Vascular Sonography English Class


Vascular Sonography

Student name


Vascular Sonography


Sonography is defined as a diagnostic medical procedure, which uses high frequency sound waves to produce dynamic visual images of organs, blood flow, and tissues. At this point, Sonography is increasingly being used in the detection and treatment of heart attack, heart diseases, and vascular diseases that can lead to stroke. Vascular sonography is, therefore defined as the process of using high-pitched sound waves to study the blood vessels in the body. As a matter of fact, an ultrasound image provides an essential way of evaluating the circulatory system of the body. The images are captured in real-time thus helping radiologists to monitor the blood flow to organs/tissues all over the body. In addition, the ultrasound sound images help radiologists to locate and identify blockages and abnormalities like blood clot, emboli, and plaque thereby facilitating a plan for effective treatment.


Vascular refers to the blood vessels that carry blood from the heart to the other body organs and vice versa. Vascular diseases are unhealthy changes that occur in blood vessels. The circulatory system is very complex in function and structure. The flow of blood is influenced by a number of factors among them are elasticity of the vessel walls, vascular injuries, and the tone of vascular smooth muscle. Individuals with vascular injuries as a result of penetrating or blunt trauma can be divided into those which have direct clinical signs of arterial/venous injury and those with indirect signs. Trauma without direct signs represents a particular challenge as a result of the undetected vascular injury. In the past century, there was a conflict regarding the management of vascular trauma because many people advocated for aggressive surgical exploration. The approach led to a high rate of unnecessary surgery thus generating the need for selective diagnostic imaging to establish if operative intervention is required.

The potential for using the reflection of sonography in the visualization of the internal organs of the human body started in the late 1930s. Austrian neurologist Dussik K.T developed a sonographic transmission technique in order to visualize cerebral ventricles. When a particle is activated to vibrate in its equilibrium position, the vibration is transmitted to a neighboring molecule in the medium.

In this manner, kinetic energy is propagated from one molecule to the other thereby spreading through the medium in what is similar to sine wave pattern. The sound waves compresses and expands the medium as it travels through. An ultrasound image is created thus revealing any abnormality in the blood.

Sonography guided vascular access

Vascular access is an essential procedure that clinicians have to master. Injuries, obesity, intravenous drug use, and chronic medical conditions can make placements of vascular catheters in both peripheral and central veins time-consuming and challenging. In the recent years, there have been dramatic improvements in portable sonar technology, which includes the development of relatively inexpensive machines with adequate resolution to guide needle placement through tissues.

Transducer selection

Transducer characteristics such as shape and frequency determine sonar image quality. For the purpose of vascular access, it is essential to use high frequency as well as small footprint transducers. As a matter of fact, the high-frequency linear array transducer offers a higher resolution of the superficial areas of soft tissues that includes veins and arteries.


The color Doppler and B-mode are the main ultrasound modes that can used to access venous tissues. The B-mode produces recognizable 2D gray scale images. Color Doppler can applied to characterize blood flow. The mode detects optimal flow of blood when the transducer is parallel to the flow. However, when the transducer is perpendicular to the vessel, the detection of flow is worst.

Optimizing image quality

Best visualization of target vessels calls for an optimal machine setting. Generally, proper transducer selection and the selection of pre-programmed vascular sonography settings offer acceptable quality of images. Moreover, other controls that can further enhance the quality of the image are focus, depth, gain, and frequency.

Proper depth adjustment offers a better target vessel imaging. Furthermore, it facilitates the tracking of equipment used through the tissue. When the depth setting is increased, the target vessel becomes smaller. Contrary, when the depth is too shallow, significant structures that surround the target vessels may be lost. That is to say, it is necessary to select the appropriate depth for the target vessel.

The brightness of an image on the screen is directly controlled by the gain setting of the sonar machine. Furthermore, it depends on the selected gains. By increasing the gain of the machine, the image is made brighter thereby easy to study. However, when the gain is decreased, the image becomes darker thus very difficult to analyze. Actually, the highest resolution of any image displayed is at the focal zone. With the use of sonar machines, it is essential to put the focus at the level of the target vessel of interest.

