• International conference on construction engineering and project management
• /
• 2020.12a
• /
• pp.249-256
• /
• 2020

Historical construction health and safety (H&S) challenges, in terms of a range of resources and issues, continue to be experienced, namely design process-related hazards are encountered on site, workers are unaware of the hazards and risks related to the construction process and its activities, activities are commenced on site without adequate hazard identification and risk assessments (HIRAs), difficulty is experienced in terms of real time monitoring of construction-related activities, workers handle heavy materials, plant, and equipment, and ultimately the experience of injuries. Given the abovementioned, and the advent of Industry 4.0, a quantitative study, which entailed the completion of a self-administered questionnaire online, was conducted among registered professional (Pr) and candidate Construction H&S Agents, to determine the potential of Industry 4.0 to contribute to resolving the challenges cited. The findings indicate that Industry 4.0 technologies such as augmented reality (AR), drone technology, virtual reality (VR), VR based H&S training, and wearable technology /sensors have the potential to resolve the cited H&S challenges as experienced in construction. Conclusions include that Industry 4.0 technologies can finally address the persistent H&S challenges experienced in construction. Recommendations include: employer associations, professional associations, and statutory councils should raise the level of awareness relative to the potential implementation of Industry 4.0 relative to H&S in construction; case studies should be documented and shared; tertiary construction management education programmes should integrate Industry 4.0 into all possible modules, especially H&S-related modules, and continuing professional development (CPD) H&S should address Industry 4.0.

• International Journal of High-Rise Buildings
• /
• v.12 no.4
• /
• pp.343-350
• /
• 2023

With the advent of the recent Fourth Industrial Revolution, efforts are vigorously underway to comprehend the new paradigm of Construction 4.0, following in the footsteps of Industry 4.0, and to establish novel production systems. The necessity and significance of technological advancements in the field of construction automation and robotics, a pivotal component for Construction 4.0, are being emphasized. This paper aims to discuss the concept of construction automation and robotics, encompassing its past, present, and future prospects. Particularly, it reviews the six relevant papers featured in the June 2022 special issue of IJHRB, along with discussions on the integration of cutting-edge ICT technologies and R&D in the realm of automation and robotics. With the progression of ICT technology, the domain of construction automation and robotics is anticipated to play a substantial role in the realization of Construction 4.0 and smart construction through more dynamic convergence in technological development.

• Journal of Korean Society of Forest Science
• /
• v.101 no.3
• /
• pp.480-487
• /
• 2012

This study was conducted to search the effects of debris barrier on the benthic macroinvertebrate. Gimcheon was selected as the survey site as it has relatively stable ecosystem with constantly running water. The survey was conducted 6 times before and after the construction of debris barrier from February in 2009 to October in 2010. In the first survey before construction, the identified species were 36 species belonged to 22 families, 9 order, 4 class, and 4 phylum. The figure slightly decreased to 30 species belonged to 18 families, 7 order, 2 class, and 2 phylum in the sixth survey after construction. Before construction, occupation ratio of EPT taxa was showed in the following order: Ephemeroptera (50.0%, 85.0%), Trichoptera (35.3%, 10.0%), and Plecopteran (14.8%, 5.0%). After construction, it was showed in the following order: Trichoptera (50.3%, 68.0%), Ephemeroptera (42.1%, 29.4%), and Plecopteran (7.5%, 2.7%). Ephemeroptera was the highest before construction. Trichoptera increased rapidly after construction. The Diversity, Richness, Evenness, and Dominance indices were all turned low in the second survey right after the construction. However, each index tended to increase with the course of time. In Functional Feeding Groups, GC type was the highest of 60.7% before construction. After construction, SC(53.1%) and FC(35.4%) increased rapidly and they became stabilized since the third survey. The result of this study reveals that debris barrier greatly affects the Aquatic Ecosystem right after its construction, but the system becomes stable and returns to normal with the course of time (about 18 months). Therefore, the study considering various influence factors such as time is required to recover completely through further long-term monitoring.

