Nicholas Wambugu - Academia.edu (original) (raw)

Uploads

Papers by Nicholas Wambugu

The proposed information system will developed for local Vehicle Dealership to fulfil the need fo... more The proposed information system will developed for local Vehicle Dealership to fulfil the need for computerised record keeping of information relevant to the dealership's data processing needs. The system will comprise of various modules such as customer module, inventory module, sales module, general management module and an inquiries module. Any employee within this organization will have access rights and privileges defined commensurate with their job roles. The application will be a 32-bit Windows based program. The system analysis and design process involves the performance of relevant feasibility studies, identification of entities and objects, data flow diagrams, interface design, and information gathering, all these activities re undertaken to ensure that the system meets the particular needs of these vehicle dealer. all module within the system will allow a user can add customer's details, modify details, and update new details to records stored in the customers table. For the implementation to proceed without issues, a detailed analysis and evaluation of the current system needs to be conducted to determine its shortcomings and the conversion techniques to the proposed system. Additionally, this phase allows the system designer understand the requirements of the organization better to translate these requirements into an effective system.

Introduction Recent advances in the understanding of superhydrophobicity have led to an increase ... more Introduction Recent advances in the understanding of superhydrophobicity have led to an increase of interest regarding the introduction of super-hydrophobic materials and surfaces characterized by an exceptional ability to repel water. People's interest in super-hydrophobics has been stimulated by online videos that show individuals working through puddles of water without getting the soles of their feet wet. Therefore, this essay explains super-hydrophobic properties of surfaces and materials from an intermolecular and surface forces background. Properties of Super hydrophobic Surfaces Dynamic contact angles and Young's static are the common parameters used in explaining the wetting properties of a surface or material about water. Young's equation describes the relationship that exists between intermolecular, surface tension forces of a droplet of water, a substrate, and the droplet's vapor phase at the boundary of three states of matter: liquid, gas, and solid. Cohesive forces are responsible for maintaining the molecules of a fluid together as molecules on the outside surface of a solid exert greater pressure on one another as any other atoms do not surround them. The force exerted by these molecules comprises the surface tension and gives the liquid molecules resistance against other objects. The surface tension exhibited by an object is defined, as the force required for disintegrating a 1cm long film of a liquid. This force is expressed regarding dynes with a dyne having a value of 10µN. Therefore, for a fluid that is resting on a solid surface possesses a contact angle at the boundary between the gaseous and liquid state (Mezger et al., 2010). Accordingly, water's high surface tension allows it to form spheres of droplets when in contact with other surfaces to lessen its comparative surface and expended energy. Hence, water's contact angle is initially large but dependent on the material that water is contact. Consequently, due to water's high surface tension, it can bond with other substances if the surface is optimal. Hydrophobic surfaces and material have low surface energies that hinder them from attracting water. The contact angle between these surfaces and water molecules is greater than 90 degrees. For example, hydrophobic surfaces such as glass have a contact angle of fewer than 90 degrees resulting in water spreading over the glass (Maitra et al., 2013). Microstructured surfaces increase the tendency of a material therefore for hydrophobic the contact angle is significantly reduced whereas fro hydrophilic material the contact angle is increased. Where a materials contact angle is greater than 150 degrees, it is classed as superhydrophobic with an increase of nanoscale asperities giving the material better super-hydrophobic properties. Two of the best-known naturally occurring superhydrophobic materials are the geckos' foot and the lotus leaf. The leaf of a lotus is made up of nanoscale and microscale papillae coated with a film of wax with a contact angle of 170 degrees. As a result, this creates a self-cleaning property. Intermolecular forces depend on how electrons are distributed around different surfaces and materials (Maitra et al., 2013). Accordingly, the various forces that influence the behavior between adhesive and surface tension are categorized into four dependent on the degree of variation regarding magnitude, effective range, and sign. Van der Waals forces and hydrophobic relationships are regarded as predominate and attractive due to interaction with thousands of other nanometers of differences while the forces of electrostatic are repellent and tend to prevail in regions of the greater distance between molecules. The operative distances and magnitude of electrostatic forces reduce where there is an increase in the double layer effect. Hence, the interaction between differ polymers is characterized by the involvement of long chained organic molecules represented by a combination of various hydrophobic forces, Van der Waals, and

