• Wind and Structures
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• v.9 no.4
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• pp.255-270
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• 2006

Several analytical procedures available in literature, for the evaluation of wind induced fatigue damage of structures, either assume the wide band random stress variations as narrow band random process or use correction factors along with narrow band assumption. This paper compares the correction factors obtained using the Rainflow Cycle (RFC) counting of the measured stress time histories on a lamp mast and a lattice tower, with those evaluated using different frequency domain methods available in literature. A Bi-modal spectral method has been formulated by idealising the single spectral moment method into two modes of background and resonant components, as considered in the gust response factor, for the evaluation of fatigue of slender structures subjected to "along-wind vibrations". A closed form approximation for the effective frequency of the background component has been developed. The simplicity and the accuracy of the new method have been illustrated through a case study by simulating stress time histories at the base of an urban light pole for different mean wind speeds. The correction factors obtained by the Bi-modal spectral method have been compared with those obtained from the simulated stress time histories using RFC counting method. The developed Bi-modal method is observed to be a simple and easy to use alternative to detailed time and frequency domain fatigue analyses without considerable computational and experimental efforts.

• Journal of Ginseng Research
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• v.6 no.1
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• pp.84-99
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• 1982

Water content and its seasonal change in reprodltctive organs were reviewed in relation to cultivation practice s. Precipitati on and humidity under shade roof were reviewed in relation to shading ,jystem and environmental factors. High water content of reproductive organs suggests vulnerability to water stress during reproductive growth stage. Watering during dehisconce treat menu seems to keep optimum temperature but cnoventional practice seems to be too often In watering. Information effe on water physiology of seeds is too rare to develop seed storing method and ctive seed use. Dehiscent mechanism was considered in terms of water absorption of embryo. Precipitation rate of conventional shade roof reaclled to 38% and at line level 50% and varied with shade patterns. Precipitation rate under shade has been investigated for itself but should be investigated in relation to light intensity and soil moisture content Relative humidity under shade depends mainly on air humidity and soil moisture, considerably on shade materials and lithe on pole height, bed width or plant density. Since relative humidity was lower in afternoon it was often less than 50% even in summer with high temperature suggesting possible disorder of phi biological function especially in photosynthesis. More information was needed on optimum humidity for productive physiological function of leaf.

• Journal of Auto-vehicle Safety Association
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• v.9 no.3
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• pp.24-30
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• 2017

This paper presents the development of laser scanner based static obstacle detection algorithm for vehicle localization on lane lost section. On urban autonomous driving, vehicle localization is based on lane information, GPS and digital map is required to ensure. However, in actual urban roads, the lane data may not come in due to traffic jams, intersections, weather conditions, faint lanes and so on. For lane lost section, lane based localization is limited or impossible. The proposed algorithm is designed to determine the lane existence by using reliability of front vision data and can be utilized on lane lost section. For the localization, the laser scanner is used to distinguish the static object through estimation and fusion process based on the speed information on radar data. Then, the laser scanner data are clustered to determine if the object is a static obstacle such as a fence, pole, curb and traffic light. The road boundary is extracted and localization is performed to determine the location of the ego vehicle by comparing with digital map by detection algorithm. It is shown that the localization using the proposed algorithm can contribute effectively to safe autonomous driving.

• Applied Microscopy
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• v.27 no.4
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• pp.417-432
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• 1997

The structures of the fertilized egg envelope in three species of cichlidae, golden severum (Cichlasoma severum var.), convic cichlid (Cichlasoma nigrofasciatum) and discus (Symphysodon aequifasciatus) were investigated by routine light and electron microscopies. The fertilized eggs of all three species were of the non-transparent, ellipsoidal, adhesive and non-floted type. The egg envelopes have a single micropyle, which is thought to the pathway of sperm in the area of the animal pole. In golden severum, an outer surface of egg envelope was covered by a reticular layer, that of convic cichlid was covered by an amorphous reticular layer and that of discus was covered by a branched reticular layer. The fertilized egg envelopes consisted of two distinct layers, an adhesive outer layer and an inner layer, consisted of lamellae alternating with interlamellae of lower electron density, in all three species; an inner layer of golden severum was $15\sim17$ layers, that of convic cichlid was $14\sim16$ layers, and that of discus was $18\sim19$ layers.

• Journal of the Korean Magnetics Society
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• v.2 no.2
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• pp.163-168
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• 1992

Results of magnetic measurement of a prototype Storage Ring dipole magnet for the Pohang Light Source (PLS) are summarized. Hall probe mapping and rotating coil methods are used to measure field profiles and integrated field properties. End chamfering experiments are performed on the as-built magnet, which has four removable pole-end pieces, to meet the specifications set from beam dy-namics requirement. The corrected magnet has efficiency of 99.7% at 2.0 GeV excitation ad higher order multipole error levels less than the specifications for all excitations, showing that the magnet has appropriate properties for the PLS Storage Ring.

