• Journal of the Korean Geotechnical Society
• /
• v.33 no.1
• /
• pp.5-15
• /
• 2017

Skin friction may be one of the most critical factors in designing the prebored and precast pile. Special attention was given to the interface behavior of cement milk-surrounding soil during the installation of prebored and precast pile. Small-scale field model pile test was conducted for the case of single pile. The size and geometry of the small-scale field model piles were designed with pile length 1.3m, boring diameter 0.067 m. Quick maintain-load test was conducted for the cases of boring diameter 150, 125, 90, 86, 74 mm and water-cement ratio 90, 70, 60%. It was shown that the bearing capacity of the pile increased as the cement-water ratio and cement milk thickness increased. Considering the scale effect between the small-scale model test and the actual construction site, it was found that cement milk thickness of 0.1~0.4D (50~200 mm) was reasonable for the stability of the structure. Also, the proper cement paste water / cement ratio was about 70% when considering the results of this study and quality control.

• Journal of the Korean Solar Energy Society
• /
• v.27 no.3
• /
• pp.135-142
• /
• 2007

The model to predict flow duration characteristics and performance for small scale hydro power(SSHP) plants is studied to analyze the effects of rainfall condition. One existing SSHP plant was selected and performance characteristics was analyzed by using the developed model. The predicted results from the model developed show that the data were in good agreement with operational results of existing SSHP plant. The results show that both the scale parameter and the shape parameter have large effects on the performance of SSHP sites. And also it was found that the model developed in this study can be a useful tool to predict the performance of SSHP sites.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.2
• /
• pp.186-191
• /
• 2001

A crack with electrically impermeable surfaces in an electrostrictive material subjected to uniform electric loading is analysed. The effect of electric yielding on stress intensity factor is investigated by using a small scale yielding model and a strip yield zone model. Complete forms of electric fields and elastic fields are derived by using complex function theory. The electrical yield zone shapes for two models are different each other. The two models, however, predict similar yield zone sizes under the small scale yielding conditions. It is found that the influence of electric yielding on the stress intensity factor is insensitive to the modeling of the electrical yield zone shape.

• Journal of the Korea Institute of Building Construction
• /
• v.4 no.3
• /
• pp.101-108
• /
• 2004

The physical factor having a great influence among components of making values of profit model in apartment houses is equilibrium change of house and this study suggests an alternative of remodelling. It sets profit models including model dividing household of large scale into that of small scale using value making factor of apartment house and spatial composition techniques and model integrating households of small scale and converting them into those of large scale and finds that its economy is good as over 'average', evaluative value of economy is reduced as discount rate increases and economy of remodelling is superior.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2600-2608
• /
• 2011

The dynamic stability of railway vehicle has been one of the important issues in railway safety. The dynamic simulator has been used in the study about the dynamic stability of railway vehicle and wheel/rail interface. Especially, a small scale simulator has been widely used in the fundamental study in the laboratory instead of full scale roller rig which is not cost effective and inconvenient to achieve diverse design parameters. But the technique for the design of the small scale simulator for the fundamental study about the dynamic characteristics of the wheel-rail system and the bogie system has not been well developed in Korea. Therefore, the research about the development of the small scale simulator and the bogie has been conducted. As this paper, To predict the dynamic behavior of railway vehicle, we studied running stability test of 1/5 scaled bogie that similarity laws is applied using small scale derailment simulator. For the operation of the small scale derailment simulator, it is required to investigate the performance and characteristics of the system. This could be achieved by a comparative study between an analysis and an experiment. This paper presented the analytical model which could be used for verifying of the test results and understanding of the physical behavior of the dynamic system comprising the small scale bogie and the simulator.

• Research in Community and Public Health Nursing
• /
• v.12 no.3
• /
• pp.647-660
• /
• 2001