Physical Principles of Sonography: Doppler Effect

During the examination of blood vessels, the moving blood cells act as the reflectors. To specific, the red blood cells act as the reflectors as a result of their great majority in the blood cells. The difference between the frequency of the reflected and transmitted sound is known as Doppler-frequency-shift. If the direction of the blood flows to the transducer, then Doppler-shift is positive. Nevertheless, if the direction of blood flow is away from the probe, the Doppler-shift is negative.

The Doppler-shift can be displayed in a number of ways, which depend on the Doppler technique. The use of spectral mode is popular because Doppler tracing can be seen. Moreover, color/Doppler mode can be used. This mode displays the Doppler-shift as shades of one or more color inside the color box.

Spectral Doppler Sonography

Spectral Doppler techniques display consists of two types: pulsed and continuous wave Doppler modes. Pulsed wave Doppler mode is used in peripheral/abdominal vascular studies while continuous wave Doppler is to measure high velocities. A pulsed wave transducer contains one piezoelectric crystal.

In connection the above point, the crystal transmits pulses at regular intervals. The same crystal receives reflected signal and compares it with the transmitted reference. Pulsing the waves allow Doppler measurements to be taken from a specific region within the image field thereby allowing velocity measurements from the selected vessels. A pulsed wave allows precise localization of the volume of tissue from, which the Doppler blood flow signal is sampled in contrast with the continuous wave technique.

Duplex imaging uses pulsed wave Doppler with a two-dimensional real-time image. Normally, the location of the target volume is displayed on the B-scan tomogram. At this point, the sampling gate can be moved to the lumen of the vessel as highlighted on the real-time image. The velocity changes, which occur in each cardiac cycle, can be displayed graphically. The running time is placed on the horizontal axis. If the cursor is aligned parallel to the blood vessel, the velocity of the moving cells can be seen on the vertical axis.

During a duplex Doppler examination, the Doppler-shift can be displayed graphically or in audible form. The arteries have swish-like sounds while veins have continuous wind-blow-like sounds. The intensity of the audible sounds is directly proportional to the quantity of moving blood cells. The higher of the velocity of the flowing blood, the higher the audible sound is. In effect, pulsed wave Doppler sonography promotes the assessment of the direction, presence, and velocity of blood flow in the sample volume.

The most commonly used methods for measuring the blood flow velocity in a vessel are the maximum velocity method and uniform insonation method. In the uniform insonation method, the entire lumen of the vessel is incorporated into the gate. Nevertheless, maximum velocity method is where a small sample volume is placed in the placed in the centre of the vessel.

Color Doppler imaging

The basics of color Doppler imaging are almost similar to pulsed wave Doppler mode; however, it has a number of multiple sample volumes inside a circumscribed region known as a color box rather a visible one. The position and size of the color box on the B-mode image is determined by the operator. This type of sonography displays the two-dimensional flow information in color superimposed on the B-mode image of the vessel as well as the surrounding tissue.

Inside the color box, all the points are in a shade of red or blue rather than a shade of gray. The direction of flow relative to the transducer is illustrated on a color bar adjacent to the image. By convection, the flow the move towards the transducer is red whereas the flow away from the transducer is blue.

Color Doppler sonogram technique offers movement-information regarding a large part of the image. In point of fact, color Doppler flow imaging promotes the assessment of the presence, quality, and direction of blood flow more quickly than it does in other noninvasive technique.

Planes and Views

For the purposes of vascular access, two types of planes are used: longitudinal and transverse views. In the transverse view, the transducer plane is placed in cross section of the target vessel and the vessel is displayed on the screen as a circle. However, in a longitudinal view, the transducer plane is placed parallel to the one another and the vessel is displayed on the screen as a long tube running across the screen. On the whole, a longitudinal view allows visualization of the entire vessel of interest but requires that needle, transducer beam, and the target vessel to be held parallel to one another.

