• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.112-117
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• 1977

This survey was conducted to secure a basic data for the effective training programs that might be an essential part of any successful mechanization of agriculture in Korea. Chung Nam provincial training center and 17 guidance offices with farm machinery training centers which were thought to be a medium level on their scale in whole country were selected in the survey on its training accomplishments, stafts, facilities, schedule and number of trainees at one time or in a class. The results and recommendations from this survey were as follows; To enhance the effect of farm machinery training, it was absolutely necessary for city or county training center to complement its facilities and equipments. It might be desirable that instructors of each training center should be the one educated or highly trained in the institution of farm machinery, and that the number of technical assistants should be increased and their present part time working condition should be changed to full-time status. It was recommended that training for farmers should be scheduled during off-season so that farmers could participate in the training couses, and that the number of trainees in a class should be reduced to about 10 trainees, which was approximately a fourth of the present situation.

• Journal of Korea Port Economic Association
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• v.29 no.3
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• pp.159-174
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• 2013

This paper mainly deals with the appropriation of ship voyage allocation, using a heuristic regression model, in order to reduce total costs incurred in port, yard and at sea under the specific port condition. Because of different behavior of costs incurred in port, yard and at sea, an effort to minimize these costs by adjusting the number of voyages for three ship classes(50,000, 100,000, and 150,000-ton) should be made. For instance, if the port managers attempt to reduce the sea transport cost by increasing the annual allocated number of ship voyages classed 150,000-ton for economies of scale, they have no choice but to suffer a significant increase in queueing cost due to port congestion. To put it differently, there are trade-off relationships among the costs incurred in port, yard, and at sea. We utilized a computer simulation result to perform a couple of regression analyses in order to figure out the appropriate range of allocated number of voyages of each ship class using a heuristic approach. The detailed analytical results will be shown at the main paper. We also suggested a net present value(NPV) model to make a proper investment decision for an additional berth of 200,000-ton class that alleviates port congestion and reduces transport cost incurred both in port and at sea.

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.649-663
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• 1998

The clarify the ecological properties, and to predict change of understory vegetation of mt. Nam Park, population dynamics and interspecific competition of D. smilacinum and D. viridescens, which grow in understory of deciduous broad-leaved forest and pseudo-annuals, were studied from May 20 to May 30 1998. The depth of litter layer, soil moisture content, soil organic matter and soil texture were surveyed in 18 populations (15 D. smilacinum populations and 3 D. viridescens populations). Mean litter layer of d. smilacimum population was thinner than that of D. viridescens populations). Mean litter layer of D. smilacnum population was thinner than that of D. viridescens population. The contents of soil moisture and organic matter of D. smilacinum population were lower than that of D. viridescens population. The D. smilacinum growed in broad range of soil texture but D. viridescens in loamy soil. Because D. smilacinum could tolerate more broad range of soil moisture and soil texture than D. viridescens, the former covered the herb layer in earlier stage and the latter introduced in later stage when rhizome could grow easily. The numbers of individual in two marginal parts were smaller than that in center in same D. smilacinum patch. And the total numbers of individuals grown in (10 ${\times}$ 10)cm were from 0 to 12. The rhizome (subterranean runner) weight, rhizome length, root weight, shoot weight, lea weight and leaf number per subquadrat (cell) increased along the number of individual, that is, increased from marginal part to center. But rhizome weight and rhizome length per individual were vice versa. Therefore, the individuals in marginal part reproduced longer and stronger asexual propagules than that in center. The distribution pattern of D. smilacinum was contageous and that of D. viridescens was random or regular. Therefore, population growth of former was independent on density and that of latter was dependent on density. The distributions of size-class showed normal curves in two population, but the curves based on data of total dry weight showed positive skewness and those of leaf number showed negative skewness The correlation coefficient (CC) values between the properties of each organ were high in two population and significant at 0.1% level. The CC values of D. viridescens were higher of the two. Therefore, the former allocated the energy to each organ stable. The rhizome depth of d. viridescens was 2 times deeper than that of D. smilacinum. And rhizome length and weight of D. viridescens were longer (2 times) or heavier (4 times) than those of D. smilacinum. The patch size of D. viridescens increased 60 cm per year and that of D. smilacinum 30 cm. On this results, the intrinsic increase velocity of d. viridescens patch was 2 times faster than that of d. smilacinum, therefore, on the competition, the former had an advantage over D. smilacinum. The reason why d. viridescens defeated D. smilacinum resulted from that the leaf area of former was 4 times broader than that of latter. in Mt. Nam Park, it was thought that two disporum Population would change with the 3 thpes of environmental change as followings. First, no human impact and increase of soil moisture content resulted in increase of D. viridescens population. Second, mild human impact and similar condition of soil moisture content resulted in slow increase or no changes of D. smilacinum and d. viridescens population. Third, severe human impact and dry condition resulted in decrease or vanishment of two disporum populations.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.4
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• pp.446-454
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• 2017

