• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.1
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• pp.57-70
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• 2009

Considerable advance has been made on research on effect of steel pipe Umbrella Arch Method (UAM) and mechanical reinforcement mechanism through numerical analyses and experiments. Due to long analysis time of three-dimensional analysis and its complexity, un-quantitative two-dimensional analysis is dominantly used in the design and application, where equivalent material properties of UAM reinforced area and ground are used, For this reason, development of reasonable, theoretical, quantitative and easy to use design and analysis method is required. In this study, both field UAM tests and laboratory tests were performed in the residual soil to highly weathered rock; field tests to observe the range of reinforcement, and laboratory tests to investigate the change of material properties between prior to and after UAM reinforcement. It has been observed that the increase in material property of neighboring ground is negligible, and that only stiffness of steel pipe and cement column formed inside the steel pipe and the gap between steel pipe and borehole contributes to ground reinforcement. Based on these results and concept of Convergence Confinement Method (CCM), two dimensional axisymmetric analyses have been performed to obtain the longitudinal displacement profile (LDP) corresponding to arching effect of tunnel face, UAM effect and effect of supports. In addition, modified load distribution method in two dimensional plane-strain analysis has been suggested, in which effect of UAM is transformed to internal pressure and modified load distribution ratios are suggested. Comparison between the modified method and conventional method shows that larger displacement occur in the conventional method than that in the modified method although it may be different depending on ground condition, depth and size of tunnel, types of steel pipe and initial stress state. Consequently, it can be concluded that the effect of UAM as a beam in a longitudinal direction is not considered properly in the conventional method.

• The Korean Journal of Zoology
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• v.14 no.3
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• pp.139-158
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• 1971

This study was initiated to observe the growth of the lengths of the body, the antenna, the rostrum, the fore leg, the middle leg, the hind leg and the width of pronotum in the postembryonic development of Anoplocnemis dallasi. The specimens measured were fifty in the first instar larva and seventy for each instar from the second instar larva to adult stage. The authors applied the growth formula and the relative growth formula to analyse the changing pattern of the growth of each part. In this paper, having applied the formulae the y=a+bt+$ct^2$ for the absolute growth and $y=bx^{\alpha}$ for the relative growth, we obtained the following results: $\circled1$ The growth quantity: The rostrum shows the slowest, straight increase, but the other shows the curving increase. The body, the hind leg, the middle leg, the fore leg, the antenna, the width of pronotum and the rostrum are systematically slow. $\circled2$ The ratio of the growth quantity: The increase rate of the rostrum shows the straight, while the other shows the curving patterns. The largest value is the increase rate of the width of pronotum (8.816 times) and the smallest one is the rostrum (3.054 times). $\circled3$ The growth ratio for each instar: The maximal ratio of the growth quantity is in the young instar larva, but the minimal one is in an advanced instar larva. $\circled4$ The growth rate: The antenna shows a decrease pattern, while the other an increase pattern. $\circled5$ The specific growth rate: The rates of the antenna, the for leg, the rostrum, the hind leg and the middle leg show a decrease pattern. In the width of pronotum and the body, they increase in the terms of the young instar larva and they increase later. The antenna shows the most rapid decrease, and the fore leg, the rostrum, the hind and the middle leg are slow in order. $\circled6$ The "$\alpha$" of the width of pronotum shows the strongest positive allometry, but the rostrum shows the weakest negative allometry to all parts. $\circled7$ The coefficient of the relative growth of each part shows a parallel fashion in the relative growth to body length, to width of pronotum, to antenna, to rostrum, to fore leg, to middle leg and to hind leg. $\circled8$ If the coefficient of the relative growth, the growth ratio ($\alpha$) increase, the initial growth index (b) is disposed to decrease and vice versa. $\circled9$ The growth center is in the terms of the young instar larva in case of the negative allometry, but it is in the terms of an advanced instar larva in case of the positive allometry.

• The Korean Journal of Zoology
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• v.15 no.1
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• pp.25-33
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• 1972

