Free Essay

In: Science

Submitted By z953ss

Words 3990

Pages 16

Words 3990

Pages 16

In this era of information technology, civil engineers rely heavily on software to perform their design tasks. Unfortunately, most commercial structural analysis packages are closed-source, which means that the operations that the program performs cannot be inspected by the user.

Moreover, such software packages are invariably very pricey, and, hence, are generally not affordable for students and smaller engineering firms.

The objective of this design project was to design a structural analysis program that would be free of charge and available to all. This computer program was to be open source and well commented, so that its users could comprehend the operations performed in the analysis of a given structure.

To accomplish these objectives, the generalized stiffness method of structural analysis was implemented into a computer algorithm. This algorithm, called “TrussT Structural Analysis”, is a collection of visual basic modules embedded in a Microsoft Excel document using Visual Basic for Applications (VBA). This design report outlines the theory behind TrussT Structural

Analysis, as well as the methods by which that theory was implemented into computer algorithms. The first two sections of this report present the theory of the generalized stiffness method of structural analysis and its implementation into a computer algorithm. The following sections present the procedures by which the stiffness method was modified to incorporate the analysis of structure with special characteristics such as member applied loads, member releases or support settlements. A computer implementation of the Euler method of analysis is described to account for the geometric non-linearity of structures. Finally, algorithms that can generate member force diagrams and moment diagrams are presented.

2.0 Generalized Stiffness Method

The term stiffness refers to a body’s ability to resist imposed displacements by generating internal forces. Conversely, the term flexibility refers to a body’s ability to deflect when subjected to

6

applied forces. These two terms are analogous to two methods of structural analysis: the flexibility method, which generates compatibility equations to solve for forces, and the stiffness method, which generates equilibrium equations to solve for displacements. The preliminary report done in Phase I of this project outlined the reasons why the stiffness method is more suitable to computer implementation than its counterpart. The computer algorithm presented in this report was designed based on the stiffness method of structural analysis.

The stiffness method is based on the fundamental equilibrium equation shown in Equation 1. (1)

This equation equates force (P) to the product of stiffness (KK) and displacement (d). In the simplest terms, this equation represents the equilibrium between external forces and internal forces. In terms of a structure, the applied joint forces (P) and joint displacements (d) are vectors, whereas the structure stiffness is expressed as a matrix of n-by-n terms, n being the degrees-of-freedom of that structure. Generally, both the applied forces (P) and the structure’s stiffness (KK) are known, which leads to a system of n equations with n unknown joint displacements (d).

3.0 Computer Implementation of the Stiffness Method

The analysis engine driving TrussT Structural Analysis is a computer implementation of the stiffness method. This section describes the basic approach that was taken to implement the stiffness method in a computer program. That implementation as utilized in TrussT Structural

Analysis is illustrated in Figure 1.

7

Obtain Input Parameters

Organize Inputs in Arrays

(Record Keeping)

Calculate Member Stiffnesses (s)

Assemble Global Stiffness Matrix (K)

Solve for Global Displacements (d)

Transform Displacements to

Local Coordinates (u)

Calculate Member Forces (Q)

Transform Member Forces to

Global Coordinates (F)

Assemble Reaction Forces (R)

User Inputs

Joint

Displacements

Reaction

Forces

Figure 1: Analysis Procedure Flow Chart

3.1 Input

TrussT Structural Analysis requires information about the structure to be inputted by a user in three parts: joint inputs, member inputs, and load inputs. Appendix A of this report presents a user’s manual, which outlines how to use the program and input the necessary variables.

The variables required by the program to analyse a structure are described in following subsections. Consistent units must be used when inputting information in the user interface.

Although the user interface suggests the metric units of mm, kN and GPa, any set of consistent units will produce correct results (e.g. in, kips and ksi).

3.1.1 Joint Inputs

For each joint, the program requires:

Joint Coordinates - numerical values for the three dimensional coordinates (x, y, z).

8

Joint Boundary Conditions – indicating whether translations and rotations are free or restrained along the x, y, and z axes. Alternatively, the user can specify whether a joint is fixed, pinned or free.

3.1.2 Member Inputs

For each member, the program requires:

Member Joints - the two joints the member spans.

Member Orientation (ψ) – defined as either (1) for general members or (2) for vertical members. (1) The angle, measured clockwise positive, when looking in the negative x direction, through which the local xyz coordinate system must be rotated around its x-axis so that the xy plane is vertical with the y-axis pointing upwards.

(2) The angle, measured clockwise positive, when looking in the negative x direction, through which the local xyz coordinate system must be rotated around its x-axis so that the z axis is parallel to, and points to global z.

Member Section Properties – modulus of elasticity E, area A, shear modulus G, moment of inertia about the strong axis Iz, moment of inertia about the weak axis Iy, and the torsion constant J.

3.1.3 Load Inputs

For each load the program requires the:

Load Location – the joint on which an external load is applied.

Load Magnitude – numerical value of the load (force and moment) in each axis.

