Influence of Sulphuric Acid on the Compressive Strength of Ternary Blended Geopolymer Mortar

The deteriorating effect of acid media on cement based constructions has become a worrying problem all over the world. These media generally occur as solutions in various branches of the industry, acid rains and mists, and acid ground-waters. A very popular form of acid attack on concrete that is usually referred to as biogenic sulphuric acid attack also occurs in both industrial and urban sewer systems. The emergence of new cementitious materials, like geopolymer cements, during the past decades necessitates detailed experimental work and research activities to investigate their durability in aggressive acid environments. The study therefore explored the development of alkali-activated CPA-SHA-MK ternary blended geopolymer mortar (GPM) using sodium silicate (Na2Si3) and sodium hydroxide (NAOH) solutions with 9M constant concentration as alkaline activators under both the aggressive and ambient-temperature curing media. The mass ratio of sodium silicate to sodium hydroxide (NS: NH) and as well as the binder to fine aggregate were fixed at 2.5 and 0.8 respectively. The durability of the ternary blended geopolymer mortar was examined through acid resistance test using 50 mm cubes after 28, 56 and 90 days of curing. The results revealed that the setting time prolonged as the replacement levels of RHA-MK increased at a decrease in the replacement levels of CPA. The results also showed that both the PCM and GPM samples studied suffered mass and strength losses in the acid solution and the loss increases at an increase in the hydration periods. The strength losses were observed to be higher in PCM mix (12.19 N/mm2 at 90 days) as compared to the GPMs (6.67 N/mm2 at 90 days) while the mix incorporated 50% CPA, 33% MK and 17% RHA (C50M33R17) was observed to be better compared to other mixes in durability behaviour. The study therefore recommends C50M33R17 mix proportion for good durability performance.&nbsp

Adaptive Load Frequency Control of Nigerian Hydrothermal System Using Unsupervised and Supervised Learning Neural Networks

This work presents a novel load frequency control design approach for a two-area power system that relies on unsupervised and supervised learning neural network structure. Central to this approach is the prediction of the load disturbance of each area at every minute interval that is uniquely assigned to a cluster via unsupervised learning process. The controller feedback gains corresponding to each cluster center are determined using modal control technique. Thereafter, supervised learning neural network (SLNN) is employed to learn the mapping between each cluster center and its feedback gains. A real time load disturbance in either or both areas activates the appropriate SLNN to generate the corresponding feedback gains. The effectiveness of the control framework is evaluated on the Nigerian hydrothermal system. Several far-reaching simulation results obtained from the test system are presented and discussed to highlight the advantages of the proposed approach

Validation of the Bahasa Malaysia version of the Coping Inventory for Stressful Situation (CISS)

Introduction: There is an appealing need to have a validated Bahasa Malaysia (BM) questionnaire that is able to gauge stress coping styles among Malaysian population. A culturally accepted questionnaire will generate further research in the aspect of stress coping patterns in the Malaysia population. Objective: To translate the Coping Inventory for Stressful Situations (CISS) questionnaire into BM and to determine the construct validity, reliability and other psychometric properties of the translated BM version of the English CISS 48-item. Method: Two parallel forward and backward translations were done in BM in accordance to guideline and its validation was determined by using confirmatory factor analysis among 200 Malaysian subjects. Results: The BM CISS had very good Cronbach’s alpha values, 0.91, 0.89 and 0.85 respectively for Task-, Emotional- and Avoidance-oriented. The overall Cronbach’s alpha was 0.91. It also had good factor loading for most of its items where 44 items out of 48 had Confirmatory Factor Analysis values of more than 4.0. Conclusions: BM CISS had been adequately and correctly translated into Bahasa Malaysia with high psychometric properties. Minimal readjustment may be required in a few of its items to obtain excellent results

Prevalensi Faktor Risiko Orang Dewasa yang Memiliki Gejala Subjektif Penyakit Jantung Koroner di Gunung Kidul

