• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.196-202
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• 2014

In order to select superior trees based on fruit characteristics and provide basic informations necessary for their improvement, total 107 individual trees of Sorbus alnifolia (Sieb. et Zucc.) K. Koch were selected from 11 wild populations in South Korea. After collecting normal fruit branch, we investigated morphological characteristics of fruit and then considered its relationship among the 11 populations by multivariate analysis method. Results from principal compound analysis showed that it represented 85.8% accumulated explanation from five principal compounds. According to cluster analysis based on fruit characteristics, the natural S. alnifolia populations were classified into four groups and Mt. Mani population was different from other populations. Selection effect with outstanding candidate trees including superior 5 individual trees (Gwangyo 1, Gwangyo 2, Deogyu 7, Mani 29, Mani 30) was estimated at 122.8%, 115.5% and 182.7% in fruit width, length and yield per fruit bunch, respectively. The object of this results will give us invaluable information about breeding by selection of S. alnifolia in south Korea.

• The Korean Journal of Mycology
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• v.49 no.1
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• pp.57-66
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• 2021

Six strains among the shiitake varieties developed by the National Institute of Forest Science were used to select suitable varieties for sawdust block cultivation method. After 100 days cultivation (60 days in dark and 40 days in light), the weight loss rate of the sawdust block media was 14.4% (12.8% to 15.7%) in average. After 5 to 7 days of fruiting process, 2~36 primordia per medium were formed. The number of primordium formation was in the following order: Manchuhyang> Sansanhyang> Sanbaekhyang> Bambithyang> Sangjanghyang> Taehyanggo. The stipe length was 41~59 mm as followed by Taehyanggo (59 mm), Sanbackhyang (56 mm), Bambithyang (54 mm), Manchuhyang (53 mm), Sanjanghyang (45 mm) and Sansanhyang (41 mm). Among the strains, Sansanhyang had short and thick stipe. The average weight of fruiting bodies was 33~77 g as following order of Taehyanggo (77 g), Bambithyang (51 g), Sansanhyang (50 g), Manchuhyang (41 g), Sanjanghyang (34 g) and Sanbackhyang (33 g). Mushroom production per 2 kg medium was the highest in Sanbackhyang (473 g) followed by Bambithyang (287 g), Manchuhyang (175 g), Sansanhyang (109 g), Sanjanghyang (78 g) and Taehyanggo (60 g). The hardness of the cap was 1,218 to 1,839 g/10 mm. Taehyanggo was the hardest (1,839 g/10 mm) and Bambithyang was the softest (1,218 g/10 mm). In conclusion, in the cultivation condition of sawdust block medium, mushroom production was good in Sanbackhyang and Bambithyang. Sansanhyang showed good in terms of fruiting body shape.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.8-13
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• 2011

This study was carried out to investigate the change of photosynthesis, leaf and fruit according to crown layers in Actinidia arguta and hybrid kiwi. Photosynthesis rate (PPFD $1,000{\mu}mol{\cdot}m^{-2}s^{-1}$) were 5.82, 7.11, $9.54{\mu}mol\;CO_2\;m^{-2}s^{-1}$ at lower, middle, and upper position, respectively in 3 layer cultivation type. The length and area of leaves collected from lower position have lager value than upper position. The fruit quality of A. arguta and hybrid kiwifruit increased with increasing crown height. A linear correlation ($R^2=0.72$, 0.89 and 0.98) was shown between fruit weight (Boeun 4, Injea 16 and HM3) and the height of crown layer(layer 1, 2, and 3). From the results, we can suppose that the tree of the upper position of crown layer in the cultivation of A. arguta and hybrid kiwifruit produce high quality fruit due to its high photosynthesis ability.

• Steel and Composite Structures
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• v.23 no.5
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• pp.501-516
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• 2017

Numerical simulations are prevalently used to evaluate the seismic behaviour of structures. The accuracy of the simulation results depends directly on the accuracy of the modelling techniques employed to simulate the behaviour of individual structural members. An empirical modelling technique is employed in this paper to simulate the behaviour of column members under cyclic and seismic loading. Despite the common modelling techniques, this technique is capable of simulating two important aspects of the cyclic and seismic behaviour of columns simultaneously. The proposed fiber-based modelling technique captures explicitly the interaction between the bending moment and the axial force in columns, and the cyclic deterioration of the hysteretic behaviour of these members is implicitly taken into account. The fiber-based model is calibrated based on the cyclic behaviour of square hollow steel sections. The behaviour of several column archetypes is investigated under a dual cyclic loading protocol to develop a benchmark database before the calibration procedure. The dual loading protocol used in this study consists of both axial and lateral loading cycles with varying amplitudes. After the calibration procedure, a regression analysis is conducted to derive an equation for predicting a varying calibrated modelling parameter. Finally, several nonlinear time-history analyses are conducted on a 6-story steel special moment frame in order to investigate how the results of numerical simulations can be affected by employing the intended modelling technique for columns instead of other common modelling techniques.

