• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.3
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• pp.185-191
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• 2007

For the seismic performance enhancement of residential flat plate structure and for the selection of earthquake records, the possibility of base isolation is evaluated and the time history results are reviewed. By evaluating a base isolated stiffness, a target period, and an envelope curve analysis, seismic performance of structure, which has strong rotational mode, is evaluated. For the propriety evaluation of earthquake records usage and scaling method, time history analysis is done with variables such as DBE(design base earthquake) level, MCE(maximum considerable earthquake) level, and 1.4DBE level. From the analysis results, following conclusions can be made; the earthquake records, which are used in base isolation analysis, should be selected by similar soil type which the structure is considered, and should be intensity scaled in a range of mean ${\pm}$ standard deviation of code based design response spectrum.

• Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.392-409
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• 2024

The present study aims to analyze the biological aspects and population dynamics of Indian mackerel in Barru waters. Data was collected in Barru for 11 months, from June 2022 to April 2023. The observed parameters of biological aspects included gonadal maturation stages (GMSs), size at first gonadal maturation, and length-weight relationship. Meanwhile, the aspects of population dynamics encompass age group, growth, mortality rate, and exploitation rate. Data analysis consisted of morphological selection of general maturation stages, Spearman-Kärber method in estimating gonadal first maturation size, Bhattacharya method in identifying age group, von Bertalanffy function through FISAT II to measure growth (L_∞ and K), Pauly Model to estimate mortality rate, Beverton & Holt Model to estimate Y/R, and virtual population analysis (VPA) analysis to estimate stock and fish yield. The results demonstrated that GMS I was observed to be dominant, followed by stages II and III. The initial gonadal maturation was estimated to be 17.98-19.28 cm (FL) for females and 17.98-19.27 cm (FL) for males. The length-weight relationship in male and female Indian mackerels indicated a positive allometric growth. The mode grouping analysis results from the fork length measurement revealed three age groups. It was also identified that the asymptotic length (L_∞) = 29.5 cm (fork length), growth rate coefficient (K) = 0.46 per year, and theoretical age at zero length (t₀) = -0.3576 per year. Total mortality (Z) = 2.67 per year, natural mortality (M) = 1.10 per year, fishing mortality (F) = 1.57 per year, and exploitation rate (E) = 0.59, the actual Y/R = 0.083 gram/recruitment, and optimal Y/R 0.03 gram/recruitment. Fishing mortality is higher than the natural mortality rate, and a high exploitation value (E > 0.5) also reflects over-exploitation. VPA analysis on fish yields and stock estimation reported a highly exploited rate between the 11.5 cm and 14.5 cm length classes and an exceeding current yield of 467.07 tons/year with a recommended yield of 233.53 tons/year to ensure population sustainability.

• Journal of Distribution Science
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• v.10 no.1
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• pp.33-42
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• 2012

This study is focused on traditional market's competitiveness in Korea. Ever since the Korean retail industry had been opened to the big conglomerates, the traditional markets have faced very serious competition from various types of distribution channels. In particular, this study has been conducted to find another way to help the Korean traditional market from the perspective of college students who are consumers of the future. This study examines the relationships among store choice attributions, consumption emotion, consumer's value, and relationship quality from the perspective of college students. In order to verify the relationship, and moderating and mediating effects, data were collected from 126 college students in Whasung, Gyeonggi Province to test the theoretical model and its hypotheses. The results of this study are as follows: First, service (= .263, p < .01) and advertising (= .188, p < .05) are significantly positively related to relationship quality. However, store atmosphere (= .176, p = .052) is not statistically significantly related to relationship quality. The result that students have stereotypes about the atmosphere of traditional markets and are therefore excluded from their store choice attributions can be expected. Second, college students selected service division (= .230, p < .05) as the most important factor among the traditional market's store choice attributions. This result reflected that enhancing service strategy would strengthen the traditional market against discount stores. The process of product selection by customers in discount stores is based on the concept of self-service. However, traditional market traders can make various contacts with their customers. If traditional market traders can enhance various service factors just like in the process of product selection, it will effect strong competitive advantages. Third, it is also revealed that consumer's value exhibit complete mediation effect in the relationships between service and advertising. These results showed that traditional markets must be considered for consumer value. Because previous studies showed that values refer to "enduring belief that … specific mode of conduct or end-stat of existence … personally or socially preferable to an opposite of converse mode of conduct or end-state of existence" (Rokeach, 1973; George and Jones, 1996). Furthermore, Schwartz (1994) defined values as desirable trans-situational goals, varying in importance, that serve as guiding principles in the life of a person or other social entity. As conceptions of desirable end-states of existence or modes of conduct, values help people choose, evaluate, and give meaning to their experiences (Rokeach, 1973). Efforts (e.g. promote the consumers value) of the traditional market traders will improve the preferences for the traditional market of consumers and college students. Implications and future research directions are also discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.115-124
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• 1968

