• Korean Journal of Agricultural Science
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• v.41 no.1
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• pp.29-34
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• 2014

Phytophthora blight occurrence is caused by various environmental factors, and the progress can be regularly predicted so that several predictive models have been developed. The models predict the timing of the disease occurrence, but they do not include the methods of the disease control. Effective fungicide control, control threshold, prediction models were investigated in the study to reflect on customized control modules for the model forecasting the occurrence of Phytophthora blight on hot pepper.

• Journal of Hydrogen and New Energy
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• v.21 no.2
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• pp.98-103
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• 2010

In order to develop two-stroke free-piston hydrogen engine to obtain high thermal efficiency and low emission, backfire occurrence have to be prevented. In this research, backfire characteristics are analyzed as functions of the intake valve opening timing and compression chamber pressure under piston by using RICEM (Rapid Intake Compression Expansion Machine) that has reverse uni-flow scavenging. As the result, reverse uni-flow scavenging is advantage about back fire. but, it exists suitable intake valve opening timing and its timing become known that equivalence ratio 1 retard until the piston rises. Also, To rise chamber pressure of lower piston, this does not cause backfire occurs in equivalent ratio 0.6 observed back fire. Therefore, 2cycle hydrogen fueled free-piston engine is undesirable scavenging compression by compressing the piston.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3311-3316
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• 2007

To analyze the influence of valve overlap period on a backfire occurrence, the single cylinder research engine with MCVVT(Mechanical Continuous Variable Valve Timing) system is developed and backfire limit equivalence ratio defined as fuel-air ratio equivalence ratio at which backfire occurs is examined according to various valve overlap period. The MCVVT is the system to control valve overlap period by mechanical device. It is estimated that the lower valve overlap period has the higher backfire limit equivalence ratio though the same energy is supplied. When the valve overlap period is changed from 30$^{circ}$ CA to 0$^{circ}$ CA, backfire limit equivalence ratio is increased 74%, approximately. It means that valve overlap period is concern in backfire occurrence, and may be one of the methods for controlling back fire occurred in a $H_2$ engine.

• Korean journal of applied entomology
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• v.49 no.3
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• pp.261-264
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• 2010

Occurrences of Rhopalosipnum rufiabdominalis damage in the leaves of Japanese apricots were observed in Hadong, Gyeongnam Province, a major producing area. R. rufiabdominalis occurred from early May to mid October, with the peak occurrence of damaged leaves in mid May. To find proper timing of chemical control against R. rufiabdominalis, acetamiprid WP was sprayed weekly from 3 April, before budbreak, to 8 May in 2007. The best time for control R. rufiabdominalis was on 17 April 2007, at which the leaves were still tender and developing up to 3 to 5 leaves.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.162-166
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• 2011

The distribution and occurrence of Charybdis japonica larvae were investigated off Yeonpyong-do, Korea, in the Yellow Sea. C. japonica larvae were collected monthly at 15 stations from early June to late October in 2006 and 2007. At each station, a Bongo net with 303 and $505{\mu}m$ mesh was deployed once with a double oblique tow. No larvae were caught in June, in both years. Zoea I was predominant in late July in 2006 and early August in 2007, whereas Zoea I accounted for 84% of all larvae collected and no larval stages later than Zoea III were sampled. Megalopa were the most abundant larval stage at all stations in late August in both years. The timing of larval hatching of C. japonica may be related to that of phytoplankton blooms in the study area. The finding that Zoea I and Megalopa were predominant in the study are may indicate that C. charybdis larvae are carried by advection.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.8 s.350
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• pp.35-43
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• 2006

In the paper, we propose a new method for power optimization that uses path balancing based on stochastic estimation of glitch in Statistical Static Timing Analysis (SSTA). The proposed method estimates the probability of glitch occurrence using tightness probability of each node in timing graph. In addition, we propose efficient gate sizing technique for glitch reduction using accurate calculation of sizing effect in delay considering probability of glitch occurrence. The efficiency of proposed method has been verified on ISCAS85 benchmark circuits with $0.16{\mu}m$ model parameters. Experimental results show up to 8.6% of accuracy improvement in glitch estimation and 9.5% of optimization improvement.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.3
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• pp.291-296
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• 2006