Differentiating vein and artery

Differentiating between vein and artery is important to safely perform sonography guided vascular access. The simplest way to differentiate between artery and vein is the compressibility of veins. Basically, veins compress with minimal pressure while arteries retain much of their original shape and appearance despite a heavy pressure. While performing an internal jugular vein placement, it is necessary to visualize the influence of respiratory variation on the vein diameter. Trendelenberg positioning and valsalva maneuvers make vein larger; however, it has a minimal impact on the carotid artery.

Scanning techniques

The guidance of vascular access using sonogram can be grouped as dynamic or static. In the static use of sonogram, providers apply sonogram to localize the vein and mark the site of the needle insertion on the skin. The dynamic guidance entails the use of sonogram in real-time with continuous visualization of the needle insertion throughput the procedure. The success rate for dynamic guidance is higher than those of static technique.

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The Rise and Grandeur of Qing Dynasty Paper

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The Rise and Grandeur of Qing Dynasty

Summary of the development

The Qing dynasty was the last Chinese dynasty with began in 1644 and ended in 1912. It began after the decline of Ming dynasty which had ruled for 276 years. Qing dynasty was being ruled by a bordering nomadic clan known as Manchus. The Manchus forcefully entered Beijing to seize the throne from the Ming rulers. After crossing the walls of Beijing, the Manchu forces engaged in a fight against the Li Zicheng’s army. They succeeded and eventually managed to take the throne and that marked the beginning of the Qing Dynasty. The establishment of the Qing Dynasty marked the beginning of a period of growth for the Chinese and Manchu people. The public works sector significantly added to the growth of the cities and the living standards of people improved due to increased trade and lower taxes on people. Western missioners, who came to China at the time, brought about Christianity and also influenced the Chinese in science. Politically, positions were shared among the Manchu and Chinese people. They had well organized military units which especially played an important role in the success of the dynasty.

Historical context of the rise and grandeur of the Qing dynasty

The establishment of the Qing dynasty was preceded by a period in which the Ming government was weak due to their inability to address famine, natural disasters and economic instability in the empire. People were then convinced that the Ming had lost the Mandate of Heaven. Rebellions then erupted from the Mongols and Jurchens. It is the invasions of the Mongolians and attacks from the Manchus that led to the eventual fall and rise Ming and Qing dynasties respectively. Just before the Ming dynasty was overthrown and Qing dynasty established, China’s economy was undergoing one of the greatest expansions in history. New markets were being established and merchants were expanding their trade activities as far as the South China Sea. Through the ‘Ming Voyages’, Chinese merchants were able to reach Southeast Asia and were actively involved in businesses. The economic growth (dynamic, commercialized) continued through the Qing dynasty period until the eruption of the Opium wars. In 1900, a group of rebels in southern China carried out rebellion against the Qing Dynasty. The success of the revolt saw the establishment Republic of China and the end of Chinese dynastic system.  

Significant contingent factor(s) relating to the rise and grandeur of Qing dynasty

The most significant contingent factors relating to the rise and grandeur of the Qing dynasty include the decline of the Ming dynasty, favorable policies and also the strong economic foundation that preceded the Qing dynasty period. The prominent problems as economic instability, natural disasters weakened the Ming dynasty and that acted as an important factor in influencing the Mongolians and Manchu’s to rebel and finally overthrow the government. That gave rise to the Qing Empire. Favorable policies allowed for lower taxes and improved living standards of the people who in turn gained confidence on the leadership of the Qing dynasty.  Such policies allowed for active providence of public goods to improve the economic well-beings of the people of China and Manchu. The economic foundation laid in the pre-Qing dynasty period allowed for more growth and stability in the empire and largely contributed to its continuity through to the 20th century.

Historical Complexity

The Manchus (rulers of the Qing Dynasty) received much resistance because they were non Han Chinese. They had to adopt Chinese cultures and Ming institutions to be able to dominate over the empire and to reduce resistance. They, for example, sustained the Confucian temple rituals, court practices and civil service. To quell the ever inherent internal rebellion and foreign invasions, Qing rulers subdued China Proper and went beyond the borders to conquer Outer Mongolia, Central Asia (Tibet) and Taiwan, among other neighbouring states. In this way, they were able to eliminate threats both from within and from outside China Proper. Qing rulers were always suspicious of the Han Chinese. As a result, they implemented measures to ensure that the relatively fewer Manchus rulers were not absorbed into the Han Chinese population that was dominant. Such measures included outlawing intermarriage between the two groups and forbidding Chinese migration into the Manchu mainland, among others.

