• Journal of Construction Engineering and Project Management
• /
• v.10 no.1
• /
• pp.16-32
• /
• 2020

Cost and time control of projects is important in preventing project failure. However, achieving effective cost and time control in practice is often challenging. The challenges of project cost and time control in practice are investigated by carrying out a questionnaire survey on the top 150 construction contractors in the UK followed by in-depth semi-structured interviews of practitioners from 15 construction companies in the country. Quantitative analysis reveals that design change is the most important factor inhibiting the ability of UK contractors from effectively controlling both the cost and time of construction projects. Four of the top five factors inhibiting effective cost control are also the top factors inhibiting effective time control albeit in a different order. These top factors-design changes, inaccurate evaluation of project time/duration, risk and uncertainty, non-performance of subcontractors and nominated suppliers were also found to be endogenous factors to the project. Additionally, qualitative analysis of the interviews reveals 16 key challenges to prevent for effective project cost and time control in practice. These are classified into four categorised based on where they stem from as follows; from the organisation (1. Lack of integration of cost and time during project control, 2. lack of management buy-in, 3. complicated project control systems and processes, 4. lack of a project control training regime); from the construction management/project management approach (5. Lapses in integration of interfaces, 6. project control not being implemented from the early stages of a project, 7. inefficient utilisation and control of labour, 8. limited time devoted to planning how a project will be controlled at the outset); from the client; (9. Excessive authorisation gates, 10. use of adversarial and non-collaborative forms of contracts, 11. communication problems within client set-up, 12. obstructive client representatives) and; from the project team (13. Lack of detailed/complete design, 14. lack of trust among the project partners, 15. limited time devoted to project control on site, 16. non-factual reporting). The study posits that knowledge of these project control inhibiting factors and challenges is the first step at ensuring they are avoided and enable the implementation of a more effective project cost and time control process in practice.

• The KIPS Transactions:PartD
• /
• v.15D no.1
• /
• pp.147-154
• /
• 2008

Along with the trend of internet use, various web application developments have been performed to provide information that was managed in the internal database on the web by making a web server page. However, in most cases, a direct program was made without a systematic developmental methodology or with the application of a huge developmental methodology that is inappropriate and decreased the efficiency of the development. A web application that fails to follow a systematic developmental methodology and uses a script language can decrease the productivity of the program development, maintenance, and reuse. In this thesis, the auto writing tool for a dynamic web server page was designed and established by using a database for web application development based on a fast and effective script. It suggests a regularized script model and makes a standardized script for the data bound control tag creator by analyzing a dynamic web server page pattern with the database in order to contribute to productivity by being used in the web application development and maintenance.

• The KIPS Transactions:PartD
• /
• v.9D no.3
• /
• pp.457-466
• /
• 2002

In this paper, we designed and implemented a web-based dictionary of computing which keeps the data up-to-date. This dictionary shows the English information based on the FOLDOC (Free On-Line Dictionary Of Computing) dictionary file at the beginning of searching, and then one or more users can translate the information into Korean. This function is the new one only this dictionary has. Also, we can easily find any words we want to took up, even if we don't know the spelling completely, because the dictionary has various searching interfaces (searching for the words starting with inputted characters, searching for the words including inputted characters in the description, etc.) using a SQL Server DBMS and SQL. The performance test for CPU load factor shows that the server can support at least 1780 users at the same time.

• Journal of the Korean Society of Industry Convergence
• /
• v.22 no.6
• /
• pp.665-671
• /
• 2019

The estimated on-site accident rate in Forestry is relatively high. According to statistics of the accident, in the recent 5 years, from 2014 to 2018, forestry accidents have resulted in 98% of injuries and 87% of fatalities. Especially, there are significant geographical constraints to access to the scene in case of an accident. Even though the capacity of first aid capacity is notably emphasized its importance to minimize the scale of damages, the relevant employees have been educated only basic first aid, which is not considered circumstances or geographic limitations, by Occupation Safety and Health Acts. Therefore, the purpose of this study is to derive a direction for a forest emergency service system to increase forestry workers' survival and prevent secondary injury through securing 'Golden Time.' This study conducts analyzing relevant laws and regulations in domestic and international settings as well as looking at several concerned accident cases. The outcome of analysis presents an issue regarding the implementation of onsite first aid in forestry and existing risk factors depending on the working process. Finally, we suggest two ways to improve the forest emergency service that are 1) an appropriate curriculum and kit for forest first aid; and 2) a system for emergency transfer through sharing information between National Fire Agency (NFA) and emergency medical service center, and emergency and rescue mission using helicopter from NFA and Korea Forest Service.

