• Bulletin of the Korean Chemical Society
• /
• v.19 no.12
• /
• pp.1334-1336
• /
• 1998

Kinetic studies are carried out on the reactions of 2-chloro-2-propen-1-yl arenesulfonates with anilines and N,N-dimethylanilines in acetonitrilile at 45.0 ℃. The 2-chloro substituent is found to deactive the allyl moiety with considerable decrease in the rates. The sign and magnitude of the cross-interaction constant (ρxz 0.3) and the inverse secondary kinetic isotope effect (kH/kD 0.92) support an SN2 mechanism with a relatively tight transition state. The possibility of an SN2' mechanism can be safely precluded based on the ρxz values observed.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2017.10a
• /
• pp.57-58
• /
• 2017

New approach to achieve the safety goals in transportation and dry storage of SNF, so called SSEM has been proposed. The main concept of the SSEM is that it simplifies the reviewing processes of each campaign of the transportation or storage of SNF with standard format. This SSEM could be considered as a model case for assuring public that the SNF be managed safely.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1997.11a
• /
• pp.244-251
• /
• 1997

Since 1970s, The Petrochemical Industry in Korea has grown rapidly by the successful economic growth. While the process became larger and more complex, hazardous chemicals have been used in large quantity, Therefore, the risk of a major accident such as fire, explosion and toxic material release has been increased. Korea has been ranked the fifth in petrochemical product capacity worldwide, also required to meet international standards on process safety management. Fire Protection System integral part of safely management in Petrochemical Plants, will be reviewed.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.11a
• /
• pp.225-226
• /
• 2022

In order to secure the practicality of services using drones, improve on-site operability, and improve the convenience of aircraft maintenance, it is necessary to develop a drone station that can be safely stored while ensuring charging performance. Therefore, a total seven points of improvement were derived through laboratory experiments after the development of the first prototype, and an improved second prototype will be developed in the future based on the preceding processes.

• Journal of Electrical Engineering and Technology
• /
• v.1 no.3
• /
• pp.359-365
• /
• 2006

Since the start of the KSTAR (Korea Superconducting Tokamak Advanced Research) project, Instrumentation and Control (I&C) of the Neutral Beam Test Facility (NB-TF) has been striving to answer diverse requests arising from various facets during the project's development and construction phases. Hard-wired electrical circuits have been designed, tested, fabricated, and finally installed to the relevant parts of the system. In relation to the vacuum system I&C, controlling functions for the rotary pumps, a Roots pump, two turbomolecular pumps, and four cryosorption pumps have been constructed. I&C for the ion source operation are the temperature and flow rate signal monitoring, Langmuir probe signal measurements, gradient grid current measurements, and arc detector circuit. For the huge power system to be monitored or safely operated, many temperature measurement functions have also been implemented for the beam line components like the neutralizer, bending magnet, ion dump, and calorimeter. Nearly all of the control and probe signals between the NB test stand and the control room were made to be transmitted through the optical cables. Failures of coolant flow or beam line vacuum pressure were made to be safely blocked from influencing the system by an appropriate interlock circuit that will shut down the extraction voltage application to the system or prevent damages to the vacuum components. Preliminary estimation of the beam power through the calorimetric measurement shows that 87.9% of the total power of the 60kV/18A beam with 200 seconds duration is absorbed by the calorimeter surface. Most of these I&C results would be highly appropriate for the construction of the main NBI facility for the KSTAR national fusion research project.

• Journal of Korean Biological Nursing Science
• /
• v.13 no.1
• /
• pp.72-80
• /
• 2011

Purpose: The purposes of this study were to reveal the nutritional status and symptoms related to dysphagia and to identify the information needs of the patient with post-stroke dysphagia for self care. Methods: Fifty one subjects were selected among patients being admitted from 3 tertiary hospitals. Data were collected using questionnaires, interview, and medical record. Data analysis was done using descriptive statistics with SPSS. Results: 1) The mean hemoglobin, serum albumin, and hematocrit level of the subjects were $11.2{\pm}1.8g/dL$, $3.2{\pm}0.6g/dL$, and $33.5{\pm}2.3%$, respectively. 2) The most common symptom due to dysphagia was 'slurred speech (86.3%)', followed by 'less flexible in tongue and mouth movement (80.4%)', 'difficulty chewing and swallowing (74.5%)'. 3) The highest score of information needs for patients/caregivers was to know which foods are suitable for dysphagic patients or not ($2.67{\pm}0.48$ of 3.0 score). They also want to know how to swallow safely ($2.65{\pm}0.59$), to administer medication safely ($2.63{\pm}0.59$), and to learn rehabilitative techniques ($2.61{\pm}0.57$). Conclusion: These findings would be useful information for staffs to do multidisciplinary approach and they would be necessary for stroke patients to manage their symptoms.

