• Journal of Construction Engineering and Project Management
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• v.7 no.1
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• pp.13-25
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• 2017

Construction projects have been observed to have problems of project delays and disruptions and the South African construction industry is not an exception. This research identified causes and effects of project delay and disruption through a desktop study. Subsequently, a questionnaire was designed and used to conduct a survey to obtain the views of the three main construction project participants - clients, consultants, and contractors. The questionnaire contains 48 causes and 13 effects of project delay and disruption identified from the desktop study. This research identified sixteen most important causes of project delay and disruption and five most important effects of delay and disruption. Sixteen most important causes were: (1) strikes, (2) rework due to errors during construction, (3) shortage of materials in market, (4) suspension of work by the client, (5) poor communication between the parties, (6) ineffective planning and scheduling of project, (7) delays in issuing working drawings, (8) mistakes and discrepancies in design documents, (9) shortage of labours and equipment, (10) delay in decision making process by the client, (11) unforeseen ground conditions, (12) unclear and inadequate details in drawing, (13) inadequate contractor's experience, (14) delay in approving changes in the scope of works, (15) delay in material delivery and (16) unacceptable quality of materials. The five major effects include: (1) create stress on contractors, (2) cost overrun, (3) time overrun, (4) poor quality of work due to rush, and (5) disputes. Furthermore, the result of this research was compared with the result of previous studies conducted in other regions of Africa in terms of causes and effects of project delay and disruption. The research concludes that numerous causes and effects of delay and disruption are limited to South African construction projects based on the comparison. The causes limited to South African construction projects include: (1) strikes, (2) suspension of work by the client (3) mistakes and discrepancies in design documents (4) delay in approving changes in the scope of works and (5) unacceptable quality of materials, while the two major effects limited to South African construction projects includes: (1) create stress on contractors and (2) poor quality of work. In conclusion, some recommendations were made in order to minimise the causes of delay and disruption identified.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.540-553
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• 2007

Strategic management of changes is very significant for all types of construction projects. Project management teams must have the ability to respond to changes effectively in order to minimize their adverse impact on the project. The study focuses on the causes, their frequent effects and effective controls for changes in educational building projects. To achieve the study objectives, a questionnaire survey was carried out to collect relevant information. Through the literature review, 53 causes, 16 effects and 30 potential controls for change orders were identified. These provided the basis for the formulation of the questionnaire. Responses from 92 professionals who were involved in the educational projects in Singapore were analyzed. They included 28 developers, 33 consultants and 31 contractors. From the survey findings, the most important causes of changes were identified. The study revealed the most frequent effects and most effective controls for each cause of change order. Arising therefrom, a comprehensive tabulation of the 53 causes and their frequent effects and effective controls was also developed. A timeline for implementing the controls was developed through in-depth interviews with the professionals. The study would assist building professionals in taking proactive measures for reducing change orders for educational buildings; furthermore, the timeline would also be helpful for them to implement controlling strategies at the appropriate time. Recommendations were suggested based on the research findings.

• Journal of Construction Engineering and Project Management
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• v.2 no.4
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• pp.25-31
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• 2012

The growing rate of delays is adversely affecting the timely delivery of construction projects. This study therefore assesses construction stakeholders' perception of the causes of delays and its effects on project delivery in a bid to proffer solution in minimizing the occurrences of delays. Questionnaire was used to elicit responses from construction stakeholders; a total of thirty three causes of delays, seventeen resultant effects of delays and fifteen methods of minimizing construction delays were identified for the study based on literature reviews. The results suggest that client's cash flow related problems are the main causes of delays while time and cost overruns are the major identifiable effects of delays in construction projects. However, adequate project planning and budgeting were suggested as possible ways of minimizing the occurrences of delays.