• Safety and Health at Work
• /
• v.15 no.2
• /
• pp.164-171
• /
• 2024

Background: Telework adoption in Taiwan has surged because of government guidelines during the COVID-19 pandemic. This study examined the disclosure practices of Taiwanese-listed companies, assessing their adherence to government telework guidelines and their correlation with corporate governance, focusing on occupational health measures. Methods: We conducted a guideline-adherent cohort analysis of the 2020 and 2021 sustainability reports of 295 Taiwanese-listed companies. We assessed their disclosure of corporate measures for teleworking in alignment with two government guidelines, specifically occupational health measures. Using the McNemar test and general estimating equation analysis, we compared the 2020 and 2021 responses and examined their associations with corporate governance rankings. Results: Telework adoption increased significantly from 2020 to 2021, with 68% of companies reporting new work modes. The mentioning of government guidelines also increased to 67% by 2021. Companies with higher governance rankings were more likely to adopt online occupational health measures, including occupational health services (RR = 2.03; 95% CI = 1.41-2.94; p < 0.001) and mental health promotion activities (RR = 2.01; 95% CI = 1.06-3.82; p = 0.032), than those with low rankings. Although on-site and online occupational health services increased, home workspace assessments did not. Conclusion: Our findings highlight significant upward trends in the disclosure of telework measures following the issuance of government guidelines. Corporate governance is significantly associated with the implementation of occupational health measures. Amid the evolution of teleworking, both government guidelines and corporate governance have become essential for shaping work arrangements and ensuring workforce well-being.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.1D
• /
• pp.25-32
• /
• 2009

Currently, various types of TDM (Transportation Demand Management) policies are being studied and implemented in an attempt to overcome the limitations of supply oriented policies. In this context, this paper addressed issues of effectiveness and possible domestic implementation of the HOT lane. The possible site of implementation selected for this simulation study is part of the Kyung-bu freeway, where a dedicated bus lane is currently being operated. Minimum length of distance required in between interchanges and access points of the HOT lane for vehicles to safely enter and exit the lane, and traffic management policies for effectively managing the weaving traffic trying to enter and exit the HOT lane were presented. A 5.2km section of freeway from Ki-heuing IC to Suwon IC and a 8.3km section from Hak-uei JC to Pan-gyo JC have been selected as possible sites of implementation for the HOT lane, in which congestion occurs regularly due to the high level of travel demand. VISSIM simulation program has been used to analyze the effects of the HOT lane under the assumption that one-lane HOT lane has been put into operation in these sections and that the lane change rate were in between 5% to 30%. The results of each possible scenario have proven that overall travel speed on the general lanes have increased as well by 1.57~2.62km/h after the implementation of the HOT lane. It is meaningful that this study could serve as a basic reference data for possible follow-up studies on the HOT lane as one effective method of TDM policies. Considering that the bus travel rate would continue increase and assuming the improvement in travel speed on general lanes, similar case study can be implemented where gaps between buses on bus lane are available, as a possible alternative of efficient bus lane management policies.

• Journal of Korean Society for Atmospheric Environment
• /
• v.34 no.4
• /
• pp.542-553
• /
• 2018

