• International conference on construction engineering and project management
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• 2005.10a
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• pp.886-891
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• 2005

The frequent maintenance required on some asphalt concrete (AC) pavement sections has made reconstruction with Portland Cement Concrete Pavement (PCCP) a feasible alternative. However, many constructability issues need to be addressed in order to realize the full potential of this alternative. Accelerated paving encompasses three classes of activities: methods to accelerate the rate of strength gain, methods to minimize the construction time, and traffic control strategies to minimize user delay. Three major AC intersections with severe rutting problems were reconstructed with PCCP. The entire reconstruction of each intersection, including demolition of the AC pavement and its replacement with PCCP, took place over a period of three days, starting on Thursday evening and opening the intersection to the traffic on Sunday afternoon. This paper discusses the use of PCCP for accelerated reconstruction of major urban intersections with minimal user and traffic disruption, using innovative construction techniques and traffic management optimization principles and demonstrates that concrete pavements can be constructed efficiently and quickly.

• Journal of Plant Biology
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• v.33 no.3
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• pp.197-202
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• 1990

Exogenously applied spermine, spermidine and putrescine caused a delay of senescence in fronds Lemna gibba G3 under continuous illumination. When the proximal half of a frond containing the meristematic“pockets”was removed, endogenous spermidine level in the distal half (half frond) increased initially to a miximal level, which was followed by a decline during a period of 10 days of incubation in light. No appreciable changes were observed with putrescine or spermine levels. Treatment of fronds with $\alpha$-difluromethylarginine (DFMA) resulted in both reduced level of spermidine and enhancement of chlorophyll loss in half fronds. $\alpha$-difluoromethylornithine (DFMO) was found to be virtually ineffective in either parameter. Results of experiments with ABA and kinetin indicate that there is a close correlation between the progress of senescence and spermidine level in Lemna fronds under illumination. It is suggested that endogenous level of spermidine is associated, at least in part, with frond senescence in this aquatic plant.

• Journal of KIISE
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• v.41 no.11
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• pp.974-981
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• 2014

These days, use of multimedia streaming service and demand of QoS (Quality of Service) improvement have been increased because of development of network. QoS of streaming service is influenced by a jitter, delay, throughput, and loss rate. For guaranteeing these factors which are influencing QoS, the role of transport layer is very important. But existing TCP which is a typical transport layer protocol increases the size of congestion window slowly and decreases the size of a congestion window drastically. These TCP characteristic have a problem which cannot guarantee the QoS of UHD multimedia streaming service. In this paper, we propose a router buffer based congestion control method for improving the QoS of UHD streaming services. Our proposed scheme applies congestion window growth rate differentially according to a degree of congestion for preventing an excess of available bandwidth and maintaining a high bandwidth occupied. Also, our proposed scheme can control the size of congestion window according to a change of delay. After comparing with other congestion control protocols in the jitter, throughput, and loss rate, we found that our proposed scheme can offer a service which is suitable for the UDH streaming service.

• Ocean and Polar Research
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• v.32 no.4
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• pp.369-377
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• 2010

To characterize ecotoxicological responses to a natural estrogen, $17{\beta}$-estradiol, we evaluated the life-history of the parental ($F_0$) and first generation ($F_1$) of the harpacticoid copepod, Tigriopus japonicus sensu lato. We evaluated the survival of nauplii and copepodites, the number of days until the emergence of copepodites and adult males, the sex ratio, brooding success, and the first brooding day of adult females. No significant differences in the survival rate were noted in response to treatments with different concentrations of $17{\beta}$-estradiol. However, $17{\beta}$-estradiol induced developmental delay and skewed the sex ratio toward males. Copepod development was delayed significantly in the 0.1 and $1\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment groups relative to the control group, with a more pronounced delay in the $F_1$ group. Body length and biomass were significantly smaller in the $17{\beta}$-estradiol treated groups than in the controls. The male emergence of T. japonicus s.l. was very high in the 10 and $30\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment group. Furthermore, exposure to $17{\beta}$-estradiol resulted in morphological deformities such as shrinking and swelling of the urosome, twisted setae of the caudal rami, setal loss of swimming legs, abnormal segmentation of antennules, and dwarfism.

