• Journal of Forest and Environmental Science
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• v.17 no.1
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• pp.29-36
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• 2001

Compared to other industries, pulp and paper industry use a lot of water. As a result, a large amount of the waste water is discharged in the pulp and paper industry. This study was investigated to prevent the environmental pollution terribly faced with our society nowadays. In the waste water of pulp and paper, there are so many things in the waste water, like fiber, filler, and other organic solvent etc. so we must remove them from our environment. This study was investigated to experiment on test of impressed filtration with the kind and quantity of coagulant and the variance of pressure. In this study, we used feds, alums. $CaCl_2$, polymer as a coagulant and these pressure was 49, 98, 147, 196kpa. According to this study, we measured the speed of filtration and turbidity, measuring filtrated water. According to the values, we know the fact that as the consistency of coagulant and pressure were high, the filtration was good.

• Journal of Digital Contents Society
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• v.16 no.2
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• pp.307-316
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• 2015

Although the use of CAD and CAM technologies has been broadly adopted by architecture-engineering- construction-facility management (AEC/FM) industry as the means of producing complex forms, there are still remained issues such as reducing cost, and enhancing quality and manufacturability. In this paper, to resolve given issues, we suggest a process of rationalization in digital architecture design and fabrication as an integrated approach. The rationalization, which is usually used as the term related with the skin panel of free-form architecture, is a process of re-designing a digital model to meet the requirements of manufacturing considering the gap with an original designs. Thus we classified this process and conducted a case study of fabricated models as an exploratory study. As the result, we found that each phase is connected with other phases with the circulation of information and rationalization process can be determined as the circulative process which re-designs digital model by minimally deviating from the original design based on the information deducted from analysis of inter-compatability of software and requirement of hardware.

• Journal of The Korean Association For Science Education
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• v.23 no.2
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• pp.190-199
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• 2003

The purposes of this study was to investigate the effect of inductive Instructional method and deductive one concerning the learners' population genetic concepts and achievement according to learners' cognitive characteristics. For the study, 180 students were sampled from a boys' high school: 90 students for inductive teaching method and 90 students for deductive teaching method. Group Assessment of Logical Thinking(GALT) and Group Embedded Figure Test (GEFT) were used as the measure of cognitive characteristics. The results of this study were as follows. 1) The inductive instructional method was more effective in the understanding of population genetic concepts and their achievement. 2) Inductive instructional method was more effective than deductive one for the learners in formal operational level and in field independent cognitive style. 3) For the learners in a transitional level and field dependent cognitive style, deductive instructional way was more effective than inductive way on the average, but it was not statistically significant. It was turned out that learners' cognitive level was one of important factors when teachers instruct the concept of population genetics.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.423-430
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• 2004

This study intended to understand movements of turbid water in selective with drawal reservoirs before and after summer monsoon. Mean rainfall during November-May was low, compared to that during June-October. The reservoir water was discharged through watergates when previous rainfall and inflow exceeded 50 mm and $80\;m^3s^{-1}$, respectively. Intake towers were generally used except for the period of the high runoff. Average turbidity in gown-reservoir showed a difference of 29.9 NTU between premonsoon and postmonsoon. Diameter of particles of turbid water ranged between 0.435 and $482.9\;{\mu}m$. Fine particles such as clay were much denser than the larger particle. In the whole stations, clay component was relatively higher with a proportion of that in the particle distribution. Particle composition of turbid water showed that clay consisted of 94.4-98.9% and silt made of 1.1-5.6%. Analysis on turbid water movements derived from particle distribution showed a linear increase from the deep layer toward the surface layer in lower area of a reservoir. This was closely related with the hydraulic behavior of the reservoir, and heavily affected by the discharges through selective withdrawal towers and watergates. Turbid water originated from stream sediments in the middle area then resuspended in the down-reservoir causing a movement between the surface and middle layers of the reservoir. Therefore, such phenomenon needs to be understood for reservoir water quality management.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.266-273
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• 2009

This study was conducted to develop more convenient simultaneous determination method by matrix solid phase dispersion (MSPD) and HPLC for sulfonamides such as sulfamerazine (SMR), sulfamethazine (SMT), sulfamonomethoxine (SMM), sulfadimethoxine (SDM), sulfaquinoxaline (SQX), and tetracyclines including oxytetracycline (OTC), tetracycline (TC) chlortetracycline (CTC) in prok and flatfish. The limits of detection were 0.047 $mg{\cdot}kg^{-1}$ for OTC, TC, SMR, SMT and SMM, and 0.033 $mg{\cdot}kg^{-1}$ for CTC, SDM, and SQX, respectively. So it is sufficiently possible to detect the eight tetracyclines and sulfonamides under their MRLs ($0.1{\sim}0.2mg{\cdot}kg^{-1}$). The average percentage recoveries of sulfonamides and tetracyclines from pig muscle and flatfish spiked standard solution were approximately $80.25{\sim}101.25%$ and $85.77{\sim}121.42%$, respectively. Therefore this method was efficient for simultaneous analysis of eight tetracyclines and sulfonamides.