Since many previous studies reported the health effect of air pollution and indicated traffic as a major pollution source, significant policy efforts have been made to control traffic to reduce air pollution. However, there have been few studies that evaluated such policy implementation. In Seoul, Korea, the exclusive median bus lane system was implemented in 2004, and the metropolitan government applied air pollution reduction policies such as conversion of diesel buses to compressed natural gas buses and installation of emission control devices. This paper aimed to investigate the impact of the exclusive median bus lane system on air pollution reduction. Using hourly concentrations of particulate matter ($PM_{10}$) and nitrogen dioxide ($NO_2$) measured at 131 regulatory monitoring sites in Seoul and Gyeonggi-do for 2001-2014, we calculated annual and daily average concentrations at each site. We assessed the impact of the policy using differences-in-differences analysis by annual and daily average models after adjusting for geographic and/or meteorological variables. This method divides population into treatment and control groups with and without policy application, and compares the difference between the two time periods before and after the policy implementation in the treatment group with the difference in the control group. We classified all monitoring sites into treatment and control groups using two definitions: 1) Seoul vs. Gyeonggi-do; 2) within vs. outside 300 meters from the median bus lane. Pre- and post-policy periods were defined as 2001-2005 and 2006-2014, and 2004 and 2014 in the annual and daily models, respectively. The decrease in $PM_{10}$ concentrations between the two periods across monitoring sites in the treatment group was larger by $1.73-5.88{\mu}g/m^3$ than in the control group. $NO_2$ also showed the decrease without statistical significance. Our findings suggest that an efficient public transport policy combined with pollution abatement policies can contribute to reduction in air pollution.

• The Transactions of the Korea Information Processing Society
• /
• v.5 no.12
• /
• pp.3047-3062
• /
• 1998

This paper deseribes the desihn and the implementation of the Realtime Transport Protocol(RTP)/ Rdaltime Control Protocol(RTCP) (RFC 1889,1890) that is used to transmit the audio/video data to any destination and to feedback the Quality of Service (QoS) information of the received media data to the sender, in the teleconferencing systems proposed by ITU-T. These protocols are implemented with multi thead technique and run on top of UDP/IP-Multicast through the socket interface as the underlying protocol. The upper layer is impelmented such that in can be accessed by the H245 comference control protocol. The RTP packetizes the digitized audio/video data from the encoder info a fixed format, and multieast to the participants. The RTCP monitors RTP packets and extracts the QoS values from it such as round-trip delay, jiter and packet loss to form RTCP packets and non periokically sends them to the sender site. In this Paper, we also descritx the study of measurement and analysis for QoS factors that observed on performing teleconferencing system over Internet. The results from this experiment is indicate that RTT and Jitter value are acceptable even entwork load is high. However, it appears that packet loss rate is high in daytime and most losses periods have length one or two.

• Korean Journal of Comparative Education
• /
• v.28 no.1
• /
• pp.51-87
• /
• 2018

The purpose of this study is to seek a measure to institutionalize the curriculum of Korean homeschooling by comparing and analyzing curriculums of homeschooling between the United States and South Korea. To do so, literature review was conducted to derive analysis criterion and curriculums of homeschooling between the United States and South Korea were compared and analyzed. The major findings of analyses are as follows. First, from the perspective of educational goal, homeschooling families of both countries are similar in which they preferentially seek private goal but also consider social goal as well. Second, in the perspective of educational content, a diversity in course of study, textbook and other education materials of homeschooling in the United States is substantially attained when Korean homeschooling families suffer shortage. Third, in terms of educational implementation, homeschooling of both countries attained an autonomy in instructional time and a diversity in instructional space and method, however, unlike homeschooling in the United States, homeschooling in South Korea is experiencing difficulties due to lack of homschooling organization, homeschooling co-ops and web-site space. Fourth, in the perspective of educational evaluation, homeschooling in South Korea, unlike its comparison target, has not been certified as a formal education as well as not been accepted from universities. Based on these analysis results, conclusion and discussion have been proposed.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.15 no.4
• /
• pp.273-280
• /
• 2012

The numerical simulation using the Lattice Boltzmann Method in the field of computational fluid dynamics becomes wider in the engineering applications because of its simplicity of update rules compared to the conventional Navier-Stokes solvers. Here, a two-dimensional D2Q9 LB model is numerically tested with a few new computational treatment on the free surface. The single relaxation time is applied under the gravitational field where applied only in the higher density fluid because of its big density difference. At the free surface, the reconstruction techniques in combination with boundary conditions is adopted in order to get some distribution function coming into the fluid site from the air one, and surface tension, early stable test for the gravitional field is considered in it. With the implementation of the gravitational profile, conserving the overall mass and grid dependency are observed during the calculations and freesurface advance track is well captured with an experiment.