• The Plant Pathology Journal
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• v.38 no.4
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• pp.366-371
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• 2022

The white soybean cyst nematode Heterodera sojae, isolated from the roots of soybean in Korea, is widespread in most provinces of the country and has the potential to be as harmful to soybean as H. glycines. Determining the virulence phenotypes of H. sojae is essential to devising management strategies that use resistant cultivars. Consequently, virulence phenotypes of 15 H. sojae populations from Korea were determined on seven soybean lines and one susceptible check variety. Two different HS types were found to be present in Korea; the more common HS type 2.5.7, comprising 73.3% of the H. sojae populations and the less common HS type 0, constituting only 26.7% of the tested populations. Considering the high frequency of H. sojae adaptation to soybean indicator lines, the PI 88788 group may not be a possible source of resistance while PI 548402, PI 90763, PI 437654, and PI 89772 can be used as resistance sources for soybean breeding programs aimed at developing H. sojae-resistant soybean cultivars in Korea.

• Applied Biological Chemistry
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• v.50 no.2
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• pp.87-94
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• 2007

A bacterium which has high enzymatic activities such as amylase, cellulase and protease was isolated from Korean traditional soybean food, doenjang. The isolated bacterium was identified to Bacillus subtilis HS25 by the test of morphological and biochemical properties according to Bergey's Manual of Systematic Bacteriology and API 50 CHL kit, and by the 16S rDNA sequence. The isolated B. subtilis HS25 had a potent antibacterial activity against food born causative or pathogenic bacteria. B. subtilis HS25 is endospore forming cell and contained flagella and abundant viscous material at the out layer of cell wall. It was rod type bacterium $(0.5{\sim}0.8{\times}3{\sim}5{\mu}m)$ having biochemical characteristics such as gram staining(+), catalase(+), oxidase(-) and hydrolysis of esculin(+). The optimal medium compositions for production of antibacterial substance in the B. subtilis HS25 were 1% of soluble starch, 0.5% of yeast extract, 0.5% of peptone and 0.05% of MgCl$_2{\cdot}6H_{2}O$. The optimum temperature and pH of the growth of the B. subtilis HS25 was 35$^{\circ}C$ and pH 7.5, respectively. The antibacterial activity was more high in neutral to a little alkaline pH (6.5-10.5) than in acidic pH. The optimal shaking speed to grow and to produce antibacterial substance of the B. subtilis HS25 was 160${\sim}$200 rpm. The optimal culture time for antibacterial activities of the bacterium were shown to be in the range of 12-36 hr.

• International Journal of Highway Engineering
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• v.14 no.5
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• pp.179-188
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• 2012

PURPOSES: The aim of this study is to analyze overloading control effectiveness of enforcing overweighted vehicles using HS-WIM (High-Speed Weigh-in-Motion) at main lane of expressway. METHODS: To analyze the weight distribution statistically, HS-WIM system should has an appropriate weighing accuracy. Thus, the weighing accuracy of the two HS-WIM systems was estimated by applying European specifications and ASTM (American Standards for Testing and Materials) for WIM in this study. Based on the results of accuracy test, overweight enforcement system has been operated at main lanes of two expressway routes in order to provide weight informations of overweighted vehicle in real time for enforcement squad. To evaluate the overloading control effectiveness with enforcement, traffic volume and axle loads of trucks for two months at the right after beginning of the enforcement were compared with data set for same periods before the enforcement. RESULTS: As the results of weighing accuracy test, both WIM systems were accepted to the most precise type that can be useful to applicate not only statistical purpose but enforcing on overweight vehicles directly. After the enforcement, the rate of overweighted trucks that weighed over enforcement limits had been decreased by 27% compared with the rate before the enforcement. Especially, the rate of overweighted trucks that weighed over 48 tons had been decreased by 91%. On the other hand, in counterpoint to decrease of the overweighted vehicle, the rate of trucks that weighed under enforcement limits had been increased by 7%. CONCLUSIONS: From the results, it is quite clear that overloading has been controlled since the beginning of the enforcement.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.6
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• pp.15-21
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• 1998

Mostly a ride comfort and handling performance of vehicle is influenced by dynamic behavior control of vehicle. We are focusing on development of a semi-intelligent suspension system with continuously variable damper(HS-SH type). only using absolute velocity of sprung mass without using the relative velocity besides having lower system prices and a little energy requirement. In this paper, the system is realized in consideration to control strategy (sky-hook control, hybrid filter, etc.) and has been proved to have improvement of behavior control of vehicle by quarter car and Vehicle test, respectively.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2039-2041
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• 1998

In this paper, Operation characteristics of the active clamp(ACL) zero-voltage-switching(ZVS) forward converter(FC) and active clamp hard- switching(HS) forward converter are compared with respect to loss analysis. The losses of semiconductor (including conduction losses and switching losses), transformer(containing the core loss and copper loss) and parasitic element of passive element (capacitor, inductor) are measured and compared for each type. For an experiment we have built 50W ACL ZVS-FC and ACL HS-FC, in which the switching frequency is 200kHz, and test it. The experimental results show that both types of operation have nearly same characteristics.

