Attacks by Termites (Blattoptera: Insecta) in cassava crops (Manioth esculenta Crantz.) in Daloa (Center-West, Côte d’Ivoire)

A study was carried out on the attack of termites in three cassava plots located in the zone of Daloa (town in the center-west of the Côte d’Ivoire). The main objective of this study was to ensure a sustainable productivity of cassava in the Daloa region by controlling termite’s pests of cassava crops according to the phenological stage, namely: the plot of cassava at the small stalk stage, the plot at the tuber production stage and the plot at the harvest stage. To this end, systematic excavations were carried out in the sections along the transects and plant-by-plant sampling in order to inventory the different species of termites on the plots and to highlight the damage they cause. This made it possible to identify 4 species of termites: Odontotermes sp., Macrotermes bellicosus, Pseudacanthotermes militaris and Nasutitermes latifrons, of which 1 species is common to all three environments. The comparative analysis of the different study environments showed that the plots at the production stage and at the harvest stage are the most colonized by termites. Odontotermes sp. observed only in plots at the small stage, as well as Nasutitermes latifrons which are only present on the plot at the production stage. Pseudacanthotermes militaris are best represented on all three plots.

Optimization of the precision gear grinding operation based on integrated information system

In accordance with the principles of hierarchical management, a comprehensive two-level management system is presented for the development and manufacturing of products for the stages of pre-production (the upper level of the management hierarchy) and for the actual production stage (the lower level of the management hierarchy). At the stage of pre-production, the gear grinding operation design on the “MAAG” type machines was carried out. For this purpose, a technique for optimizing the gear grinding parameters for a two dish-wheel rolling scheme has been developed, a mathematical optimization model containing an objective function with restrictions imposed on it has been created. The objective function is the gear grinding machine time, which depends on the operation parameters (gear grinding stock allowance, cutting modes, grinding wheel specification, part material) and the design features of the gears being ground (module, diameter, number of teeth, radius of curvature of the involutes). The article shows that at the stage of pre-production, the gear grinding optimization is a method of operation design. At the stage of actual production, a closed-loop automatic control system with feedback on the deviation of the adjustable value (gear grinding power) automatically supports the numerical power values that were found at the operation design stage, taking into account ensuring defect-free high-performance gear grinding (minimum number of working strokes and maximum longitudinal feeds). At this stage, i.e. when a robust longitudinal feed automatic control system is operating, the optimization carried out at the previous stage (pre-production) sets the functioning algorithm for the adaptive system with corresponding control algorithm. Thus, at the production stage (when the gear grinding machine is running), the operation optimization is a control method. Therefore, it is shown that with two-level control, the gear grinding operation optimization performs a dual function. On the one hand, it is a design method (at the pre-production stage), and on the other – a management method (at the actual production stage). With this approach, i.e. with the integration of production and its preparation based on a single two-level management, the efficiency of a single integrated design and production automation system is significantly higher due to general (unified) optimization, rather than partial one.

Sharpening a Cyclic Solvent Injection Technique in a Heavy Oil Reservoir from the Variation of the Nitrogen Injected as Dispersing: A Field Pilot, Colombia