It was shown that the most desirable characters for kenaf are high-fiber weight and moderately early maturity. Therefore, the objectives of this research on this crop is to find varieties possessing these characteristics. The experiments covered in this report provided new information relative to segregation, mode of inheritance, estimate of the number of genes involved in fiber weight and their response to short day length of 10 hours and the qualitative characters, such as, color of stem, capsule, petiole and shape of leaves. The associations which exist among these characters are also indicated. Fiber weight per plant, days to flowering, Stem color, Petiole color, Capsule color, and shape of leaves were studied in parental, $F_1$.$F_2$and backcross populations of a cross between Dashkent, a low-fiber weight but early maturing kenaf variety, and G 38 F-1, a high-fiber weight but late maturing kenaf variety. Crosses were made using the varieties, Dashkent and G 38 F-1 as parents. The Dashkent parent had the following characteristics: green stems, capsules and petioles and lobed shaped leaves; 105.8234 mean-days to flowering in the field, and 106.9222 mean-days under 10 hours short day treatment. The other parent, G 38 F-1 had red stems yellow capsules and red petioles and unlobed shaped leaves; 149.8921 mean-days to flowering in the field, and 62.3684 mean-days under 10 hours short day treatment. Both of the parents, $F_1$, $F_2$, $BC_1$ ($F_1$ X Dashkent, ) and $BC_2$($F_1$ ${\times}$ G38F-1) of the kenaf cross were grown at the Crops Experiment Station, Suwon, Korea in 1965. Color of stems, petioles and capsules, and shape of leaves were noted to be simply inherited as a single factor. Red stem color was dominant over green stem color, red petiole color was dominant over green petiole, lobed shaped leaves were dominant over unlobed shaped leaves and yellow capsules were dominant over green capsule. It was, also, noted that the factor for color of petiole was linked with the factor for shape of leaf with a 11.9587 percent recombination value, however no interaction or linkage were found among the color of stem and capsule color. Using Powers partitioning method, theoretical means and frequency distributions for each population, the days to flowering were calculated with the assumption that two gene pairs were involved. The values obtained fitted the theoretical values. In general this would indicate that Dashkent and G 38 F -1 were differentiated by two gene pairs. Heritability values were calculated as the percent of additive genetic variance. Heritability value of days to flowering, 89.5% in the broad sense and 79.91% in the narrow sense, indicated that the selection for this character would be effective in relatively early generations. Particularly, high positive correlations were found between days to flowering and the color of petioles and shape of leaves. However, there was no relation between days to flowering and capsule color nor between these and stem color. On the basis of the results of this experiment there is evidence that the hereditary factor for shape of leaves and the color of petioles is linked with an effective factor or factors for the characters of days to flowering. The association was sufficiently close to offer a possible simple and efficient means of selection for moderately early mat. uring plants by leaf shape and petiole color selection. Again using Powers partitioning method the frequency distribution for each population to the fiber weight were calculated with the assumption that two gene pairs, AaBb, were involved. Both phenotypic and genotypic dominance were complete. The obtained value did not agree with the theoretical value for $F_2$ and $BC_1$ ($F_1$ ${\times}$ Dashkent.) It seems that Dashkent and G 38 F-1 were differentiated by two major gene pairs but some the other minor genes are necessary. It is certain that the hereditary factor for shape of leaves and color of petioles is linked with an effective factor or factors for fiber weight. Also, high. yielding plants with moderately early maturity were found in the $F_2$ population. Thus, simultaneous selection for high-fiber yield and moderately early maturing plants should be possible in these populations. Phenotypic and genotypic correlation coefficients between fiber weight per plant and days to flowering, stem height and stem diameter were calculated. In general, genotypic correlations are higher than the phenotypic correlation. The highest correlation is found between stem height and fiber weight per plant (0.7852 in genotypic and 0.4103 in phenotypic) and between days to flowering and fiber weight per plant (0.7398 in genotypic and 0.3983 in phenotypic.) It was also expected that the selection of high stem height and moderately early maturing plants were given the efficient means of selection for high fiber weight.

