• Korean Journal of Construction Engineering and Management
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• v.14 no.1
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• pp.124-132
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• 2013

An influx of the population to the city has soared due to industrialization. As times go by, cities become densely populated so Korean government started to construct a number of buildings including apartment housings. Because they have become functionally, structurally, esthetically deteriorated over the past two decades. some improvements are needed. There are mainly two ways to improve old buildings: remodeling and reconstruction. Between the two, the first one is more popular as it is less time-consuming and more eco-friendly. Demolition work comes first for both of them and it should not give negative effects since it is regarded as a CP(Critical path) in the overall process. For this reason, a thorough construction management must be done. The reality, however, demolition is managed by the construction manager's experiences and decisions. If the key factor of demolition which is the planning of manpower and machine equipment, is determined by unscientific and subjective judgments, its period and risk also will increase. In particular, eco-friendly demolition can be more risky because it's been rarely conducted. Therefore, scientific and objective ways of demolition management are needed. In this context, this paper aims at analyzing productivity in each process of demolition focusing on manpower and machinery equipment which are the main parts of demolition assuming that the demands of eco-friendly remodeling demolition projects will be increasing. At the same time, by estimating working period through the output, this paper would be helpful to set up the plans for overall project in earlier stage.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.383-393
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• 2015

This study analyzed the 6th grade elementary science textbook 'Science stories' reading process of students by utilizing eye movement tracking techniques. Participants read 3 articles in the new experimental science textbooks and solved 9 problems about each article. By understanding and academic achievement results, participants were divided into high-groups, middle-groups, and low-groups. The results of eye movement characteristics of the high-groups and low-groups had the following differences. Number of fixations and number of regressions were higher in high-groups. Average fixation duration and average regressive fixation duration were longer in low-groups. Fixation time for the key sentence of the article was longer in high-groups. Analysis of a scan path and post-interview, high-groups had frequent regression between sentences and they knew where the core of the article is and paid much attention there. In contrast low-groups are sequentially read most articles and some of them had a leap of abnormal range. Problem-solving approach is also different between groups. In conclusion reading style is associated with the science stories comprehension and students who had more regressions, much core search process, effective attention distribution, high concentration showed better understanding results. Also words or sentences used in textbooks are associated with science stories comprehension.

• Journal of Families and Better Life
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• v.9 no.2
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• pp.1-18
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• 1991

The purpose of this study is to find out influential variables related to Home Management Ability of urban home makers. This study focuses on the following aspects; 1) to find out which variables of sociodemographic variables (ie. home maker's age, level of education-husband, wife, job-husband, wife, income, duration of marriage), of psychological variables (ie. degree of resourcefulness recognition, degree of stress recognition, degree of life level recognition) have significant effects on home management ability. 2) to find out which variables of sociodemographic variables have significant effects on degree of resourcefulness recognition, of stress recognition, and of life level recognition. 3) to identify the influence of significant variables related to home management ability. Data was analyzed by frequency. percentage, mean , F-test, t-test, Duncan's multiple range test. regression analysis , path analysis pearson's r. x2-test. Major findings are as follows; 1) The level of education (husband , wife)and occupation of husband were variables to have influences on home management ability. 2) a. The level of education (husband, wife) and income were variable to have influences on degree of resourcefulness recognition. b. The employment of home makers. income, and the form of family were variables to have influences on degree of stress recognition. c. The level of education (husband, wife) occupation of husband , income , and duration of marriage were variables to have influences on degree of life level recognition. 3) There were significant relationships between home management ability and degree of resourcefulness recognition and of stress recognition (r=0.13, r=-0.12, p<.05). a. The higher degree of resourcefulness recognition, the higher home management ability (x2=11.17. df=4. p<.05) b. The higher degree of stress recognition, the lower home n=management ability (x2=14.64. df=4. p<.01) 4) The education level of homemakers (β =0.15) and income (β=0.12) were variables to have indirect influences on home management ability through the medium of the degree of resourcefulness recognition (β =0.13) 5) The employment of home makers (β=-0.17) was a variable to have indirect influence on home management ability through the medium of the degree of stress recognition(β=-0.12) 6) the education level of husband (β=0.16) and income (β=0.32) were variables to have direct influence on degree of life level recognition. 7) The degree of life level recognition (β=0.13) and education level of home makers (β=0.17) were variables to have indirect influences on home management ability through the medium of the degree of resourcefulness recognition (β=0.13) 8)The degree of life level recognition (β=-0.22) the employment of home makers(β=-0.17) and the from of family(β=-0.10) were variables to have indirect influences on home management ability through the medium of the degree of stress recognition.