Recently, there have been many studies on bulk-fill resin composites. However, studies on the proper materials for pediatric patients are rare. The aim of this study was to compare the cavity wall adaptation of bulk-fill resin composites with conventional resin composite in class II cavities of primary molars using microcomputed tomography (micro-CT). Standardized class II slot cavities were prepared in 80 exfoliated primary molars and randomly divided into 4 groups. The control group was restored with conventional resin composite, Filtek Z-350 XT (FZ), and the three groups were restored with bulk-fill resin composites, Filtek bulk-fill posterior (FB), Tetric N-Ceram Bulk Fill (TNC), Filtek bulk-fill flowable (FBF). All specimens were thermocycled and then immersed in 50% silver nitrate ($AgNO_3$) solution. Micro-CT was used to measure the penetration volume of the total silver nitrate and the degree of cervical marginal leakage and the number, size, and position of the voids were evaluated. The results revealed that the volume of silver nitrate were significantly different between FB and FZ (p < 0.05). The results also revealed that the penetration length of silver nitrate FBF showed statistically lower than the FZ and FB (p < 0.05). There was no significant difference between the groups in number and size of voids. In conventional resin composite, most of the voids were present inside the restoration (83.3%), but the voids in the bulk-fill resin composites incidence were higher in the gingivoaxial angle. The cavity wall adaptation demonstrated in class II restorations of primary molar by new bulk fill resin composites was similar to conventional incremental technique. Bulk-fill resin composites might be an clinical option for a faster restoration in deciduous teeth.

• Journal of The Korean Association For Science Education
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• v.37 no.6
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• pp.1025-1035
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• 2017

The purposes of this study are to analyze the merits and limits of flipped learning by suggesting the ALP model for efficient application and to test the effects of the new ALP model. The process of new model and program development is based on ADDIE in this study. This study consists of two steps. First through literature research on the difficulties of the flipped learning, the elements are extracted to develop new model. Second, these elements were placed according to the teaching and learning flow, which resulted in the procedures. As a result, the ALP model was developed. The ALP model is a new model for applying teaching and learning methods for efficient application of the flipped learning. This model was applied to elementary science classes to test its effects in scientific communication skill. Interviews and cognitive survey were also conducted to collect additional information. The results of this study are as follows: There were various difficulties in flipped learning. Based on literature research results, the ALP model and the science programs for elementary students have been developed. The experimental group showed statistically meaningful improvement in scientific communication skill. The scientific communication skill has two subcategories: the forms and the types. According to the form analysis results, the experimental group showed a statistically meaningful improvement in the form of Table and Picture, but not in the form of Writing and Number. With the same reason given previously, this study confirmed that the application of ALP model improves the students' visual form communication skills such as Table and Picture better than reading form communication skills such as Writing and Number. According to the type analysis results, the experimental group showed a statistically meaningful improvement in "the scientific insistence" type, and "the justification" which is the sub element of "the scientific insistence" type. With this reason, this study suggests that the class applied ALP model gives students more time and opportunities to learn. Though the survey and interviews about the student's awareness of the class with applied the ALP model, this study showed that students actively exchanged their opinions in the class with applied ALP model.

