• Asian-Australasian Journal of Animal Sciences
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• v.31 no.12
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• pp.1881-1889
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• 2018

Objective: In dryland areas of China, alfalfa hay (AH) is a possible substitute for concentrate feed for beef cattle. To evaluate the potential benefits of this substitution, we studied the effect of the ratio of AH intake to total dry matter (DM) intake on average daily body-weight gain (ADG), dietary energy utilization status, and economic benefit in Gansu province. Methods: In each of two feeding trials in 2016 (trial 1 [T1], July 3 to 17; trial 2 [T2], August 15 to September 23), crossbred male Simmental calves were allocated to low AH (LA), medium AH (MA), and high AH (HA) feeding groups (n = 4 per group). The target ADG was set as 1 kg for both trials. In a one-way-layout design based on conventional feeding practices in the province, calves received diets containing the different AH amounts, with a constant ratio of corn stover:total DM and decreasing rations of concentrate feed proportional to the increase in AH. Calves in T1 received AH at 15% (T1-LA), 23% (T1-MA), or 31% (T1-HA) of their dietary DM allowances; those in T2 received 9% (T2-LA), 24% (T2-MA), or 34% (T2-HA) AH. Results: Among the T1 groups, both ADG and economic benefit were highest in T1-LA; whereas in T2, they were higher in the T2-LA and T2-MA groups than in T2-HA. Energy digestibility did not significantly differ among the groups in either trial. The dietary AH inclusion ratios of 14% in the warm season and 8% to 21% in the cool season appeared to yield optimal ADG, metabolizable energy intake, and economic benefit. Conclusion: Low-level inclusion of AH, ranging from 8% to 21%, is a practical approach for beef cattle feeding. This modified feeding regimen likely will promote increased growth performance during the fattening stage of beef steers in dryland areas of Gansu province, China.

• Tunnel and Underground Space
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• v.28 no.6
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• pp.528-546
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• 2018

Cases of TBM tunnelling have been consistently increasing worldwide. In many recent subsea and urban tunnelling projects, TBM excavation has been preferably considered due to its advantages over drill and blast tunnelling. Difficult ground conditions are highly probable to appear in subsea and urban tunnels because of the shallow working depth and alluvial characteristics. Under the difficult ground conditions, ground reinforcement measures should be considered including grouting, while it is of great importance to select the optimal grout material and injection method to cope with the ground condition. The benefits from TBM excavation, such as fast excavation, increased safety, and reduced environmental impact, can be achieved by applying appropriate ground reinforcement with the minimum overrun of cost and time. In this report, various grouting methods were reviewed so that they can be applied in difficult ground conditions. In addition, domestic and international cases of successful ground reinforcement for difficult grounds were introduced for future reference.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.1
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• pp.85-91
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• 2021

In contrast to standard train tracks, tramlines are often set along public roads, with trams running among pedestrians and other vehicles. In some cities and towns, trams and buses share the same routes and stations. Under the current investment appraisal system, trams are classified into light rail when predicting traffic demand and calculating benefits, but in the case of non-capital areas, it is notable that the origin-destination and transit lines of buses are not provided in the Korea Transport Database distribution data. Due to this problem, it is difficult to reflect proper mode changing behaviors between route buses and trams. This study examines the impact on tramlines of bus routes that are not currently considered in non-capital areas. Following an analysis of the effect of tram projects according to whether bus routes are considered or not, an improvement in methodology is proposed. Through this study, it is expected that the investment appraisal system for the planning of new tramlines will be improved in the future.

• Journal of Auto-vehicle Safety Association
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• v.14 no.4
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• pp.43-52
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• 2022