• Journal of The Korean Association For Science Education
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• v.33 no.7
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• pp.1471-1485
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• 2013

The purpose of this study was to develop a HAM (Heuristic Attention Model) by analyzing the difference between eye movements according to the science achievement of elementary school students on discrimination task. Science achievement was graded by the results of the Korea national achievement test conducted in 2012 for a random sampling of classes. As an assessment tool to check discrimination task, two discrimination measure problems from TSPS (Test of Science Process Skill, developed in 1994) which were suitable for an eye tracking system were adopted. The subjects of this study were 20 students from the sixth grade who agreed to participate in the research. SMI was used to collect EMD (eye movement data). Experiment 3.2 and BeGaze 3.2 programs were used to plan experiments and analyze EMD. As a result, eye movements of participants in discrimination tasks varied greatly in counts and duration of fixation, first fixation duration, and dwell time, according to students' science achievement and difficulty of the problems. By the analysis of EMD, strategies of the students' problem-solving could be found. During problem solving, subjects' eye movements were affected by visual attention; bottom-up attention, top-down attention and convert attention, and aflunter attention. In conclusion, HAM was developed, and it is believed to help in the development of a science learning program for underachievers.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.254-260
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• 1999

Meteor Burst Communication can provide effective and economical means of communication where long distance VHF NLOS data transmission is needed; often ranges more than 1000 km. It has been, however, so far considered unsuitable for short distance application because of phenomenal decrease in burst durations, which leads to decreation of total duty rate of the system. This paper extensively analyzes characteristics of shot distance MB(Meteor Burst) path and shows the low duty rate may be improved by increasing burst rate through adapting antenna beam width to cover entire hot-spot region in the space and, by compensating effective burst length through cutting down man-made noises introduced by antenna. Based on the analysis, we are developed a small-opening-cavity antenna, especially designed for short distance MB path. In operation, the antenna is to be buried under ground surface so as to improve directivity and reduces noise introduction. The antenna exhibits power gain of 3 dB with 90 degree beam width and thus enables to illuminate entire hot-spot regions with the elevation angle of 8-90 degree which is the case of transmission less than 100 km. Directivity horizontal to earth surface is suppressed to minimum which enables to cut man-made noises from near-by sources down to more than 3 dB from the level reported with conventional 4 element Yagi. A series of experiments performed on 100 km MB paths have conformed that, with the antenna installed at receiving site, the burst rate and duration time have been noticed to increase by 10 and 20 percent respectively from the values obtained by conventional 4-element Yagi antenna under same testing condition.

• Korean Journal of Optics and Photonics
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• v.18 no.1
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• pp.66-73
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• 2007

The various output characteristics of a pulsed Ti:sapphire laser oscillator with a plane-parallel resonator, pumped longitudinally by the second harmonic wave of a Nd:YAG laser, and the output of a Ti:sapphire laser amplifier operated along the single path of the oscillator beam were investigated and analyzed. In the case of the oscillator, we measured the spectrum, the pulse buildup time, the temporal duration time of the pulse, and the output energy according to the variation of the pumping energy, resonator length, and the reflectance of the output coupler. And, in the case of the amplifier, we investigated and analyzed the output energy of the amplifier as a function of the time difference between the two pump beams of the oscillator and the amplifier, the pumping energy of the oscillator, and the pumping energy of the amplifier When pump energies of both the oscillator and the amplifier were 18 mJ/pulse, we could find that the output energy of the amplifier increased linearly and gradually up to the time difference of 35 ns. Finally, we determined that the slope efficiencies of the oscillator and the amplifier were 23.5 % and 11.6 %, respectively.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.291-298
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• 2015