3.2 Record Keeping

In order to organize adequately all the input and output information in a set of matrices, the program assigns record-keeping indices to every joint translation and rotation. These indices, later referred to as codes, represent the position of a certain joint displacement or reaction in the

9

global vectors and matrices presented in Equation 1. In three dimensions, each joint has six possible movements (translations and rotations about each of the x, y, and z axes). The computer program first assigns codes to the joint movements that are free, that is, joint movements that are not boundary conditions. The total number of such movements is referred to as the degrees-offreedom of the structure. Once all the degrees-of-freedom have been assigned codes, the computer program then assigns codes to the joint movements with boundary conditions.

3.3 Member Stiffness

Based on the inputted member properties, the program generates a 12 x 12 member stiffness matrix (s ss) and transformation matrix (T TT) for each member. Equation 2 illustrates the local stiffness matrix for a space frame element based on the member properties, while Equation 3 shows the transformation matrix required to transform the member’s stiffness matrix into the structure’s coordinate system.

(2)

(3)

…where (rrr) is given by Equation 4 for general members and by Equation 5 for vertical members.

10

(4)

(5)

The member stiffness matrix (s ss) for each member is converted from the Local Coordinate

Systems (LCS) into the Global Coordinate System (GCS) through Equation 6, which yields the member stiffness matrix in the GCS (k kk). k (6)

3.4 Global Stiffness

A structure’s global stiffness (KK) consists of a n-by-n matrix of coefficients, where n represents the degrees-of-freedom of the structure. To assemble (KK), the program uses the codes assigned in the record keeping phase to assemble the individual member stiffness matrices to the global stiffness matrix.

3.5 Determining Displacements

The joint displacements at the free degrees-of-freedom (d) are computed using the joint equilibrium equation, Equation 1, which relates these displacements to the known applied joint loads vector (P) and to the known structure’s global stiffness (KK). A Gauss-Jordan solver is used to solve for these member displacements.

11

3.6 Converting Displacements to Local Coordinates

Once the displacements in the GCS (d) are determined, they are stored as the member end displacements (v) using the record keeping codes. These global displacements are then converted to the LCS through the member transformation matrices, as shown in Equation 7. (7)

3.7 Calculating Member Forces

Once the joint local member displacements (u) are known, the algorithm calculates the member forces (Q) based on the member’s local stiffness matrix (s ss) with Equation 8. Equation 8 is the member-space equivalent of the basic equilibrium equation, Equation 1. (8)

3.8 Transformation of Member Forces

The member forces in LCS (Q) are transformed back to the GCS using Equation 9, at which point they are assembled based on the structure’s configuration (using the record keeping codes) to obtain the global reactions. (9)

3.9 Computer Algorithm

The following pseudo-code outlines the stiffness method presented in this section to solve for a framed structure under joint loads. The nomenclature of the variables and the procedures used are described following the code.

'Assembly of Applied Loads Vector (P)

Loop i = 1 To numNodes

M1() = GetCodes(Node(i))

M2() = GetForces(Node(i))

Loop j = 1 To 6

P(M1(j)) = M2(j)

End Loop

End Loop

12

‘Assembly of Member Stiffness Matrix (S) and Transformation Matrix (T); Performed in Member Class

Module for each member

S_local() = MemberStiffness(E, A, L, Iy, Iz, J)

T() = Transformation(x1, x2, y1, y2, z1, z2)

S_global() = Transpose(T()) * S_local() * T()

'Assembly of Structure’s Stiffness Matrix (K)

Loop i = 1 To numMem

M1() = GetCodes(Member(i))

M2() = GlobalStiffness(Member(i))

Loop j = 1 To 12

If M1(j) minDOF Then

P(M1(j)) = P(M1(j)) + M2(j)

End If

End Loop

End Loop

Description of Variables and Procedures

M1() - Temporary matrix

M2() - Temporary matrix numNodes – Number of nodes in the system numMem – Number of members in the system

S_local() - Local member stiffness

S_global() - Global member stiffness matrix

K() - Structure’s overall stiffness matrix

Kff() - Structure’s partitioned stiffness matrix for free nodes

E, A, Iy, Iz, J – Member properties specified by the user

L – Member length

T() – Member transformation matrix x1, x2, y1, y2, z1, z2 – Member coordinates minDOF – Number of degrees-of-freedom in the system

P() - Joint forces vector

Q() - Member forces vector in local coordinates

F() - Member forces vector in global coordinates u() - Nodal displacements vector in local coordinates

D() - Nodal displacements vector in global coordinates

Node(i) - Class module for node i

13

Member(i) - Class module for member i

Getcodes - Invokes code number stored in the class module.

GetForces - Invokes user-specified load stored in the class module.

MemberStiffness - Calculates the member stiffness matrix using Equation 2.

Transformation - Calculates the member transformation matrix using Equation 3.

MemberStiffness - Invokes the member stiffness in the global coordinate system stored in the class module.

MemberForce - Invokes the member forces stored in the class module.

Transpose - Performs transposed matrix operation.

MatInv - Performs inverse matrix operation.

