• Journal of Sensor Science and Technology
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• v.8 no.2
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• pp.139-147
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• 1999

In this paper, we present the new angular velocity pick-off method for DTG (dynamically tuned gyroscope) which is widely used in various inertial navigation systems and motion control systems. In case of the external angular velocity input, the proposed scheme can make a smaller tilt-angle rather than that of conventional PI method in the transient and steady state because it has an additional inner rebalance loop with a mathematical model of the real gyroscope. So, without any mechanical redesign of the DTG, its dynamic range can be enlarged by the proposed method. The theoretical analysis and simulation model of DTG with the proposed scheme are given. Finally, the proposed scheme is verified.

• Journal of Sericultural and Entomological Science
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• v.16 no.1
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• pp.49-55
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• 1974

Studies on the harvest methods for the branch-rearing in autumn are as follows. (1) It turned out to be the best method in the early autumn to thin one to two of the normal branches or the dwarf ones, or pick off some of leaves for the yields, according to the rearing scale. (2) For the rearing of the silkworm larvae at 4th instar, it is recommendable to apply one of the following harvest methods, such as the thinning of dwarf branches, the thinning of some branches, intermediate cutting, and the pick-of of the leaves at low part of mulberry in the regards io the quality of leaves and the labour conditions, and no effects on the harvest. (3) For the rearing of the larvae at 5th instar, it is most practical to adapt one of the yield methods which can produce good harvest with less labours. That is, the pruning. of the middle branches should be gradually made from a part of the mulberry fold. (4) When it is carried out to pick of the leaves on the branches which was left after the middle-pruning harvest in autumn or late, easy and less labours' harvest method of rough picking may be applied in the both of the mulberry pruned in summer or autumn.

• Korean Journal of Veterinary Research
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• v.39 no.6
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• pp.1210-1217
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• 1999

This study was carried out to develop a newly designed ovum pick-up(OPU) instrument for ultrasound-guided transvaginal follicular aspiration in cows. This new instrument consists of out- & inner-layer stainless pipes and a grip with a trigger(hand) switch. Some gauge types of disposable needles and tubes can be attached to this inner pipe. With this instrument, while grasping an ovary with one hand, the other hand can handle in apiration and vacuum on/off with the least assitant's help. With this instrument the mean recovery rate of bovine follicular oocytes was 45.2%. In recovered oocytes, usable oocytes(Grade I & II) were 30.4% and this rate meant 1.4 oocytes per ovary. For 30 days after initial aspiration with this instrument, some adverse effects such as adhesion, hemorrhage, hematoma and other mass formation in/with ovaries were also examined by rectal examination, ultrasonographic and endoscopic images. Adhesion was found in one ovary 1 week after aspiration, and hemorrhagic lesion was found 1-2 days and petechia were found 3-5 days after aspiration and there was no remarkable adverse effects. It was found that this instrument could be applicable and safe for ovum pick-up in cows.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.1
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• pp.26-34
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• 2010

Effects of drying condition (IR radiation) on the optical properties and the printability of coated paper were elucidated at various latex sizes and low and high coating color concentrations. It was found that the smaller latex provided better rheology and higher dry and wet pick strength than the larger one. The high solids coating resulted in higher paper gloss and smaller roughness than the low solids coating, even though the clay addition was reduced by 20 parts in the high solids coating. Increasing IR radiation prohibited binder migration into the base paper. Thus it improved binder distribution and decreased pores in the coated layer, resulting in the increased dry and wet pick strength and the improved printing gloss. On the other hand, the color trapping and ink set-off was impaired with increasing IR radiation. Print mottle index passed through a maximum with increasing IR radiation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.1
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• pp.22-29
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• 2002

The coated paper was greatly affected by the basic physical properties of the binder as well as the amount of the coating formula. High glass transition temperature (Tg) of the styrene-butadiene (SB) latex, selected as the binder in our study, gave the high stiffness to the coated paper, but lowered the binding force and print gloss. The average particle size of the SB latex also greatly affected to the coated paper so that the smaller particle size improved the rheological property of the coating formula and increased the binding force and print gloss. Another property of the SBR latex, gel content, was important because when its value was small, the latex was easily deformed at the high temperature and increased air permeability to the coated paper. Therefore, the lower gel content consequently resulted in the higher blistering resistance, especially in the web paper. The larger portion of the SB latex in the coated formula improved the binding force and print gloss, but decreased the ink set-off and ink-trapping to the coated paper. The heavier coating improved optical properties such as opacity, paper gloss and paper smoothness, to the coated paper.