This paper analyzes the use of a cyclic solvent injection technique (CSI) as a non-thermal EOR alternative to cyclic steam stimulation (CSS) for increasing the heavy oil recovery in a shallow reservoir located at the middle Magdalena basin in Colombia. A pilot well with less than 30% of water-cut and 10.9 °API was selected. Heavy natural gasoline of 30 °API obtained from the same reservoir was injected by using nitrogen (N2) as dispersing gas. Three procedures were performed being the procedure A, a Solvent slug injection of 60 bbl through the annular pushed and dispersed by 46,444 m3 (1,640 Mscf) of N2 immiscible (considering the low reservoir pressure). The procedure B consisted of injecting the same Solvent volume, but this time pushed by a third part of the N2 injected previously 15,481 m3 (547 Mscf). The procedure C consisted of only inject the same N2 volume than B procedure to analyze the heavy oil response without Solvent. There were collected production data, °API (by hydrometer), gas-flow and gas-gravity values using a liquid level software. Knowing the °API of each component in the laboratory—Solvent and heavy oil—the Solvent concentration from the real °API produced in production stages was calculated. All procedures had 48 hours of soaking, followed by a flowing process to tank to carefully release the excess of N2 before starting the production stage, avoiding gas lock issues. Without considering the Solvent injected, incremental oil production in procedure A was 232 bbl, in procedure B was 120 bbl and for procedure C, incremental oil only reached 11 bbl. With the last result it was determined the N2 injection by itself as a production mechanism without the Solvent effect in the in-situ heavy oil had a negligible effect on incremental oil. The gas-gravity showed the gas composition became heavier along the time, this considering the high-frequency N2 injections swept the methane near the well, requiring more time to produce the N2 traces from the porous media. The excess of N2 as a heavy Solvent dispersing mechanism does not warrant a better dilution effect since as observed in A and B procedures, Solvent concentration in the early production stage never dropped below 35% (17 °API), regardless of the N2 volume injected in the first two days. Finally, although A procedure had more incremental oil production (+93% than B), less N2 injected in B procedure was more efficient (+55% than A) regarding the incremental oil and N2 injected ratio (ONR).

Influence of Cardboard Pretreatment on the Determination of Starch Content by the Enzymatic Method

We determined the amount of starch by the enzymatic method in different samples of corrugated cardboard, including the sample produced of primary semi-finished products and corrugated cardboard made of 100 % waste paper. For starch enzymatic degradation, it is necessary to extract it from the corrugated board structure, since the processes of compression and keratinization of pulp fibers reduce the availability of starch for extraction. Enzymatic treatment requires the use of a complex amylolytic preparation for complete hydrolysis of starch to glucose. We were able to determine, respectively, 70 and 84 % of starch obtained from primary semi-finished products by mechanical methods, such as defibrillation in water and degradation in a liquid nitrogen medium, and added at the production stage of corrugated cardboard. It was shown that extraction with alkaline agents was necessary for more complete extraction of starch from corrugated cardboard. The influence of alkaline treatment on the characteristics of fibers of waste paper fractions obtained at the Sukhonsky Cardboard and Paper Mill has been analyzed. The fibers swell in alkali, resulting in an increase in fiber width and its shortening, as well as a decrease in crystallinity, which can be a positive opportunity for more complete starch extraction. Fiber swelling and crystallinity reduction are more intensive for the short fiber fraction compared to the long fiber fraction. When determining starch in corrugated cardboard using the standard method SCAN-P 91:09 SСAN-W 13:09 it was not possible to detect all the starch added at the production stage of corrugated cardboard from primary semi-finished products. Also the processing conditions of this methodology lead to degradation of the partially hydrolyzed starch. The most complete extraction of starch from corrugated cardboard was achieved by two stages of alkaline extraction under the following conditions: 5 % NaOH, temperature of 20 °C, the duration of each extraction – 2 h. Under these processing conditions it was possible to determine all the starch (22.8 kg/t) in the corrugated cardboard produced of primary semi-finished products with known consumption of starch; the starch content in the corrugated cardboard produced of 100 % waste paper was 48.2 kg/t. For citation: Khadyko I.A., Novozhilov E.V., Chukhchin D.G. Influence of Cardboard Pretreatment on the Determination of Starch Content by the Enzymatic Method. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 150–162. DOI: 10.37482/0536-1036-2021-5-150-162

Exploring the critical production risk factors for modular integrated construction projects

Purpose The factory production stage constitutes the bridge in the supply chains of modular integrated construction (MiC) projects. It embodies the fundamental differences between MiC and site-based construction. However, there is a poverty of knowledge of the uncertainties and risk events at the production stage. This study aims to investigate the critical production risk factors (PRFs) for MiC projects. Design/methodology/approach Comprehensive literature research and expert review identified and validated 22 candidate PRFs for MiC projects. A structured questionnaire survey was then used to gather opinions of domain experts in 18 countries on the relative impact of the validated PRFs for MiC projects. The collected data were analysed using multiple statistical techniques. Findings Statistical analysis identified nine critical PRFs for MiC projects. The top five include dimensional conflicts between modules during production; delays in production materials procurement; defective design; design information gap between designer and manufacturer; and limited capacity of manufacturers. Originality/value The study addressed the gap associated with identifying critical risk factors peculiar to the factory production stage of MiC projects. Its novelty lies in providing an opposite assessment of severities and prioritization of critical PRFs for MiC projects. The prioritized critical PRFs for MiC projects may inform resource allocation. Thus, it provides valuable information to MiC production specialists and project managers in their production risk planning and management strategies. The identified PRFs contribute to the theoretical checklist of MiC supply chain risk factors and may assist practitioners in assessing the severity levels of the PRFs of their MiC projects.

