• Environmental Analysis Health and Toxicology
• /
• v.17 no.3
• /
• pp.253-259
• /
• 2002

The phototoxicity inhibitory activity of 15 natural products having antiinflammatory effect was screened by three in vitro methods: yeast growth inhibition test with Candida albicans, RBC photohemolysis and MTT assay. We induced phototoxic reaction by irradiating UVA (365 nm) on chlorpromazine (CPZ) that has been widely documented as phototoxic agent in clinical and experimental studies and then observed the effects of the natural products after treating them with CPZ. In yeast growth inhibition test, X. stramonium showed the inhibitory effect on the UVA phototoxicity and E. officinalis, Yeast, P. suffruticosa showed phototoxicity inhibitory effect in that their ％ hemolysis compared with control were 36.14${\pm}$ 2.69, 42.82${\pm}$1.35, 36.41${\pm}$0.48 on UVA. In MTT assay, all tested natural products increased cell viability compared with the control.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2004.10a
• /
• pp.43-51
• /
• 2004

As the slenderness ratio of a high-rise building increases, the lateral load resisting system for the building is more often determined by serviceability design criteria. In serviceability design, the maximum drift and the level of vibration are controlled not to exceed the design criteria. Even though many drift method have been developed in various forms, no practical design method for wind induced vibration has been developed so far. Structural engineers rely upon heuristic or experience in designing wind induced vibration. Development of practical design method for wind induced vibration is required. Generally, wind induced acceleration responses are depending on several variables such as the weight density of a building, damping ratio, the natural period, and etc.. All parameters except the natural period or frequency are usually out of reach for structural engineers, then the wind acceleration response may be proportioned to the natural period. Therefore, in this paper, a wind induced vibration design method based on frequency control technique for high-rise is proposed. The method is applied to vibration design of a 25-story office building for performance evaluation.

• Journal of Internet Computing and Services
• /
• v.23 no.1
• /
• pp.19-29
• /
• 2022

Natural user interface (NUI) is used for the natural motion interface without using a specific device or tool like a mouse, keyboards, and pens. Recently, as non-contact sensor-based interaction technologies for recognizing human motion, gestures, voice, and gaze have been actively studied, an environment has been prepared that can provide more diverse contents based on various interaction methods compared to existing methods. However, as the number of sensors device is rapidly increasing, the system using a lot of sensors can suffer from a lack of computational resources. To address this problem, we proposed a real-time multi-device control system for natural interactive platform. In the proposed system, we classified two types of devices as the HC devices such as high-end commercial sensor and the LC devices such astraditional monitoring sensor with low-cost. we adopt each device manager to control efficiently. we demonstrate a proposed system works properly with user behavior such as gestures, motions, gazes, and voices.

• Korean journal of applied entomology
• /
• v.58 no.4
• /
• pp.319-320
• /
• 2019

We have developed simple and reliable new habitat plants system with natural enemies names as "Natural Enemy in First (NEF)" method. As a result, NEF without monitoring and release of just natural enemy with monitoring showed higher bio-control effects, i.e., 83% and 70%, respectively than environmental friendly agricultural material (EFAM) treatment. In addition, the average population density of predatory mites on NEF method was higher (three times) than other treatment.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2002.11a
• /
• pp.49.1-49
• /
• 2002

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2002.11a
• /
• pp.48-49
• /
• 2002

• Proceedings of the Zoological Society Korea Conference
• /
• 2003.08a
• /
• pp.204.4-204
• /
• 2003

No Abstract, See Full Text

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2002.10a
• /
• pp.467-474
• /
• 2002

Semiactive control systems have received considerable attention for protecting structures against natural hazards such as strong earthquakes and high winds, because they not only offer the reliability of passive control systems but also maintain the versatility and adaptability of fully active control systems. Among the many semiactive control devices, magnetorheological (MR) fluid dampers comprise one particularly promising class. In the field of civil engineering, much research and development on MR fluid damper-based control systems has been conducted since B. F. Spencer first introduced this unique semiactive device to civil engineering applications in mid 1990s. In 2001, MR fluid dampers were applied to the full-scale in-service civil engineering structures for the first time. This state-of-the-art paper includes a detailed literature review of control algorithms considering the characteristics of fm fluid dampers. This review provides references to semiactive control systems using MR fluid dampers. The MR fluid damper-based semiactive control systems are shown to have the potential for mitigating the responses of full-scale civil engineering structures under natural hazards.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.16 no.5
• /
• pp.1042-1047
• /
• 2002

Recently, many natural medicines, which have advantage of less side effects and possibility of long-term use, have been studied for their capacity and effects of anti-bacterial, anti-inflammatory and regenerative potential for periodontal tissues. Cortex Eucommiae, Eupoly phaga, Semen Cuscutae, Halloysitum Rubrum have been traditionally used as medicines for treatment of bone disease in Korea. The objective of the present study is to examine the ability of alkaline phosphatase (ALP) activity in human fetal osteoblast cell line (hFOB1) with several natural medicines. hFOB1 added DMEM/F-12 were cultured with dexamethasone as a positive control, and with each natural medicine. ALP activity was measured by spectrophotometer for enzyme activity and naphthol AS-Bl staining was performed for morphometry. All of the natural medicines induced a higher ALP activity compared to negative control, especially, Cortex Eucommiae increased an ALP activity in all experimental groups (p<0.05). In naphthol AS-Bl staining, all of the natural medicines of this study increased the stained area compared to negative control. Especially, Cortex Eucommiae and Eupoly phaga showed statistical significance compared to negative control (p<0.05). These results indicate that Cortex Eucommiae, Eupoly phaga, Semen Cuscutae, Halloysitum Rubrum have an inducing ability of ALP synthesis on osteoblasts.

• Smart Structures and Systems
• /
• v.3 no.2
• /
• pp.147-172
• /
• 2007

The present paper is concerned with the design of distributed sensors and actuators. Strain type sensors and actuators are considered with their intensity continuously distributed throughout a continuous structure. The sensors measure a weighted average of the strain tensor. As a starting point for their design we introduce the concept of collocated sensors and actuators as well as the so-called natural output. Then we utilize the principle of virtual work for an auxiliary quasi-static problem to assign a mechanical interpretation to the natural output of the sensors to be designed. Therefore, we take the virtual displacements in the principle of virtual work as that part of the displacement in the original problem, which characterizes the deviation from a desired one. We introduce different kinds of distributed sensors, each of them with a mechanical interpretation other than a weighted average of the strain tensor. Additionally, we assign a mechanical interpretation to the collocated actuators as well; for that purpose we use an extended body force analogy. The sensors and actuators are applied to solve the displacement tracking problem for continuous structures; i.e., the problem of enforcing a desired displacement field. We discuss feed forward and feed back control. In the case of feed back control we show that a PD controller can stabilize the continuous system. Finally, a numerical example is presented. A desired deflection of a clamped-clamped beam is tracked by means of feed forward control, feed back control and a combination of the two.