• Ocean and Polar Research
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• v.30 no.4
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• pp.475-484
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• 2008

The word 'Saemangeum' indicates an estuarine tidal flat in the southwestern part of the Korean peninsula. The Saemangeum Reclamation Project was launched as a national project in 1991 to reclaim a large coastal area of $401\;km^2$ by constructing a 33-km long dyke. The final dyke enclosure in April 2006 has transformed the tidal flat into lake and land. An integrated oceanographic study has been conducted since 2002 as a part of the Government Action Plan to monitor and assess changes in the marine environment. Prior to the dyke enclosure, the coastal environment in the Saemangeum was a complex system governed by tidal motion, estuarine processes, and coastal circulation of the Yellow Sea. The dyke construction has radically changed not only the estuarine tidal system inside the dyke, but also the coastal marine environment outside the dyke. Post to the dyke enclosure, subsequent changes such as red tide, hypoxia, and coastal erosion/deposition occur successively. Red tides appear almost the year round in the inner area. Even under the condition that the sluice gates are fully open, the water quality does not improve as much as the developers would expect, mainly due to the critical reduction of the hydrodynamic stirring power. We will introduce details of our monitoring program and significant changes in the Saemangeum marine environment, based on observations and model results.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.173.1-173.1
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• 2011

The high fuel flexibility of gas turbine power system has boosted their use in a wide variety of applications. Recently, the demand for biogas generated from the digestion of organic wastes and sewage waste water as a fuel for gas turbines has increased. We investigated the performance of high pressure biogas compression system and operating conditions for supplying biogas. The total flow per minute of biogas from food waste water digestion tank is $54Nm^3$. The main type of biogas compression system is the reciprocating system and screw type system. The target of biogas mechanical data is the as belows; inlet pressure 0.045bar, supplying biogas temperature is $30{\sim}60^{\circ}C$, and final pressure is above the 25 bar. Also, inlet conditions of biogas consist of CH4 48.5%~83%, $H_2S$ Max. 500ppm, $NH_3$ Max. 1,500ppm and Siloxane 2.7~4.6ppm. The boosting Blower system raises a pressure from 0.045bar to 1bar before main compressor. The main system lay out of reciprocating consisits of compressor driver, filter, cooling system, blowdown vessel, control system and ESD(Emergency Shut Down) system. And an enclosure package needs to be installed for reducing noise up to 75dB. The system driver is the electronic motor of explosion proof type. Forthe compressor system reliable operation, the cleaning system something like particulate filter needs to be set up in the inlet of compressor and Coalescing Filter in the outlet of compressor. Particulate Filter has to be removed above $10{\mu}m$ size of the particles in biogas. The coalescing filter(Micofine Borosilicate Glass Fibers Filter treated phenol acid) also removes moisture and oil of above $0.3{\mu}m$ to be involved in high pressure biogas up to 90%~98%.

• Journal of Korean Library and Information Science Society
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• v.47 no.1
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• pp.175-198
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• 2016

This study intends to implement a OPAC prototype for digital kids. To the end, this study applies prototyping techniques that design, evaluate and improve an early sample model. Included in this study are as follows: (1) design a conceptual model of new OPACs based on the information need analysis of digital kids, (2) implement a OPAC prototype with WordPress 4.2 version, (3) evaluate the prototype OPAC from the viewpoint of digital kids and children librarians, and finally, (4) suggest the improved model and implementational strategies for kid's OPAC. 6 fourth and fifth graders in the elementary school and 5 children librarians in public libraries participate in the final evaluation process.

• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.4
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• pp.1-18
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• 2012

With the enormous growth and various applications of private brands, national brand manufacturers are confronted with a dilemmatic situation. That is, paradoxically, some manufacturers have come to produce private brands of retailers which are potential competitors to their own brands. This study reveals why manufacturers with their own brands let themselves do the consignment production of retailers' private brands although those private brands may become strong competitors of their own brands and then investigates the condition in which manufacturers may benefit from such consignment production. Through an analysis of a game theoretical model assuming a monopoly market, the present study presents the theoretical backgrounds and provides new insights about consignment production of manufacturer with its own brand for retailer's private brand. First, such consignment production can play a role in mitigating the loss in the consignee manufacturer's own brand sales caused by the private brand in the competitive environment. Second, the effectiveness of such role is affected by the quality of the private brand produced under consignment. In other word, only if the consignee manufacturer keeps the quality of the private brand low, the manufacturer can maintain the benefit from its own brand. In addition, a consigner retailer needs to consider the final objective of launching its private brand, when it chooses its consignee manufacturer of the brand. Finally, a manufacturer with its own brand may consider consignment production as not merely an unavoidable option compelled by a retailer's power but a reasonable strategic choice to reduce the risk from competition.