• International Journal of Concrete Structures and Materials
• /
• v.4 no.1
• /
• pp.3-8
• /
• 2010

This paper present the results of investigation on the use of rice husk ash as a partial substitute for cement in construction. One hundred and eighty specimens of concrete cubes were cast. 0, 5, 10, 15, and 20% partial replacement of cement with rice husk ash were carried at 1:2:4 mixes by weight with 0.60, 0.65, 0.70 water/cement ratio. The results indicated that compressive strengths of cubes at 0.6, water/cement were higher than 0.65 and 0.70. Also 5% partial replacement cement with rice husk ash at $28^{th}$ day average compressive strength value of $25.4\;N/mm^2$ compared well with 0% partial replacement of cement with rice husk ash of $26.28\;N/mm^2$. This shows that at 5% partial replacement of cement with rice husk ash can be used for structural concrete and at 15% replacement or more it can be used for non - structural construction works or light weight concrete construction. The cost analysis shows substantial amount of savings for the country.

• Journal of Broadcast Engineering
• /
• v.27 no.3
• /
• pp.391-401
• /
• 2022

As deep learning-based object detection and recognition research have been developed recently, the scope of application to industry and real life is expanding. But deep learning-based systems in the construction system are still much less studied. Calculating materials in the construction system is still manual, so it is a reality that transactions of wrong volumn calculation are generated due to a lot of time required and difficulty in accurate accumulation. A fast and accurate automatic drawing recognition system is required to solve this problem. Therefore, we propose an AI-based automatic drawing recognition accumulation system that detects and recognizes steel materials in construction drawings. To accurately detect steel materials in construction drawings, we propose data augmentation techniques and spatial attention modules for improving small object detection performance based on YOLOv4. The detected steel material area is recognized by text, and the number of steel materials is integrated based on the predicted characters. Experimental results show that the proposed method increases the accuracy and precision by 1.8% and 16%, respectively, compared with the conventional YOLOv4. As for the proposed method, Precision performance was 0.938. The recall was 1. Average Precision AP_0.5 was 99.4% and AP_0.5:0.95 was 67%. Accuracy for character recognition obtained 99.9.% by configuring and learning a suitable dataset that contains fonts used in construction drawings compared to the 75.6% using the existing dataset. The average time required per image was 0.013 seconds in the detection, 0.65 seconds in character recognition, and 0.16 seconds in the accumulation, resulting in 0.84 seconds.

• Journal of Wetlands Research
• /
• v.18 no.4
• /
• pp.394-403
• /
• 2016

This study was carried out to verify change and relationship between the concentration of chlorophyll-a and environmental factors including weather, water quality and discharge at before & after Gangcheon and Ipoh weir construction at Namhan river, based on the weather and water quality data provided by the measuring network. We classified the period of before & after weir construction by the cluster analysis with Ward's method, and also through the correlation analysis between the concentration of chlorophyll-a and environmental factors, the influence factors related with algae occurrence(Chlorophyll-a) were analyzed. The result by cluster analysis based on data of the total 12 factors (water temperature, rainfall, daylight, pH, DO, BOD, COD, T-N, $NH_3-N$, $NO_3-N$, T-P, $PO_4-P$) from 2005 to 2015 indicated a clear classification into two periods, before(2006-2007) & after (2012-2013) weir construction. After weir construction, class of BOD at Gangcheon weir was better than before, changed from II class to Ia class, and likewise class of BOD at Ipoh weir was improved from II-III class to Ia-IIclass. Also T-P and T-N concentration also were to be improved in general after weir construction. Concentraion of Chlorophyll-a afterGangcheon and Ipoh weir construction was to be decreased. However, frequency of algae warning was increased from 9 to 15 after Ipoh weir construction due to increasing of HRT and water temperature. After weirs construction, the result of correlation analysis between weather, water quality and discharge and concentration of chlorophyll-a indicated a positive correlation, order of BOD(0.579) > COD(0.413) > temperature(0.237), and a negative correlation, order of $NO_3-N$(-0.344) > T-N(-0.293) at Gangcheon weir. And there were likewise positive correlation, order of BOD(0.795) > pH(0.581) > Water temperature(0.422), and negative correlation, order of $NO_3-N$(-0.457) > T-N(-0.371) > $NH_3-N$(-0.326) > $PO_4-P$(-0.288) > Discharge(-0.213) after Ipoh weir construction. Although water quality after Ipoh weir construction was generally improved, increase of frequency of algae warning occurrence was influenced by change of water conditions such as reduction of the velocity, increase of HRT and water temperature, etc impacted strongly by change of the stream flow more than change of water environments after weir construction.