• Journal of Applied Reliability
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• v.11 no.4
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• pp.387-398
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• 2011

$217Plus^{TM}$, a newly developed as a surrogate of the MIL-HDBK-217, may be widely applied for reliability predictions of electronic systems. In this study, we performed sensitivity study of the $217Plus^{TM}$ system model to various parameters. Specific attention was put to logistics model and its behavior has been examined in terms of non-component failure causes. We first briefly explained the $217Plus^{TM}$ methodology with system level failure rate evaluation. We then applied experimental designs with several failure causes as factors. We used an orthogonal array with three levels of each parameter. Our results indicate that cannot duplicate, induced, and wear-out causes have dominant effects on the system failures and design, parts, and system management have much less but a little strong effects. The results in this study not only figure out the behavior of the predicted failure rate as functions of failure causes but provide meaningful guidelines for practical applications.

• The Korean Journal of Health Service Management
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• v.5 no.3
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• pp.123-132
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• 2011

To evaluate the impact of avoidable mortality on the changes in life expectancy at birth in Korea. Standard life table techniques and the Arriaga method were used to calculate and to decompose life expectancy changes by age, effects and groups of causes of avoidable mortality among two periods(1990-2000 and 2000-2009). A list of causes of avoidable mortality reached by consensus and previously published in Spain was used. Mortality in young adults produced a reduction in life expectancy at birth during the 1990-2000, but there was an important increase in life expectancy at birth during the 2000-2009; in both cases, this was the result of factors amenable to health policy interventions. The highest improvement in life expectancy at birth was due to non-avoidable causes, but avoidable mortality through health service interventions showed improvements in life expectancy at birth in those elderly people than 1 year and in those younger. Making a distinction between several groups of causes of avoidable mortality and using decomposition by causes, ages and effects allowed us to better explain the impact of avoidable mortality on the life expectancy at birth of the whole population and gave a new dimension to this indicator that could be very useful in public health.

• English Language & Literature Teaching
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• v.13 no.1
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• pp.87-110
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• 2007

Past studies conducted on the students' verbal participation both in and out of class have explored and identified variables affecting the process of learning to speak English. However, little is known about the causes and effects of these variables. A survey form developed from a previous study was administered to 468 university students taking English conversation classes from native speakers of English. To better understand the causes and effects of speaking barriers, path analysis was administered as the main tool of investigation. The results of the study indicate that familiarities toward NS (Native Speaker) teachers, learner faithfulness, che-myon, NS teachers' classroom management skills, and NS teacher's trustworthiness account for 50.72% of speaking grades. These factors are causally related to learner attitudes. However, with regard to speaking grades, all of the above factors except che-myon are also causally related with each other. Therefore, it was concluded that learner attitudes can be improved by minimizing che-myon, however, che-myon itself cannot be a predictor of speaking grades. To validate the findings of the study, related research work is discussed and implications are provided.

• Proceedings of the Korean Reliability Society Conference
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• 2011.06a
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• pp.257-264
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• 2011

In this study, we performed sensitivity study of the $217Plus^{TM}$ system model to various parameters. Specific attention was put to logistics model and its behavior has been examined in terms of non-component failure causes. We first briefly explained the $217Plus^{TM}$ methodology with system level failure rate evaluation. We then applied experimental designs with several failure causes as factors. We used an orthogonal array with three levels of each parameter. Our results indicate that cannot duplicate, induced, and wear-out causes have dominant effects on the system failures and design, parts, and system management have much less but a little strong effects. The results in this study not only figure out the behavior of the predicted failure rate as functions of failure causes but provide meaningful guidelines for practical applications.

• Korea journal of population studies
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• v.6 no.1
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• pp.43-69
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• 1983