The prevalence of risk factors in adults who have subjective coronary heart disease symptoms in Gunung KidulPurposeThis study aimed to identify the risk factors of smoking, passive smoking, physical activity, and consumption of fruits and vegetables in adults who have subjective coronary heart disease symptoms.MethodsThis study used secondary data involving 586 participants. Data were obtained from the survey of clean and healthy behaviors conducted by the provincial health office in 2015. Samples were adults aged 18-60 and aged < 18 who have been married and settled in Gunungkidul. Analysis of the relationship between variables used chi-square and Poisson regression tests.ResultsThe prevalence of smoking was lower in those who experience coronary heart disease subjective symptoms than those who do not have this symptom. Multivariate analysis showed a significant association between passive smoking, fruit and vegetable consumption, level of education and coronary heart disease subjective symptoms.ConclusionThis study recommends making a regulation of non-smoking areas and its application in the society. It is also necessary to do socialization and counseling about the dangers, symptoms, and prevention of coronary heart disease

Effects of Soil Properties and Operational Variables on the Compactibility of a Sandy Loam Soil

The evaluation of an empirical equation for the determination of degree of compaction of a sandy loam soil was carried out using seven soil physical properties and four compaction operational variables. The soil used was obtained from a borrow pit in Gombe. Five levels of compactive effort, E/A, using a drop-weight type compactor varying from 107.91 to 539.55 Nm was used to compact each of seven pairs of embankment and slice thicknesses (Z, z respectively) with Z varying from 210 to 450 mm and z from 30 to 210 mm. The developed empirical equation, π1&nbsp;= Gπ2k&nbsp;in which π1 is the dimensionless degree of compaction and π2&nbsp;is a dimensionless combination of the soil properties and the compaction operational variables, has a very high coefficient of determination, r2&nbsp;varying from 98.8% to 98.9%. G and k are each polynomial functions of compactive effort per loading, eL. that is, G = αGeL2+βG&nbsp;eL&nbsp;+ λG&nbsp;and k=αkeL2+βkeL+ λk. The values of the respective α, β and λ are highly statistically significant at 99.95 confidence level. The “dependent” variables (G and k) are highly correlated at 99.95% confidence level of statistical significance with the “independent” variable (eL). The multivariate expression of the degree of compaction obtained in this study shows that compaction depends, not only on cumulative compactive effort, E/A, but also on the compactive effort per loading (eL), embankment and slice thicknesses (Z and z respectively) as well as on easy-to-measure soil properties (i.e. soil texture, soil uniformity coefficient, antecedent soil moisture and antecedent bulk density)

User friendly system for the visually impaired in learning Al-Quran

This study presents a method to enable the visually impaired Muslim to learn and read the Al-Quran using Braille Display with software help. The system reads the database which contains all verses of Al-Quran and user will need to select the verse and ayah to read. Besides that, this system can be used in a class to teach visually impaired students to learn Al-Quran. Every word or character typed by the instructor in the main Braille Panel will be transmitted to the sub Braille Panel that is connected to the main Braille Panel. The selected verse of Al-Quran and ayah will also generate an index before being transmitted to the Braille Panel. The index will be transmitted to the Braille Display for people to touch and read the display. A user friendly Graphical User Interface (GUI) will be used to fulfill the ergonomics for the visually impaired user's physical capabilities. Several approaches are used to design and implement the interface for the visually impaired like speech or sound output and Braille display. The Braille codes can be displayed using the Braille panel. The design interface and structure of the system for the visually impaired users in learning Al-Quran is presented

Hubungan Perilaku Komunikasi dan Pengembangan Kapasitas Pelaku Agribisnis Perikanan Air Tawar di Padang, Sumatera Barat

Penelitian ini bertujuan: (1) Menganalisis tingkat konvergensi komunikasi dalam pengembangan kapasitas pelaku agribisnis perikanan air tawar. (2) Menganalisis hubungan perilaku komunikasi dalam mengakses informasi dengan konvergensi komunikasi pengembangan kapasitas pelaku agribisnis perikanan air tawar.Data penelitian dikumpulkan dengan angket/kuesioner dan wawancara kelompok terhadap anggota kelompok pelaku agribisnis. Analisis data dilakukan dengan statistik deskriptif dan inferensial dengan Uji Rank Spearman. Hasil analisis deskriptif terhadap 284 pelaku agribisnis perikanan air tawar menunjukkan bahwa tingkat konvergensi komunikasi dalam pengembangan kapasitas tergolong rendah, ditandai dengan masih rendahnya mutu layanan informasi dan partisipasi pelaku agribisnis dalam berbagi informasi. Pengembangan kapasitas pelaku agribisnis perikanan air tawar dapat dilakukan dengan peningkatan perilaku komunikasi mengakses informasi, karena perilaku komunikasi berhubungan positif dan nyata dengan konvergensi komunikasi dalam pengembangan kapasitas pelaku agribisnis. Kemampuan kontak dengan pihak di luar komunitas dan intensitas penggunaan media merupakan bagian dari perilaku komunikasi yang berperan dalam peningkatan konvergensi komunikasi pelaku agribisnis sehingga perlu mendapat prioritas