• Journal of Korea Water Resources Association
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• v.45 no.3
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• pp.275-290
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• 2012

In this study, we have developed an optimal time distribution model through extraction of peaks over threshold (POT) series. The median values for annual maximum rainfall dataset, which are obtained from the magnetic recording (MMR) and the automatic weather system(AWS) data at Seoul meteorological observatory, were used as the POT criteria. We also suggested the improved methodology for the time distribution of extreme rainfall compared to Huff method, which is widely used for time distributions of design rainfall. The Huff method did not consider changing in the shape of time distribution for each rainfall durations and rainfall criteria as total amount of rainfall for each rainfall events. This study have suggested an extracting methodology for rainfall events in each quartile based on interquartile range (IQR) matrix and selection for the mode quartile storm to determine the ranking cosidering weighting factors on minutely observation data. Finally, the optimal time distribution model in each rainfall duration was derived considering both data size and characteristics of distribution using kernel density function in extracted dimensionless unit rainfall hyetograph.

• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.98-105
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• 1983

The rapid increase in cases of insect resistance to insecticides indicates that the contribution of present chemical control practices inevitably leads to exhaustion of available insecticide resources against key insect species. Now the problem of insecticide resistance exists worldwide among insects and mites affecting field crops and animals including human beings, ranging from minimal or absent in some developing countries, where use of insecticides has been low, to extremely severe in many developed countries. Since the occurrence of insect resistance to insecticides was firstly recognized in 1908, the increase in recent decades has been almost linear and now the number of species of insects and acarines in which resistant strains have evolved have been increased to a total of 432. Of these, $261(60\%)$ are agricultural importance and $171(40\%)$ of medical/veterinary importance. The phenomenon of insecticide resistance is asserting itself as the greatest challenge to effective chemical control of many important insect pests. Resistance of insects to insecticides has a history of nearly 80 years, but its greatest increase and its strongest impact have occurred during the last 40 years following the discovery and extensive use of synthetic organic insecticides and acaricides. The impact of resistance should be considered not only in terms of greater cost of pest control due to increased dosages and number of applications but also in terms of the ecological disruption of pest-beneficial species density relationships, the loss of investment in the development of the insecticides concerned, and socio-economic disruption in agricultural communities. Despite its grave economic consequences, the phenomenon of insecticide resistance has received surprisingly little attention in Korea. Since the study of insecticides started firstly in 1963, many entomologists have been concerned with this study. According to their results, some of the rice pests and some of the mites on orchard trees, for example, have developed worrisome level of resistance in several areas of this peninsula. With many arthropods, considerable advances in the developed countries have been made in the study of the biochemical and physiological mechanisms of resistance. Progress involves the biochemical characteristics of specific defense mechanisms, their genetics, interactions, and their quantitative and qualitative contribution to resistance. But their studies arc still inadequately known and relatively little have been contributed in terms of unique schemes of population management in achieving satisfactory pest control. It is apparent that there is no easy solution to resistance as a general phenomenon. For future challenging to effective control of insect pests which are resistant to the insecticides concerned, new insecticide groups with distinctly novel mode of action are urgently needed. It is clear, however, that a great understanding of the factors which govern the intensity of selection of field population for resistance could lead to far more permanently successive use of chemicals within the framework of integrated pest management than heretofore practiced.