4.0 Equivalent Joint Loads

As the basic stiffness method considers only loads applied at the joints, the concept of Equivalent

Joint Loads (EJL) can be used to expand the scope of the stiffness method to include member loads. To determine the EJL of a structure, the EJL of each member must be determined and assembled using the record-keeping codes. Kassimali [1] and others have shown that these EJLs are equivalent to the negative of the fixed-end forces generated by a set of loads on a fully fixed member. Fixed-end forces for a member subjected to any set of loads can be found based on the already derived formulae found in many structural analysis textbooks, such as Kassimali [1]. The equations used in TrussT Structural Analysis to solve for the fixed-end forces are included in

Appendix B. TrussT Structural Analysis has the capability of converting member point loads and linearly variable distributed loads to equivalent joint loads. No formula could be found in available literature that described the fixed-end forces caused by a linearly variable axial load.

Therefore, a formula was derived for linearly variable axial loads based on the axial point load formula presented by Kassimali [1]. The derivation of this can be found in Appendix B.

The fixed-end forces are assembled from local coordinates (Qf) to global coordinates (Pf) using the same coding mechanism used to assemble the structure’s stiffness matrix.

The equivalent joint loads are incorporated in the procedure described in section 3 by subtracting the fixed-end forces (adding the EJL) from the applied joint loads. This operation is integrated into the analysis by modifying Equations 1 and 8 to Equations 10 and 11. (10) (11)

14

The following pseudo-code illustrates the conversion of member loads to equivalent joint loads in

TrussT Structural Analysis.

If bDist = False Then

R() = PointLoad(L, Pos, sForces(3))

EJL(3) = EJL(3) + R(1)

EJL(5) = EJL(5) + R(2)

EJL(9) = EJL(9) + R(3)

EJL(11) = EJL(11) + R(4)

R() = PointLoad(L, Pos, sForces(2))

EJL(2) = EJL(2) + R(1)

EJL(6) = EJL(6) + R(2)

EJL(8) = EJL(8) + R(3)

EJL(12) = EJL(12) + R(4)

R() = AxialLoad(L, Pos, sForces(1))

EJL(1) = EJL(1) + R(1)

EJL(7) = EJL(7) + R(2)

R() = Moment(L, Pos, sForces(6))

EJL(2) = EJL(2) + R(1)

EJL(6) = EJL(6) + R(2)

EJL(8) = EJL(8) + R(3)

EJL(12) = EJL(12) + R(4)

R() = Moment(L, Pos, sForces(5))

EJL(3) = EJL(3) + R(1)

EJL(5) = EJL(5) + R(2)

EJL(9) = EJL(9) + R(3)

EJL(11) = EJL(11) + R(4)

R() = Torque(L, Pos, sForces(4))

EJL(4) = EJL(4) + R(1)

EJL(10) = EJL(10) + R(2)

Else

R() = Distributed(L, Pos1,Pos2, sForces(5), sForces(6))

EJL(3) = EJL(3) + R(1)

EJL(5) = EJL(5) + R(2)

EJL(9) = EJL(9) + R(3)

EJL(11) = EJL(11) + R(4)

R() = Distributed(L, Pos1,Pos2, sForces(3), sForces(4))

EJL(2) = EJL(2) + R(1)

EJL(6) = EJL(6) + R(2)

EJL(8) = EJL(8) + R(3)

EJL(12) = EJL(12) + R(4)

R() = AxialDistributed(L, Pos1, Pos2, sForces(1), sForces(2))

EJL(1) = EJL(1) + R(1)

EJL(7) = EJL(7) + R(2)

End If

Description of Variables and Procedures bDist - Identifier for distributed loads sForces() - Member load vector

( sForces(1) = Fx; sForces(4) = Mx for point loads )

( sForces(1) = Fx1; sForces(2) = Fx2 for distributed loads )

L - Member length

Pos - Location of point load

Pos1 – Location of near-end distributed load

Pos2 – Location of far-end distributed load

R() – Temporary matrix to store computed equivalent joint load for the member load being considered.

EJL() – Equivalent joint load vector

15

PointLoad - Converts point member load to equivalent joint load.

AxialLoad - Converts point axial load to equivalent joint load.

Moment - Converts applied moment to equivalent joint load.

Torque - Converts torque to equivalent joint load.

Distributed - Converts distributed load to equivalent joint load.

AxialDistributed - Converts distributed axial load to equivalent joint load.

*Equations used for the above sub-function are included in Appendix B

5.0 Member Releases

TrussT Structural Analysis has the ability to account for member releases in a structure. A member is said to be released at a certain location when its ability to develop an internal force at that location has been removed. Physical examples of member releases are hinges (rotational releases) and slotted connections (translational releases). Figure 2 depicts the possible locations of member releases on a space frame member.

Figure 2: Possible Locations of Member Releases

Releases at intermediate locations along the member can also be modeled using the approach outlined below by utilizing two smaller members and releasing the joining ends.

To account for a member release, one must modify the basic equilibrium equations to ensure that the force at the location being released is zero. That is, if one is to release the translation at #3, then the internal force Q3 in Equation 11 must be set to zero. Setting Q3 equal to zero implies that the right-hand side of the Q3 equilibrium equation is also zero, as shown in Equation 12. (12)

Equation 12 shows that there is inter-dependence between the set of member displacements.