This study was conducted to make the life tables from specific causes of death in Korea. Both "Life tables of Korea in l978-79" and "the statistics on causes of death statistics in 1980" issued by Economic Planning Board were used as source of data for this study. Among the 58, 187 death certificates reported to the concerned authorities, 39, 801 causes were drawn for the purpose of this study. As a result, it is revealed that two thirds of men in Korea died from these 10 major causes of death. The summarized results are as follows: 1. According to recent statistics, 10 major causes of death in 1980 were shown in the order of 1) malignant neoplasms, 2) cerebrovascular disease, 3) accidents and adverse effects, 4)hypertensive disease, 5) ischaemic heart disease and heart attack, 6) chronic liver disease and cirrhosis, 7) tuberculosis, 8) pneumonia, bronchitis, emphysema and asthma, 9) suicide, 10) diabetes mellitis. 2. The major causes of death in Korea were very similar to those of developed countries such as West Germany, Denmark and Japan. This means that our pattern of death causes is almost approaching to that of developed countries. 3. Our crude death rate in 1980 was on the line of 6.6 per 1, 000 people. This is very low level, compared with 12.1 in West Germany and 10.0 in Denmark, however, our age sepcific death rate was on the verge of doubled level in each age category as to that of West Germany, Denmark and Japan. The fact tells us that our death rate is very high yet, especially in young and prime adult age, and the proportion of the aged is quite low. 4. Average ages of people died from malignant neoplasms, cerebro vascular diseases and hypertensive diseases were 63.1, 66.6, 67.3 respectively, however, that of accidents and adverse effect was only 42.5. This shows that accidents occur indifferently from age. 5. In the curve of eventual death probability, the curve of malignant neoplasms was the highest of all curves before 60 in age. However, the probability curve of eventually dying from accidents and adverse effects tends to decline with age. 6. In this study five life tables from major causes of death (four leading causes of death and of tuberculosis) were constructed for 1979. These life tables are reflecting accurately the effects of age distribution on the specific cause of death. In the surviving curje of these tables we can see that the curve of accidents is adversely related to age. While curves of neoplasms, hypertension and tuberculosis are not diminishing before 40 in age, they are going sharply downward after 50 in age.ard after 50 in age.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.69-72
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• 2005

For reinforced concrete column under sustained loads, the member suffers additional lateral deflection due to creep. This deflection leads to additional bending in the member, which in turn causes the column to deflect still further. Therefore the secondary moment due to additional deflection causes an increase in primary moment and the strength of column is reduced. And also creep buckling may occur. On this study, nonlinear analysis of reinforced concrete long column including crack effects is carried out and then the strength of long column is revaluated.

• Journal of Preventive Medicine and Public Health
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• v.38 no.2
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• pp.197-202
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• 2005

Objectives: During the spring of 2002, an unprecedented 2 Asian dust events were experienced in Seoul. On those days, the $PM_{10}$ was surprisingly increased, with daily $PM_{10}$ averages exceeding $600\;and\;700{\mu}g/m^3$ on March 21 and April 8, respectively. Accordingly, public concern relating to the possible adverse health effects of these dust events has increased, as the dust arrives in Korea after having flown over heavily industrialized eastern China. We investigated the effects of these Asian dust events on the mortality during the spring of 2002, in Seoul, Korea. Methods: The total number of deaths per day during the spring of 2002 in Seoul was extracted form the mortality records of the National Statistical Office. We constructed 14 Asian dust days (March 17-March 23, April 7-April 13) and 42 control days during the 56 day study period (March 3-April 27) with respect to the days of the week. The daily average numbers of deaths between the Asian dust and control days were analyzed, with adjustment for meteorological variables and pollutants. Results: The daily PM10 average during the Asian dust weeks was $295.2{\mu}g/m^3$, which was significantly higher than during the control days (p<0.001). The daily average number of deaths from all causes during the Asian dust days was 109.9; 65.6 for those aged 65 years and older, 6.7 from respiratory causes (J00-J99) and 25.6 from cardiovascular causes (I00-I99). The estimated percentage increases in the rate of deaths were 2.5% (95% CI=-5.0-10.6) from all causes; 2.2% (95% CI=-7.4-12.8) for those aged 65 years and older, and 36.5% (95% CI=0.7-85.0) from respiratory causes, but with a 6.1% (95% CI=-19.7-9.7) decrease in deaths from cardiovascular causes. Conclusion: The Asian dust events were found to be weakly associated with the risk of death from all causes. However, the association between dust events and deaths from respiratory causes was stronger. This suggests that persons with advanced respiratory diseases may be susceptible to Asian dust events.