Significance of the rise and grandeur of Qing dynasty in the world today

The significance of the Qing dynasty is evident in the world today. First, it was a period that to a large extent lay foundation for the Republic of China particularly in terms of social and cultural ideals. Economically, the period influenced trade across the world and shaped trade trends that are still in effect even in the world today such as those established between China and Europe. It was the time in which religious constructs took shape in terms of the introduction of the world religions that exist in the world today. Missioners brought Christianity into China, a fact that has continued to influence people within and without the country. The Qing dynasty period is also well known as the period for the development of art in form of paintings and sculpturing. Much of the styles and principles of the arts at the time have had great influences on the art pieces in the contemporary world. Many artists today have borrowed specific techniques and styles from the paintings of the Qing dynasty period. Also, the period also gave rise to the Chinese culturalism and self-sufficiency which still forms an important ideal for the Chinese government today.

Works Cited

‘China’s Last Empire: The Great Qing’. Choice Reviews Online 47.07 (2010): 47-3974-47-3974. Web.

Hall, Eleanor J. Ancient Chinese Dynasties. San Diego, CA: Lucent Books, 2000. Print.

Udry, Stephen P. ‘China’s Last Empire: The Great Qing – By William T. Rowe’. Historian 73.3 (2011): 603-604. Web.

Wang, Wensheng. ‘China’S Last Empire: The Great Qing , By William T. Rowe . Cambridge MA: Harvard University Press, 2012 (Paperback Edition). [Viii] + 360 Pp. US$18.95 (Paperback).’. The China Journal 71 (2014): 285-288. Web.

Zhang, Wei-Bin. The Rise And Fall Of China’s Last Dynasty. New York: Nova Science Publishers, 2011. Print.






History 121-004

March 19, 2015


The period between 1790 and 1850 brought with it the age of industrial revolution in Europe and the Unites States (US). Though the industrial revolution began very clandestinely in England it managed to penetrate into the US. The age of the industrial revolution involved the discovery and invention of machines such as the Cotton Gin, The Spinning Wheel and The Steam Engine amongst others. Such technological and industrial change also brought a lot of changes and influences in the political, transport, communication, social and economical spheres. It brought along a new way of life, the growth of a nationalized economy and a market revolution across the developed world (Boyer, et al. 2011).

The Cotton Gin Description

Eli Whitney an American inventor is credited with the invention of the Cotton Gin in the early 1790s. The Cotton Gin was a machine that helped to quickly, faster and easily remove cotton from its gin or seed. The mechanical invention was made up of revolving block like cylinders which had spiked teeth to remove the cotton.  The spiked teeth removed the cotton from the seed and hence increased productivity. This brought significant changes in the American textile industry as well as the nation as a whole. Previously, separating the cotton from the seed involved the utilization of many human resources in a manual and time consuming manner. Though, the Cotton Gin was discovered in the year 1793 it was patented in the year 1794 after many imitations had already been developed.  With the invention of the machine the demand for cotton increased, the demand for slaves to pick the cotton increased, textile production increased, cotton farming as a cash crop increased and the South American economy soared (Boyer, et al. 2011).

The Steam Engine Description

A Scottish discoverer by the name of James Watt is credited with the perfection of the steam engine in the late 1760s. He worked along with the pioneer of the steam engine by the name of John Roebuck. His major invention was the creation of a spare condensing chamber that highly prevented powering steam loss. Basically, his mechanically transforming invention was a steam powered invention that utilized heat to produce the steam and a condenser chamber to curtail the loss of the much needed steam energy. The steam engine consequently brought in a lot of different machineries for different uses in diverse areas. These included steam powered tractors, steam powered locomotives, steam powered boats and steam powered looms amongst others. They brought a revolution in the transport, communication, manufacturing and economic systems in the US (Boyer, et al. 2011).