Equation 12 can therefore be re-written as Equation 13. … / (13)

16

The stiffness matrix needs to be modified to reflect the physical reality of the member release.

Given that Q3 = 0, any set of displacements (u) will cause Q3 to remain 0. Therefore, the third row of the member stiffness matrix should be a row of zeros. As Equation 14 shows, the equilibrium conditions now consist of 11 equations containing 12 unknown displacements.

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

(14)

Given that there is one too many unknowns for this system of equations to be solvable, the displacement u3 must be distributed to the other displacements according to Equation 13.

Additionally, as Equation 13 shows, the released displacement u3 also depends on Qf3, the member local fixed-end force at location #3. Therefore as u3 is being substituted into the other rows of the stiffness matrix, the fixed-end forces corresponding to this row must also be modified according to Equation 12.

The final element stiffness matrix will be an 11 x 11 matrix. This released matrix can also be thought of as a 12 x 12 matrix with a row and column of zeros. The row of zeros signifies that no force can be generated at that location regardless of the member displacements, and the column of zeros is necessary to have a solvable system of equations. The effect of that displacement has been expressed as a sum of other displacements and fixed-end forces, and the stiffness and member fixed-end forces coefficients have been modified accordingly.

The following procedure is analogous to how TrussT Structural Analysis implements the member release procedure.

1. Determine location to be released (r)

2. Express ur as the sum of other displacements:

17

3. For every ij element of the stiffness matrix, subtract the following stiffness according to

Equation 12:

4. Similarly, for the each i fixed-end force, subtract the following force according to

Equation 12:

5. Set all ri elements of the stiffness matrix equal to zero: 0

6. Set all ir elements of the stiffness matrix equal to zero: 0

The complete algorithm for this process can be found in the cMember class module of the program code, under the sub-procedures ReleaseMatrix and ReleasedQF. TrussT Structural

Analysis uses the above procedure to transform the space frame stiffness matrix into various released matrices. Instead of having different algorithms to solve for the displacements of trusses, beams or other simplified structures, TrussT uses member releases to transform the space frame stiffness matrix to the desired simplified matrix. As Equation 15 shows, a space frame stiffness matrix released 10 times at r = 2, 3, 4, 5, 6, 8, 9, 10, 11, and 12 is equivalent to a 2 x 2 axial member stiffness matrix.

18

(15)

6.0 Support Settlement

The alternative formulation of the stiffness method, as presented by Kassimali [1], is particularly well suited to the incorporation of a support settlement into the analysis of a structure. This method involves assembling a global stiffness matrix (KK* **) of size m-by-m, where m represents not only the quantity of degrees-of-freedom, but the total quantity of degrees in the structure.

This method also involves assembling an m sized applied load vector (P*), fixed-end forces vector (Pf*) and global displacement vector (d*). The resulting equilibrium is shown in Equation

16.

(16)

Equation 16 is particular in the way that it has unknowns on both sides of the equation. To solve such a system, Kassimali’s proposed partitioning the KK* ** matrix into four sub-matrices and partitioning the P*, Pf* and d vectors into two sub-vectors each as follows:

(17)

(18)

(19)

(20)

19

…where dR is the vector of known support settlement and PR is the vector of unknown applied loads (support reactions).

The KK and KKF FFR RR sub-matrices are used to compute the joint displacements (d) as per Equation 21, whereas the KKR RRF FF and KKR RRR RR sub-matrices are used to compute the unknown reactions forces (PR) as per Equation 22. (21) (22)

Although this formulation requires larger matrices, it allows for the unknown global reactions to be solved directly, without using the assembly process described by Equation 9.

One drawback of this method of analysis arises when conducting second-order analyses (as discussed in Section 7). Since second-order analyses required the computation of the member forces, it was found not to be computationally advantageous to compute reaction forces as per

Equation 22. Second-order analyses require that the systems of equations be solved numerous times, therefore the reduction of the number of operations within the loop of iterations will drastically reduce the overall computation time.

For that reason, a hybrid between Kassimali’s alternative formulation and the original formulation was adopted by TrussT Structural Analysis, whereby the global displacements are computed by Equation 21, and the support reactions are computed as before, by assembling the member forces (F). Therefore, Equation 22 is not utilized in the TrussT Structural Analysis algorithm. It should be noted that a structure with no support settlement has a (dR) displacement vector of 0; therefore, Equation 21 reverts to its original form in Equation 10.

20

7.0 Second-Order Analysis

In first-order analysis, it is assumed that the load-displacement relationships of structural elements are linear, such that the linearly-assumed displacements under an increasing applied load (P) will deviate from the actual displacement, as shown in Figure 3.

Figure 3: Equilibrium Paths of Linear and Nonlinear Analyses

As Figure 3 illustrates, the discrepancy between the assumed displacements and the actual displacements grows enormously as the applied load increases.