Recently, the government has been expanding the supply of hydrogen vehicles according to the roadmap for vitalizing the hydrogen economy, but is developing safety assessment and inspection technology for the relevant vehicles. This study analyzed the prevention of hydrogen bus accidents' economic effect that arises from the application and development of large-capacity CHSS oil pressure repetition-test assessment technology, hydrogen bus internal chamber pressure transmission and emission volume inspection technology, among various technologies capable of assessing the safety of a hydrogen bus fuel system. To this end, the contingent valuation method (CVM), one of the value evaluation methods of non-market goods, was applied to investigate users' willingness to pay for each inspection technology. The survey for users' willingness to pay was conducted by attaching posters to promote surveys on the internet and within buses to the entire public. As a result of the analysis, the average WTP of the hydrogen bus internal chamber pressure transmission volume inspection technology was 25.3 KRW, the average WTP of the hydrogen bus internal chamber pressure emission volume inspection technology was 18.6 KRW, and the average WTP of the large-capacity CHSS oil pressure repetition-test assessment technology was measured at 16.7 KRW. In addition, the costs and benefits of the introduction of the relevant inspection technology were defined through the interviewing of experts at related research institutions and businesses. As a result of conducting an economic analysis (4.5% discount rate) according to the development of each inspection technology, economic feasibility was seen in all assessment and inspection technologies. As much as the technology is indispensable for the safe use of hydrogen buses, it shows that investment in related technology is very necessary in the future. However, because it was decided that the relevant analysis will differ according to the distribution rate of hydrogen buses, further analysis following this future distribution rate of hydrogen buses is needed, and future users should be made clearly aware of the safety and environmental nature of the technology.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.4
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• pp.343-350
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• 2022

The computerization project for underground facilities in Korea began in earnest after the city gas explosion in Seoul in 1994, and the Daegu subway explosion in 1995. As such a large-scale gas explosion accident caused enormous economic loss including human casualties and potential benefits, the need for computerized for efficient management of underground facilities was greatly emphasized in society. Meantime, computerization of underground facilities has been carried out according to the basic plan for building national geographic information system. In this study, problems were identified based on the current status of construction and management of underground facility information, as well as laws and regulations, and directions for establishing quality standards were presented. In addition, construction work standards such as 「Public Survey Work Regulations」, design standards, standard specifications, and technical specifications, gas technology standards, design standards, and communication works so that underground facility information can be linked and utilized in construction work by examining the linkage of the underground facilities, the targets that can be used for quality level information on underground facilities were derived, and a proposal to revise the construction standards was presented. In the future, if the quality standards are established, it is expected that the accuracy and utilization in the construction field will be increased.

• Journal of the Korean Society of Floral Art and Design
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• no.42
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• pp.37-62
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• 2020

The earth is a natural material that has natural healing power,,as a natural ingredient, it brings environmental friendliness, emotional. In this Research, for one of the methods to expand the benefits as a healing space, Construction of the Earth design and earth construction methods have been actively used for effectiveness of the Earth in the construction of the interior with the oriental medical clinic. By utilizing the concept of biophilic design as a healing environment design, symbolizing nature such as color, light, plants, flowers, and natural materials such as earth and wood was directed as oriental medicine interiors. In addition, the space was divided according to the movement of patients and used different Earth construction method to each of the space for the distinction and differentiation according to the characteristics of each space. At this time, the Earth was constructed with materials and finishing materials that meet the highest grade of HB (Healthy Building), an eco-friendly building material certification grade without additives, so that the interior and medical treatment concept can be done at the same time. By using Earth as the basis of elements in the construction, and the design of healing space, patient the concept of Biophillic as a healing environment design. This may serve as a technical, aesthetic, and cultural basis for constructing a healing space by Earth in the future-oriented alternative, it may lead to necessity of eco-friendly and ecological architecture, and it may be an opportunity to expand the application area of earth in architectural design.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.30-31
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• 2009

Early detection of schedule delay in field construction activities is vital to project management. It provides the opportunity to initiate remedial actions and increases the chance of controlling such overruns or minimizing their impacts. This entails project managers to design, implement, and maintain a systematic approach for progress monitoring to promptly identify, process and communicate discrepancies between actual and as-planned performances as early as possible. Despite importance, systematic implementation of progress monitoring is challenging: (1) Current progress monitoring is time-consuming as it needs extensive as-planned and as-built data collection; (2) The excessive amount of work required to be performed may cause human-errors and reduce the quality of manually collected data and since only an approximate visual inspection is usually performed, makes the collected data subjective; (3) Existing methods of progress monitoring are also non-systematic and may also create a time-lag between the time progress is reported and the time progress is actually accomplished; (4) Progress reports are visually complex, and do not reflect spatial aspects of construction; and (5) Current reporting methods increase the time required to describe and explain progress in coordination meetings and in turn could delay the decision making process. In summary, with current methods, it may be not be easy to understand the progress situation clearly and quickly. To overcome such inefficiencies, this research focuses on exploring application of unsorted daily progress photograph logs - available on any construction site - as well as IFC-based 4D models for progress monitoring. Our approach is based on computing, from the images themselves, the photographer's locations and orientations, along with a sparse 3D geometric representation of the as-built scene using daily progress photographs and superimposition of the reconstructed scene over the as-planned 4D model. Within such an environment, progress photographs are registered in the virtual as-planned environment, allowing a large unstructured collection of daily construction images to be interactively explored. In addition, sparse reconstructed scenes superimposed over 4D models allow site images to be geo-registered with the as-planned components and consequently, a location-based image processing technique to be implemented and progress data to be extracted automatically. The result of progress comparison study between as-planned and as-built performances can subsequently be visualized in the D4AR - 4D Augmented Reality - environment using a traffic light metaphor. In such an environment, project participants would be able to: 1) use the 4D as-planned model as a baseline for progress monitoring, compare it to daily construction photographs and study workspace logistics; 2) interactively and remotely explore registered construction photographs in a 3D environment; 3) analyze registered images and quantify as-built progress; 4) measure discrepancies between as-planned and as-built performances; and 5) visually represent progress discrepancies through superimposition of 4D as-planned models over progress photographs, make control decisions and effectively communicate those with project participants. We present our preliminary results on two ongoing construction projects and discuss implementation, perceived benefits and future potential enhancement of this new technology in construction, in all fronts of automatic data collection, processing and communication.