The Economic Ramifications of the Two Inventions

The two inventions among other brought about the changes in the economy of the US and other areas such as demographics, slavery, mass production, transportation systems and the relations between the South and the North of the time. The invention of the Cotton Gin led to increased productivity in the separation of the cotton from the seeds. Subsequently, this led to the faster and efficient production of the much needed processed cotton for the textile promising industry.  The ripple effects caused by these changes in the South meant that more slaves who were of black origin and other races were needed in the South in regions such as Texas, Alabama, Carolina and Mississippi and Tennessee. This is because most of them were based there as well as much of the farming lands and others were easily smuggled in (Boyer, et al. 2011).

Thus, it led to increased immigrants acceptance in such of man power for the Cotton Gin machines, the increased cotton farms and the increased production of textile in the industrialized Northern regions such as Indiana, New York, Wisconsin and Massachusetts. With time cotton was regarded as king as its production had increased from a mere 1,500 pounds in the late 1790s to more than 35,000 pounds by the early 1800s. While the South was based on savage ideology and a plantation economy the North was more of an urban culture that led to cities and interrelation amongst different cultures. The difference in economic well being, relations, leadership policies, slavery and anti-slavery movement ultimately led to the American Civil War of 1861 – 1865. This is because the South expanded significantly while it utilized cheap slave labor while the North was changing dynamically as influenced by changing political, literacy, social and global issues (Boyer, et al. 2011).

On the other hand, the invention of the steam engine impacted many spheres including manufacturing, transport, communication, banking and urbanization. The transport systems were improved with the construction of roads such as the Cumberland Road, the construction of railroads such as Baltimore and Ohio Line and the development of canals such as the Erie Canal. These transport lines helped to move agricultural produce, finished goods, mail, animals, printed material and human beings across the South and the North. This in turn led to the rise of manufacturing hubs, agricultural areas, cities, educational blocks and population diffusion. Ultimately, this lead to market revolutions which influenced how Americans shopped, the rise of capitalism, the rise of banks, city zoning and the change from farming to labor employment. However, it also brought in the negatives associates with rapid urbanization and economic growth such as poor sanitation, poor wages, unemployment, settlements, starvation and high mortality rates (Murrin, et al. 2015).

Political Ramifications of the Two Inventions and Conclusion

In the years between 1790 and the 1850 the American economy, society, demographics, regions and the ideology changed rapidly. The north was more accommodative and adoptive while the South was more rigid and repressive. The economy of the South and its hunger for slaves grew such that it threatened the existence and the continued sustenance of the North. The federal north needed to reign on the fast developing economy in order bring in control over the stately South. The drafting of the proposed American constitution in 1787 put the two regions political asunder (Murrin, et al. 2015).

The North was wary that the South would force its hunger for slaves into the North which it regarded as a strange source of power. This was to become true when such theories entered the Congress discourse. However, the Federal authorities tried to avert any crises by accepting compromises such as the 1820s Missouri Compromise. That was not to be as the political rifts between the two regions became bigger due to political selfishness. The Northern non- slave whites who however did not vouch for equality among the races refused to have a common political and economical ground with the slave holding southerners. They were afraid of the Westward expansion and the use of slavery which they saw as a threat to their new conquests (Murrin, et al. 2015).

The rift was transcended by the fact that the senate and congress had almost equal representatives from the two ideological divides. Later compromises such as the Fugitive Slave Act and the Kansa-Nebraska Act only helped to elevate the political differences (Abzug and Maizlish 2015). Ultimately, the differences would spill into several states and the battle of the damned between the abolitionists and the pro-Slavery supporters would emerge. From the bleeding Kansas the battle poured into the American civil war. The political heats and differences had to be refreshed with the fountains of blood (Boyer, et al. 2011).


Abzug, Robert H., and Stephen E. Maizlish, . New Perspectives on Race and Slavery in America. Kentucky: University Press of Kentucky, 2015.