• Journal of KIISE:Databases
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• v.33 no.1
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• pp.102-116
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• 2006

Electronic catalogs (or e-catalogs) hold information about the goods and services offered or requested by the participants, and consequently, form the basis of an e-commerce transaction. Catalog management is complicated by a number of factors and product classification is at the core of these issues. Classification hierarchy is used for spend analysis, custom3 regulation, and product identification. Classification is the foundation on which product databases are designed, and plays a central role in almost all aspects of management and use of product information. However, product classification has received little formal treatment in terms of underlying model, operations, and semantics. We believe that the lack of a logical model for classification Introduces a number of problems not only for the classification itself but also for the product database in general. It needs to meet diverse user views to support efficient and convenient use of product information. It needs to be changed and evolved very often without breaking consistency in the cases of introduction of new products, extinction of existing products, class reorganization, and class specialization. It also needs to be merged and mapped with other classification schemes without information loss when B2B transactions occur. For these requirements, a classification scheme should be so dynamic that it takes in them within right time and cost. The existing classification schemes widely used today such as UNSPSC and eClass, however, have a lot of limitations to meet these requirements for dynamic features of classification. In this paper, we try to understand what it means to classify products and present how best to represent classification schemes so as to capture the semantics behind the classifications and facilitate mappings between them. Product information implies a plenty of semantics such as class attributes like material, time, place, etc., and integrity constraints. In this paper, we analyze the dynamic features of product databases and the limitation of existing code based classification schemes. And describe the semantic classification model, which satisfies the requirements for dynamic features oi product databases. It provides a means to explicitly and formally express more semantics for product classes and organizes class relationships into a graph. We believe the model proposed in this paper satisfies the requirements and challenges that have been raised by previous works.

• IMMUNE NETWORK
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• v.1 no.2
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• pp.135-142
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• 2001

Background: A large number of diseases occur in association with specific HLA-B or-C alleles. Recently a new gene, termed maj or histocompatibility complex class I chain-related gene A (MICA), has been identified in close proximity to HLA-B. The function of this gene is still unknown. However, it is structurally similar to HLA class I genes. MICA gene is polymorphic and is potentially associated with several diseases. Methods: To evaluate the association of MICA gene in Korean patients with human immunodeficiency virus 1 (HIV-1) infections, Polymerase chain reaction-Sequence specific primer (PCR-SSP) was done for MICA alleles in the extracellular exons, and a microsatellite analysis for GCT repeat polymorphisms in the TM exon was also completed. Results: In 199 Korean healthy controls, 7 alleles were observed and the frequencies for each allele were MICA008 (44.7%), MICA0 10 (34.2%), MICA002 (31.7%), MICA004 (23.6%), MICA0 12 (2 1.6%), MICA009 (19.6%), and MICA007 (6.5%). When 65 HIV seropositive patients were analyzed, MICA007 allele frequency was significantly higher than in controls (15.4% vs 6.5 %, RR=2.6, p<0.04). In contrast, the frequencies of other MICA alleles and microsatellite alleles in the transmembrane region of MICA gene were not significantly different between HIV seropositive patients and controls. The tight linkage between MICA alleles in the extracellular exons and GCT repeat polymorphisms in the TM exon was observed as follows; MICA002/A9, MICA004/A6, MICA007/A4, MICA008/A5.1, MICA0 10/A5, and MICA0 12/A4 in both groups. No significant difference between patients and controls was observed in the haplotype frequencies of MICA alleles in the extracellular exons and GCT repeat polymorphisms in the TM exon. Conclusion: The data suggest that immune functions related with MICA gene may affect a HIV infections.

