928 research outputs found
Hygrothermal performance of building envelopes in the tropics under operative conditions : condensation and mould growth risk appraisal
Poor indoor hygrothermal performance increases the risk of indoor moisture problems and
deterioration due to mould growth, corrosion and damage to archival materials. Hence,
proper control of indoor thermohygric intensity abates indoor moisture and its associated
problems. This paper presents the results of envelopes hygrothermal performance
assessments in a hot and humid climate building with varying operational profile between
adjacent spaces. The case-studied building runs on 24hrs cooling mode in one part against
natural and/or mechanical supply-exhaust fan means on the other. In-situ experiments were
combined with hygrothermal analytical methods to assess the envelope thermal quality
together with the operative conditions against condensation and mould growth risks. The
results show that the building is overcooled leading to poor envelope hygrothermal
performance with associated condensation and mould growth problems on non-airconditioned sides of the envelopes
Role of membrane surface charge and complexation-ultrafiltration for heavy metals removal: a mini review
Membrane technology is a promising water purification unit operation from household use to industrial application owing to its simplicity of operation, efficient recovery and minimum need for chemical and space allocation. Due to that reason, study on the membrane applications have becoming more popular among scientific community nowadays and one of the applications is removal of heavy metal using ultrafiltration (UF). However, a stand-alone UF will be not able to carry out the removal of heavy metals effectively. Certain modification is required in order to enhance its rejection via unique facilitated mechanism. Thus in this review, role of surface charge interaction as well as the method of complexation-ultrafiltration were discussed
Generic Taxonomy of Social Engineering Attack
Social engineering is a type of attack that allows unauthorized access to a system to achieve specific objective. Commonly, the purpose is to obtain information for social engineers. Some successful social engineering attacks get victims’ information via human based retrieval approach, example technique terms as dumpster diving or shoulder surfing attack to get access to password. Alternatively, victims’ information also can be stolen using technical-based method such as from pop-up windows, email or web sites to get the password or other sensitive information. This research performed a preliminary analysis on social engineering attack taxonomy that emphasized on types of technical-based social engineering attack. Results from the analysis become a guideline in proposing a new generic taxonomy of Social Engineering Attack (SEA)
Landslides and lineament mapping along the Simpang Pulai to Kg Raja highway, Malaysia
Geological structural features, such as the discontinuities that may be detected on satellite imagery as lineaments, in many cases control landslide occurrences. Lineament may represent the plane of weakness where the strength of the slope material has been reduced, eventually resulting in slope failure. The main objective of this study is to assess the relationship between lineament and landslide occurrences along the Simpang Pulai to Kg Raja highway, Malaysia. Lineament mapping was undertaken utilizing Landsat imagery and landslide distributions were identified based on field mapping and historical records. Lineament density maps of length, number and intersections were generated and compared with landslide distributions. The lineaments were also visually compared with the landslide occurrences. The results showed that there is an association between the lineaments and landslide distribution. Thus, lineament mapping is essential for the early stages of planning to prevent hazard potential from landslides
Factors affecting endoglucanase production by Trichoderma reesei RUT C-30 from solid state fermentation of oil palm empty fruit bunches using Plackett-Burman design
A study was conducted to screen parameters affecting the production of endoglucanase by Trichoderma reesei RUT C-30 on solid state fermentation of oil palm empty fruit bunch using the Plackett-Burman design. Factors involved in the screening process were peptone concentration, urea concentration, ammonium sulfate concentration, calcium nitrate concentration, yeast extract concentration, tween 80 concentration, pH, incubation time, initial moisture content, inoculum size and substrate amount. Through analysis of variance (ANOVA), it was found that initial moisture content (p= 0.001), incubation time (p= 0.001), inoculum size (p= 0.032) and ammonium sulfate concentration (p= 0.023) have been recognized as significant factors affecting endoglucanase activity in solid state fermentation (SSF) of oil palm empty fruit bunch (OPEFB) by T. reesei RUT C-30. The model established from the ANOVA analysis have a significant value of Pmodel>F= 0.0008 and R2 of 0.9132. The preoptimized media showed 2.6 fold increased of endoglucanase activity.Key words: Cellulase, oil palm empty fruit bunches, solid state fermentation, Trichoderma reesei RUT C-30, Plackett-Burman design
Alert Correlation Technique Analysis For Diverse Log
Alert correlation is a process that analyses the alerts produced by one or more diverse devices and provides a more succinct and high-level view of occurring or attempted intrusions. The objective of this study is to analyse the current alert correlation technique and identify the significant criteria in each technique that can improve the Intrusion Detection System IDS) problem such as prone to alert flooding, contextual problem, false alert and scalability. The existing alert correlation techniques had been reviewed and analysed. From the analysis, six capability criteria have been identified to improve the current alert correlation techniques which are capability to do alert reduction, alert clustering, identify multi-step attack,reduce false alert, detect known attack and detect unknown attack and technique’s combination is proposed
A novel approach of multimedia instruction applications in engineering education
Effective use of educational technology depends on knowledge of why and how to utilize technology to solve teaching and learning problems. The present study first conducts a systematic literature review of the limited studies undertaken on multimedia instruction applications for engineering education to critique the current status of knowledge in this area. The conventional qualitative content analysis method was employed for data analysis. The results highlighted the incompatibility of three basic educational elements i.e. engineering curriculum, educational resources and engineering students’ learning characteristics all of which posed major challenges in teaching and learning engineering courses. Multimedia instruction enhances engineering students’ understanding of engineering concepts, procedures, problems and solutions through direct visualization. Furthermore, it could indirectly assist students in achieving higher order learning levels and skills through enhancing or supporting educational resources and increasing students’ motivation. Mobile multimedia instruction and a student-generated multimedia learning approach to improve engineering education are suggested for future research
A study of frequency and pulses for stepper motor controller system by using programmable logic controller
The stepper motor movement process produced different frequency and pulses. This research explained about the frequency and pulses for the stepper motor movement by using Programmable Logic Controller (PLC) as research method. The study was done to find the suitable frequency and pulses for stepper motor movement by developing a prototype stepper motor controller system. The pulse frequency used did not affected the distance of moving load in the stepper motor operations. The increasing number of pulse frequency only will affect the time taken for the stepper motor to complete its operations. The result showed that number of pulse frequency at high operation was 5000 Hz. Pulse number reacted as a manipulated variable that affected both factor which is time taken of stepper motor operation and the distance of moving load
Recognizing P2P Botnets Characteristic Through TCP Distinctive Behaviour
Botnet has been identified as one of the most
emerging threats to the Internet users. It has been attracted much attention and gives a big threat in network security.
Through the year a number of Botnet variants have been
introduced and the most lethal variants are known as peerto-
peer (P2P) botnets which able to camouflaging itself as the
benign P2P application. This evolution of Botnet variants
has made it harder to detect and shut down. Alike any
network connection, p2p similarly using TCP to initialize the communication between two parties. Based on this reason,
this paper investigates the network traffic characteristics of normal P2P connection and P2P botnets through the TCP
connection initialize or received between the bot to the bot
master. The proposed mechanism detects and classifies the
P2P botnet TCP connection behaviour from the normal P2P
network traffic. This can be used for early warning of P2P
botnet activities in the network and prevention mechanism
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