• Korean Journal of Cognitive Science
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• v.30 no.1
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• pp.51-83
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• 2019

Delay of immediate gains/losses brings on additional gaines/losses as much as waiting period. However, there are individual difference in evaluating the value of delayed time discounting on the person. In this study, to investigates the individual differences about valuating the delayed time, it is ascertained the correlation between decisions from intertemporal choice task and individual differences of risk taking/perception, emotion, regulatory focus, and HPSP and BELT, subjective period measuring task. In Addition, it is analyzed the individual differences after classifying good/bad performer of intertemporal tasks and person who perceive long/short about the future periods. As a result, good performers of intertemporal task have high openness and perceive longer about 12 hours, 15 days, 6 months and 5 years. Reconstruction about future temporal length plays an important role on intertemporal task, and it is discussed about necessity of follow up study.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.331-339
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• 1975

This experiment was carried out to obtain some imformations about the ecological variations of the heading time of the newly breeded Indica x Japonica varieties/pedigrees according to the seasonal changes of the seeding date. day length and temperature. The results obtained are summarized as follows; 1) At all varieties. days to heading showed a straight reduction according as the seeding time was delayed. 2) At the group of Japonica varieties. the days to heading of early maturing varieties were much shortened and that of medium or late maturing varieties were little or not shortened under high temperature condition but at the group of Indica ${\times}$ Japonica va rieties/pedigrees. days to heading were significantly elongated under high temerature condition. 3) At the group of Japonica varieties. the effect of the short day condition on the days to heading was significantly high at the medium and the late maturing varieties than at the early maturing varieties. however. the short day effect on the reduction of days to heading was not related with the earlyness of each varieties at the group of Indica ${\times}$ Japonica varieties/pedigrees. 4) Days to heading of all varieties under the high temperature condition were longer than that under the ordinary culture. On the other hand, the days to heading of Japonica varieties under the short day treatment were shorter than the days to heading of ordinary culture but at the group of Indica x Japonica varieties/pedigrees. the days to heading under the short day treatment were longer than ordinary culture. 5) At both varieties groups. the days to heading at each seeding time were significantly correlated with days to heading at ordinary cultivation. fl) At the group of Japonica varieties. relatively high correlation(p=0.1) was recognized between the days to heading by delay of seeding time, but at the group of Indica ${\times}$ Japonicava rieties/pedigrees, correlation between the ordinary heading date and the shortening rate of days to heading was very low.

• Food Science and Preservation
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• v.21 no.6
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• pp.767-775
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• 2014

The shelf-life of fresh mushrooms is notably limited because their browning, texture change, and decay are too fast after immediately harvest. Especially, the best management for extending golden needle mushroom's shelf-life is modified atmosphere packaging under pressure vacuum at cold storage. In this study, three types of films, $20{\mu}m$ polyethylene+polypropylene (PE+PP), oriented polypropylene (OPP), and low density polyethylene (LDPE) were tested to extend the shelf-life of golden needle mushrooms. Mushrooms were packed under pressure vacuum and stored at $10^{\circ}C$ for 2 weeks. The golden mushrooms in LDPE film as a commercial packaging, were highly perishable and immediately proceed deterioration as browning, elongation, fluctuation of respiratory quotient (RQ) and softening within 7 days after packaging. On the other hand, the mushrooms in OPP and PE+PP film shown that shelf-life were extend to 14 days from 7 days, causing delay breakup of vacuum and maintenance of color, length, and RQ during storage. The breakup of vacuum in PE+PP film was faster few days than OPP film packaging. This present study indicated that the golden needle mushrooms by OPP packaging under pressure vacuum treatment might be extended the shelf-life until approximately 14 days during cold storage.

• The Korean Journal of Community Living Science
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• v.15 no.4
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• pp.3-10
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• 2004

The physicochemical and microbiological studies were conducted to examine the effect of Prunus mume extract on the Dongchimi fermentation. Dongchimi with the addition of various levels (0, 0.05, 01, 0.2 or 0.3%) of Prunus mume extract was fermented at $10^{\circ}C$ for 30 days. The pH of the product decreased in the course of fermentation and it was between 3.8~4.2 at 6~8 days fermentation. Total acidity was decreased by the addition of Prunus mume extract. A more rapid decrease in pH and an increase in total acidity were observed in the control Dongchimi than in that with added Prunus mume extract. The content of vitamin C increased for up to 10 days of fermentation and then gradually decreased. Reducing sugar content increased for up to 10 days, and the highest of sugar content was shown in the Dongchimi with 0.3% of added Prunus mume extract. As Prunus mume extract levels increased, the total viable cell number and the Lactobacillus cell number decreased. Dongchitni in which Prunus mume extract was added gained it,j optimum taste after 10 days of fermentation. The results of this study indicate that Prunus mume extract causes a delay in the fermentation of Dongchimi by slowing down pH drop and inhibiting the Lactobacillus cell growth.

