• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.272-275
• /
• 2003

Theodolite measurement system is non-contacted 3-dimensional measurement system. The system accuracy is 0.5 mm or better for distance 0 ~ 100 m. And the system is used for the measurement of a product for middle and large scale. This study was performed for finding the measurement error factors of the system. We could know that the main error factors are temperature, illumination and expertness. And we could find the measurement errors are $\pm$ 0.045 mm at temperature conditions is 2$0^{\circ}C$ and $\pm$ 0.012 mm at illumination condition is 300 lux. Also the results had significant differences by combinations of operator's expertness.

• Interaction and multiscale mechanics
• /
• v.2 no.3
• /
• pp.235-261
• /
• 2009

This study illustrates the differences between the elasto-plastic cap model and Lade's model with Cosserat rotation through the analyses of two large-scale geosynthetic-reinforced soil (GRS) retaining wall tests that were brought to failure using a monotonically increasing surcharge pressure. The finite element analyses with Lade's model were able to reasonably simulate the large-scale plane strain laboratory tests. On average, the finite element analyses gave reasonably good agreement with the experimental results in terms of global performances and shear band occurrences. In contrast, the cap model was not able to simulate the development of shear banding in the tests. In both test simulations the cap model predicted failure loads that were substantially less than the measured ones.

• Korean Journal of Organic Agriculture
• /
• v.21 no.1
• /
• pp.49-59
• /
• 2013

The Purpose of this paper is to analysis on farmer's awareness and satisfaction level of the project for developing large-scale environment-friendly agricultural districts (LSEAD). To analysis farmer's awareness and satisfaction level, a series of farm household surveys were conducted on farmers, take part in the project for developing LSEAD. The sample size of the survey is 80 respectively. As a survey result, awareness and practical use of facilities & equipment shows a little different outcome. Satisfaction level of the project for developing LSEAD is summarized as follows. Influence on disposal of livestock excretions and farmer's consciousness change appears 4.47 and spreading environment-friendly agriculture 4.44, distribution of environment-friendly agricultural product 4.33, and demand of environment-friendly agricultural materials 4.04. In order to sustainable development of LSEAD, a governance system should be established.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2003.09a
• /
• pp.462-466
• /
• 2003

This study was conducted to examine the potential of biosparging process in removing diesel contaminated soil and groundwater. The experiment was carried out lab-scale biosparging reactor and the biodegradation rate of diesel was evaluated as function of air injection rate and pattern. When renter was operated as air injection rate of 1000$m\ell$/min and pulsed air injection(15min pulse, 15min downtime), DO concentration in the renter was higher than another operating condition. The evidence for biodegradation of diesel was the $O_2$ utilization and $CO_2$ product following the cessation of sparging. Especially, air injection rate of 2000$m\ell$/min and pulsed air injection(15min pulse, 15min downtime) enhanced the diesel biodegradation during the operating. After 120day, the biodegradation rate of diesel was decreased as the lack of carbon source.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.13 no.2
• /
• pp.61-68
• /
• 2004

A non-contact precision measurement system is a theodolite system, a laser tacker and a photogrammetry system etc. Nowadays, the system reaches to a limit of measurement accuracy required from industrial product of middle and large scale. The one of the solutions for this problem is to maximize the accuracy of the existing measurement system. According to it we performed the study far a measurement accuracy of theodolite system when the distance between two theodolites is changed 1m to 5m. We could blow that the changes of distance affect the measurement accuracy of theodolite system and that the maximum measurement accuracy is $\pm$ 0.02 mm on theodolite distance 3∼4 m.

• Korean Journal of Organic Agriculture
• /
• v.11 no.2
• /
• pp.43-60
• /
• 2003

Recently. together with consumers' increasing concerns on food safety and environmental issues. there is increasing demand on the environmentally friendly agricultural products such as organic products. At present, Japan. as a biggest net importing country of the agricultural products. is a market of the international-scale in the organic product marketing. Also. it is expected that the possibility of market expansion in the future is very high. According to the 2000 agricultural census in Japan. the number of the environment-friendly agricultural farmers were 501.556 householders. This number is about 145 percent higher than that of the 1996 results of 204,600 householders. Organic products in Japan were mainly marketed through the producer and consumer cooperation, producers' cooperation, specialized marketing company etc. However, along with the department store, big supermarket and others' participation in the market recently, the marketing channels are diversified. As of October 1999, market sales of the organic products were estimated about 350 billion yen. It is expected that organic certification system, organic products import, resturant industry scale and others will be more influential factors on the market expansion of the organic products in the future.

• Proceedings of the KAIS Fall Conference
• /
• 2006.05a
• /
• pp.294-297
• /
• 2006

Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2005.05a
• /
• pp.278-281
• /
• 2005

Today, manufacturing capability at the micro or nano scale production field is requested strongly in view of parts and product miniaturization. Miniaturized parts and products will introduce lots of benefits in terms of high precision functionality and low energy consumption. This paper presents the results of micro milling machine tool development for micro machining process. Finite element analysis has been performed to know the relationship between design dimensional variables and structural stiffness in terms of static, dynamic, thermal aspects. Performance evaluation through machining has been tested and discussed for achievable machining characteristics.

• Computers and Concrete
• /
• v.13 no.4
• /
• pp.501-516
• /
• 2014

The purpose of this study was to investigate the performance of precast concrete pier cap system. The proposed precast pier cap provides an alternative to current cast-in-place systems, particularly for projects in which a reduced construction time is desired. Five large-scale pier cap specimens were constructed and tested under quasistatic monotonic loading. The computer program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) was used for the analysis of reinforced concrete structures. A bonded tendon element is used based on the finite element method, and can represent the interaction between the tendon and concrete of a prestressed concrete member. A joint element is used in order to predict the inelastic behaviors of segmental joints with a shear key. This study documents the testing of the precast concrete pier cap system under monotonic loading and presents conclusions and design recommendations based on the experimental and analytical findings. Additional full-scale experimental research is needed to refine and confirm design details, especially for actual detailing employed in the field.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1713-1715
• /
• 2007

Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. We have advanced the framework of the multiple time scale congestion control and showed its effectiveness at enhancing performance for the rate-based feedback control. Our contribution is threefold. First, we define a modular extension of the TCP-a function called with a simple interface-that applies to various flavours of the TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.