• The Journal of the Acoustical Society of Korea
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• v.11 no.3
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• pp.5-13
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• 1992

Taking devantage of the property that Korean digit is a mono-syllable word, we proposed a spoken Korean-digit recognition scheme using the multi-layer perceptron. The spoken Korean-digit is divided into three segments (initial sound, medial vowel, and final consonant) based on the voice starting / ending points and a peak point in the middle of vowel sound. The feature vectors such as cepstrum, reflection coefficients, ${\Delta}$cepstrum and ${\Delta}$energy are extracted from each segment. It has been shown that cepstrum, as an input vector to the neural network, gives higher recognition rate than reflection coefficients. Regression coefficients of cepstrum did not affect as much as we expected on the recognition rate. That is because, it is believed, we extracted features from the selected stationary segments of the input speech signal. With 150 ceptral coefficients obtained from each spoken digit, we achieved correct recognition rate of 97.8%.

• Education of Primary School Mathematics
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• v.14 no.2
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• pp.117-134
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• 2011

The purpose of this research was to analyze mathematical task types to enhance creativity. Creativity is increasingly important in every field of disciplines and industries. To be excel in the 21st century, students need to have habits to think creatively in mathematics learning. The method of the research was to collect the previous research and papers concerning creativity and mathematics. To search the materials, the researcher used the search engines such as the GIL and the KISTI. The mathematical task types to enhance creativity were categorized 16 different types according to their forms and characteristics. The types of tasks include (1) requiring various strategies, (2) requiring preferences on strategies, (3) making word problems, (4) making parallel problems, (5) requiring transforming problems, (6) finding patterns and making generalization, (7) using open-ended problems, (8) asking intuition for final answers, (9) asking patterns and generalization (10) requiring role plays, (11) using literature, (12) using mathematical puzzles and games, (13) using various materials, (14) breaking patterned thinking, (15) integrating among disciplines, and (16) encouraging to change our lives. To enhance students' creativity in mathematics teaching and learning, the researcher recommended the followings: reshaping perspectives toward teaching and learning, developing and providing creativity-rich tasks, applying every day life, using open-ended tasks, using various types of tasks, having assessment ability, changing assessment system, and showing and doing creative thinking and behaviors of teachers and parents.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.372-375
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• 2008

IEEE 802.11e standardized the EDCA mechanism to support the priority based QoS. And the virtual collision handler schedules the transmission time of each MAC frame using the internal back-off window according to the access category(AC). This can provides the differentiated QoS to real-time services at the medium traffic load condition. However, the transmission delay of MAC frame for real-time services may be increased as the traffic load of best effort service increases. It becomes more critical when the real-time service uses a compressed mode video codec such as moving picture experts group(MPEG) 4 codec. That is because each frame has the different importance. That is, the I-frame has more information as compared with the P- and the B-frame. In this paper, we proposed a buffer management algorithm based on the frame importance and the delay bound. The proposed algorithm is consisted of the traffic regulator based on the dual token bucket algorithm and the active queue management algorithm. The traffic regulator reduces the transmission rate of lower AC until that the virtual collision handler can transmit an I-frame. And the active queue management discards frame based on the importance of each frame and the delay bound of head of line(HoL) frame when the channel resource is insufficient.