Two-Cell mouse embryos were incubated in the anterior chamber of the rat eye, which has been known as the best place among other animals' for the mouse ovum maturation, in order to observe the capability of their early development. Within 120 hours after incubation, 71.0% of two-cell embryos have developed to the blastocysts in the male rat eye, while only 38.5% in the eye of the same mouse as donated two-cell embryos. Thus, the rat eye chamber provides more favourable environment to the embryos than the mouse itself. The results are consistent with those of the previous studies comparing the maturation of the mouse follicular oocytes in the mouse and the rat eye chamber. Although the aqueous humor which is filled in the anterior chamber of the eye is characterized by its specific properties, being of higher osmolarity, higher concentrations of ascorbic acid, pyruvate and lactate, but lower of proteins and lower temperature than those in blood or lymph serum, The embryos are able to under-take their cleavage as normal as in vivo or in vitro. Concerning with a number of studies in vitro on the development of the mouse embryos which are requiring a very limited condition, the fact that they are able to manage their further development under very different enviroment from our knowledges would provide us a moment to understand their behavior during the early development. The difference of the proportion of the developed blastocysts between in the mouse eye chamber and in the rat can possibly be resulted from the species specific difference in the physicochemical properties between their eye chambers. This assumption is based upon the findings by many investigators who chmpared the nature of the eye chamber of various animals. As a consequence, the rat eye chamber might consist of better properties for the embryonal growth than the mouse eye chamber. The mouse embryos cleaved with a delayed period. In normal development they complete almost the cleavage within 94 hours after fertilization. However, in the present studies, 81.1% of two-cell embryos developed to the blastocysts and the morula in 120 hours in the eye chamber, assumed to be about 154 hours after fertilization. Such delay in development would be caused mainly by the low temperature of the eye chamber. At present we can make two assumptions to explain the capability of the emtryonal development in the eye chambers. One is that the embryos would possess an ability to adapt themselves to the environment which provides unfavourable conditions. The other is that the embryos might remain for a certain duration in the eye chamber, which is filled with a new body fluid produced immediately after the loss of the aqueous humor and the fluid of which becomes similar to blood serum in component. The first assumption is highly reliable since the embryonal cells are mostly at the undifferentiated state and so they probably engage a simple metabolism during their early period. The second assumption is induced by the fact that the rabbit eye chamber produces a plasmoid humor which has mostly similar components to blood serum after loss of aqueous humor through cornea by puncturing. However, the plasmoid humor is substituted by the initial aqueous humor in eight hours. Even though this finding, production of the new fluid, could be applied to the rat eye, it is hardly reliabel that the plasmoid humor remains for such a long period as 120 hours. Consequently, the development of the embryos is more likely due to their adaptability to the new environment during their early developmental stages.

• (The) Research of the performance art and culture
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• no.39
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• pp.69-96
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• 2019

North Korea has conserved operas in a selective manner. The subject matters of operas recorded in the history of North Korea can be divided into classical tales, translated foreign works, Korean War and war against Japan. Operas that adapted folk classics of the 1950s are considered valuable materials to verify the changes of genres posterior to division of regime between North and South Korea. The officially confirmed works include "Kumgangsan Palseonnyeo (Gyeonwoo Jiknyeo)," "Chunhyangjeon." "Kongjwi Patjwi (Kotsin)," "Ondal," and "Geumnaneui Dal." These works had gone through recreation in terms of realistic situation setting, abolition of class difference, adjustment of social rank and punishment of evil while the base lies in the original folk classics. People emphasized in adapted folk operas are described as those who are hard-working souls without giving importance of difference of social rank, content with the currently living space, devoted to their parents and full of patriotic spirit, and members of community who participate in organized fights against unfair exploitation. This was the fruit of encouragement of work creation supporting union between labor and individual life, destruction of old things and fight promoting this destruction. Folk operas of South and North Korea posterior to Korean War have similarities in that both deal with a love story transcending social ranks and the concomitant conflicts and they focus on the audience who enjoy the operas. Nonetheless, they are different in that this love in North Korea became a tool of educating people wished by the regime, while it became an object of securing the audience by adding the tragic element to love in South Korea. North Korean operas of the initial stage are characterized by playwriting method emphasizing difficult life and compensation of common people, realistic stage expression, accentuation of melody and agreement between notes and lyrics. This was efforts designed to continuously lead senses concentrated from the theater to everyday life of people. In effect, this is in line with the playwriting method of revolutionary operas. Adapted folk operas were subject matters ideal for easily approaching the audience and leaving them good memories at the same time. To realize socialist realism, they went through an experiment of reviewing "people" through the classic folk operas. The possibility of continuation of a work was determined by thorough evaluation after carrying out an experiment in terms of subject matters, theme, music and operation plans from the moment of which the work was on the stage. The sign consisted in the possibility of visit of "Kim Il-sung" to appreciate the work and presentation of directionality. By proposing the clear directionality of which hard-working people who deny social status system can be duly compensated, it encouraged the audience who saw the opera to voluntarily put this in practice. Thus, operas established the directionality through selective processes for creating public communion even before revolutionary operas.