Forming health care management model in small-scale enterprises was the purpose of this study. For the purpose, we tried to investigate the characteristics of small-scale enterprises and analyzed the pattern of their health care management. The results are as follow: 1. The strength of health managing agency and technical supporting program lies in team approach by specialized manpower. However, if the liaison between each part of the organization is not smooth, the overall management will be very difficult. 2. Small scale enterprises are characterized by their short life after the establishment, use of rental building, lack of welfare facilities, weakness in sanitary management and aggregation of factories of similar type of industry. Because of these characteristics, it is very difficult to solve problem basically, such as improvement of working environment. Therefore, it is important to focus on health education and community based approach. 3. Many workers in small-scale factories are in middle and old age. They have health problems mainly related to personal habits. Implementation of an appropriate health promotion program is needed. 4. The number of workplaces, which should be managed by health managing agent. is increasing rapidly. But the number of health managing agent is limited. In the aspect of the requirement of manpower and equipment, training personal agent is more urgent than founding institutional agent. 5. The uniform method of health management hampers the choice of employer and workers. The types of provision of health management should be diversified. 6. For an efficient management, a frequent visit of personal agent and the following referral to a specialist should be done. The specialists in charge of secondary management are from the field of occupational medicine, occupational hygiene, ergonomics, etc. 7. The health management of small-scale facilities should have six components. They are community-based approach, multi-disciplinary cooperative system, program based on the need of recipient, forming partnership of employer and worker, change of lifestyle, and evidence-based program.

• Journal of the Korea Institute of Building Construction
• /
• v.23 no.6
• /
• pp.831-839
• /
• 2023

This study aims to develop a framework for an accident prediction model leveraging a deep neural network algorithm, specifically tailored for small-scale construction sites. Notably, the incidence of accidents in the construction sector is markedly higher compared to other industries, with a significant contribution from small-scale sites. The challenging nature of construction in urban settings, coupled with the increasing frequency of adverse weather conditions, is likely to escalate accident risks at these sites. Anticipating and mitigating accidents at small-scale construction sites is therefore crucial to decrease the overall industry accident rate. Consequently, this research introduces a Deep Neural Network-based model for forecasting accidents at small-scale construction sites. The framework and findings of this study are poised to serve as a guideline for the safety management of small-scale construction projects, ultimately aiding in the realization of safer, more sustainable construction practices at these sites.

• Journal of The Korean Association of Information Education
• /
• v.6 no.2
• /
• pp.154-162
• /
• 2002

In a small-scale class, children gradually lose interests in studying and develop negative and passive attitudes in class activities due to the uniform education. Although many cooperative instruction WBI models are studied and designed, there has not been any research on cooperative instruction model appropriate for a small-scale class. In this study, instructors participate in classes, each in connection with other small-scale classes, and WWW based cooperative instruction model, WIEZ, which can affect students' learning attitude on long-term basis, was designed and embodied. Currently, WIEZ is being under experimental test in three schools at Kyung-nam where instructors design classes, and students divided into groups participate in classes in this system.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.8 no.5 s.39
• /
• pp.35-43
• /
• 2004

Small-scale models have been frequently used for seismic performance tests because of limited testing facilities and economic reasons. However, there are not enough studies on similitude law for analogizing prototype structures accurately with small-scale models, although conventional similitude law based on geometry is not well consistent in the inelastic seismic behavior. When fabricating prototype and small-scale model of reinforced concrete structures by using the same material, added mass is demanded from a volumetric change and scale factor could be limited due to aggregate size. Therefore, it is desirable that different material is used for small-scale models. Thus, a modified similitude law could be derived depending on geometric scale factor, equivalent modulus ratio and ultimate strain ratio. In this study, compressive strength tests are conducted to analyze the equivalent modulus ratio of micro-concrete to normal-concrete. Then, equivalent modulus ratios are divided into multi-phase damage levels, which are basically dependent on ultimate strain level. Therefore, an algorithm adaptable to the pseudodynamic test, considering equivalent multi-phase similitude law based on seismic damage levels, is developed. Test specimens, consisted of prototype structures and 1/5 scaled models as a reinforced concrete column, were designed and fabricated based on the equivalent modulus ratios already defined. Finally quasistatic and pseudodynamic tests on the specimens are carried out using constant and variable modulus ratios, and correlation between prototype and small-scale model is investigated based on their test results. It is confirmed that the equivalent multi-phase similitude law proposed in this study could be suitable for seismic performance tests on small-scale models.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.7
• /
• pp.914-924
• /
• 2020

In this study we developed artificial network generation model, which can generate on-line social network. The suggested model can represent not only scale-free and small-world properties, but also can produce networks with various values of topological characteristics through controlling two input parameters. For this purpose, two parameter K and P are introduced, K for controlling the strength of preferential attachment and P for controlling clustering coefficient. It is found out on-line social network can be generated with the combinations of K(0~10) and P(0.3~0.5) or K=0 and P=0.9. Under these combinations of P and K small-world and scale-free properties are well represented. Node degree distribution follows power-law. Clustering coefficients are between 0.130 and 0.238, and average shortest path distance between 5.641 and 5.985. It is also found that on-line social network properties are maintained as network node size increases from 5,000 to 10,000.