• Journal of the Korea Convergence Society
• /
• v.9 no.4
• /
• pp.9-14
• /
• 2018

Recently, as the internet speed is getting faster, in the cloud environment, the service receiving device is changing from a general PC to a compact device such as a mobile phone or a tablet PC. Since handheld devices such as mobile phones or tablet PCs are often used in wireless rather than wired, there are many problems that personal information may be exposed maliciously from a third party. In this paper, we propose a user privacy protection scheme through a duplicate duplicate key generation process which can safely protect user 's privacy from third party among cloud services being served through various wireless media. The proposed scheme is used to synchronize the duplicated key between the server and the intermediary device, and aims at shortening the time of the authentication process protecting the user 's privacy. In this case, the proposed scheme uses Interleave() function and random number to synchronize the server and the intermediary device, so it can safely prevent the malicious attack of the third party.

• Journal of Korean Neurosurgical Society
• /
• v.44 no.2
• /
• pp.78-83
• /
• 2008

Objective : To understand the anatomic characteristics of the aortic arch (AA) and its major branches to build a foundation toward performing endovascular surgery safely. Methods : A total of 25 formalin fixed Korean adult cadavers were used. The authors investigated : anatomical variations of the AA and its major branches; curvature of the AA; distance from the mid-vertebrae line to the origin of the major branches; distances from the origin of the major branches of AA to the origin of its distal branches; and the angle of the three major branches, the brachiocephalic trunk (BCT), the left common carotid artery (LCCA) and the left subclavian artery (LSCA) arising from AA. Results : The three major branches directly originated from AA in 21 (84%) of the cadavers. In two (8%) of remaining four cadavers. orifice of LCCA was slightly above the stem of BCT. In remaining two (8%) cadavers, the left vertebral artery (LVA) was directly originated from AA. Average angle of AA curvature to the coronal plane was 62.2 degrees. BCT originated 0.92 mm on the right of the mid-vertebrae line. LCCA and LSCA originated from 12.3 mm and 22.8 mm on the left of the mid-vertebrae line. Mean distance from the origin of the BCT to the origin of the RCCA was 32.5 mm. Mean distance from the origin of the LSCA to the origin of the LVA was 33.8 mm. Average angles at which the major branches arise from the AA were 65.3, 46.9 and 63.8 degrees. Conclusion : This study may provides a basic anatomical information to catheterize AA and its branches for safely performing endovascular surgery.

• The KIPS Transactions:PartC
• /
• v.18C no.2
• /
• pp.71-78
• /
• 2011

Financial accidents such as password exposure of credit cards or bankbooks occur often when a password is inputted to ATM/CD(Automated Teller Machines and Cash Dispenser), so particular attention is required when inputting a password. This study suggested a method to input a password safely to prevent stealing a glance at a password in case of the use of ATM/CD. The method is that users input a password when numbers are randomly displayed and disappear not to notice the password even though someone is next to or behind the users. As methods to input a password safely, the study verified safety by dividing the methods into a test of shoulder surfing, an intuitive perspective, and a theoretical analysis. In addition, the result of implementation to apply the method to ATM/CD shows that a percentage of acquiring a password from the attack of shoulder surfing is found to be lower than an existing method, so password exposure can be prevented.

• International Journal of Highway Engineering
• /
• v.18 no.5
• /
• pp.105-115
• /
• 2016

PURPOSES : This study was initiated to analyze the characteristics of bus traffic accidents, by bus types, using the decision tree in order to establish customized safety alternatives by bus types, including the intra-city bus, rural area bus, and inter-city bus. METHODS : In this study, the major elements involved in bus traffic accidents were identified using decision trees and CHAID algorithm. The decision tree was used to identify the characteristics of major elements influencing bus traffic accidents. In addition, the CHAID algorithm was applied to branch the decision trees. RESULTS : The number of casualties and severe injuries are high in bus accidents involving pedestrians, bicycles, motorcycles, etc. In the case of light injury caused by bus accidents, different results are found. In the case of intra-city bus accidents, the probability of light injury is of 77.2% when boarding a non-owned car and breaching of duty to drive safely are involved. In the case of rural area bus accidents, the elements showing the highest probability of light injury are boarding an owned car, vehicle-to-vehicle accidents, and breaching of duty to drive safely. In the case of intra-city bus accidents, boarding owned car, streets, and vehicle-to-vehicle accidents work as the critical elements. CONCLUSIONS : In this study, the bus accident data were categorized by bus types, and then the influential elements were identified using decision trees. As a result, the characteristics of bus accidents were found to be different depending on bus types. The findings in this study are expected to be utilized in establishing effective alternatives to reduce bus accidents.