• The Korean Journal of Nuclear Medicine
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• v.1 no.1
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• pp.1-19
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• 1967

The effects of X-ray irradiation and the thyroid gland on the erythropoietic system were studied in the white male rabbits. The total body irradiation was done in doses of 250 r and 500 r to each of 5 rabbits for 10days. The factors were 220KV, 10mA, FLI/4 Cu+1 mmAI(HVL:2.0 mm Cu) 50 cm F.S.D. The thyroid dysfunction was experimentally induced, by giving 2mg of thyroid tablets per kg body weight for 15 days in 5 rabbits for hyperthyroidism and by giving 1.5 mC of $^{131}I$ per kg body weight in another 5 rabbits for hypothyroidism. Fourteen healthy rabbits were used as control. The hematologic changes and ferrokinetic data obtained from $^{59}Fe$ and apparent half survival of the red blood cells obtained from $^{51}Cr$ were compared. Following were the results: A. X-ray irradiated group; 1. There were no significant changes in hematologic findings except for leucopenia. A slight decrease of red blood cells was observed in 500 r irradiated animals. 2. The decreases in the iron turnover rates of the plasma and red blood cells as well as in the red cell renewal rate were found in both groups. A :significant decrease of the red cell iron utilization rate was observed in the 500 r irradiated animals. 3. The apparent half survival times of the red blood cells were slightly, in the 250 r ($12.1{\pm}0.80$ days), and markedly shortened in the 500 r irradiated animals ($9.8{\pm}1.38$ days), the normal being $14.0{\pm}1.6$ days. 4. It appears, therefore, that the anemia caused by X-ray irradiation is due to the inhibition of hemopoietic function and the excess destruction of the red blood cells. B. Thyroid dysfunction group; 1. The slight increases of the red blood cell count and circulating blood volume with the normal serum iron level were observed in the hyperthyroid group, while the decreases of the red and white blood cell counts, hemoglobin and hematocrit values with a marked decrease of the serum iron level in the hypothyroid group. 2. A marked decrease of the plasma iron disappearance rate with increases of plasma iron turnover, red cell iron utilization and red cell iron turnover were observed in the hyperthyroid group, while the marked delay and decreases in the hypothyroid group. 3. The apparent half survival times of the red blood cells were almost the same with the control in the hyperthyroid group, ($14.0{\pm}1.58$ while a marked shortening in the hypothyroid group $10.6{\pm}0.30$. 4. It was reconfirmed that the thyroid hormones bear a close relationship with the erythropoietic system, namely, the latter is stimulated by the former. The lack of the thyroid hormones thus induces the bone marrow depression leading to anemia the major cause of which, therefore, is not hemolysis.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.2
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• pp.31-41
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• 1986

Knowledge of the degree of yield reduction due to water stress at different crop growth stages in rice production is important for rational scheduling of irrigation during periods of insufficient water supply. Previous studies to determine the degree of yield reduction duo to water stress suffered from interruptions by rain during experiment. Also the findings did rot relate the degree of water stress to the soil water potential and water deficit status of rice plants. In this study, two years experiments were conducted using the high yielding rice varieties, an Indica x Japonica (Nampoong) and a Japonica variety(Choochung). These were grown in 1/200$^{\circ}$ plastic pots placed under a rainfall autosensing, sliding clear plastic roof facility to control rainfall interruptions. The results obtained were as follows. 1.The two varieties differed in the growth stage most sensitive to water stress as well as the degree of yield reductions. When rice plants were stressed to the leaf rolling score 4 and soil water potential of about - 20 bar at major crop growth stages which included heading, booting, non-effective tillering, panicle initiation and early tillering stages, the yield reductions in the Indica x Japonica variety were 58%, 34%, 27%, 22%, and 21%, respectively, whereas in the Japonica vairety they were 23%, 36%, 1%, 13% and 22%, respectively. This result show that the recommended drainage during non-effective tillering is valid only for the Japonica variety. Sufficient irrigation at booting, heading and early tillering stages are necessary for both varieties. 2.The two varieties showed visible wilting symptoms when the soil water potential dropped to about - 3.0 bar. The Japonica variety showed more leaf rolling than the Indica X Japonica. However, it had a higher retention of leaf water content and greater stomatal diffusive resistance. When the soil water potential dropped, the Japonica variety showed leaf rolling score (LRS) 1 at 0 soil-5. 0 bar and LRS 2 at 0 soil -6.0 bar while the Indica X Japonica showed LRS 1 at 0 soil - 5.5 bar and LRS 2at 0 Soil - 9.0 bar. The stomatal diffusive resistance was maximum at the second top leaf blade in both varieties at intermediate water stress of 0 soil - 4.5 bar. 3.The number of days that was required for the soil water potential to drop to-3. 0 bar and to - 20.0 bar after drainage of irrigation water from the 20cm deep silty clay loam soil in the pots were 6 and 13 days, respectively for booting stage, and 7 and 11 days, respectively for heading stage, 9 and 12 days, respectively for panicle initiation stage, and 12 and 19 days, respectively for early tillering stage. 4.Water stress during the early tillering stage recorded the longest delay in beading time, the largest reduction in panicle numbers and a substantial yield decrease of 20%. This calls for better water management to ensure the availability of water at this stage, particularly during drought periods. In addition, a reexamination of the conventional inter-drainage practice during the non-effective tillering stage is necessary for the high yielding Indica X Japonica varieties.