It is pretty hard to sell the kids' furniture online because of the characteristics of the consumers that they will like to make purchases after looking at the actual objects and then considering purchasing them. In this paper, we made the scheme to boost the on-line malls of the kids' furniture market by collecting the consumers' intention to buy before purchasing with questionnaire survey, comparing it with the real data of purchasing, and analyzing the differences. We analyzed the visit number of shopping mall, the page number of views, page duration time per visit, and customer's shopping path by using log data from the children's furniture online shopping mall server. In addition, we analyzed where the customer's influx route is among online advertising. We found that there are requirements for the designs, prices, brand names, and practicalities by the consumers purchasing the kids' furniture online. To strengthen competitiveness of the online kids' furniture malls, we proposed that reinforcing the on-line experiences of furniture, the differential strategies for the products, ensuring the fixed customers are needed.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.192-195
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• 2004

Products of gridded surface wind and windstress vectors over the world ocean have been constructed by satellite scatterometer data with highly temporal and spatial resolutions. Even if the ADEOS-II/SeaWinds has supplied surface wind data only for short duration in Apr. to Oct. 2003 to us, it permits us to construct a product with higher resolution together with the Qscat/SeaWinds. In addition to our basic product with its resolution of $1^{\circ}\times1^{\circ}$ in space and daily in time, we try to construct products with $1/2^{\circ}\times1/2^{\circ}$ and semi- and quarter-daily resolution. These products are validated by inter-comparison with in-situ data (TAO and NDBC buoys), and also compared with numerical weather prediction(NWP) ones (NCEP reanalysis). Result reveals that our product has higher reliability in the study area than the NCEP's. For the open ocean regions in the middle and high latitudes where there are no in-situ data, we find that there are clear differences between them. Especially in the southern westerly region of 400-600S, the' wind-stress magnitudes by the NCEP are significantly larger than the others, suggesting that they are overestimated. We also calculate wind-stress curl field that is an important factor for ocean dynamics and focus its spatial character in the northwestern Pacific around Japan. Positive curl areas are found to cover from southwest to northeast in our focus region and almost correspond to the Kuroshio path. It is suggested that the vorticity field in the lower atmosphere is related to the upper oceanic one, and thus an aspect of air-sea interaction process.

• Journal of Korean Academy of Nursing
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• v.31 no.2
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• pp.244-256
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• 2001

The purpose of this study was to investigate the effects of coping mechanisms on uncertainty and depression. The subjects were 71 cancer patients selected from Junbook National University Hospital, and the data collection period was from June 21 to October 19 of 2000. Uncertainty was measured by using Mishel's Uncertainty Scale, problem- focused coping, and emotional-focused coping. The data was collected by a questionnaire developed by Lee (1984), and then depression measured by using Beck's depression scale. program by Pearson Correlation Coefficients, and Path analysis. The results were as follows : 1. The mean uncertainty score was 59.17, the mean problem-focused coping score was 48.78, the mean emotional-focused coping score was 42.52. 2. The mean depression score was 15.77. 3. Uncertainty in illness was significantly related to depression (p=0.003) and emotional-focused coping (p=0.028), but uncertainty was not associated with coping mechanisms. 4. When analyzed multiple regression between uncertainty, problem-focused coping, emotional- focused coping, and depression, more specifically emotional-focused coping showed a stronger association with depression than problem-focused coping. 5. Depression was highly correlated with economic status (p=0.015), educational background (p=0.005), duration of disease (p=0.045). 6. Problem-focused coping and emotional-focused coping appeared to function as moderators instead mediators on the relation between uncertainty and depression. In addition, as a whole, uncertainty showed a significant moderating effect on depression, while problem-focused coping did on depression. Finally, limitation of present findings were discussed and implications for future studies are suggested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.4
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• pp.1976-1981
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• 2013

In this paper, we propose a frequency-domain interference cancellation algorithm for direct-sequence spread spectrum systems. In the previously proposed frequency-domain interference cancellation algorithms that protocol defines the rules concerning the collection of means of Transmission Control Protocol (TCP: Transmission Control Protocol) is the most widely used in the transport layer. Two-way traffic through the network path to the same end-to-end transfer of data in the opposite direction between pairs of nodes are infused with two or more TCP connection using the network traffic patterns from the exchanger and routers share results of approval. Per-flow input/output structure of matter using the LTS online reaction when evaluated as this is the most important factor. TCP-MT when the connection duration is one of the largest performance gains.