• Journal of the Korean Society of Radiology
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• v.11 no.2
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• pp.117-122
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• 2017

The purpose of this study is to prevent infection in the hospital by computed radiography portable and to provide basic data on infection-related education by investigating bacterial contamination level of computed radiography portable equipment using IP cassette. The results suggest that IP cassette No. 1 is infected with CNS and VRE, no. 2 with CNS, No. 3 with CNS and Pseudomonas aeruginosa, No. 4 with CNS, No. 5 with CNS and Bacillus sp., and No. 6 with enterococcus faecium. Enterococcus faecium and bacillus sp. were detected from the IP reader and Acinetobacter baumannii was detected on the mobile handle; Bacillus sp. on the control buttons, CNS and Bacillus sp. from the irradiation control handle, Acinetobacter baumannii on the x-ray generation switch, and CNS on the barcode scanner. In addition, Bacillus sp. Acinetobacter baumannii was found on the IP cassette mobile table and CNS and bacillus sp. were found on the lead apron. Acinetobacter baumannii and CNS were detected from the medical gloves worn by a radiological technologist during radiography. This suggests that IP cassette should be sterilized after use as it can hand over bacteria to IP reader and IP mobile table. Medical gloves that are in direct contact with patients should also be replaced after using them once and other supplies such as x-ray generation switch and lead apron should thoroughly be sterilized to prevent infection due to radiography as they are in a lot of contact with patients.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.5
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• pp.919-929
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• 2013

Recently, a variety of IT technologies are applied to the vehicle. However, some vehicle-IT technologies without security considerations may cause security problems. Specially, some researches about a smart key system applied to automobiles for authentication show that the system is insecure from replay attacks and modification attacks using a wireless signal of the smart key. Thus, in this paper, we propose an authentication method for the driver by using driving patterns. Nowadays, we can obtain driving patterns using the In-vehicle network data. In our authentication model, we make driving ppatterns of car owner using standard normal distribution and apply these patterns to driver authentication. To validate our model, we perform an k-fold cross validation test using In-vehicle network data and obtain the result(true positive rate 0.7/false positive rate is 0.35). Considering to our result, it turns out that our model is more secure than existing 'what you have' authentication models such as the smart key if the authentication result is sent to the car owner through mobile networks.

• Journal of Korea Game Society
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• v.9 no.6
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• pp.45-56
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• 2009

This Study has limited our scope to the study of satisfaction factor. Due to the extensiveness of fun factors of games. We had identified satisfaction factors through investigating various theories based on funology. Then, we have directly applied the satisfaction factors to games in order to define the satisfaction factors of online FPS game. Then, we have applied the satisfaction factors on to four online games, at the first phase of the study. We interviewed a group of online FPS game experts to identify the constituent elements of the factors and concluded the second phase of our investigation based on the results from the first and second phases, we have conducted a survey to verify the hypothesis. We have verified the reciprocal relationship between the satisfaction factors and game popularity by conducting a multiple regression analysis on the survey results. To conclude, there is a correlation between online FPS games and the satisfaction factors; the satisfaction factors cause the users to be absorbed into the game and to enjoy it for a long period of time.

• Korean Journal of Cognitive Science
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• v.13 no.2
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• pp.1-13
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• 2002

This Paper is concerned with the impact of linguistic markers of coherence, such as causal connectives. repetitions. and anchoring devices. on the comprehension of a scientific text in Korean. A scientific text on the process of lightning formation was selected. and two versions of the text were constructed by varying the strength of coherence. Eighty-two undergraduate students took Part in the experiment in which they were instructed to fill in the blanks in each text in a recall and a recognition task and to respond to a set of question in a comprehension test. The results of this experiment revealed a selective effect of the cohesive markers. It was found that the different linguistic signals seem to Play a facilitating role in varying degrees in accordance with the type of tasks involved Moreover an analysis of topic continuity from the beginning paragraphs through the last revealed that the text was better understood in the paragraphs containing the main topic better than those without it. This finding seems to indicate that the off-line processing of scientific text is not influenced solely by the local bottom-up processing alone The effect of topic continuity seems to suggest that a global. top-down processing effect has an important role to play. overriding the impact of cohesive devices.

• Journal of Internet Computing and Services
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• v.12 no.2
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• pp.85-101
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• 2011

The recommender system analyzes users' preference and predicts the users' preference to items in order to recommend various items such as book, movie and music for the users. The collaborative filtering method is used most widely in the recommender system. The method uses rating information of similar users when recommending items for the target users. Performance of the collaborative filtering-based recommendation is lowered when attacker maliciously manipulates the rating information on items. This kind of malicious act on a recommender system is called 'Recommendation Attack'. When the evaluation data that are in continuous change are analyzed in the perspective of data stream, it is possible to predict attack on the recommender system. In this paper, we will suggest the method to detect attack on the recommender system by using the stream trend of the item evaluation in the collaborative filtering-based recommender system. Since the information on item evaluation included in the evaluation data tends to change frequently according to passage of time, the measurement of changes in item evaluation in a fixed period of time can enable detection of attack on the recommender system. The method suggested in this paper is to compare the evaluation stream that is entered continuously with the normal stream trend in the test cycle for attack detection with a view to detecting the abnormal stream trend. The proposed method can enhance operability of the recommender system and re-usability of the evaluation data. The effectiveness of the method was verified in various experiments.