Boyer, Paul, Clifford Clark, Karen Halttunen, Joseph Kett, and Neal Salisbury. The Enduring Vision: A History of the American People. 7. Boston: Cengage Learning, 2011.

Murrin, John, Paul Johnson, James McPherson, Alice Fahs, and Gary Gerstle. Liberty, Equality, Power: A History of the American People. 5. Boston: Cengage Learning, 2015.


Regression Correlation Math


Based on the given data, the scatter plot of CCI vs Median Household Income is plotted.

From the scatter plot, it can be seen that the data points appear to be scattered around a straight line with positive slope, such that there appears to be a line trend between the Median Household Income and CCI. Therefore it is likely that there is a positive linear relationship between the Median Household Income and CCI.


A correlation analysis is carried out between the variables Median Household Income and CCI, and the result is shown below:

Correlation: CCI, Median Household Income ($1000)


Pearson correlation of CCI and Median Household Income ($1000) = 0.829

P-Value = 0.006

From the result, it can be seen that the correlation coefficient is 0.829. This implies that there is a strong positive linear relationship between Median Household Income and CCI.

The coefficient of determination r2 can be calculated by taking the square of the correlation coefficient.

r2 = 0.829^2 = 0.6872

The coefficient of determination r2 being 0.6872 implies that 68.72% of variation in CCI can be explained using the Median Household Income

Also 1 – r2 = 1 – 0.6872 = 0.3128

This implies that 31.28% of variation in CCI cannot be explained using the Median Household Income.


A regression analysis is carried out between the variables CCI and Median Household Income such that a linear model in predicting CCI is to be fitted using Median Household Income as the independent variable. The result is shown below:

Regression Analysis: CCI versus Median Household Income ($1000)


Analysis of Variance

Source                             DF  Adj SS  Adj MS  F-Value  P-Value

Regression                          1    2829  2829.0    15.43    0.006

Median Household Income ($1000)   1    2829  2829.0    15.43    0.006

Error                               7    1283   183.3

Total                               8    4112

Model Summary

S    R-sq  R-sq(adj)  R-sq(pred)

13.5389  68.80%     64.34%      50.08%


Term                              Coef  SE Coef  T-Value  P-Value   VIF

Constant                          -599      176    -3.41    0.011

Median Household Income ($1000)  19.22     4.89     3.93    0.006  1.00

Regression Equation

CCI = -599 + 19.22 Median Household Income ($1000)

From the normal probability plot of the CCI, it can be seen that the data points all lying close to a straight line. This implies that the residual is approximately normally distributed. Also from the residual vs fitted value plot, it can be seen that the data points appeared to be randomly scattered about the zero value horizontal line. This implies that the residual has no relationship with the fitted value. Therefore the linear regression model is adequate.

Based on the result of regression analysis, the fitted model is found to be:

CCI = -599 + 19.22 Median Household Income ($1,000)

The slope coefficient of 19.22 implies that when the Median household Income increases by $1,000, the CCI is expected to increase by 19.22.


From the result of the regression analysis, the standard error of the estimate is found to be 13.5389. This implies that standard deviation of the residual in the regression is 13.5389. The descriptive statistics of CCI alone is shown below:

Descriptive Statistics: CCI


Variable  N  N*   Mean  SE Mean  StDev  Minimum     Q1  Median      Q3  Maximum

CCI       9   0  91.66     7.56  22.67    61.60  67.20   91.50  110.70   125.40

The standard deviation of CCI alone is 22.67. Therefore with the Median Household Income, the standard deviation decreased from 22.67 to 13.5389.


In order to determine whether there is significant linear relationship between the CCI and the Median Household Income, a hypothesis test is carried out on the slope term of the regression.

Null hypothesis: The slope term of the regression is zero.

Alternative hypothesis: The slope term of the regression is not zero.

Take the level of significance for the test be 0.05.

From the result of the regression, the test statistic for the slope term is 3.93.

