• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.187-192
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• 2015

In general, design of urban intersections are fundamentally different from rural intersections, but current urban intersection design has been appled to rural standards. This study has suggested the design standard for urban intersection grades based on the existing literature, field investigating and comparative analysis. Moreover, this study analyzes and compares the differences between urban and rural intersections, and intersections have been derived by appropriate design standards after reviewing the domestic and international grades design criteria. Site survey was performed to validate the derived design criteria by analyzing statistically to establish the design standards. Results were produced for the intersection portion grade standards by comparing the number of instructions which produced appropriate slope degree from 2.5% to 3% in normal condition and slope can be extended to 5% in some critical cases. In-situ investigation was performed to validate the produced data where slope was found from 0.0~8.6%. Additional data of accident analysis were also collected for the validation of the suggested data and correlation analysis was performed using the SPSS tool. Data were analyzed statistically using 95% significance level for vehicle-to-vehicle collided, head-on collision accident rates, where accident rates significantly correlated with the grade. Therefore, appropriate grade at the intersection should be designed and applied in order to reduce the number of accidents at the intersection. Finally, appropriate grades for urban intersections are suggested from 1-3% for normal cases and grades could extend up to 5% for unavoidable cases where extra care must be taken when designing.

• Fire Science and Engineering
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• v.26 no.1
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• pp.43-48
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• 2012

Recently, evacuation safety of building resident become the major concern, as the building has been higher and more complicated. Required evacuation time using stairway is longer in high-rise buildings, moreover it is impossible for the disabled to evacuate by using stairway. For this reason the study on the effectiveness of using elevator for evacuation is progressing. This study shows the flow coefficient of hoistway when elevator is moving. The results of this study can be used for the study of elevator piston effect as basic data. Experiments were performed in 5 different hoistways at 3-story and 2-story buildings. According to the result of flow coefficient experiments, average flow coefficient is 0.954. Considering the $4{\sigma}$ to guarantee 99.99 % reliance, it is 0.86. This result is 3.6 % bigger than 0.83 that Klote and Tamura suggested. It represents that the maximum critical pressure is decreased about 7 % on the same condition of elevator and elevator shaft. When the smoke control performance of high-rise building is evaluated, the result is significant economically by applying a more realistic and less value of elevator piston effect.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.347-354
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• 2009

This study was conducted on the biological control effects of the natural enemy, Amblyseius cucumeris, against Polyphagotarsonemus latus. The broad mite moved to a new habitat after the carrying capacity of the preferred habitat on the upper leaf has been reached. Population dynamics between predator, Amblyseius cucumeris, and prey, P. latus, were quite well synchronized since the predator followed the movement of the prey. In predation test by Amblyseius cucumeris on P. latus, A. cucumeris fed on 8.8, 15.2, 27.0 and 30.3 individuals/day under the temperatures of 15, 20, 25, and $30^{\circ}C$, respectively. The A. cucumeris larva, protonymph, deutonymph, adult male, and adult female fed on 0.5, 1.6, 5.2, 3.8, and 27 individuals of adult P. latus per day, respectively, under $25^{\circ}C$ condition. The functional response curve of adult P. latus to the densities of A. cucumeris showed Holling's Type II curve. The consumption of prey by A. cucumeris increased with the prey density increase, but the consumption rate decreased. The critical ratio of predator vs. prey effectively to suppress (98% over) the population of P. latus by releasing A. cucumeris was 1:40 on red pepper.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.125-137
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• 2010

Jongmyo royal shrine, located in Seoul, is a UNESCO World Heritage site, and a cultural relic of national value and significance. Examination of its udobakseok(granitic flagstone; thin, flat and even stepping-stones for the King) has shown that parts are in damaged condition. In this study, GIS and GPS technologies were applied to determine the extent of damage and to find granitic flagstone for replacement and restoration of the damaged stones. 1,158 out of 2,361 stone pieces of the udobakseok were damaged at Jongmyo. Replacement granitic flagstones are available on Seokmo Island, in Ganghwa County, and estimates show that approximately 100,000 pieces of stone can be quarried. This research aided the systematic management of information about availability and location of granitic flagstones for restoration of the Jongmyo udobakseok. It also demonstrated that GIS and GPS technologies can apply a critical role in managing cultural properties. The wide use of GIS and GPS technologies can be expected for survey and management of other cultural properties in addition to Jongmyo.

