• Honam Mathematical Journal
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• v.33 no.2
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• pp.279-300
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• 2011

For a subset system M on any poset, M-Scott notions, such as M-way below relation,M-continuity,M-Scott convergence (of nets and filters respectively) and M-Scott topology are proposed Any approximating auxiliary relation on a poset can be represented by an M-way below relation such that this poset is M-continuous. It is shown that a poset is M-continuous iff the M-Scott topology is completely distributive. The topology induced by the M-Scott convergence coincides with the M-Scott topology. If the M-way below relation satisfies the property of interpolation then a poset is M-continuous if and only if the M-Scott convergence coincides with the M-Scott topological convergence. Also, M-continuity is characterized by a certain Galois connection.

• 대한공업교육학회지
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• v.30 no.2
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• pp.3-11
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• 2005

The purpose of this study is to measure the level of the key competencies of industrial high school students and to use it as the basic material so as to improve the key competencies. The subject was 359 industrial high school students(boys: 244, girls: 115) in Seoul, Daejeon, Gwangju, and Busan. The instrument used to measure the key competencies is that developed by Cheol-Young Jeong, which was partly revised with the help of a group of experts. The results of this study showed some of skills were below an average of 3.0, which were writting skill(M=2.85) and speaking skill(M=2.96) in communication skills, logical thinking(M=2.98) in problem solving skills, leadership skill(M=2.88) in interpersonal skills, and self-improvement skill(M=2.96) and the spirit of public service(M=2.93) in self-management and self-improvement skills. But technology skills were above an average of 3.0. And it appeared that technology skills(P=.023) depended on having a certificate or not, and so did communication skills(P=.020) and problem solving skills(P=.034) on the types of a course(employment or entrance into a college). So, to strengthen the key competencies which appeared below an average of 3.0 in this study, not only does the curriculum of industrial high schools need to be reorganized, but systematic strengthening program of key competencies should also be developed.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.579-584
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• 2019

The flight characteristics of 11 cinereous vultures (Aegypius monachus) were analyzed by a global positioning system (GPS) tracker(WT-300; KoEco, Inc.). The wintering period in Korea averaged 131 days (SD=17.4) and the average flight rate was 19.6%. The flight altitude was below 100 m for 21.6% of the flight, 101-200 m for 25.3%, 201-300 m for 19.0%, and below 300 m for 65.9%. There was a positive correlation (r=0.929) between the hourly flight rate and altitude. The predominant monthly flight altitude was 101-200 m (p<0.05). The wintering cinereous vultures lowered their flight rate and flew at an altitude of less than 300 m. This is thought to be an efficient way to find food through social interaction.

• Journal of Korean Vacuum Science & Technology
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• v.3 no.1
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• pp.74-78
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• 1999

For a high efficient field emission display (FED), the specific vacuum conditions below 10-7 Torr should be required. However, because the FED has the geometrical restriction due to its micro size, the thin film getters can be proposed for chemical pumping as a way to reduce impurity gases in the panel. The thin film getters, developed by employing the coating of new materials such as NI or Pt on getter surface, can be used without any activation process and show the enhanced sorption characteristics. Especially, using the Zr (1${\mu}{\textrm}{m}$) thin film getters with the Pt surface layer, the significant gettering for various active gases could be achieved from 9$\times$10-5 Torr to 1$\times$10-6 Torr or below. this good sorption properties is mainly contributed to the surface coating layer which shows the catalytic effect for gas dissociation and protects the getter materials against oxidation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.4
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• pp.1248-1253
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• 2010

In this paper, the compensation algorithm for localization using the concept of equivalent distance rate(AEDR) in order to compensate ranging error in the SDS-TWR(Symmetric Double-Sided Two-Way Ranging) is proposed and the performance of the proposed algorithm is analyzed by the localization experiments. The ranging error of the SDS-TWR in the distance between mobile node and beacon node is measured to average 1m~8m by ranging experiments. But it is confirmed that the performance of the localization by the AEDR is better than that of the SDS-TWR 4 times in university auditorium and corridor, and the localization error of above 3~10m is reduced to average 2m and that of below 3m is reduced to average 1m respectively. It is concluded that the AEDR is superior to the NLOS(Non Line Of Sight) than LOS(Line Of Sight) in performance of ranging compensation for localization, and the AEDR is more helpful to localization systems practically considering the environment of sensor networks is under NLOS.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.5
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• pp.386-393
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• 2007

