Design and Assembly of an Improvised Logic Gates Simulator

This study aimed at designing and assembling an improvised Logic Gates Simulator that can be utilized as an instructional device in basic digital electronics instruction at Caraga State University Cabadbaran Campus, Philippines. This instructional device is believed to enhance the teaching-learning process and would also help address the scarcity of instructional equipment in the school and in the country. Descriptive method of research was employed to come up with the design of the simulator based on the course content of basic digital electronics subject. Acceptability of the improvised simulator based on standards set in this study was?gathered from the experts as respondents using a self-made questionnaire. The data were treated using average weighted mean utilizing parametric scales with verbal descriptions. Findings revealed that the improvised logic gates simulator is highly acceptable in terms of its cost and availability of components,?design and construction,operations, and troubleshooting features. It is concluded that the improvised logic gates simulator is at par in terms of standards on instructional devices based on the evaluation results of experts and is therefore recommended to be used in basic digital electronics instruction. The simulator is an innovative answer and an alternate solution to the scarcity of instructional materials and devices at Caraga State University Cabadbaran Campus.

Assessing the Biomass Potential of Major Industrial Tree Plantation Species for Green Energy Production

Energy requirements in both urban and rural areas are increasing giving added stress to the power generators and energy sources, thus blackouts are becoming common scenarios. Renewable energy from tree biomass is being eyed to provide solution to insufficient energy supply. A component of the green energy generation project is to assess the biomass potential of major industrial tree plantation species in the region at various ages, to determine the sustainability of a biomass-based green energy generation. Actual field measurements of biomass in selected plantations were conducted. In the field inventory, a plot measuring 10 × 50 meters was laid out randomly on the sampling site. For all trees inside the plot, the basal diameter and diameter at breast height for ages 1 to 2 years old and 3 to 5 years old, respectively were recorded. The results revealed that the biomass of major industrial tree species in Year 1 followed the order: Mangium (Acacia mangium) > Ipil-ipil (Leucaena leucocephala) > Falcata (Paraserianthes falcataria) > Bagras (Eucalyptus deglupta). However, as the trees mature, the biomass generation changed with Falcata overtaking Mangium. The order then was: Falcata (Paraserianthes falcataria) > Mangium (Acacia mangium) > Ipil-ipil (Leucaena leucocephala) > Bagras (Eucalyptus deglupta). Of the major industrial tree species, Falcata (Paraserianthes falcataria) and Mangium (Acacia mangium) are noted to have the biggest potential in supplying the biomass requirement of the green energy plant.

Interdependence between Natural Habitats and Ricefields for Rice Pest Management in the Agusan Marsh Floodplain

This paper describes how aquatic insect diversity in major natural habitats of Agusan marsh relates with nearby ricefields to determine the interdependence between them for sustainable rice production through natural pest control and for conservation of aquatic fauna in the marsh. Sampling for one year including two cropping seasons of rice production was conducted in various natural habitats of the marsh and in the adjoining rice fields. Both the natural habitats and rice fields were characterized in relation to determining habitat suitability for aquatic insects. The sedge-dominated swamp had the highest diversity among the natural habitats, while the fern-dominated swamp had the lowest. In the adjacent ricefields, diversity was similarly highest in the site near the sedge-dominated swamp, while the lowest was in the ricefields adjoining the Sago forest. Species composition of aquatic insects among the habitats differed between the wet and dry seasons. However, similarity patterns exist between natural habitats and rice fields. The closer similarity in species composition between natural habitats and ricefields indicates habitat connectivity which is an important consideration in planning and effective pest management and ecologically sound rice farming in the marsh.

红角鸮的食性及育雏行为初报

红角鸮（Otus sunia）广泛分布于东亚和南亚。2012和2013年的两个繁殖季节,在江苏省南京大学浦口校区通过红外摄像观察记录了红角鸮的摄食及育雏行为,统计了亲代红角鸮育雏食物的种类、育雏的时间和次数。以1 h为一个时段,利用单因素方差分析（ANOVA）及Student-Newman-Keulsa多重比较法分析各时段之间育雏频次的差异。亲鸟育雏的食物大部分为直翅目（62%）和鳞翅目（18%）昆虫,以及非昆虫类的无脊椎动物,如蜘蛛（8%）和唇足动物（7%）,红角鸮也捕食小型陆栖脊椎动物例如田鼠、壁虎等育雏,但比例甚低（3%）。红角鸮育雏节律较为明显,亲鸟主要集中在夜间外出觅食,但在白天也有觅食行为。夜间共有三个育雏高峰,分别为日落之后的19：00-20：00时和21：00-22：00时以及日出之前的04：00-05：00时。

Impact of vaccine supplies and delays on optimal control of the COVID-19 pandemic:mapping interventions for the Philippines

Background::Around the world,controlling the COVID-19 pandemic requires national coordination of multiple intervention strategies.As vaccinations are globally introduced into the repertoire of available interventions,it is important to consider how changes in the local supply of vaccines,including delays in administration,may be addressed through existing policy levers.This study aims to identify the optimal level of interventions for COVID-19 from 2021 to 2022 in the Philippines,which as a developing country is particularly vulnerable to shifting assumptions around vaccine availability.Furthermore,we explore optimal strategies in scenarios featuring delays in vaccine administration,expansions of vaccine supply,and limited combinations of interventions.Methods::Embedding our work within the local policy landscape,we apply optimal control theory to the compartmental model of COVID-19 used by the Philippine government’s pandemic surveillance platform and introduce four controls:(a)precautionary measures like community quarantines,(b)detection of asymptomatic cases,(c)detection of symptomatic cases,and(d)vaccinations.The model is fitted to local data using an L-BFGS minimization procedure.Optimality conditions are identified using Pontryagin’s minimum principle and numerically solved using the forward-backward sweep method.Results::Simulation results indicate that early and effective implementation of both precautionary measures and symptomatic case detection is vital for averting the most infections at an efficient cost,resulting in>99%reduction of infections compared to the no-control scenario.Expanding vaccine administration capacity to 440,000 full immunizations daily will reduce the overall cost of optimal strategy by 25%,while allowing for a faster relaxation of more resource-intensive interventions.Furthermore,delays in vaccine administration require compensatory increases in the remaining policy levers to maintain a minimal number of infections.For example,delaying the vaccines by 180 days(6 months)will result in an 18%increase in the cost of the optimal strategy.Conclusion::We conclude with practical insights regarding policy priorities particularly attuned to the Philippine context,but also applicable more broadly in similar resource-constrained settings.We emphasize three key takeaways of(a)sustaining efficient case detection,isolation,and treatment strategies;(b)expanding not only vaccine supply but also the capacity to administer them,and;(c)timeliness and consistency in adopting policy measures.