• Journal of Korean Medicine Rehabilitation
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• v.29 no.2
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• pp.171-188
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• 2019

Objectives The purpose of this thesis is to compare and analyze outcomes of case studies and controlled studies about Hwangryunhaedok-tang (HHT) pharmacopuncture in clinical studies. Based on these studies reporting clinical effects by using HHT pharmacopuncture, we object to deduct the comparative review in applying clinical disorders limitedly. And conclusionally, by using this comparative review, we aim to make the fine evidence in treating clinical specific diseases. Methods We searched 106 studies about HHT pharmacopuncture from 6 Korean web databases by using in Korean word 'Hwangryunhaedok-tang pharmacopuncture'. This search had been progressed throughout 1 month (January, 2019). There was 106 thesis and we excluded studies that are not related to HHT pharmacopuncture, experimental research, not the case report or randomized controlled trials, non-randomized controlled trials, not using HHT pharmacopuncture, not using only one pharmacopuncture, and not using HHT pharmacopuncture for major treating method. As a result, 39 thesis are selected as a population. Results We analyzed 34 case reports and 5 controlled studies. As the final outcome, HHT pharmacopuncture was used in musculoskeletal diseases, dermatopathy, and 32 specific diseases. Conclusions After analyzing 39 studies, effective symptom changes clinically and statistically by using HHT pharmacopuncture herbal acupuncture were identified. However, these thesis designs were reported deficiently in many parts such as not excluding other confounding variables. After modifying defects of thesis design and conduct study, it can play a role as the evidence using HHT pharmacopuncture more precisely.

• Journal of Industrial Convergence
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• v.20 no.10
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• pp.61-69
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• 2022

Posttraumatic growth literature has been rapidly expanding in multiple academic disciplines. Purpose of this study is to examine the knowledge structure of posttraumatic growth utilizing a network analysis. Papers published between 1996 and 2018 were searched on the Web of Science, focusing on terms related to posttraumatic growth. One thousand six-hundred and fifty-nine keywords were published 6,343 times in 1,780 papers; thus, a total of 322 keywords (5,195 appearances) were selected for the final analysis. The network analysis and network visualization tool used were NodeXL and PFnet, respectively. The keywords which appeared the most frequently were "Posttraumatic growth," followed by "Posttraumatic Stress Disease," "Cancer," and "Trauma." A total of 322 nodes have been reduced to 175 nodes and divided into a total of five groups. The five groups were "Posttraumatic Growth in Cancer, Chronic/Serious Illness, and Disability," "Posttraumatic Growth-related Psychological Variables and Psychotherapy," "Posttraumatic Growth in the Context of Death," "Cognitive Mechanisms of Posttraumatic Growth," and "Vicarious Posttraumatic Growth." This study provides a systematic overview on the knowledge structure of posttraumatic growth by quantitatively network analysis.

• Proceedings of the KSPS conference
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• 1996.10a
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• pp.514-514
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• 1996

Igbo, a new Benue Congo language has a vowel harmony system which, like that of Akan, is based on the pharynx size or tongue root position. In this study we examine Igbo vowel harmony with particular reference to assimilatory patterns of vowels in different harmony sets. This is to gain some insight into the factors involved in Igbo vowel assimilation, and to establish to what extent reports on Akan vowel assimilation are validated in Igbo. Tokens of the eight phonemic vowels of Standard Igbo are recorded from three native speakers of Igbo. The vowels are acoustically investigated (using the LPC analysis of CSL) in individual lexical items and within carefully designed carrier phrases. The F1 and F2 values of the vowels are obtained as these formant values are generally useful in establishing the salient characteristics of vowels. Vowels from the harmony sets are juxtaposed in the carrier phrases to ascertain the extent of assimilation. Results of the investigation show that the F1 values, to a large extend, are enough to characterize these vowels. The (-Expanded) vowels have higher F1 values than their (+Expanded) counterpart. Where there is an overlap in F1 values for some vowels the F1 bandwidth values serve to distinguish between the vowels. The overlap often reported in Akan for /I/ and /e/ on the one hand and /${\mho}$/ and /o/ on the other is not validated in Igbo. While the F1 values for these pairs of vowels are quite similar for one of our speakers, there is an appreciable difference between the F1 values of these vowels for the other two speakers. There is however an overlap for /e/ and /o/ for one of the speakers. Assimilations are generally regressive across word boundaries. It is, however, necessary to point out that the general perceptual impression that one of the vowels completely assimilates to the other, is not borne out by our investigation. Most of our F1 and F2 values for the vowels in individual lexical items are altered in assimilations. This then suggests that assimilation involving these vowels is partial rather than complete. The emerging 'allophones' are acoustically similar to the (+Expanded) vowel involved in the assimilation, that is when vowels from different harmony sets are involved. We conclude that while assimilation of Igbo vowels involves some phonological considerations, phonetic factors appear to be permanent in deciding the final form of the vowels.