• Journal of Environmental Science International
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• v.17 no.5
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• pp.555-564
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• 2008

The bacterial community structure in biological activated carbon (BAC) process in drinking water treatment plant was investigated by Fluorescent in situ Hybridization (FISH) with rRNA-targeted oligonucleotide probe. Samples were collected at different three points in BAC process every month for one year. They were hybridized with a probe specific for the alpha, beta, gamma subclass of the class Proteobacteria, Cytophaga-Flavobacteria group and Gram-positive high G+C content (HGC) group. Total numbers of bacteria in BAC process counted by 4',6-diamidino-2-phenylindole (DAPI) staining were $5.4{\times}10^{10}$ (top), $4.0{\times}10^{10}$ (middle) and $2.8{\times}10^{10}$ cells/ml (bottom). The number of the culturable bacteria was from $1.0{\times}10^7$ to $3.6{\times}10^7$ cells/ml and the culturability was about 0.05%. The faction of bacteria detectable by FISH with the probe EUB338 was about 83% of DAPI counts. Gamma and alpha subclass of the class Proteobacteria were predominant in BAC process and their ratios were over 20% respectively. In top and middle, alpha, beta and gamma subclass of the class Proteobacteria competed with each other and their percentages was changed according to the season. In bottom, gamma subclass of the class Proteobacteria was predominant all through the year. It could be successfully observed the seasonal distribution of bacterial community in biological activated carbon process using FISH.

• Journal of the Korean Society for Library and Information Science
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• v.15
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• pp.119-140
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• 1988

This paper is the study on the Medium Designator in Non-book materials. Main contents of this study were as follows; 1. The medium designator serves to indicate the class of material to which an item belongs. This is used to give an 'early warning' ;to the catalogue user. 2. This medium designator may be further divided into two elements ; a general material designation (GMD), for example video-recording, and a specific material designation (SMD), for example, videodisc. 3. GMD: In cataloging, a term indicating the broad class of material to which a bibliographic item belongs, such as 'motion picture', and SMD : In descriptive cataloging, a term indicating the special class of material (usually the class of physical object) to which a biblographic item belongs, such as videocassette. 4. Locating the medium designator after the title proper was not prescribed until ISBD(G) and AACR2. In pre-ISBD(G) codes, the ,early, warning type of medium designator was placed after all title information. But in AACR2, the medium designator is placed after the title proper, but before parellel title and other title information. 5. In Terminology, Two separate lists of designations are given in AACR2, l.1C1, one for British and one for North American use. The British list contains fewer terms, and uses generic categories to group together some of the North American list. 6. The problem of where to place the medium designator might be circumvented by using some kind of early alerting device other than a formal element of biblliographic description. Various alternatives have been suggested. A more popular device is the provision of symbols or 'media code' which are part of the call number and indicate the porticular medium type. 'Colour-coding' the use of used by some libraries but is now longly discouraged. 7. According to Frost. The medium designatorhas been generally reeognized as serving three functions; 1) as a statement of the nature or basic format of the item cataloged and thus as a meant of informing the user as to the type of material at hand; 2) as a description of the physical charaetistics of medium and as a means of alerting the user to equipment needed to make use of the item. 3) as a device to distinguish different physical formats which share the same title. 8. AACR2 raises some problems which decision makers have neet had to face preriously It provides a GMD for every item in the collection including books and it makes the application of any or all GMD's optional.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.929-943
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• 2016

This paper proposes the rate control algorithm based on the S-JND (Saliency-Just Noticeable Difference) model for considering perceptual visual quality. The proposed rate control algorithm employs the S-JND model to simultaneously reflect human visual sensitivity and human visual attention for considering characteristics of human visual system. During allocating bits for CTU (Coding Tree Unit) level in a rate control, the bit allocation model calculates the S-JND threshold of each CTU in a picture. The threshold of each CTU is used for adaptively allocating a proper number of bits; thus, the proposed bit allocation model can improve perceptual visual quality. For performance evaluation of the proposed algorithm, the proposed algorithm was implemented on HM 16.9 and tested for sequences in Class B and Class C under the CTC (Common Test Condition) RA (Random Access), Low-delay B and Low-delay P case. Experimental results show that the proposed method reduces the bit-rate of 2.3%, and improves BD-PSNR of 0.07dB and bit-rate accuracy of 0.06% on average. We achieved MOS improvement of 0.03 with the proposed method, compared with the conventional method based on DSCQS (Double Stimulus Continuous Quality Scale).