• Restorative Dentistry and Endodontics
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• v.33 no.5
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• pp.435-442
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• 2008

Type II root canal was defined that two canals leave the chamber and merge to form a single canal at short of the apex. The aim of this study was to analyse the master apical file (MAF) size according to various instrumentation techniques in the type II root canal when each canal was enlarged to working length. Eighty mesial roots of molar with ISO #15 initial apical file (IAF) size in type II root canals were randomly divided into four experimental groups with 20 teeth each. According to enlarging instruments, four groups are: K-$FLEXOFILE^{(R)}$ (KF), engine-driven Ni-Ti $P_{RO}T_{APER}{^{(R)}}$ (PT), HERO $Shaper^{(R)}$ (HS), $K^{3\;TM}$ (K3). All canals were enlarged to each working length with ISO #30 size: #30 in KF, F3 in PT, .04/30 in HS, and .06/30 in K3. The master apical file (MAF) size was confirmed by tactile sensation and universal test- ing machine (EZ test, Shimadzu Co., Kyoto, Japan). The mean MAF size was statistically compared using one-way ANOVA and Tukey HSD test at the 0.05 probability level. These results show that the MAF size was appeared one or two sizes larger than the final enlarging instrument when all canal in type II configuration were enlarged to each working length. Therefore, the clinician have to confirm the apical stop once more after instrumentation of type II root canal.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.4
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• pp.67-80
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• 2020

High-speed weigh in motion (HS-WIM) is a real-time unmanned system for measuring the weight of a freight-carrying vehicle while it is in motion without controlling vehicle traffic flow or deceleration. In Korea, HS-WIM systems are installed on the national highways and general national ways for pre-selection by law enforcement. In this study, to improve the measurement accuracy of HS-WIM, we devise improvements to the existing integral and peak weight conversion algorithms, and we provide a new fusion algorithm that can be applied to the mat-type HS-WIM. As a result of analyzing vehicle driving tests at a real site, we confirmed the highest level of weight-measuring accuracy.

• Analytical Science and Technology
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• v.20 no.3
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• pp.183-192
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• 2007

The various environmental regulation directives such as RoHS (restriction of hazardous substances in electrical and electronic products) and WEEE (waste from electrical and electronic equipments) are practically used as the technical barrier in international trade (TBT) of vehicles and electrical and electronic products recently. Regarding such an environmental regulation, Korea Research Institute of Standards Science (KRISS) organized a proficiency testing scheme to establish the reliability of measurement results produced by the relevant research institutes and test laboratories in Korea. Participants were 31 laboratories related to production of the electrical and electronic equipments and mobile vehicles. Two polypropylene samples of pellet type were employed as the proficiency testing materials (PTMs). Cadmium and lead were the analytes chosen among six components regulated in European Union (EU) RoHS directive. The PTMs were sent to the participants by post on September $1^{st}$ 2006, and deadline for results submission were October $10^{th}$ 2006. The results of each laboratory were evaluated in comparison with KRISS reference values using Robustic Z-score and Youden plot methods. The results of the various sample digestion methods were also compared. Most of participants reported good agreement within 10 % range of reference values. However, results from several laboratories showed significant biases from reference values. These laboratories should establish the quality assurance system for improvement of the measurement reliability.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.3
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• pp.199-206
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• 2005

As the basic study about improvement of yellow croaker drift gill net fishing implement and development of the fishing system, this study drew problem after synthetically analyzing hauling system of yellow croaker drift gill net used in the coast of Chuja Island and tested several characters and analyzed in hauling process with 5 step net hauler model for improving the problem. The analysis results are as follows. When the angle between axises of drum centers was small, it showed the tendency that hauling time was fast. Hauling time was faster when drum was 5 step rather than 3 step. When drum was 5 step, slippery phenomenon was small and hauling was stable. Tension was larger when drum was 5 step rather than 3 step. When drum was 5 step, the range of change of the maximum and minimum value was small and hauling was stable. When drum was 3 step, there was following formula between hauling time ($Ht_3$) and angle between axises of drum centers ($A_g$) $Ht_3$ : ($7.15Hs^{-0.81}$) $A_g^{-0.81}$, when drum was 5 step there was following formula.$Ht_5$ : ($6.45Hs^{-0.75}$) $A_g0.10$, here, Hs is hauling speed. When drum was 3 step and hauling speed was 28cm/sec, tension was $T=0.08A_8^3-1.60A_g^3-0.49A_g+369.56(r=0.99)$, when drum was 5 step, tension was, $T=-0.01A_g^3+1.96A_g^2-34.05A_g+414.58$ (r-0.99), here, T was tension(g).

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.192-200
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• 2002

Semi-active suspension systems are greatly expected to be in the mainstream of future controlled suspensions for passenger cars. In this study, a continuous variable damper for a passenger car suspension is developed, which is controlled actively and exhibits high performance with light weight, low cost, and low energy consumption. To get fast response of the damper, reverse damping mechanism is adapted, and to get small pressure change rate after blow-off, a pilot controlled proportional valve is designed and analyzed. The reverse continuous variable damper is designed as a HS-SH damper that offers good body control with reduced transferred input force from tire, compared with any other type of suspension system. The damper structure is designed, so that rebound and compression damping force can be tuned independently, of which variable valve is placed externally. The rate of pressure change with respect to the flow rate after blow-off becomes smooth when the fixed orifice size increases, which means that the blow-off slope is controllable using the fixed orifice size. The damping force variance is wide and continuous, and is controlled by the spool opening, of which scheme is usually adapted in proportional valves. The reverse continuous variable damper developed in this study is expected to be utilized in the semi-active suspension systems in passenger cars after its performance and simplicity of the design is confirmed through real car test.