• The Plant Pathology Journal
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• v.23 no.2
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• pp.103-105
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• 2007

Mechanical transmission of barley seedlings with barley yellow mosaic virus (BaYMV) is generally inefficient and is the major constraint for testing cultivar resistance to the virus. To explore mechanical transmission, BaYMV-infected barley plants were grown at different conditions and used as inoculum sources to seedlings of susceptible barley cultivar Baegdong. Extracts prepared from BaYMV-infected Baegdong plants at 47, 53, 74, and 90 days after symptom appearance (DASA) and grown at 10 and $12^{\circ}C$ gave 10, 30, 68 and 76% infection, respectively on inoculated susceptible barley cv. Baegdong seedlings. While Jinyangbori, another susceptible cultivar obtained 95% infection rate inoculated with extracts from 90 DASA disease source and grown at $10/12^{\circ}C$. However, low infection rates were obtained when the virus sources were grown in a greenhouse at $15-18^{\circ}C$. Our results indicate that longer incubation period and lower temperature are required for virus accumulation and stability.

• Proceedings of the KIEE Conference
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• summer
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• pp.619-621
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• 2004

This paper presents the rapid and accurate algorithm for fault discrimination in transmission lines. When faults occur in transmission lines, fault discrimination is very important. If high impedance faults occur in transmission lines, it cannot be detected by overcurrent relays. The method using current and voltage cannot discriminate high impedance fault. Because of this reason this paper uses voltage and zero sequence current, and the proposed algorithm uses fuzzy logic method. This algorithm uses voltage and zero sequence current per period in case of faults. Single line ground fault and three-phase fault can be detective using voltage. Two-line ground fault and line to line fault and high impedance can be detected using zero sequence current. To prove the performance of the algorithm, it test algorithm with signal obtained from ATPDraw simulation.

• Journal of Power System Engineering
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• v.6 no.2
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• pp.73-81
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• 2002

In this study, electronically controlled automatic transmission adopted on a subcompact model in the market was modelled, and the driving performances of the transmission were simulated with the models. Kinetic and dynamic models of working components are established. The driving simulation program is developed with those models, and the various driving conditions are analyzed. With the results, the dynamic behaviour of the engine and the automatic transmission is easily understood. Especially, the transient performances of torque converter and clutches are deeply analyzed. Skipping the vehicle road test by using this analyzing tool, we can expect the cost down and the reduction of the development period of automatic transmission.

• Journal of information and communication convergence engineering
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• v.8 no.2
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• pp.223-227
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• 2010

In this paper, we present a QoS-aware MAC protocol (QA-MAC) for cluster based wireless sensor networks (WSNs). QA-MAC is a TDMA-based scheduling protocol that minimizes the energy consumption in multi-hop WSNs and provides Quality of Service (QoS). A dynamic scheduling algorithm according to the number of member nodes, node traffics, and traffic priorities is suggested. The selected cluster head allocates time slots for all member nodes in the first TDMA schedule period of each round. During the second schedule period in each round, the cluster head makes a schedule for all data transmission. The proposed QA-MAC (QoS-Aware MAC) could save energy, reduce transmission delay, and support QoS.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.481-484
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• 2002

In every cancer early detection and early treatment is the best way to decrease mortality of patients. Moreover early detection of breast cancer increases the possibility of breast conservation treatment. Although mammography is the most powerful modality for early detection, it is hazardous to be used for young women due to X-ray exposure. Another modality of image diagnosis is ultrasound echo technique. But it is not so powerful to detect breast cancer compared to mammography. Palpation is another modality, but is largely dependent on the skill and experience of medical doctors. A new technique is tested its validity in phantom experiments with good results.

• Korean Journal of Optics and Photonics
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• v.12 no.6
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• pp.485-488
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• 2001

The transmission spectra, the wavelength tunability. and the polarization characteristics of mechanically induced long-period fiber gratings (LPFG's) are investigated experimentally and analyzed theoretically. The transmission and mode coupling characteristics of the fabricated LPFG's agree well with the theoretical results. The resonant wavelengths at which the mode coupling occurs can be tuned over 180 nm and the peak wavelengths for of oethogonally polarized lights are split by -9 nm.