• IE interfaces
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• v.10 no.1
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• pp.155-167
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• 1997

The purpose of this study is to develop the program for efficient operation of a multi-functional surface mounting device(SMD) which mount various components on a printed circuit board(PCB). These components are provided by diverse types of feeders such as cassette, stick and tray feeders. The SMD has one or two heads. In the SMD, the positions of PCB and feeders and fixed, and the head moves to pick up a component from a feeder and to mount it on the PCB. The number of lanes occupied by each feeder and the nozzle used for each component can be different. We develop an off-line program to minimize the cycle-time of the SMD by studying the optimal assignment of feeders and the optimal mounting sequence of components. Graphical User Interface(GUI) is also developed. Additionally, we consider the line balancing problem which appears when two SMDs are used sequentially.

• IE interfaces
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• v.10 no.1
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• pp.57-65
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• 1997

Less researches on AGV(Automated Guided Vehicle) path configurations have been conducted so far while more studies have been placed in determining AGV guide path directions and pick-up/drop-off station locations, and routing/dispatching/scheduling strategies. In practice plenty of concerns fall in preventing deadlock and simplifying AGV system control through an appropriate AGV path configuration. In order to meet those requirements, a new AGV path configuration, inter-loop stocker type is introduced here. The stocker serves as relaying material between loops as well as stocking material. Automated material handling systems using AGVs play an important role in semiconductor industry including TFT LCD and memory/non-memory chip. A practical example of implementing the inter-loop stocker concept successfully in the TFT LCD fab is presented in this paper.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.2
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• pp.25-40
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• 1997

This research was carried out to investigated the effect of base paper and latex binder on printability and obtical properties of coated paper. Especially, it examined the effect of th pH of vase paper surface and functional groups of latices on the interactions between coating color components and on the structure of coated layer. It was found that the behavior of coating color containing amphoeric latex depends on the pH in the boundary region between coating color and base paper. Thus, the coating color formulated with amphoteric latex formed bulky coating layer by inducing stronger interaction between paper surface and coating components than the coating color with anionic latex. The coated paper with amphoteric latex showed better optical properties (i.e.gloss and optical) and printability (i.e. ink receptivity, wet ink receptivity, and ink set off) than the conventional anionic latex in the acidic and alkaline paper. However, dry pick strength of the coated paper was less decreased. This result indicated that amphoteric latex could also be applied practically to the alkaline paper.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.3
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• pp.87-94
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• 1997

As the paper market becomes more and more competitive, more mills will want to switch to alkaline papermaking to take advantage of the Vowing demand. Many papermakers have tried to do this without success in the past much like the American papermakers did in the late 1970's. The Problem is that runnability Problems occur, drainage slows, Presses pick drying becomes more difficult and sheet quality suffers as a result Sheet holes and breaks occur, and runnability becomes a real operating problem. Converting to alkaline papermaking is not as simple as turning off the alum. We must be aware of the numerous factions that alum served at acid pH and provide alkaline alternatives. It is the purpose of this paper to discuss methods of deposit control via charge neutralization and system control at alkaline pH. This article explains the concept as well as the measurement and control. The resultant benefits are seen in runnability, quality and profitability for the papermaker.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.2 s.120
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• pp.25-30
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• 2007

Recently the use of web offset printing has been increasing, which can provide high print speed, mass production, and high print quality. However, high speed web offset printing has frequently undergone a blistering problem when the printed paper passes through hot air dryers. Blistering occurs in the middle of the base paper or in the coating layer. This paper focused on the blistering occurring in the base paper. In order to elucidate the effect of pigment ratio on blistering, 6 types of coating color were prepared with varying GCC/clay ratios and printability and blistering were investigated focusing on structure changes in the coating layer. When the clay content in the coating layer was increased, surface roughness and surface strength were decreased and paper gloss was increased. In addition, it was found that the coating layer structure with high clay content, which contains lots of discontinuous pores, hindered water vapors to penetrate out and, as a result, blistering occurred.