Second-order analysis involves continuously or intermittently changing the stiffness of a structure so that it responds to applied loads based on its current configuration, rather than based on its initial configuration. This procedure more accurately models the displacement behaviour of an element. TrussT Structural Analysis has a function that incorporates geometric nonlinearity into the analysis. The algorithm is based on the Euler method, also known as the incremental single-step method. The Euler method is the most elementary second-order analysis method; however, it is suitable for solving a system with moderate nonlinearity, which applies to most structural engineering applications. Figure 4 illustrates an element equilibrium path using second-order analysis based on the Euler method alongside the actual equilibrium path.

21

Figure 4: Euler method second-order iteration

As Figure 4 illustrates, the actual equilibrium path of an element is more accurately modelled with the Euler method than with first-order analysis. Furthermore, as the number of iterations increases, the linear segments outlining the equilibrium path will become shorter and the accuracy of the model will increase.

In the program, once the user chooses to perform a second-order analysis, the user may also specify the number of iterations (n). The prescribed loads are then discretized into n incremental loads (ΔP). The program performs n linear analyses that are analogous to the first-order analysis, described in sections 2 and 3, to calculate the incremental displacements (Δu) and the member forces (ΔQ). The second-order analysis is different from the first-order analysis in the sense that it uses the tangent stiffness matrix (Kttt), which is the sum of the elastic stiffness matrix (K) and the geometric stiffness matrix (Kggg). The member geometric stiffness matrix is given in Equation

23.

22

(23)

As shown in Equation 23, the member geometric stiffness matrix is a function of the member axial force (Fx2), hence, the geometric stiffness (and the tangent stiffness) will change as the nodal displacements change along the iteration. Once the iteration is complete, the calculated incremental displacements and member forces

Premium Essay

...Implementing Empowerment in an IT Organization By Student X GM591: Leadership and Organizational Behavior Dr. Ron Stone Keller Graduate School of Management Introduction 3 Problem Statement 5 Literature Review 5 Causes 14 Solutions 16 Reflection 19 Appendix 21 Introduction The organization I chose to study is Software Engineering (SE) in the Internal Information Services (IIS) unit of Defense Contractor X’s Information Technology (NGIT) Sector. The mission of the organization is to conceive, develop and maintain software engineering solutions for the IT Sector of Defense Contractor X. SE is comprised of a Director, Tens Level Managers, Unit Level Manager, Team Leads and Software Engineers. The Director and Tens Level Managers have three to eight people reporting to them. The Unit Level Managers have from fifteen to twenty people reporting to them. In order to manage such large numbers of people, the Unit Level Managers are encouraged to empower their employees to take ownership of their jobs. The Team Lead role is used as a substitute for a Unit Level Manager, with increased responsibilities, but there is no increase in pay or grade when someone assumes the job. Often managers use the Team Lead role to groom future managers of NGIT. Many of the Team Leads are motivated, self-directed individuals who have a certain amount of autonomy in their current roles, which pre-disposes them for managerial work in the......

Words: 4539 - Pages: 19

Free Essay

...basis for seismic design. Key Words: Classroom Buildings, Seismic Appraisal, Reinforcement . Introduction In the 2008 Sichuan Earthquake, numerous buildings in the stricken area fell down, and many people died. As primary and high schools were generally located in heavily traveled high populated areas, Classroom Buildings in them were public ones with very high population density. So if a building collapsed, a considerable number of students and teachers would die and a large amount of property would be damaged. After the Earthquake, the State Council and the Ministry of Education immediately orders local governments to undertake an earthquake resistance appraisal of each building in each primary and each high school, and to take corrective measures with regard to the buildings that failed to meet the earthquake resistance standards correspondingly. In response thereto, in September 2009, the Education Committee of Shapingba District of Chongqing Municipality entrusts Chongqing Chen Ceng Architectural Engineering Design Company to undertake earthquake resistance appraisals on the Classroom Buildings in all primary and high schools in the District. Considering the urgent need from the government and the people, our group made good use of the "Third College Students Scientific Research...

Words: 3986 - Pages: 16

Premium Essay

...Contemporary research of the digital divide and digital skills is marked by a descriptive nature. Inequalities are described using simple demographics of individuals who have more or less access to computers and the Internet and a different level of digital skills. The explanation of these differences has far less attention. One of the reasons for this state of affairs is the predominance of individualistic notions of inequality. Like most social scientific and economic investigations, digital divide research works on the basis of so-called methodological individualism (Wellman & Berkowitz, 1988). Differential access to information and computer technologies (ICTs) is related to individuals and their characteristics: level of income and education, employment, age, sex, and ethnicity, to mention the most important ones. This is the usual approach in survey research, which measures the properties of individual respondents. Making multivariate analyses of several individual properties and aggregating them to produce properties of collectivities, one hopes to find background explanations. This kind of research might produce useful data, but it does not automatically result in explanations, as it is not guided by theory or by hypotheses derived from theory. They remain on a descriptive level of reasoning. One is not able to explain, for example, what it is about age and gender that produces the differences observed. Another disadvantage of the individualistic approach to......