• Asia Marketing Journal
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• v.12 no.3
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• pp.1-24
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• 2010

Typically, marketing literature on innovation diffusion has focused on the pre-adoption process and only a few studies explicitly examined consumers' post-adoption behavior of innovative mobile services. Besides, prior use diffusion research has considered the variables that determine the consumers' initial adoption in explaining the post adoption usage behavior. However, behavioral sciences and individual psychology suggest that social influences are a potentially important determinant of usage behavior as well. The purpose of this study is to investigate into the effects of network factor and brand identification as social influences on the consumers' use diffusion or continued usage intention of a mobile service. Network factor designates consumer perception of the usefulness of a network, which embraces the concept of network externality and that of critical mass. Brand identification captures distinct aspects of social influence on technology acceptance that is not captured by subjective norm in situations where the technology use is voluntary. Additionally, this study explores the effect of the use diffusion on the brand switching intention, a generally unexplored form of post-adoption behavior. There are only a few empirical studies in the literature addressing the issue of IT user switching. In this study, the use diffusion comprises of rate of use and variety of use. The research hypotheses are as follows; H1. Network factor will have a positive influence on the rate of use of mobile services. H2. Network factor will have a positive influence on variety of use of mobile services. H3. Network factor will have a positive influence on continued usage intention. H4. Brand identification will have a positive influence on the rate of use. H5. Brand identification will have a positive influence on variety of use. H6. Brand identification will have a positive influence on continued usage intention. H7. Rate of use of mobile services are positively related to continued usage intention. H8. Variety of Use of mobile services are positively related to continued usage intention. H9. Rate of use of mobile services are negatively related to brand switching intention. H10. Variety of Use of mobile services are negatively related to brand switching intention. With the assistance of a marketing service company, a total of 1023 questionnaires from an online survey were collected. The survey was conducted only on those who have received or given a mobile service called "Gifticon". Those who answered insincerely were excluded from the analysis, so we had 936 observations available for a further stage of data analysis. We used structural equation modeling and overall fit was good enough (CFI=0.933, TLI=0.903, RMSEA=0.081). The results show that network factor and brand identification significantly increase the rate of use. But only brand identification increases variety of use. Also, network factor, brand identification and the use diffusion are positively related to continued usage intention. But the hypotheses that the use diffusion are positively related to brand switching intention were rejected. This result implies that continued usage intention cannot guarantee reducing brand switching intention.

• Asia Marketing Journal
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• v.11 no.4
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• pp.95-119
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• 2010

Although there have been many studies regarding the inconsistency between consumers' attitudes and behavior, prior research has almost exclusively focused on the relationship between the attitude before behavior and the initial behavior. Relatively little research has been conducted on consumer satisfaction after purchase and post-purchase behavior. This research proposed that the relationship between satisfaction and post-purchase behavior is moderated by consumers' psychological characteristics such as need for cognitive closure(NCC) and temporal self-construal(SC). The need for cognitive closure refers to individuals' desire for a firm answer to a question and an aversion toward ambiguity. We assumed the need for cognitive closure as a major moderating variable because it is judged that the requirement for cognition clearly varies between when a consumer repurchases the same product and seeks a new alternative. Individuals who tend to end cognition due to time constraints or inappropriate conditions may display considerable cognitive impatience or impulsivity and has a higher probability in repurchasing the same product than a consumer without such limitations. They would avoid further consideration for new alternatives and the likelihood of the repurchase for prior alternative would increase. As hypothesized, significant moderating effect of the NCC was confirmed. This result gives a significant implication for a corporate to establish effective marketing strategies. For a corporate or product brand that has been occupying the market after entering the market earlier, it would be effective to maintain need for cognitive closure high in the existing consumers and thereby preventing the consumers from being interested in the new alternatives. On the other hand, new brands that have just entered the market need to lower the potential consumers' need for cognitive closure so that the consumers can be interested in new alternatives. Along with need for cognitive closure, temporal self-construal also turned out to moderate the satisfaction-repurchase. temporal SC reflects the extent to which individuals view themselves either as an individuated entity or in relation to others. Consumers under a temporarily independent SC would repurchase former alternative again according to their prior satisfaction and evaluation. In contrast, consumers in temporal interdependent SC tended to switch to a new alternative because they value interpersonal relationships above anything else and have a tendency to rely heavily on in-group opinions. When they are confronted with additional opinions, it is highly probable that he/she will choose a new product as an alternative. By proving the impact that temporal self-construal has on repurchasing behavior, this study is providing the marketers with new standards for establishing successful promotional strategies. For example, if the buyer and the user is the same for a product, it would be effective for the seller to convince the consumer to make decision subjectively by encouraging temporal independent self-construal. On the contrary, in the case where the purchase is made by an individual but the product is consumed by a group of people. For example, a housewife is more likely to choose the products or brands that her husband or children prefer rather than the ones that she likes by herself. In that case, emphasizing how the whole family can be satisfied and happy about the product would be effective for promoting repurchase.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.453-460
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• 2023