• International Commerce and Information Review
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• v.16 no.4
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• pp.263-280
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• 2014

The dynamics of global alliance networks can be analyzed in numerous ways. We have chosen to approach it in terms of alliance stability. Although increasing academic attention has been devoted to the alliance dynamics field, the majority of prior research has neither contributed to a coherent knowledge foundation(an academic gap) nor provided adequate answers to managerial questions(a managerial relevance gap). We respond to their call for research by developing an integrated process model that integrates various studies on alliance stability. The primary tasks were (1) to characterize and conceptualize the stability concept to fill the academic gap, and (2) to identify critical endogenous factors underlying alliance stability over the different developmental stages to fill the managerial gap. Knowledge acquired in this paper is also expected to offer alliance managers and practitioners some valuable implications as they strive for stable and successful collaborative relationships. As one of the basic arguments, stability has been viewed as a necessary condition for the achievement of collaborative objectives. When firms form, implement, adjust and evaluate their alliances, they should have the goal of stability in mind. At the same time, management should be in a position to determine the specific actions needed for stability at any given moment in the alliance's lifetime.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.5
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• pp.94-104
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• 2000

The accuracy and reliability of the target tracking is very critical issue in the design of automotive collision warning radar A significant problem in multi-target tracking (MTT) is the target-to-measurement data association If an incorrect measurement is associated with a target, the target could diverge the track and be prematurely terminated or cause other targets to also diverge the track. Most methods for target-to-measurement data association tend to coalesce neighboring targets Therefore, many algorithms have been developed to solve this data association problem. In this paper, a new multi-target data association method based on order statistics is described The new approaches. called the order statistics probabilistic data association (OSPDA) and the order statistics joint probabilistic data association (OSJPDA), are formulated using the association probabilities of the probabilistic data association (PDA) and the joint probabilistic data association (JPDA) filters, respectively Using the decision logic. an optimal or near optimal target-to-measurement data association is made A computer simulation of the proposed method in a heavy cluttered condition is given, including a comparison With the nearest-neighbor CNN). the PDA, and the JPDA filters, Simulation results show that the performances of the OSPDA filter and the OSJPDA filter are superior to those of the PDA filter and the JPDA filter in terms of tracking accuracy about 18% and 19%, respectively In addition, the proposed method is implemented using a developed digital signal processing (DSP) board which can be interfaced with the engine control unit (ECU) of car engine and with the d?xer through the controller area network (CAN)

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.4
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• pp.521-525
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• 2006

The present study was undertaken to evaluate the effect of flushing of ewes with concentrate pellets just before the mating season on their nutrient utilization and reproductive performance on farms. Forty-eight Malpura ewes, 1-5 years old were randomly divided into 2 groups of 24 each (G1and G2). Ewes in both the groups were grazed on natural rangeland from 07.00 to 18.00 hr followed by night shelter in animal shed. G1 ewes were maintained on sole grazing while G2 ewes, in addition to grazing, received concentrate pellets at the rate of 1.5% of their body weight. The mean biomass yield of the community rangeland was 0.46 ton DM/hectare. The intakes of DM (g/kg $W^{0.75}$), DCP (g/kg $W^{0.75}$) and ME (MJ/kg $W^{0.75}$) were higher (p<0.01) in G2 as compared to that of G1 being 86.5, 10.2 and 1.15 and 57.5, 4.7 and 0.75, respectively. The digestibility of DM, OM, CP, NDF and hemicellulose were also higher (p<0.01) in G2 as compared to that of G1 being 57.2, 76.7, 78.9, 51.9 and 81.6 and 50.8, 68.7, 68.4, 45.4 and 74.4, respectively. The conception rate was higher (79.2%) in flushed ewes as compared to that of non-flushed (66.7%). Five of the pregnant ewes died and another 5 aborted in G1 while in G2, 5 ewes aborted with no mortality. The lambing was higher (73.7%) in G2 than that in G1 (37.5%). The birth weight of lambs was higher (p<0.05) in G2 (3.47 kg) than that in G1 (2.95 kg). Further, the birth weight of male lambs was higher (3.28) than that of female lambs (3.14). It is concluded that the biomass yield of the community rangeland in semi-arid region of India is low and insufficient to meet the nutrient requirement of ewes prior to mating season. However, concentrate supplementation at the rate of 1.5% of body weight to ewes during this critical stage enhanced their plane of nutrition, reproductive performance, body condition and birth weights of lambs.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.1
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• pp.106-114
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• 2018