Words: 2142 - Pages: 9

Premium Essay

...“Education is what survives when what has been learned has been forgotten” -B.F. Skinner Behaviorism is described as a developmental theory that measures observable behaviors produced by a learner’s response to stimuli. Responses to stimuli can be reinforced with positive or negative feedback to condition desired behaviors. Punishment is sometimes used in eliminating or reducing incorrect actions, followed by clarifying desired actions. Educational effects of behaviorism are key in developing basic skills and foundations of understanding in all subject areas and in classroom management. According to behaviorism, knowing is giving the correct response when exposed to a particular stimulus. The behaviorist is not concerned with how or why knowledge is obtained, but rather if the correct response is given. Yu Ching Chen’s web site on behaviorism states that, “Learning is defined as nothing more than the acquisition of new behavior”. In terms of the concept of learning, the process tends to be passive with regard to the behaviorist theory. The learner uses low level processing skills to understand material and the material is often isolated from real-world contexts or situations. Little responsibility is placed on the learner concerning his/her own education. Typical classroom instruction consistent with the behaviorist theory includes; classroom management, rote memorization, and drill and practice. Several examples of behaviorism used in classroom......

Words: 938 - Pages: 4

Free Essay

... Stanley L. Sclove [pic] The Sears, Roebuck Case These notes Copyright © 2005 Stanley Louis Sclove [pic] HyperTable of Contents 0. Introduction; Key Terms 1. What is Structural Equation Modeling? 2. A Simple Example of SEM 3. The Role of Theory in Structural Equation Modeling 4. Developing A Modeling Strategy 5. Estimating a Path Model with Structural Equation Modeling References [pic] 0. Introduction; Key Terms Preview In this course we consider Structural Equation Models. This note anticipates much material which will be discussed in more detail in the course or in the text (Schumacker and Lomax 2004). The note is based on a Harvard case, together with an example from Hair et al. and some introductory material. Key Terms The diagrams used in SEM are called path diagrams. The response variables are endogenous; the explanatory variables, exogenous. The modeling proceeds in terms of concepts, represented by constructs, measured by variables called indicators of the constructs. The model relating the indicators to the constructs is called the measurement model. The model relating the constructs to one another is called the structural model. [pic] 1. What is Structural Equation Modeling? Structural equation models (SEMs) include path analysis and factor analysis. SEMs include the econometrician's Simultaneous Equations Models. However, SEMs may include unobserved ("latent")......

Words: 2002 - Pages: 9

Premium Essay

...The Surprising Foil to Online Education: Why Students Won’t Give Up Paper Textbooks Joanne McNeish, Mary Foster, Anthony Francescucci, Bettina West Purpose of the Study. Digital resources are an integral part of online education. Although advocates of digitized information believe that millennial students will embrace the paperless classroom, this is not proving to be the case. This research addresses gaps in our understanding of student resistance to giving up paper-based learning resources by examining attributes of the paper textbook that are perceived as necessary for knowledge transfer and that are not present in digital information modalities. Method/Design and Sample. Phase 1 used focus groups to identify the content of items that were incorporated into a quantitative instrument in phase 2. A sample of 386 undergraduate students taking marketing courses at a Canadian urban university completed the online survey. We then used Confirmatory Factor Analysis to test the factors linked to resistance to discontinuing paper textbooks. Results. Students’ resistance to giving up the paper textbook positively relates to the way in which the paper textbook facilitate learning and study processes, is permanent and under the students’ control during and after the course is finished. The fluid and dynamic nature of digital content compared to the more consistent and predictable nature of information on paper appears to be a barrier to the acquisition of knowledge for the purpose of...

Words: 4886 - Pages: 20

Free Essay

...Louisiana Tech University, I serve as the President Elect for the North American Society for Trenchless Technology, and was previously Secretary and Treasurer for the Associated General Contractors of America. As part of the required curriculum as a degree candidate, I have successfully excelled in a variety of courses such as: Statics and Mechanics of Materials, Principals of Structural Analysis, and Principals of Hydraulic Engineering Systems. In addition to the engineering design courses, I have successfully taken multiple business related courses such as: Business Management, Principals of Accounting, and Introduction to Marketing. I have extensive experience and training in many fields of the construction industry. My most recent experience as a Truss Design Engineer involves in- depth analysis of truss systems and components, as well as all aspects of structural framing. Prior to this experience, I was employed at Rimcor, Inc. which involved working in paper mills. I have numerous hours of safety training and understand the importance of safety. As a result of my employment history and education, I have become proficient in multiple Microsoft programs such as: Excel, Word, and...

