction is a natural process for a species to ensure its sustainability in nature. This study aimed to investigate the reproductive traits and spawning activity of the striped eel catfish in Kolono Bay, South Konawe District, Southeast Sulawesi, Indonesia. A total of 965 individuals were collected monthly from June 2020 to May 2021 by using bottom experimental gillnets. Spent/spawning stages of the male and female fish were found during the East season (June-August). The proportions of the spent/spawning stages of male and female fish were 60% and 55.56% and the values of the gonadal somatic index were 1.19 ± 0.53 and 2.19 ± 3.47, respectively during the East season, indicate occurring the peak spawning in this season. Females matured gonads more rapidly at 198.3 mm compared to males at 224.5 mm. Female fecundity was 1,730 ± 390 eggs, with an egg diameter of about 0.11-1.35 mm. Striped eel catfish is a total spawner fish that has one mode of egg distribution pattern. During the East season, it needs protection for spawning. The findings will help in designing effective management and developmental strategies to conserve the striped eel catfish population in the future.

Generating New Flexible Lifetime Class of Distributions Based on Competing Risks and Frailty Models

New classes of continuous distributions have been generated, in the last decad, based on a compounding procedure arises on a latent competing risks problem. This procedure assumes the homogeneity between the population individuals. In this paper, a new lifetime distribution is generated, assuming the heterogeneity at both population and individual levels, called Extended Gamma Gompertz (EGG) distribution. This distribution shows very desirable exibility of its hazard function. Some properties of the proposed distribution are given. Maximum likelihood estimation technique is used to estimate the parameters. A simulation study is performed to examine the performance of the proposed model. Finally, application to a real data set is given to exemplify the utility of the EGG distribution.

Penerapan Metode Weight Product (WP) Untuk Menentukan Pengalokasian Pendistribusian Telur Terbaik Di Kecamatan Pantai Labu

Distribution is an important thing in business activities, especially for distribution companies or distributors. Delays in distribution will reduce customer service levels. The method used is WP (Weighted Product), because Weighted product is one of the right choice of method to solve complex problems and Weighted Product can produce structured calculations on problems that have sub-sub-criteria for the decision to be built. from this research is to determine the best egg distribution location in the pumpkin beach district using the Weighted Product (WP) method. The Weighted Product (WP) method is a multi-criteria analysis decision and is a multi-criteria decision-making method. WP is a set of alternative decisions described in terms of several criteria. In the WP method there is no need for matrix manipulation because this method multiplies the assessment results of each attribute. The results of the research are based on the results of the ranking using the Weighted Product (WP) method to determine the best distribution location in the pumpkin beach district, so the greatest value is Grosir 2 with a value of 0.2309 which can be chosen to be the best distribution location. weights so that they can be used with that method.

Use of ovitraps for the seasonal and spatial monitoring of Aedes spp. in an area endemic for arboviruses in Northeast Brazil

Introduction: Due to recent outbreaks of Dengue and Chikungunya and an absence of effective monitoring of the mosquito Aedes spp. in the municipality of São Raimundo das Mangabeiras, State of Maranhão, we aimed to demonstrate the potential of ovitraps used together with mathematical models and geotechnology to improve control of this mosquito. Methodology: From January to December of 2017, ovitraps were set up in five different neighborhoods (Centro, Vila Cardoso, Nazaré, São José e São Francisco). Positivity indices were calculated for each ovitraps, besides the egg density and average number of eggs. Some of the eggs were used for species identification. Mathematical models of correlation and logistic regression were used to evaluate the influence of abiotic factors on egg distribution during each month. Spatial analysis was carried out using georeferencing. Results: A total of 4,453 eggs were counted, with A. aegypti and A. albopictus present in each month and neighborhood. The mathematical models show that rainfall can result in a significant increase in the number of eggs. Entomological calculation indicates that there is a high risk of dissemination of arboviruses in the area. Spatially, it was possible to indicate sites with the largest number of collected eggs, which may facilitate future interventions. Conclusions: As such, ovitraps have proven to be an effective and low cost method for the monitoring of Aedes spp., and that its use may help in arboviruses prevention campaigns.

Nonpreference for Oviposition of Sugarcane Borer (Lepidoptera: Crambidae) in Sugarcane Seedlings Is Influenced by Ripening Group and Plant Age

The sugarcane borer Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) is considered the main sugarcane pest in many countries. The use of plant genotypes less preferred by insects are among the alternative methods to control this species which can be used alone or associated with other control methods such as biological control in Integrated Pest Management (IPM) programs. We assessed if the nonpreference for oviposition of D. saccharalis in sugarcane genotypes established by seedlings is different according to ripening group and plant age. For that purpose, four experiments were performed: 1) seedlings of early-ripening genotypes, 2) seedlings of late-ripening genotypes, 3) and mix of early- and late-ripening genotypes, seedlings, and 4) plants. There were least preferred genotypes for oviposition by D. saccharalis among seedlings of early-ripening (RB965902 and RB966928) and late-ripening (RB987935) genotypes. It was also observed when the groups were mixed as seedlings (RB965902) or plants (RB925345). The nonpreference for egg deposition in different ripening groups and plant age might be useful to integrate with other strategies for the management of D. saccharalis. Moreover, results of egg distribution might indicate the likely position of resistance factors on leaves, whether morphological or chemical.