• Journal of Electrical Engineering and Technology
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• v.3 no.1
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• pp.88-93
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• 2008

The electromagnetic parameters of a permanent magnet synchronous motor (PMSM) such as the open load permanent magnet flux, d axis reactance $X_d$, and q axis reactance $X_q$, are most essential to the performance analysis and optimization design of the motor. Based on the numerical analysis of the 3D electromagnetic field, the three electromagnetic parameters of permanent magnet synchronous motors with U form interior rotor structures are calculated by FEA. The rules of the leakage coefficient and reactance parameters changing with the air gap length, permanent magnet magnetism length, and isolation magnetic bridge dimensions in the rotor are given. The calculated values agree well with the measured values. The FEA results are integrated with the self compiled electromagnetic design program to optimize the prototype motor. The tested performances of the prototype motor prove that the method is suitable for the optimization of motor structure.

• Computers and Concrete
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• v.26 no.3
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• pp.239-255
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• 2020

Experimental and discrete element method were used to investigate the effects of joint number and its angularities on the shear behaviour of joint's bridge area. A new shear test condition was used to model the gypsum cracks under shear loading. Gypsum samples with dimension of 120 mm×100 mm×50 mm were prepared. the length of joints was 2cm. in experimental tests, the joint number is 1, 2 and 3 and its angularities change from 0° to 90° with increment of 45°. Assuming a plane strain condition, special rectangular models are prepared with dimension of 120 mm×100 mm. similar to joints configuration in experimental test, 9 models with different joint number and joint angularities were prepared. This testing show that the failure process is mostly governed by the joint number and joint angularities. The shear strengths of the specimens are related to the fracture pattern and failure mechanism of the discontinuities. The shear behaviour of discontinuities is related to the number of induced tensile cracks which are increased by increasing the rock bridge length. The strength of samples decreases by increasing the joint number and joint angularities. Failure pattern and failure strength are similar in both of the experimental test and numerical simulation.

• Journal of Ginseng Research
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• v.42 no.2
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• pp.208-217
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• 2018

Background: The quality differences in seedlings of medicinal herbs often affect the quality of medicinal parts. The establishment of the grading standard of Panax notoginseng seedlings is significant for the stable quality of medicinal parts of P. notoginseng. Methods: To establish the grading standard of P. notoginseng seedlings, a total of 36,000 P. notoginseng seedlings were collected from 30 producing areas, of which the fresh weight, root length, root diameter, bud length, bud diameter, and rootlet number were measured. The K-means clustering method was applied to grade seedlings and establish the grading standard. Results: The fresh weight and rootlet number of P. notoginseng seedlings were determined as the final indices of grading. P. notoginseng seedlings from different regions of Yunnan could be preliminarily classified into four grades: the special grade, the premium grade, the standard grade, and culled seedlings. Conclusion: The grading standard was proven to be reasonable according to the agronomic characters, emergence rate, and photosynthetic efficiency of seedlings after transplantation, and the yields and contents of active constituents of the medicinal parts from different grades of seedlings.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.4 s.148
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• pp.494-503
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• 2006

Inherent damage zone model is presented to explain the fatigue properties near the fatigue limit and the crack growth threshold consistently Inherent damage zone model assumes that the stress at a point which is located at a small distance, $r_0$, an inherent length of the material that represents the size of effective damage zone, from the crack initiation position governs the fatigue characteristics regardless of the geometric configuration of the specimen; smooth specimen, notched specimen or cracked specimens with short and long crack length. A special feature of the paper is using the exact stress distributions of notched and cracked specimens at the strength evaluations. Analytical elastic solutions by Neuber and Westergaard are employed for this purpose Relationship between fatigue limit of smooth specimen and threshold stress of cracked specimen, occurrence condition of non-propagating crack at the root of elliptic notch and circular hole and relationship between stress concentration factor and fatigue notch factor are discussed quantitatively based on the proposed model.

• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.52-54
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• 2007

Laser wave length can have evaporation effect by absorption because outer skin or tissue of focus is consisted of water almost though absorption of water occurs more than 90% almost in formation thickness of very thin floor. Can operate outer skin, steam by floor and correct incision of formation is available. Suture surgical operation is available to vein or lymph system and surgical operation region can dry and see as eye and radish bleeding surgical operation is available. Specially, stability of tube both end output about pulse by weight very, this research can cause various curative effect because can reduce bulk and control easily current wave style of medical laser using electric power conversion device of high frequency way. If introduce ZVS (Zero Voltage Switching) or ZVZCS (Zero Voltage and Zero Current Switching), is more profitable because can reduce switching damage. Because electric power department of proposed medical laser can do stable soft-switching in wide subordinate extent introducing ZVZCS technique by the first help and control department composes microcontroller, output current waveform user have free form make. Result that experiment because design and manufacture, brought result that improve of 20% than existing equipment, and will be bought to get into superior result if supplement as systematic late.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.111-115
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• 1970

1. Eight Varieties of Nicotiana tabacum, "Yellow special A", "Gold leaf", "Oxford, " "Awha", "Yungzung", "Samsun", "Maruha" and "Hatano" were compared on the photoperiodic responses. 2. Experiments were conducted both under high temp. condition(green-house, average temp $25^{\circ}C$-$35^{\circ}C$) and low temp. condition (out-door; average temp $10^{\circ}C$-$25^{\circ}C$) in four plots of 8.10.12 and 14 hours in day length. 3. The results obtained are summarized as follows; i) In the short day condition, the flowering was accelerated in the low temp. than high. On the contrary, in the high temp, it was accelerated in the long day. ii) Generally speaking, the flowering was responsed more in low temp. and short day length than high temp.-long day. iii) But the above trend was found great difference among varieties..-long day. iii) But the above trend was found great difference among varieties.