• Journal of Broadcast Engineering
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• v.25 no.2
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• pp.265-274
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• 2020

Free-viewpoint video service is a technology that allows users to watch at any angle, location and distance through interaction. In this paper, the free-viewpoint video services are defined in four viewing modes: Inward view, outward view, 3D object view and first person view. And we developed and implemented a new integrated program that plays all the suggested views. In the contents of girl band performances and basketball games, multi-view cameras suitable for each viewing mode are installed to acquire media, and data stored on the server is streamed over the network, making it available for viewing. Users can freely choose four viewing modes, space location, angle and so on, and the media data such as images and sounds are provided to them by rendering appropriately for the selected the viewpoint. Our system is expected to be a scalable free-viewpoint video service player as well as provide users with immersion and presence by combining various viewing modes.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.2
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• pp.122-129
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• 2009

Recently much attention has been paid to a guided wave due to its effective applicability to long range and fast inspection of structures. In guided wave based NDE, the appropriate selection of wave modes is one of important factors since the test performance is highly dependent on which mode of guided waves is employed. As far as plate-like structures are concerned, so far, SH guided wave has not been frequently applied compared to Lamb waves, which is mostly caused by the lack of proper and convenient transducers to generate and measure the SH waves. In this investigation, a new small-sized SH guided wave transducer based on magnetostriction is proposed. The present transducer was designed to be modular and be used with shear couplant to avoid the inconvenience of the existing magnetostrictive patch transducers, which comprises the ferromagnetic patch tightly bonded to a structure. The wave transduction mechanism and the detailed configuration of the present transducer are presented. Experimental verification is also conducted on test specimens and the results confirm the good performance of the present transducer module.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.142-146
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• 2003

To obtain information on the inheritance of grain weight and grain size of japonica cultivar, Sobibyeo which has high yielding potential and large grain in rice, the genetic variation, heritability and phenotypic correlation of 1,000 grain weight, grain length, width and thickness were investigated in two crosses, Iksan 429/Sobibyeo and Iksan 430/Sobibyeo. The gram characteristics of $\textrm{F}_1$ hybrids exceeded mid-parental values, while grain length: width ratio was intermediate between the parents. In $\textrm{F}_2$ populations, the average grain length, width and thickness were intermediate as mid-parental values, but grain weight exceeded the mid-parental values. In $\textrm{F}_2$ populations of Iksan 429/Sobibyeo and Iksan 430/Sobibyeo, mean 1,000 grain weights were 24.86g and 25.04 g on the average, and ranged 18.4g-32.2g and 19.5g-33.4g, respectively. The segregation mode for grain weight was regarded as a nearly normal distribution in two crosses of $\textrm{F}_2$ populations. Estimates of broad sense heritabilities for grain weight in Iksan 429/Sobibyeo and Iksan 430/Sobibyeo were high as 89.00% and 89.06%, and grain length showed the highest heritability among grain characteristics as 97.45% and 97.35%, respectively. Grain weight was highly correlated with grain length, width and thickness, and grain length was highly correlated with grain width and thickness. These grain characteristics were apparently controlled by polygenes. Accordingly, these traits will be readily improved through selection in the early segregating generations.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.36-47
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• 2016

This study was conducted to evaluate five different strains of rhizobacterial isolates viz. PA1, PA2, PA4, PA5 and PA12 for biological control against Colletotrichum acutatum, C. coccodes, C. gloeosporioides, C. dematium, Botrytis cinerea, Rhizoctonia solani, Sclerotinia minor and Fusarium sp. In vitro inhibition assay was performed on three different growth mediums, potato dextrose agar (PDA), tryptic soy agar (TSA), and PDA-TSA (1:1 v/v) for the selection of potential antagonistic isolates. According to the result, isolate PA2 showed the highest inhibitory effect with 65.5% against C. coccodes on PDA and with 96.5% against S. minor on TSA. However, the same isolate showed the highest inhibition with 58.5% against C. acutatum on PDA-TSA. In addition, an in vivo experiment was performed to evaluate these bacterial isolates for biological control against fungal pathogens. Plants treated with bacteria were analyzed with phytopathogens and plants inoculated with phytopathogens were treated with isolates to determine the biological control effect against fungi. According to the result, all five isolates tested showed inhibitory effects against phytopathogens at various levels. Mode of action of these rhizobacterial isolates was evaluated with siderophore production, protease assay, chitinase assay and phosphate solubilizing assay. Bacterial isolates were identified by 16S rDNA sequencing, which showed that isolates PA1 and PA2 belong to Bacillus subtilis, whereas, PA4, PA5, and PA12 were identified as Bacilus altitudinis, Paenibacillus polymyxa and Bacillus amyloliquefaciens, respectively. Results of the current study suggest that rhizobacterial isolates can be used for the plant growth promoting rhizobacteria (PGPR) effect as well as for biological control of various phytopathogens.