• Journal of Korean Port Research
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• v.8 no.1
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• pp.31-40
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• 1994

Experimental study is carried out to verify the advantages of an air chamber structure in controlling the wave transformation and its dynamic responses. The open, cross and vertical mooring systems are employed in experiments to investigate the variations of wave transmission ratio, natural period of the structures and tensile force acting on the mooring line according to the change of the initial air depth inside the air chamber structure. Experimental results show that the air chamber floating structure expresses the smaller wave transmission ratio and tensile force acting on the mooring line than general one without air chamber, expecially in the long period region of incident wave. Therefore, it is concluded that the air chamber structure suggested in this study can play good roles as a wave controlling castal structure, and a substitute structure of a general floating structure.

• Korean Journal of Materials Research
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• v.19 no.8
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• pp.447-451
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• 2009

The long-period stacking order (LPSO) structures and stacking faults (SFs) in rapidly solidified powder metallurgy (RS P/M) $Mg_{97}Zn_1Y_2$ alloy were investigated by high resolution transmission electron microscopy (HRTEM) observations. The 18R-type LPSO structure with a stacking sequence of ACBCBCBACACACBABAB and a period of 4.86 nm was observed in the as-extruded RS P/M $Mg_{97}Zn_1Y_2$ alloy. After annealing at 773 K for 5 hr, the 18R-type LPSO structure was transformed to the 14H-type LPSO structure with a stacking sequence of ABABABACBCBCBC and a period of 3.64 nm. The 24R-type LPSO structure containing 24 atomic layers of ABABABABCACACACABCBCBCBC with period of 6.18 nm coexists with the 14H-type LPSO structure in the same grains. The LPSO structures contain intrinsic Type II SFs such as BCB/CABA and ABA/CBCB stacking sequences of a closely packed plane.

• Acta Via Serica
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• v.7 no.1
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• pp.53-82
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• 2022

The Hebrew word for silk, meshi, is mentioned in the Bible only once and there is a possibility that the item to which it referred was made of local wild silk. Although Jewish historical sources from the Roman and Byzantine periods mention silk many times, only a few silk textiles have been discovered at a sited dated to the Byzantine period (4^th-7^th centuries CE). The word "silk" occurs in the New Testament, although only once. A turning point in the history of the Negev (Southern Israel) occurred around 400 CE when it underwent a period of prosperity related to the advent of Christianity and pilgrimage, which enabled the purchase of imported silk textiles. The Early Islamic period (7-8th centuries CE) yielded four (out of 310) silk textiles from Nahal 'Omer on the Spice Routes joining Petra, in the Edom Mountains of modern Jordan, and the mercantile outlets on the Mediterranean Sea, notably Gaza and El Arish. The most important silk textile assemblage in the Southern Levant was found near Jericho at Qarantal Cave 38 and dates to the medieval period (9th-13th centuries CE). Linen textiles decorated with silk tapestry originating in Egypt date back to the 10-11th centuries CE. Mulham textiles - silk warp with hidden cotton wefts - were discovered in the medieval fortress on Jazirat Fara'un (Coral Island) in the Red Sea, 14 kilometers south of Elat and today located in Egypt. Mulham is mentioned in literary sources of the ninth century in Iraq and Iran, whence it spread through the Islamic world. The article will present aspects of the origin, transmission, and exchange of these textiles.

• Proceedings of the KIEE Conference
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• summer
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• pp.497-499
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• 2004

Due to a typhoon named MAEMI on Sep12, 2004, 7 transmission towers collapsed and 3 were damaged in the Gyeongnam and Busan areas. These caused long-term black-outs in Goeje-do. When a transmission tower collapses or is damaged, Construction will take more than 2 months and this will be accompanied by long-term black-outs. Therefore a temporary iron pole is used in such emergencies. Current temporary rehabilitation angle steel iron Pole consistes of around 800 members, 2,800 bolts and it takes about 5 days to construct a temporary transmission line. Consiquently wide black-outs occur during the construction of the temporary transmission line. To reduce black-out time, the construction period must be reduced as much as possible. This paper presents new methods to reduce temporary transmission line construction time to within 48 hours by applying a self-reliance assembling method instead of the current man power assembling method and by modulizing each angle steel with duralumin.