This paper studies the ventilation characteristics according to the jet fan location at the long road tunnel using the CFD software 'FLUENT' which is based on the finite volume method. The tunnel model used in the analysis has a length of 1600m, a cross sectional area of $120m^3$, and is composed of 3 lanes and one way. The velocity profile, the distribution of CO concentration and the ventilation flow rate within the tunnel are analyzed, respectively. In the analysis, it is found that the dependence of the ventilation flow rate upon the jet fan location is small, but the CO concentration in the tunnel is at the lowest when the jet fans are installed near the tunnel outlet. An air stream right below the jet fan is almost inactive due to the strong stream injection near the jet fan. Thus, the pollution level below the jet fan must be higher than the other area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.914-919
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• 2010

It is confirmed that as the distance measurements accuracy of the SDS-TWR(Symmetric Double-Sided Two-Way Ranging) based on CSS(Chirp Spread Spectrum) is considerably degraded due to frequency interference and it causes to severe errors in the localization applications. In this paper, the compensation algorithm based on error rate offset of distance measurement ($CA_d$) is proposed for the purpose to reduce the ranging errors due to by the SDS-TWR ranging problems. The $CA_d$ measures the distance values between two nodes by means of 1m interval about 1~25m distances in the SDS-TWR, and compensates the distance values using the parameters related to the distance compensation. From the experiments, it is analyzed that the $CA_d$. have reduced the distance error to average 95cm and maximum 526cm, and the distance error by the $CA_d$ was below about 60cm in the 25m distances. In particular, the performance of the distance measurements accuracy by the $CA_d$ is very high in LOS(Line Of Sight) environments.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.3
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• pp.323-332
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• 1997

It was reported by some researchers that two-stage parallel-plate ESPs, commonly called electronic air cleaners, show decreasing behavior of collection efficiency as particle size decreases below about $0.03{\mu}m$. This phenomenon is attributed to partial particle charging characteristics, where some of incoming particles are not charged in the charging cell of 2-stage parallel-plate ESP. One way to improve the decreasing collection efficieny in that particle size range is to enforce particle charging quantity in the charging cell. In the present study, in order to do this a 2-wire series-type charging cell modified from a 1-wire normal-type one was suggested and investigated theoretically and experimentally concerning improvement of the collection efficiency. It was confirmed from the experimental and theoretical works that the collection efficiency was apparently improved.

• Journal of the Korean Institute of Gas
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• v.23 no.1
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• pp.41-46
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• 2019

LNG is supplying to consumers as gas phase vaporized by major seawater vaporizer, i.e.. open rack vaporizers. But as soon as the temperature of seawater drops below $5^{\circ}C$ in winter, the submerged evaporators should be operated and cause a lot of energy consumption because of their natural gas combustion. In order to reduce the consumption amount, in this study new two-way supplying method of seawater instead of the present one-way supplying system is introduced and analysed the technical possibilities and economical savings. The results showed that in case of the temperature of seawater becomes below $2.5^{\circ}C$, LNG can be evaporated using ORV without operating S MV. If this system is applied in Incheon LNG terminal, the energy saving reaches 11,770 Ton of LNG as 11,760 million won. By the analysis, the two-way supplying system of seawater in ORV can be the most effective method to be able to save huge amount of energy every year.

• Journal of the Korean Society of School Health
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• v.9 no.2
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• pp.161-170
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• 1996

This research was performed to screen eye health status for pre-school children (4~5 age) and establish as eye health checking system m community health center. This data was collected from 1st February, 1995 to 31st October, 1995. To screen the state of their vision, the Developed Visuual Test (D.V.T) was used for pre-school children. This is used at home by their parents and then it is also used among the kindergarten health team at Jung-gu health center in Seoul. This was done with the and of Randot and Han Choun Souk tests. The total number of children who were tested was 1441. Among the children, children aged 5 were 707, and those aged 4 were 734. The results of this study were as follows; * Description of the health status for the pre-school children. 1. The rate of children average vision in both eyes, whose was below 05 by Han Choun Souk are 7.6% (age 4) and 4.8% (age 5). 2. Only 20 4% (age 5) and 30 8% (age 4) of the pre-school children had been tested through the ophthalmic department. 3. The children with a level below 05 (Han Choun Souk test) had been tested only 43% (age 4), and 12% (age 5) 4. There was no particular difficulty in understanding the D.Y.T: 13.9% (age 4), 11.6% (age 5) of the tested children had eye problems. 5. 231 cases were trichiasis, entropin, strabismus, and amblyopia. * The different visual tests. The results of the visual tests between the two groups (parents and health teams) are similar and it shows that parents can easily test at home. * Delivery system of the D.V.T questionnaire The way children's parents received the D.V.T questionnaire were carried out by two ways By mall from the community health center. Send through the institution, for example the kindergarten school The receipt rate of this D.V.T questionnaire sent through the institution was higher than sent by mall.