The degree of freedom is 9 – 2 = 7, the corresponding p-value is 0.006

Since the p-value of 0.006 is smaller than the level of significance of 0.05. The null hypothesis is rejected. Therefore it can be concluded that the slope term of the regression is not zero, and thus there is significant linear relationship between CCI and Median Household Income.


Based on the given data, a multiple linear regression model is built in predicting the average price of gold from the price of copper, silver and aluminum. The result is shown below:

Regression Analysis: Gold ($ per  versus Copper (cent, Silver ($ pe, Aluminum (ce


Analysis of Variance

Source                      DF  Adj SS   Adj MS  F-Value  P-Value

Regression                   3  104445  34815.0    12.19    0.002

Copper (cents per lb.)     1      18     18.1     0.01    0.939

Silver ($ per oz.)         1   69634  69633.6    24.38    0.001

Aluminum (cents per lb.)   1   26208  26208.3     9.18    0.016

Error                        8   22845   2855.7

Total                       11  127291

Model Summary

S    R-sq  R-sq(adj)  R-sq(pred)

53.4386  82.05%     75.32%      66.28%


Term                       Coef  SE Coef  T-Value  P-Value   VIF

Constant                  -51.6     87.8    -0.59    0.573

Copper (cents per lb.)    0.070    0.875     0.08    0.939  1.44

Silver ($ per oz.)        18.78     3.80     4.94    0.001  1.08

Aluminum (cents per lb.)   3.54     1.17     3.03    0.016  1.41

Regression Equation

Gold ($ per oz.) = -51.6 + 0.070 Copper (cents per lb.) + 18.78 Silver ($ per oz.)

+ 3.54 Aluminum (cents per lb.)

Fits and Diagnostics for Unusual Observations

Gold ($                  Std

Obs  per oz.)    Fit  Resid  Resid

10     448.0  341.4  106.6   2.11  R

R  Large residual

First of all, from the normal probability plot, it can be seen that all the data points of the residuals lie around a straight line. This implies that the residuals can be approximated by normal distribution. This is also verified by the histogram of the residual which demonstrates a shape close to normal distribution. From the plot of residual vs fitted value, it can be seen that the data points appeared to be randomly scattered about the zero value horizontal line. This implies that the residual has no relationship with the fitted value. Therefore the linear regression model is adequate.

The coefficient of determination R2 is found to be 82.05%. This implies that 82.05% of variation in price of gold can be explained by the model. As a result, the R can be calculated by R = √82.05% = 0.9058. From the coefficients in the regression equation, it can be seen that the coefficients are all positive, and thus it is reasonable to believe that R is also positive in value, and the multiple correlation implies a strong positive correlation between the independent variables and the price of gold. Also 1- R2 = 1 – 82.05% = 17.95%. This implies that 17.95% of variation in gold price cannot be explained by the model. The adjusted R2, which take into account the effect of multiple independent variables, is found to be 75.32%. This implies that after taking into account multiple independent variables effect, the variation explained by the model is 75.32%.

The regression equation is found to be:

Price of gold ($ per oz.) = -51.6 + 0.070 Copper (cents per lb.) + 18.78 Silver ($ per oz.) + 3.54 Aluminum (cents per lb.)

The coefficient of Copper implies that given the price of Silver and Aluminum remain unchanged, when the price of Copper increase by 1 cent per lb. The price of gold is expected to increase by $0.07 per oz. The coefficient of Silver implies that given the price of Copper and Aluminum remain unchanged, when the price of Silver increase by $1 per oz, the price of gold is expected to increase by $18.78 per oz. The coefficient of Aluminum implies that given the price of Copper and Silver remain unchanged, when the price of Aluminum increase by 1 cent per lb., the price of gold is expected to increase by $3.54 per oz.

The standard error of estimate in the regression is found to be 53.4386. This implies that the standard deviation of the residual in the regression is 53.4386. The descriptive statistics for gold price alone is shown below:

Descriptive Statistics: Gold ($ per oz.)