Words: 369 - Pages: 2

Premium Essay

...The 11th International Scientific Conference eLearning and software for Education Bucharest, April 23-24, 2015 10.12753/2066-026X-15-081 HEALTH-RELATED IMPACT, ADVANTAGES AND DISADVANTAGES OF ICT USE IN EDUCATION, COMPARED TO THEIR ABSENCE IN THE PAST Paruyr HARUTYUNYAN, Alin MOLDOVEANU, Florica MOLDOVEANU Faculty of Automatic Control and Computer Science, University Politehnica of Bucharest, Splaiul Independentei 313, sector 6, Bucharest, Romania par0308@gmail.com, alin.moldoveanu@cs.pub.ro, florica.moldoveanu@cs.pub.ro: Victor ASAVEI Faculty of Automatic Control and Computer Science, University Politehnica of Bucharest, Splaiul Independentei 313, sector 6, Bucharest, Romania victor.asavei@cs.pub.ro Abstract: Society has been very quick to adopt and master computer, as well as latest mobile technologies as an integral part of its everyday life. Innovative technologies have penetrated into nearly every aspect of human life and are now so much involved and embedded in social life that most people do not even realize that these technologies are relatively new inventions. Furthermore, nowadays people do not imagine their daily life without technology. In fact, information technologies create great comforts for humans in their everyday life. Despite that, one cannot say for sure that technology has only positive impact on physical, mental or psychological state of humans. Now we are living in the era of digital technologies, where scientists put forward...

Words: 3976 - Pages: 16

Premium Essay

...http://arthurwilson.vze.com http://www.turbosquid.com/Beta/Search/Index.cfm?keyword=arthurwilson3rd BACKGROUND: Over 20 years of practical work experience and on the job training in the engineering field. Experienced, capable and innovative mechanical designer with record of effective participation and leadership in vitally important and complex projects Demonstrated management competence and broad engineering comprehension by coordinating diverse mechanical engineering ,mechanical design and design drafting disciplines to effect optimum results in adhering to completion schedules and maintaining high quality, safe design and construction relating to the aerospace and defense industry per ANSI-Y-14.5 & DOD-D-100/DOD-STD-1000. EDUCATION: 1980 - 1983 Los. Angeles Trade Technical College Major Course of Study and Details of Classes Mechanical Design Drafting Computer Aided Drafting Tech. Illustration College Level Mathematics Mathematics for engineers ANSI-Y-14.5 Geometric Tolerances and Dimensioning Tolerance analysis and application in design/manufacturing practice. Tolerance specification analysis ANSI and ISQ standards, geometry through geometric dimensioning and tolerance Materials selection in mechanical design: Selecting materials for engineering applications. The major families of materials, their properties, and how their properties are controlled; case studies and design projects emphasizing materials selection. Programming for......

Words: 3044 - Pages: 13

Free Essay

...Kingsford Smith Drive Upgrade Mahdi Mohammad (n9428691) Queensland University of Technology Table of Contents ABSTRACT 3 1.0. INTRODUCTION 3 2.0. NEED FOR THE INITIATIVE 5 3.0. INITIATIVE’S LIFECYCLE 5 Initial Planning 6 Procurement 7 Design 9 Development 10 Delivery 11 Operation and Maintenance 11 Retirement 13 Civil Engineering Research 13 4.0. CIVIL ENGINEERING SYSTEM 15 5.0. STEWARDSHIP OF THE INITIATIVE 16 6.0. VALUES REGARDING THE INITIATIVE 16 Economic 16 Social 17 Sustainability 17 Political 18 7.0. ONLINE DISCUSSION FORUM REVIEW 19 8.0. CONCLUSIONS AND INFORMED POSITION 20 Conclusions 20 Informed Position 20 ACKNOWLEDGMENTS 21 REFERENCES 22 ABSTRACT The Brisbane City Council is embarking on the project of completing the staged upgrade of Kingsford Smith Drive to decrease traffic congestion and advance safety on the busy road. The Kingsford Smith Drive is a major lane connecting Brisbane CBD to the Brisbane Airport, Port of Brisbane, North-shore Hamilton, and the Australia Trade Coast area. The road was called after the aeronaut Charles Kingsford Smith. It links the suburb of Pinkenba to the Brisbane central business district at the Breakfast Creek. The Roadis categorized as a primary freight route. The demand for transportation of freight on Kingsford Smith Drive is anticipated to grow promptly. Construction of the phase one of the projects that widened a portion of Kingsford Smith Drive from four to six lanes was accomplished in......

Words: 4730 - Pages: 19

Premium Essay

...CHALLENGES FACING E-LEARNING (ELECTRONIC LEARNING) IN TEACHING BUSINESS EDUCATION COURSES: STRATEGIES FOR IMPROVEMENT BY JIMOH-KADIRI SIDI OSAMUEDE (MRS.) AND BUPO GODWIN OMONI Dept of Vocational Education, Nnamdi Azikiwe University, Awka BEING A PAPER PRESENTED AT THE ANNUAL NATIONAL CONFERENCE (THEME: E-LEARNING IN NIGERIA: PROBLEM AND PROSPECTS) ORGANISED BY THE FACULTY OF EDUCATION, NNAMDI AZIKIWE UNIVERSITY, AWKA. 31ST AUGUST – 3RD SEPTEMBER, 2010. CHALLENGES FACING E-LEARNING (ELECTRONIC LEARNING) IN TEACHING BUSINESS EDUCATION COURSES: STRATEGIES FOR IMPROVEMENT Abstract Electronic learning (e–learning) which is one of the by-products of information and communication technology has changed many aspects of life and opened a wide vista of opportunities for people. This paper discusses the challenges facing e-learning in teaching business education courses. The need for e-learning in business education is also discussed. Subsidized or free in-house computer literacy training programmes for business teachers and students and provision of adequate info-tech facilities to academic Institutions are among the recommendations made for improvement in the teaching and learning of Business Education courses through e-learning technology. Introduction One challenge that faces the profession and practice of business education and indeed the whole of mankind is the progress and innovation offered by technological developments since mid 1990s. The emergence of information and......