In context-aware computing environment, some context is characterized by a single event, but many other contexts are determined by a sequence of events which happen with some timing constraints. Therefore context inference could be conducted by monitoring the sequence of event occurrence along with checking their conformance with timing constraints. Some context could be described with fuzzy concepts instead of concrete concepts. Multiple entities may interact with a service system in the context-aware environments, and thus the context inference mechanism should be equipped to handle multiple entities in the same situation. This paper proposes a context inference model which is based on the so-called fuzzy colored timed Petri net. The model represents and handles the sequential occurrence of some events along with involving timing constraints, deals with the multiple entities using the colored Petri net model, and employs the concept of fuzzy tokens to manage the fuzzy concepts.

• Journal of Animal Science and Technology
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• v.59 no.4
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• pp.7.1-7.13
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• 2017

Background: Selenium is one of the trace minerals whose deficiency is known to lead to complications of female reproduction. The identified gaps in researches regarding selenium and pregnancy include optimizing the dosage of selenium supplementation, timing of supplementation, finding the best form and type of selenium, and selenium administration combined with other antioxidants. Hence, this study was conceptualized to address one of the identified gaps, that is, to find out the best timing of selenium administration around the time of pregnancy. Specifically, this study aimed to assess the effects of maternal Selenium-supplementation, administered at various stages of periconception period, on murine blastocyst morphology, percent occurrence of good quality blastocysts, and implantation status. Methods: ICR female mice were randomly assigned into the unsupplemented group (Group I) receiving basal diet without selenium, and treatment groups given with $3.0{\mu}g$ selenium-supplement per day during pregestation only (Group II), pregestation-throughout-gestation (Group III) and gestation only (Group IV). Both blastocyst morphology and implantation status were assessed. Results: The morphometric measurements of blastocysts appeared to be unaffected by selenium-supplementation at different stages of periconception. Selenium-supplementation at pregestation only (Group II) and gestation only (Group IV) produced higher percent occurrence of good quality blastocysts and lower percent pre-implantation loss than Group III. Among all the treatment groups, Group III (Selenium-supplementation during pregestation-to-gestation) yielded the lowest quality blastocysts and highest percent pre-implantation loss. Conclusion: Maternal selenium-supplementation during pregestation and gestation stages of the periconception period yielded a high percent occurrence of good quality blastocysts and pre-implantation success.

• Journal of the Korean Society for Railway
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• v.9 no.6 s.37
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• pp.657-663
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• 2006

By measuring concrete temperature and strains of concrete and reinforcing bars throughout gages embedded and also by observing the crack occurrence, this study aims at the characteristics of structural behavior of subway wall structure in associate with concrete ages. The length of 23.5m, thickness of 2.0m of real subway custody line was selected as a representative structure and 7 thermocouples and 6 strain gages were installed to measure the behavior of wall structure. The results were compared and verified with analytical results using MIDAS in order to show their usefulness. It was found that only attachment of strain gages on the surface of reinforcing bars can figure out the timing of crack occurrence and hydration heat program is useful to estimate comparatively exact magnitudes of temperature. Since estimated time of crack occurrence throughout thermal stress analysis depends on the period of transferred thermal stress from concrete to reinforcing bars, however, cracks from naked eyes were identified later than analytical results. Cracks were observed first at the center of wall line and then to the end of line symmetrically.

• Journal of Hydrogen and New Energy
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• v.18 no.4
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• pp.374-381
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• 2007

In order to verify the feasibility of expansion of back-fire limit equivalence ratio in the hydrogen-fueled engine with external mixture, the characteristics of performance and combustion are experimentally analyzed with change of intake/exhaust valve timings under the fixed valve overlap period of $0^{\circ}$ CA(non-valve overlap period). These characteristics are also tested for the change of exhaust valve closing timing while intake valve opening timing is fixed to clear the main cause of back-fire occurrence. As the results, the less valve overlap period center is retarded, the more back-fire limit equivalence ratio increases and back-fire does not occurred after TDC. In addition, it was shown that the control of back-fire is dependent on intake valve opening timing than valve overlap period.