• Applied Microscopy
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• v.28 no.2
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• pp.237-253
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• 1998

The structures of the fertilizedegg envelope in threespecies of cyprinidae, leoparddanio (Brachydanio frankei), cherry barb (Barbustitteya) and white cloudmountain fish (Tanichthys albonubes) were investigated by light and electron microscopy. The fertilized eggs of all three species have colorless, transparent, spherical and non-floted type. The egg envelopes have a single micropylewhich is thought to the pathway of sperm in the area of the animal pole. Also, an outer layersof both cherry barband white cloud mountain fish areadhesive types, but in that of leoparddanio has non-adhesivetype. In leopard danio, an outer surface ofegg envelope is covered by mushroom-likestructure, that of cherry barb is arranged by button-like structure, and that of white cloud mountain fish isarranged by rod-likestructure. Inboth leopard danioand cherrybarb, the eggenvelopes consist of three distinct layers; an outer layer, a middle layer and an inner layer, and that of white cloud mountain fish hastwo layers. An innerlayer of egg envelopein leopard danio consist of 10 layers, cherry barb has 8 layers, and white cloud mountain fish has $5\sim6$ layers.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.908-911
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• 1993

The single-Phase induction motor is widely used in many light duty applications. especially in home and the office. At present, many applications which use these motor require continuously adjustable speed control. In the general, the speed control of single-phase induction motor is accomplished at a few discrete speeds by using tapped-windings, pole switching or gear. These techniques is inefficient and complicated. In this paper, auxiliary winding voltage phase angle of single-phase induction motor is used to continuously adjust electromagnetic torque. The analysis includes the determination of the relationship between the auauxiliary winding voltage phase angle and torque. Simulation results of the motor's torque-speed characteristics using the controlled auxiliary winding supply are shown and discussed. The drive is tested using a dynamometer to experimentally verify the results of the theory and simulations.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.62.2-62.2
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• 2019

The ADF-S (AKARI Deep Field - South) toward South Ecliptic Pole is one of the deep survey fields designed for the study of Extragalactic Background Light (EBL). The deep extragalactic survey was initiated by AKARI far-infrared deep observations. Other space missions (e.g., Euclid, NISS, SPHEREx) will perform the deep observations in the ADF-S. Based upon the recent optical survey with KMTNet, we can identify the optical counterparts for dusty star-forming galaxies such as ULIRG, DOG, SMG. Among them, the Dust-Obscured Galaxies (hereafter DOGs with f(24um)/f(R) > 1,000) in the heavily obscured system are expected to play an important role in the formation of most massive galaxies. We have newly discovered ~100 DOGs in ~12 sq. deg. of the ADF-S from our optical survey with KMTNet. We also confirmed that some of DOGs host the most luminous AGN for their black hole masses through the near-infrared spectroscopic follow-ups. Here, we report the properties of high-z hyperluminous DOGs in the ADF-S.

• Korean Journal of Plant Taxonomy
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• v.49 no.2
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• pp.101-106
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• 2019

A pollen morphological study was conducted using light and scanning electron microscopy involving six species belonging to the subtribe Neoguillauminiinae. Pollen samples from the six species are tricolporate, and the colpi are surrounded by broad margo, with the widest width in the equator, narrower toward the pole, and rounded at the end. Based on the pollen morphology, pollen of the species in the subtribe Neoguillauminiinae were divided into four types: the Neoguillauminia type (T1), the C. collinus type (T2), the C. casuarinoides type (T3) and the C. paucifolius type (T4). The generic divergence between Neoguillauminia and Calycopeplus was supported by the pollen characters of the size, amb and lumina shape. In particular, the traits of rounded shape in the outline of the polar view and circular lumina, which appear only in the pollen grains of N. cleopatra, support the recognition of Neoguillauminia as a monotypic genus. Calycopeplus oligandrus and C. paucifolius had the same reticulate pattern of pollen grains, supporting Forster's hypothesis that these two species are closely related. On the other hand, the close relationship between the morphologically similar C. collinus and C. casuarinoides was not supported by the pollen characters. Within the subtribe there are two equally parsimonious hypotheses regarding the evolution of exine characters. The first consists of two changes of microreticulate through parallel evolution from the primitive reticulate exine, and the second is that the microreticulate pattern is differentiated from the reticulate state and then reversed to reticulate pollen grains.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.48.1-48.1
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• 2021

The Main-belt asteroid (298) Baptistina (hereafter 'Baptistina') is regarded as an X- (or C-) type asteroid and the largest member of the Baptistina asteroid family. Its basic physical properties play an important role in understanding the rotational evolution and orbital dynamics of the Baptistina family. In this study, we determined the physical characteristics of Baptistina from the optical observations. We conducted BVRI and R band photometric observations from 2017 to 2021 for a total of 47 nights using the 0.5 - 2.0 m-class telescopes. As a result, the color indices of Baptistina were derived as, , and ; this result is consistent with the previous classification of Baptistina as an X- (or C-) type. We also determined absolute magnitude () and slope parameter () by using a simplified version of the IAU H & G function (Bowell et al. 1989) are mag and respectively. We calculated the effective radius of Baptistina of km considering the visual geometric albedo of 0.131 from the NEOWISE data. Using the light-curve inversion method, the sidereal rotation period of 16.224235 h and the 3D shape model with a pole orientation (,) were also determined. In this presentation we will introduce our observations and results, and also discuss about the physical properties of Baptistina asteroid family members such as color indices.