• Journal of Internet of Things and Convergence
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• v.9 no.2
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• pp.61-69
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• 2023

In recent years, due to heightened environmental awareness, Electric Power Steering (EPS) has been increasingly adopted as the steering control unit in manufactured vehicles. This has had numerous benefits, such as improved steering power, elimination of hydraulic hose leaks and reduced fuel consumption. However, for EPS systems to respond to actions, sensors must be employed; this means that the consistency of the sensor's linear variation is integral to the stability of the steering response. To ensure quality control, a reliable method for detecting defects and assessing linearity is required to assess the sensitivity of the EPS sensor to changes in the internal design characters. This paper proposes a data-driven defect and linearity assessment monitoring system, which can be used to analyze EPS component defects and linearity based on vehicle speed interval division. The approach is validated experimentally using data collected from an EPS test jig and is further enhanced by the inclusion of a Graphical User Interface (GUI). Based on the design, the developed system effectively performs defect detection with an accuracy of 0.99 percent and obtains a linearity assessment score at varying vehicle speeds.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.165-176
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• 2022

To raise awareness of carbon reduction in climate change, the Korea Forest Service has developed and adopted a forest carbon offset program, which aims to reduce carbon levels based on forest management. However, to maintain the forest carbon offset program, challenges such as the lack of a forest monitoring system to manage and maintain the program, must be faced. In this context, we investigated the limitations of conducting forest carbon offset programs using a number of interview techniques, including in-depth interview and questionnaire survey methods. The questionnaire surveys were developed based on the results of a literature review along with a preinterview and in-depth survey of the people in charge of the forest carbon offset program. The Irving Seidman technique was adopted for the in-depth interviews. Additionally, descriptive and frequency analyses were conducted to identify the characteristics of perception. Lastly, logistic regression was used to identify the limiting factors that affect the willingness to perform forest carbon offset monitoring activity. Results showed that the project managers or people in charge of the forest carbon offset program lacked expertise in forest carbon offset programs, which negatively affected their willingness to perform monitoring activity. Additionally, the study revealed a number of limiting factors that hindered the monitoring of forest carbon offset projects. Improving understanding using the approaches presented in this study may contribute to increasing the benefits associated with the forest carbon offset program in South Korea.

• Environmental and Resource Economics Review
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• v.32 no.2
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• pp.107-126
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• 2023

This study analyzes the financial efficiency of the early scappage support system using the benefit and cost analysis. To do so, we use comprehensive administrative data on the early scrappage of old diesel vehicles. The result shows that the benefit-cost ratio was greater than 1 before 2020, but it appeared to be less than 1 after 2020. This indicates that despite recent reforms to increase the subsidy of early scrappage of old diesel vehicles, the rate of the benefit of air quality improvement is not as fast as the increase in system operation cost of this system. The benefit of air quality improvement depends on how much the operating period is shortened due to early scrappage support system. The earlier this period is brought forward, the more likely it is that the benefits of early scrappage will exceed the costs. Upon examining the results of this study, it was found that when the scrappage timing is brought forward by 5 years, the B/C for 98% of the samples becomes 1, greatly securing financial efficiency. Therefore, it is important for the government to reform the system so that it can influence the decision of old diesel vehicle owners on the timing of scrappage.