The proposed information system will developed for local Vehicle Dealership to fulfil the need fo... more The proposed information system will developed for local Vehicle Dealership to fulfil the need for computerised record keeping of information relevant to the dealership's data processing needs. The system will comprise of various modules such as customer module, inventory module, sales module, general management module and an inquiries module. Any employee within this organization will have access rights and privileges defined commensurate with their job roles. The application will be a 32-bit Windows based program. The system analysis and design process involves the performance of relevant feasibility studies, identification of entities and objects, data flow diagrams, interface design, and information gathering, all these activities re undertaken to ensure that the system meets the particular needs of these vehicle dealer. all module within the system will allow a user can add customer's details, modify details, and update new details to records stored in the customers table. For the implementation to proceed without issues, a detailed analysis and evaluation of the current system needs to be conducted to determine its shortcomings and the conversion techniques to the proposed system. Additionally, this phase allows the system designer understand the requirements of the organization better to translate these requirements into an effective system.

Introduction Recent advances in the understanding of superhydrophobicity have led to an increase ... more Introduction Recent advances in the understanding of superhydrophobicity have led to an increase of interest regarding the introduction of super-hydrophobic materials and surfaces characterized by an exceptional ability to repel water. People's interest in super-hydrophobics has been stimulated by online videos that show individuals working through puddles of water without getting the soles of their feet wet. Therefore, this essay explains super-hydrophobic properties of surfaces and materials from an intermolecular and surface forces background. Properties of Super hydrophobic Surfaces Dynamic contact angles and Young's static are the common parameters used in explaining the wetting properties of a surface or material about water. Young's equation describes the relationship that exists between intermolecular, surface tension forces of a droplet of water, a substrate, and the droplet's vapor phase at the boundary of three states of matter: liquid, gas, and solid. Cohesive forces are responsible for maintaining the molecules of a fluid together as molecules on the outside surface of a solid exert greater pressure on one another as any other atoms do not surround them. The force exerted by these molecules comprises the surface tension and gives the liquid molecules resistance against other objects. The surface tension exhibited by an object is defined, as the force required for disintegrating a 1cm long film of a liquid. This force is expressed regarding dynes with a dyne having a value of 10µN. Therefore, for a fluid that is resting on a solid surface possesses a contact angle at the boundary between the gaseous and liquid state (Mezger et al., 2010). Accordingly, water's high surface tension allows it to form spheres of droplets when in contact with other surfaces to lessen its comparative surface and expended energy. Hence, water's contact angle is initially large but dependent on the material that water is contact. Consequently, due to water's high surface tension, it can bond with other substances if the surface is optimal. Hydrophobic surfaces and material have low surface energies that hinder them from attracting water. The contact angle between these surfaces and water molecules is greater than 90 degrees. For example, hydrophobic surfaces such as glass have a contact angle of fewer than 90 degrees resulting in water spreading over the glass (Maitra et al., 2013). Microstructured surfaces increase the tendency of a material therefore for hydrophobic the contact angle is significantly reduced whereas fro hydrophilic material the contact angle is increased. Where a materials contact angle is greater than 150 degrees, it is classed as superhydrophobic with an increase of nanoscale asperities giving the material better super-hydrophobic properties. Two of the best-known naturally occurring superhydrophobic materials are the geckos' foot and the lotus leaf. The leaf of a lotus is made up of nanoscale and microscale papillae coated with a film of wax with a contact angle of 170 degrees. As a result, this creates a self-cleaning property. Intermolecular forces depend on how electrons are distributed around different surfaces and materials (Maitra et al., 2013). Accordingly, the various forces that influence the behavior between adhesive and surface tension are categorized into four dependent on the degree of variation regarding magnitude, effective range, and sign. Van der Waals forces and hydrophobic relationships are regarded as predominate and attractive due to interaction with thousands of other nanometers of differences while the forces of electrostatic are repellent and tend to prevail in regions of the greater distance between molecules. The operative distances and magnitude of electrostatic forces reduce where there is an increase in the double layer effect. Hence, the interaction between differ polymers is characterized by the involvement of long chained organic molecules represented by a combination of various hydrophobic forces, Van der Waals, and