Variable           N  N*   Mean  SE Mean  StDev  Minimum     Q1  Median     Q3  Maximum

Gold ($ per oz.)  12   0  388.1     31.1  107.6    161.1  328.8   379.3  445.5    613.0

The standard deviation of gold price alone is 107.6. Therefore with the regression model, the residual is decreased by more than half.

To check for the overall significance of the model, the hypothesis test on the slope terms is carried out.

Null hypothesis: All the regression coefficients are zero.

Alternative hypothesis: At least one of the regression coefficient is not zero.

The level of significance for the test is set to be 0.05.

From the output of the regression, the test statistic is 12.19.

The degree of freedom of numerator is 3. The degree of freedom of denominator is 8. The p-value is 0.002.

Since the p-value of 0.002 is smaller than the level of significance of 0.05, the null hypothesis is rejected. Therefore it can be conclude that at least one of the regression coefficients is non-zero, and thus the overall model is significant.

For each of the regression coefficient:

For Copper, the t value is 0.08, and the p-value is 0.939. Since the p-value is not smaller than 0.05, the variable Copper is not significant.

For Silver, the t value is 4.94, and the p-value is 0.001. Since the p-value is smaller than 0.05, the variable Silver is significant.

For Aluminum, the t value is 3.03, and the p-value is 0.016. Since the p-value is smaller than 0.05, the variable Aluminum is significant.

First Submission


First Submission



DATE:           02/05/2015

SUBJECT:    Memo on Ken Cureton, Systems Architecting and the Political Process.

On 5th February 2015, Mr. Cureton presented a lecture entitled, “Systems Architecting and the Political Process” to students at Loyola Marymount University, Los Angeles. Mr. Cureton was the Technical Council Chairman until 1 April 2011 in the NCO Industry Consortium (NCOIC). Since 2004, Mr. Cureton has been able to serve in various ranks. He has served as chairman of the Engineering Processes Functional Team and has continued to serve as Technical Council Chair Emeritus. He has been actively involved in NCOIC “voice of industry” in the design efforts to support the NGA, (National Geospatial-Intelligence Agency). He is also involved with Cloud Computing disseminating tagged data for systems in the emergency management sector for the US Federal Aviation Administration (FAA) Next-Generation Air Traffic Management System, the Australia Defense Organization (ADO) Single Integrated Environment, the North Atlantic Treaty Organization (NATO) Federated Mission Networking, and other national and international systems.

Mr. Cureton began the presentation with a brief history of the space shuttle dating back 1970s. Space shuttle was not funded until 1980s. The original space shuttle was manned. The designers tried several designs to come up with the final one. The solids were to be shipped by rail to Florida. As a result, the space shuttle had to be smaller than originally envisioned to fit into standard railway cars. Constellation program was replaced by the US national space policy that came up with final shuttle flight on July 8, 2011. The designers had to rely on Russians and others designers after that. Russian spacecraft are now the only means used by astronauts traveling to the International Space Station (ISS). Baikonur (Kazakhstan) is sole launch site used for manned missions to ISS. On May2014, Russians announced no more support to ISS after 2020, and as a result NASA now works with US companies to develop space taxis with goal of restoring US transport to USS by 2017. China began its manned space flight on 15thOctober in 2003. Their space laboratory is slated in 2015 for 20 days with three crews on board and expected to arrive at space from 2018. India has their space flight plane scheduled after 2017.

NASA $ 30M commercial program carried out by Boeing, Sierra Nevada Corporation Space Systems & Space successfully tested and monitored NASA X-51A “Wave Rider” on May 27, 2010. European space agency ESA also launched the unmanned vehicle that could be expanded. Mr. Cureton stated for the success of the space shuttle design, politics should not to be brought in technology, proper budget estimates, regulatory constraints and schedule deadlines should be considered. Government funding should not be relied on; private financing for unmanned systems should be encouraged. US perform strongly when stimulated by fear of foreign domination. Public support should be increased to counter the perceived threat of Russians and Chinese after 2020.

All in all, I appreciated Mr. Cureton vast knowledge on space technology. I also appreciated the information that Mr. Cureton shared with us. The information allowed us to get updated about present and future space technology.