This study was conducted to confirm the growth performance of Hanwoo steers according to the crude protein and calcium levels and their effects on carcass characteristics. The experiment consisted of a total of 4 groups: HPHC (CP 15%, Ca 1.2%), HPLC (CP 15%, Ca 0.6%), LPHC (CP 12.5%, Ca 1.2%), LPLC (CP 12.5%, Ca 0.6%). In the feeding trial, Hanwoo steers (650.8±16.27 kg, n = 32, 24 months of age) were divided into four feeding groups (n = 8 each) with the same initial body weight. Animals were fed with each rice straw and concentrate (1:9) until the late fattening stage. Growth performance was measured by daily weight gain, feed conversion rate, and final weight. Carcass characteristics were measured carcass weight, loin area, back-fat thickness and marbling score. There was no significant difference in growth performance and carcass characteristics among the treatment groups. However, the ratio of meat quality grade 1⁺ or higher was 76% in LPLC, which was higher than other treatments (HPHC, 63%; HPLC, 63% and LPHC, 50%). Therefore, reducing crude protein in the feed did not affect growth and carcass characteristics. In addition, calcium control in the late fattening stage did not affect growth performance. In LPLC, the ratio of meat quality 1⁺ or higher was the highest, so additional research on calcium control in feed is thought to be necessary. However, there was no significant difference in the relationship between protein and calcium levels in feed in all study results, so the influence of the two factors on each other is thought to be low.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.129-141
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• 2023

Crop models have been used to predict yield under diverse environmental and cultivation conditions, which can be used to support decisions on the management of forage crop. Cultivar parameters are one of required inputs to crop models in order to represent genetic properties for a given forage cultivar. The objectives of this study were to compare calibration and ensemble approaches in order to minimize the uncertainty of crop yield estimates using the SIMPLE crop model. Cultivar parameters were calibrated using Log-likelihood (LL) and Generic Composite Similarity Measure (GCSM) as an objective function for Metropolis-Hastings (MH) algorithm. In total, 20 sets of cultivar parameters were generated for each method. Two types of ensemble approach. First type of ensemble approach was the average of model outputs (E_em), using individual parameters. The second ensemble approach was model output (E_pm) of cultivar parameter obtained by averaging given 20 sets of parameters. Comparison was done for each cultivar and for each error calculation methods. 'Jowoo' and 'Yeongwoo', which are forage rice cultivars used in Korea, were subject to the parameter calibration. Yield data were obtained from experiment fields at Suwon, Jeonju, Naju and I ksan. Data for 2013, 2014 and 2016 were used for parameter calibration. For validation, yield data reported from 2016 to 2018 at Suwon was used. Initial calibration indicated that genetic coefficients obtained by LL were distributed in a narrower range than coefficients obtained by GCSM. A two-sample t-test was performed to compare between different methods of ensemble approaches and no significant difference was found between them. Uncertainty of GCSM can be neutralized by adjusting the acceptance probability. The other ensemble method (E_pm) indicates that the uncertainty can be reduced with less computation using ensemble approach.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.325-334
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• 2023

The invasive red swamp crayfish, Procambarus clarkii, is native to south-central United States and northeastern Mexico. Recently, it has been being spreading in the wild in South Korea. However, its primary sources, introduction routes, establishment, and expansion in South Korea remain unclear. Here, we analyzed genetic diversity and population genetic structures of its domestic natural populations during early invasion, commercial stock from local aquaria (a suspected introduction source), and original United States population using mitochondrial COI gene sequences for 267 individuals and eight microsatellite markers for 158 individuals. Natural and commercial populations of P. clarkii showed reduced genetic diversity (e.g., haplotype diversity and allelic richness). The highest genetic diversity was observed in one original source population based on both genetic markers. Despite a large number of individuals in commercial aquaria, we detected remarkably low genetic diversity and only three haplotypes among 226 individuals, suggesting an inbred population likely originating from a small founder group. Additionally, the low genetic diversity in the natural population indicates a small effective population size during early establishment of P. clarkii in South Korea. Interestingly, genetic differentiation between natural populations and the United States population was lower than that between natural populations and aquarium populations. This suggests that various genetic types from the United States likely have entered different domestic aquariums, leading to distinct natural populations through separate pathways. Results of our study will provide an insight on the level of genetic divergence and population differentiation during the initial stage of invasion of non-indigenous species into new environments.