Words: 3593 - Pages: 15

Premium Essay

...Business Development in a Network Perspective Case Analysis Assignment October, 2013 Identifying challenges and bottlenecks based on theoretical review ESRI had a software product used for geographic information systems (GIS): ArcInfo. Listening to its customers, investing in new technology and aligning it to real customer needs were key factors that contributed to ESRI becoming world’s leading vendor of GIS in terms of revenue, market share and innovation. Here, ESRI had a successful business market process in which effort was put in understanding its customers’ needs (market sense), and creating (managing market offerings) as well as delivering value (sustaining customer relationship). However, with the arise of the desktop GIS, a new type of GIS users emerged. Their demands were different than the traditional GIS users because they didn’t need specialized, hard-to-use software. In terms of Anderson and Narus (2004), ESRI needed to understand the value of these new customers (market sense), in order to anticipate on this ‘new demands’ (crafting market strategy and in the end, gaining customers). This led to the launch of desktop GIS technologies (new offering realization). Along with the adoption of the Internet into the world of GIS, ESRI re-engineered its entire product line into a “platform”, called ArcGIS. Google and Microsoft challenged the market segment by investing in virtual globes. Now being available for free for the mass and with the upcoming......

Words: 3014 - Pages: 13

Free Essay

...Relationship of Centralization to Other Structural Properties Paper citation: Jerald Hage and Michael Aiken, “Administrative Science Quarterly” Vol. 12, No. 1 (Jun., 1967), pp. 72-92 Group AC2: Ankit Kumar Baranwal (14F506) Ashish Girdhar Gyanchandani (14F513) Charu Pandey (14F516) Natesh Bhardwaj H S (14F535) Surya Bakshi (14F550) 1 Overview In the article titled “Relationship of Centralization to Other Structural Properties”, Jerald Hage and Michael Aiken talk about two different ways of measuring distribution of power. They collect data by conducting survey in 16 hospitals and welfare organizations of which 10 are private and 6 are public. The purpose of this article is to explore the relationship between centralization of power and two critical aspect of organizational social structure, namely; the degree of formalization and the degree of complexity. Here, Hage and Aiken measure the degree of complexity using three factors, namely; the number of occupational specialties, the amount of professional training and professional activity while on the other hand the degree of formalization is being measured in terms of degree of job codification and the amount of rule observation. The author Jerald Hage is a Professor Emeritus and Co-Director of Center for Innovation, University of Maryland. He completed his Bachelor of Business Administration (B.B.A.), marketing from University of Wisconsin and Doctor of Philosophy (PhD) in sociology......

Words: 2055 - Pages: 9

Premium Essay

...Dynamic, and Implementation…....................................12 4+1 View of UML Diagrams……………………………………………………………………13 Object-oriented Class Model and Relational Database Model..............................................…...14 Use of UML to develop Ontologies…………………………………………………………..…17 References……………………………………………………………………………………….19 Abstract The Unified Modeling Language (UML) is being used as the de-facto standard in the software industry. With the adoption of UML 2.0, the new enhancements allow this version to describe many of the elements found in today's software technology as well as Model Driven Architecture and Service-Oriented Architecture. Many existing software applications involve complex application layer implemented in object-oriented programming languages and at the same time use relational database systems as the back-end data store. Modeling the whole system in a consistent manner will help developers and end users better understand the application. The Unified Modeling Language (UML) is a standard language for modeling software and database systems. Data model of object-relational databases (ORDBs) is a great challenge to many database applications due to its complexity. UML offers tremendous flexibility and rich expressivity for modeled ORDB system. This paper shows how to model relational database using UML, how to extend the UML meta-model with elements for modeling relational dependencies, and also presents techniques...

Words: 3708 - Pages: 15

Free Essay

...This article was downloaded by: [La Trobe University] On: 16 January 2013, At: 18:29 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Computers in the Schools Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/wcis20 Instruments for Assessing the Impact of Technology in Education Rhonda Christensen & Gerald Knezek a a b Institute for the Integration of Technology into Teaching and Learning (IITTL), University of North Texas, P.O. Box 311337, Denton, TX, 76203, USA b University of North Texas, P.O. Box 311337, Denton, TX, 76203, USA Version of record first published: 11 Oct 2008. To cite this article: Rhonda Christensen & Gerald Knezek (2001): Instruments for Assessing the Impact of Technology in Education, Computers in the Schools, 18:2-3, 5-25 To link to this article: http://dx.doi.org/10.1300/J025v18n02_02 PLEASE SCROLL DOWN FOR ARTICLE Full terms and conditions of use: http://www.tandfonline.com/page/termsand-conditions This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents......

Words: 7331 - Pages: 30