• Korean Journal of Construction Engineering and Management
• /
• v.23 no.3
• /
• pp.95-103
• /
• 2022

Recently, the fourth industrial revolution has a great influence on the development of many industries as well as the construction industry. Various technologies related to the industrial revolution 4.0, such as AI and big data, have gained much attention. However, little has been known about the importance and preparedness of stakeholders of the construction industry in Korea for the industry 4.0 technologies so far. This study revealed how the stakeholders perceive and prepare for industry 4.0 using a survey. In addition, collaboration potential score for each technology was calculated to find technologies with high potential for collaboration. Result is that the importance of the technologies was evaluated high in overall, but the preparedness and implementation in university education or business was evaluated low. Technologies with high potential for industry-university collaboration are AI/big data and 3D printing/3D scanning. This study can contribute to the training of industry 4.0 experts and improving preparedness, which would enable the innovation and application of industry 4.0 technologies in the construction industry.

• Hwankyungkyoyuk
• /
• v.18 no.1 s.26
• /
• pp.120-133
• /
• 2005

This study investigated the changes of consciousness and ambivalent attitudes about the important environmental issues among the teachers who enrolled the environmental education training. Experimental and control groups were composed with 47 and 30 person, respectively. Environmental issues were constructions of sea-wall, nuclear power plant and dam. Cronbach alpha of the self-developed questionnaire was $0.6909{\sim}0.8992$. Score were made with 5 Likert scales for consciousness, and with semantic differential half scale for ambivalent attitudes. Almost teachers(94.0% and 97.1%) have above 10 years teaching career. Strangers in environmental program were 53.2%. After environmental training, teachers' consciousness was significantly changed to negative about the construction of sea-wall for the farm field and industry complex area(p=0.019), and about the construction of dam for disaster like flood(p=0.026), and for adverse effects of citizen by fog(p=0.042). They were also significantly changed to negative about the construction of nuclear power plant for economical energy(p=0.004)', no-emission of greenhouse gases(p=0.033)', 'alternative energy(p=0.000)', 'destruction of ecology(p=0.052)' and 'social fear(p=0.009)'. The consciousness of teachers who have the experience of environmental training, were significantly changed to negative about the construction of nuclear power plant. Scores of teachers' ambivalent attitudes were made lower in experimental than control group about the construction of sea-wall and nuclear power plant. After education training, they were made lower so much as -10.0% in control, but higher much as +4.4% in experimental, and severely higher much as 86.5% in teachers who had experienced the environmental training about construction of sea-wall. Their scores were made lower so much as -3.3% in control, but much as -6.4% in control.

• KIEAE Journal
• /
• v.10 no.4
• /
• pp.111-116
• /
• 2010

The environmental management is essential for construction projects. The environmental management cost for construction projects is used for various purposes to control the environmental pollution and treat the wastes generated from the construction sites. Six construction cases were analyzed to compare the environmental management cost. The proportion of environmental management cost for total construction budget should be higher than 0.70% in redevelopment projects and 0.30% in newly constructed buildings, respectively, but every six construction cases did not meet the legal requirement. Redevelopment projects expanded more environmental management cost than the newly constructed projects especially in noise control and wastes treatment. In case of apartment construction projects, the proportion of environmental management cost of redevelopment buildings is 2.4 times higher than the newly constructed buildings, but in all cases, paid more attention to the noise and waste controlling measures than the wastewater treatment. It is needed to ensure the cost-effectiveness of environmental management for achieving the eco-friendly construction sites.

• Journal of the Korea Institute of Building Construction
• /
• v.10 no.4
• /
• pp.3-9
• /
• 2010

Fire resistance and material properties of high-strength concrete (W/B 21.5%, 28.5%) with OPC, BS and FA were tested in this study. Main factors of the test consisted of fiber mixing ratio and W/B. Two types of fiber (NY, PP) mixed with the same weight were used for the test. The fiber mixing ratios were 0%, 0.05%, 0.1%, and 0.2% of the concrete weight. After performing the test, Under the W/B level of 21.5% and 28.5%, the spalling was effectively resisted by using the high strength concrete with fiber mixing ratios of 0.05%~0.1%. Compressive strength, flowability and air content are similar those of the fiberless high-strength concrete with the same W/B.