Substantiation of the Priorities and Factors of the Formation of Competitive Advantages of the Process Industries of the Regional Agroindustrial Complex

Among the many distinctive features of the modern technical and economic situation of the reclamation industry, such as financial volatility, inconsistency of regulatory documents, there is also no effective mechanism for ensuring the country’s food security, there are flaws in the organizational, financial and credit policy, which brought down the technical level of production and technological processes ...In view of this, there is a need to mainstream a detailed study of the key problems of the agroindustrial complex (AIC) and the development of new theoretical and methodological principles and approaches to the organization of agroindustrial production. Such an approach should ensure the development of modern systems of resource-saving technologies, which will make it possible to carry out timely and deep processing of agri supplies, advance the facilities for attracting investments in priority production and agroprocessing, improve the quality and competitiveness of food and process industries, etc.The protracted transition in the agrarian sector to market relations can be explained by a narrow understanding of the essence of the market economy, measures and methods of their state regulation, which led to undesirable tendencies, ignoring national-historical features in the agrarian sector, etc., which makes it necessary to find an appropriate economic mechanism capable of guaranteeing the production of competitive products and ensuring high quality of production.On account of insufficient elaboration of many theoretical and methodological, methodical and practical aspects, the need for further research in the field of forecasting the sustainable development of the processing industry, complexity and non-systemic knowledge of the competitive functioning of the processing industries of the agroindustrial complex, we have determined its purpose and objectives

Effects of Kenaf Fibre on Fresh Properties of Fibrous Concrete

As a result of global quest for sustainable materials to achieve a bio based economy and low carbon foot print environment, the use of fibre to produce fibrous concrete composite has continuously received significant research attention. While several researches have been conducted on metallic and synthetic fibrous concretes, they exhibit several unavoidable drawbacks and bio fibrous concrete has proven to be a better alternative. Therefore, the effect of fibre volume fraction and fibre length on fresh properties of concrete was investigated. The bio fibrous concrete mix was made of six different fibre volume fractions (0.25%, 0.5%, 0.75%, 1%, 1.5% and 2%) and corresponding three different fibre lengths of 25 mm, 50 mm and 75 mm. A concrete mix proportion of grade 30 N/mm2 at 28 days target strength was prepared. A total of 19 different concrete mixes comprising of one PC mix was the control for the experiment, and 18 different mixes of Kenaf bio fibrous concrete composite (KBFCC) at varying fibre volume fraction (vf) and fibre length (lf) were tested. These mixes were tested for workability (slump, compacting factor and Vebe test) and fresh density. The slump and Vebe time for KBFCCs were 5–100 mm and 3–79 seconds respectively. The slump and Vebe time for PC were 120 mm and 3 seconds respectively. A significant drop from 0.951 to 0.809 for fibre length of 25 mm, 0.947 to 0.799 for fibre length of 50 mm and 0.931 to 0.793 for fibre length of 75 mm was observed for the compacting factor value. Though, KBFCC with fibre content below 1% was workable in spite of its low slump, its high Vebe time and low compacting factor. For fibre volume of 1% and above, the workability of concrete decreased and became very stiff with balling effect. It was seen that fresh density of PC concrete (2358 kg/m3) was higher compared to those of KBFCC (2105-2339 kg/m3), however, both values were lower than 2400 kg/m3 threshold specified by the BS code of practice. The study therefore recommended that fibre contents lesser than 1% and 50 mm length can be used in order to have good fresh properties performance