• Natural Product Sciences
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• v.12 no.3
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• pp.166-173
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• 2006

Silymarin is an antihepatotoxic substance isolated from the fruits of silybum mariamum. Possibly due to their antioxidant and membrane stabilizing properties, the compounds was shown to protect various organs and cells against a number of insults (Kvasnicka et al., 2003). Among the main silymarin components, [silybin($SB_A,\;SB_B$, isosilybin ($ISB_A,\;ISB_B$) silydianin (SD) and silychristin (SC)], silybin is the major pharmacologically active compound. Korean Pharmaceutical Codex (2nd ed.) describes silybin as the main substance of Cardus Marianus extract as supportive treatment of chronic inflammatory liver disorders. The aim of this work was to analyze silybin from various preparations containing cardus marianus extract, nicotinamide, and riboflavin (CNR). Nine commercial products were tested using reversed-phase HPLC-PDA assay. The limits of detection and quantification were $0.2\;{mu}g/ml$ and $1\;{mu}g/ml$, respectively. Calibration curve showed a good linearity ($r^2$=1.00000) in the range of $1{\sim}500\;{\mu}g/ml$ of silybin standard solutions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.10a
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• pp.179-183
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• 2001

Vibration isolation of mechanical systems, in general is achieved through either passive or active vibration control system. Although passive vibration isolators offer simple and reliable means to protect mechanical system from vibration environment, passive vibration isolator has inherent performance limitation. Whereas, active vibration isolator provide significantly superior vibration-isolation performance. Recently, many studied and applications are carried out in this field. In this study, vibration-isolation characteristics of active vibration control system using electromagnetic force actuator are investigated. Some control algorithms. Optimal Feedforward are used for active vibration isolation. Form the experimental results of each control algorithms, active vibration isolation characteristics are investigated.

• Proceedings of the KIEE Conference
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• 2001.07e
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• pp.67-71
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• 2001

Nowdays, we can communicate using Information Technology such as internet, personal computer, mobile phone etc. To protect global environment, it is also reqired to invent products efficiently reduce energy consumption. here, I studied organic EL and inorganic EL because organic EL display is appropriate device as light, thin, energy-saying display following CRT, LCD. As a result, I realized that we are supposed to study more on invention, efficiency and mass-production of materials. Comparing with another display, however, it would be marketable in few years, considering short history of its full-scaled studies.

• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.467-472
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• 2012

In this study, water quality and acute toxicity using Daphnia magna were analyzed to investigate the eco-toxicological substances identified as statistical analysis and propose a management plan for the effluent of Banwol industrial complex, Ansan, Gyeonggi-do. Cu, Zn, F, Mn concentrations in the effluent far exceeded the US standards to protect the aquatic ecosystem and eco-toxicity values were 5 ~ 22 TU. However, concentrations of heavy metals significantly decreased after Ansan public wastewater treatment plant operating a biological treatment and toxicity values were 0 TU. Zn, Cr, F and Cu in the effluent showed very strong and strong positive correlations with eco-toxicity values, respectively. Regression analysis resulted in an equation between toxicity and Zn, TU = $4.884{\times}Zn$ (mg/L) -0.391 showing Zn concentration should be managed less than 0.285 mg/L to keep the eco-toxicity (TU) less than 1.

• Journal of Soil and Groundwater Environment
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• v.21 no.4
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• pp.20-29
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• 2016

Although a number of chemical accidents have been occurred in South Korea, the effective prevention act for soil contamination has not been established so far. To effectively protect soil contamination from chemical accidents, decision support laws and regulations are absolutely essential. Regarding this situation, this study was aimed at diagnosing problems in current chemical safety management and prevention and response system against chemical accidents through analyzing the domestic and foreign causes of chemical accidents and the accident response procedures and finally suggesting policy measures for solving those problems. In order to clarify management of soil contamination by chemical accident, this study suggests the establishment of chemical accident preparedness, response, and making of local chemical management law and policy. This law needs to be supported by a clear management framework to guide government officials and all other stakeholders in the management of soil contamination by chemical accident.

• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.121-125
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• 2022

As the technologies of the 4th industrial revolution develops, spatial information is becoming digitized. Now, even with a smartphone, we can easily identify the location of national & military critical facilities located in the mega cities. As a result, mega cities' national & military critical facilities were exposed to not only traditional threats, but also non-traditional threats such as terrorism, cyber hacking, and criminal activities. This study suggests a way to protect national & military critical facilities of mega cities from such threats. Considering limitation of time & resources, protecting perfectly all national & military critical facilities is impossible, so we should focus on their critical nodes. Specifically, We suggest ways to protect the critical nodes by converging some measures such as design & arrangement in harmony with the surrounding environment, underground construction & covering, and visual deception. Transparency of digital spatial information will further increase with the advent of urban air mobility and autonomous vehicles in the future. Therefore, in order to prepare for future threats, we should take measures to minimize the exposure of critical nodes.

• Journal of the Korea Society of Computer and Information
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• v.28 no.11
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• pp.73-80
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• 2023

In this paper, a technology to protect important information from access in order to revitalize the cloud service market. A technology is proposed to solve the risk of leakage of important confidential and personal information stored in cloud systems, which is one of the various obstacles to the cloud service market. To protect important information, access control rights to cloud resources are granted to cloud service providers and general users. The system administrator has superuser authority to maintain and manage the system. Client computing services are managed by an external cloud service provider, and information is also stored in an external system. To protect important in-house information within the company, all users, it was designed to provide access authority with users including cloud service providers, only after they are authenticated. It is expected that the confidentiality of cloud computing resources and service reliability achieved through the proposed access control technology will contribute to revitalizing the cloud service market.

• Journal of Korea Water Resources Association
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• v.56 no.5
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• pp.357-362
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• 2023

The conflict between upstream and downstream regions is a representative social conflict in Korea. It is important issues in the economic and environmental aspects related to interests of property rights and water quality conservation. however, it is insufficient for studies on the economic damage and benefits between upstream and downstream by policy. We studied validity for drinking water protect zone, one of the major water conflict in Korea, by comparison between social loss by property rights restriction in the upstream and social benefits in the downstream and we proposed integrated water management policy in basin level.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.7
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• pp.2719-2735
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• 2015

In the cloud environment, users pay more attentions to their data security since all of them are stored in the cloud server. Researchers have proposed many mutual authentication schemes for the access control of the cloud server by using the smart card to protect the sensitive data. However, few of them can resist from the smart card lost problem and provide both of the forward security and the backward security. In this paper, we propose a novel authentication scheme for cloud computing which can address these problems and also provide the anonymity for the user. The trick we use is using the password, the smart card and the public key technique to protect the processes of the user's authentication and key exchange. Under the Elliptic Curve Diffie-Hellman (ECDH) assumption, it is provably secure in the random oracle model. Compared with the existing smart card based authentication schemes in the cloud computing, the proposed scheme can provide better security degree.

• Journal of Advanced Information Technology and Convergence
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• v.10 no.2
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• pp.49-59
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• 2020

As technologies have been developing, our lives are getting easier. Today we are surrounded by the new technologies such as AI and IoT. Moreover, the word, "smart" is a very broad one because we are trying to change our daily environment into smart one by using those technologies. For example, the traditional workplaces have changed into smart offices. Since the 3rd industrial revolution, we have used the touch interface to operate the machines. In the 4th industrial revolution, however, we are trying adding the speech recognition module to the machines to operate them by giving voice commands. Today many of the things are communicated with human by voice commands. Many of them are called AI things and they do tasks which users request and do tasks more than what users request. In the 4th industrial revolution, we use smartphones all the time every day from the morning to the night. For this reason, the privacy using phone is not guaranteed sometimes. For example, the caller's voice can be heard through the phone speaker when accepting a call. So, it is needed to protect privacy on smartphone and it should work automatically according to the user context. In this aspect, this paper proposes a method to adjust the voice volume for call to protect privacy on smartphone according to the user context.