The aim of this study was to empirical understanding on the impact of work environment on the job satisfaction among the landscape architecture workers through conduct survey. The results was found that the affecting factors of environment in landscape architecture workers were work environment, personal relationship, and job compensation on jab satisfaction, but were not affected between workload and job satisfaction (p<0.05). And this implied that personal relationship in job environment factors was critical factor to decide the levels of job satisfaction (${\beta}$ value 0.233) across the landscape architecture workers. The results guessed the factor that workload among the job satisfaction is or is not statistical significant in many research were because it depends on whether the task is passively recognized or positive recognized according to the job recognition situation. The results was guessed the fact that the affecting factors of the workload among the job satisfaction of landscape architecture workers is not statistical significant were because they have their works cut out for them, makes worthwhile if they thinks that were meaningful and feel have been growing capabilities and recognized that there is a social contribution, and feel the great sense of accomplishment of self-development and self-realization nevertheless they have much their's works.

• Communications of Mathematical Education
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• v.30 no.3
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• pp.393-418
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• 2016

Theory and fundamentals of mathematics consist mostly of proposition form. Activities by research of the proposition which leads to determine the true or false, justify the true propositions and refute with counterexample improve logical reasoning skills of students in emphases on mathematics education. Also, utilizing of counterexamples in school mathematics combines mathematical knowledge through the process of finding a counterexample, help the concept study and increase the critical thinking. These effects have been found through previous research. But many studies say that the learners have difficulty in generating counterexamples for false propositions and materials have not been developed a lot for the counterexample utilizing that can be applied in schools. So, this study analyzed the current textbook and examined the use of counterexamples and developed educational materials for counterexamples that can be applied at schools. That materials consisted of making true & false propositions and students was divided into three groups of academic achievement level. And then this study looked at the change of the students' thinking after counterexample classes. As a study result, in all three groups was showed a positive change in the cognitive domain and affective domain. Especially, in top-level group was mainly showed a positive change in the cognitive domain, in upper-middle group was mainly showed in the cognitive and the affective domain, in the sub-group was mainly found a positive change in the affective domain. Also in this study shows that the class that makes true or false propositions in education of utilizing counterexample, made students understand a given proposition, pay attention to easily overlooked condition, carefully observe symbol sign and change thinking of cognitive domain helping concept learning regardless of academic achievement levels of learners. Also, that class gave positive affect to affective domain that increase interest in the proposition and gain confidence about proposition.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.1
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• pp.7-12
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• 1977

This experiment was conducted in the laboratory in order to find out the relationships between the root growth and soil physical properties. The soils selected for this study were Sangju sandy loam, Yeongog loam, Hwadong silty clay loam, which have been considered to be a typical upland soils of Korea. Artificial core samples were made with various moisture contents and bulk densities. Elongation rate of pea seedling taproot and soil strength were measured respectively in these core samples. The results obtained are summarized as follows: 1. The soil strength increased with the bulk density and deceased with moisture content. 2. The correlation between root elongation and soil bulk density was significantly recognized at the same moisture content and the root elongation was influenced by the bulk density more significantly at dry condition. 3. The elongation rate of pea seedling taproot was significantly decreased by increasing the strength (Yamanaka tester and Fine probe) of the soils. 4. The soil strength of $21kg/cm^2$ in fine metal probe or 24mm in Yamanaka tester was considered to be the critical point for plant growth, which was restricting root elongation smaller than 1/4 of the maximum growth rate.