BREAD FRUITS PUDDING DENGAN PEMANIS ALAMI SEBAGAI ALTERNATIF DESSERT UNTUK PASIEN DIABETES MELLITUS

ABSTRACTThe aim of this study is modify dessert for patients or people with diabetes mellitus in the form of Bread Fruit Pudding with natural sweeteners. Bread Fruit Pudding products use the main ingredients of jelly and low fat milk and fruit as a sweet taste. Pudding product development into bread fruit pudding is attempted to increase public insight regarding the importance of considering the use of sugar and changing the negative stigma of society regarding the consumption of fruit with a sweet taste. The production stage of Bread Fruits Pudding products consists of the preparation of materials and tools, the processing stage using the boiling technique (100˚C) and serving (150 grams/serving). The nutritional content of Bread Fruits Pudding is 92.7 Calories of energy; 5.3 grams of protein; 3.8 grams of fat; 12.9 grams of carbohydrates; 2.2 grams of fiber and 6.6 grams of natural sugar. The result of the preference test obtained that 78% liked the appearance and portion of the product, 56% liked the taste and 89% liked the texture. The composition of ingredients in pudding products in the community generally uses a lot of sugar or added artificial sweeteners that increase the risk of Diabetes Mellitus, Pudding product development into bread fruit pudding is efforts are made to become a solution for pudding products that are safe for consumption without any risk to health in consuming it.

Equipment selection criteria for increasing the durability of printed circuit boards of on-board radio telemetry systems

Рассматривается критерий задачи корректного выбора типа оборудования для устранения причин возникновения соответствующих видов дефектов многослойных печатных плат бортовых радиотелеметрических систем на этапе производства. Ограничением является объем выделяемых на это средств. The criterion of the problem of the correct choice of the type of equipment to eliminate the causes of the corresponding types of defects of multilayer printed circuit boards of on-board radio telemetry systems at the production stage is considered. The limit is the amount of funds allocated for this purpose.

Study on Life-Cycle Energy Consumption and Greenhouse Gases Emission of Battery Electric Passenger Vehicles in China

Based on the localized data of environmental load, this study has established the life cycle assessment (LCA) model of battery electric passenger vehicle (BEPV) that be produced and used in China, and has evaluated the energy consumption and greenhouse gases (GHGs) emission during vehicle production and operation. The results show that the total energy consumption and GHG emissions are 438GJ and 37,100kg (in terms of CO2 equivalent) respectively. The share of GHG emissions in total emissions at the production stage is 24.6%, and 75.4% GHG emissions are contributed by the operational stage. The main source of energy consumption and GHG emissions at vehicle production stage is the extraction and processing of raw materials. The GHG emissions of raw materials production accounts for 75.0% in the GHG emissions of vehicle production and 18.0% in the GHG emissions of full life cycle. The scenario analysis shows that the application of recyclable materials, power grid GHG emission rates and vehicle energy consumption rates have significant influence on the carbon emissions in the life cycle of vehicle. Replacing primary metals with recycled metals can reduce GHG emissions of vehicle production by about 7.3%, and total GHG emissions can be reduced by about 1.8%. For every 1% decrease in GHG emissions per unit of electricity, the GHG emissions of operation stage will decrease by about 0.9%; for every 1.0% decrease in vehicle energy consumption rate, the total GHG emissions decrease by about 0.8%. Therefore, developing clean energy, reducing the proportion of coal power, optimizing the production of raw materials and increasing the application of recyclable materials are effective ways to improve the environmental performance of BEPV.