• The Transactions of the Korean Institute of Electrical Engineers
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• v.32 no.6
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• pp.211-218
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• 1983

In this paper, an attempt is made to match the continuous state trajectory of the digital control system with that of its continuous data model. Matching the state trajectories instead of the output responses assures that the performances of the internal variables of the plant as well as the output variables are preserved in the discretization. The mathematical tool used in this research is an extended maximum principle of the Pontryagin type, which enables one to synthesize a staircase type of optimal control signals, such as the output signal of a zero-order hold asociated with a digital controller. A general mathematical expression of the digital controller which may be used to replace the analog controller of a general system while preserving as mauch as possible the performance characteristics of the original continuous-data control system is derived in this paper.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.6
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• pp.927-934
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• 2017

This paper is concerned with applicability of two-degree-of-freedom controllers to the recently suggested i-PID controllers, in which unknown parts of the plant are taken into account without any modeling procedure. First, i-PID controller with two-degree-of-freedom is applied to a specific model, called Anisochronic model, to confirm the usefulness of this method. Second, using the original examples of i-PID controllers, it is confirmed that performance/robustness of system are to be improved due to two-degree-of-freedom, especially when the input changes suddenly. It is seen that as the desired robustness increases the optimal value of two-degree-of-freedom parameter ${\alpha}_A$ would be negative. It is checked and verified that if this value was limited to 1 or less as is generally known, performance would be degraded.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.341-344
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• 2008

In order to study the effect of shot blasting condition on the formability of thin high strength steels, specimens were made by changing line speed of a commercial shot blasting plant with maintaining constant impeller condition. Surface roughness of prepared specimens was multiplied by lowering line speed or increasing density of shot impact. Formability was reduced as increasing shot impact. The elongation and stretching formability of shot blasted sheet were decreased by about 10% compared to original sheet. More significant decrease in bending formability was observed after shot blasting. This might be due to the concentrated impact near the surface where major strain occurs during bending process.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.6 s.171
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• pp.76-82
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• 2005

In this paper, the pole placement controller based on the Robust Internal-loop Compensator (RIC) structure, which has inherent structural equivalence to disturbance observer, is proposed to control a linear positioning system. This controller has the advantage to easily select controller gains by using pole placement without loss of that of original RIC structure. The principal is to construct the pole placement controller for a nominal internal model instead of unknown real plant. Using linear motion experiment showed the effectiveness of the proposed controller.

• Journal of information and communication convergence engineering
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• v.20 no.1
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• pp.65-72
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• 2022

With the mark of the fourth industrial revolution, the smart factory is evolving into a new future manufacturing plant. As a human-machine-interactive tool, augmented reality (AR) helps workers acquire the proficiency needed in smart factories. The valuable data displayed on the AR device must be delivered intuitively to users. Current AR applications used in smart factories lack user movement calibration, and visual fiducial markers for position correction are detected only nearby. This paper demonstrates a marker-based object detection using perspective projection to adjust augmented content while maintaining the user's original perspective with displacement. A new angle, location, and scaling values for the AR content can be calculated by comparing equivalent marker positions in two images. Two experiments were conducted to verify the implementation of the algorithm and its practicality in the smart factory. The markers were well-detected in both experiments, and the applicability in smart factories was verified by presenting appropriate displacement values for AR contents according to various movements.

• 중국학논총
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• no.69
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• pp.121-143
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• 2021

'老' refers to the old man with the characteristics of being aged in the original meaning 'to be aged' (adjective), which is a metonymy of 'substituting the whole with a part'. In combination with nouns, '老' uses a lot of metaphorical expressions that are understood through animals closest to the attributes of people with aged characteristics, plants and objects. '老' can be extended to the meaning of 'the survival time, duration, recognition time, and existence time of a person, animal, plant, or object are long', or 'the survival time is over', which can be said to be a metonymy of 'substituting cause with result'. An experienced target respected by people on a positive level and a target with banal thoughts, habits, nature, and personality on the negative level can also be conceptualized and expressed as '老'.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.201-214
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• 2015

This study was conducted to identify forest topsoil's usefulness from July 2013 to Oct 2014. Generally, there are abundant seeds in topsoils and it can be used at restoration works. Mt. GARIWANG is famous for biodiversity in Korea. This study was aimed to find out the suitable utilization methods of natural topsoils for restoration works at sky-slopes construction sites. Test beds was made to identify suitable collecting times and suitable topsoil thickness. The main results are summarized as follows. First, Mt. GARIWANG have diverse species and in topsoils we can find lots of burried seeds which can be used at restoration works. Second, according to indoor experiment, as the depth of topsoil used thicker, the number of plants and coverage rates were increased. Also, there were no distinct differences in coverage rates between 5cm and 8cm thick topsoil plots and it can be possible to use at least 3cm thick topsoils even thou lower coverage rates. Third, as the results of research about indoor and outdoor experimental plots, there were difference in plant emergency. If we use the stabilizer to protect soil erosion, then we can get more increased results at sloped outdoor experimental plots. Fourth, based on environmental impact assessment, there was 389 species in whole region of Mt. GARIWANG. Through this seed bank experiments, we can find 23 varieties, including 4 tree varieties and 19 herbaceous varieties. We can find lots of native herbaceous species from topsoils. Fifth, this research was done at the specific area of Mt. GARIWANG and used limited topsoils. But we monitoring more longer periods, then there will be more useful outcomes. Finally by researching topsoils of Mt. GARIWANG, we can find diverse native plants. Thus, we must reuse natural topsoils of Mt. Gariwang for restoration of original vegetation.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.437-441
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• 1990

For the genetic development of more powerful antagonistic Pseudomom - YPL-1 as a biocontxol agent against soilborne plant pathogenic Fuaarium solani causing root rot of many important crops, mutants improving the productivity of chitinase were obtained by mutation with UV radiation or NTG treatment, P. stutzeri YPL-M26 (UV mutant) and P. stutzeri YPL-MI78 (NTG mutant) could improve the productivity of chitinase by 2.5 and 2.0 times, and its antifungal activity by 1.7 and 1.5 times, respectively. The antifungal mechanism of P. stutzeri YPL-M26 was caused by lysis of the fungal cell wall by hydrolytic enzymes such as chitinase. The antifungal activity of crude chitinase of P. stutzeri YPLM26 on the mycelial growth of F. solani was observed to be much higher than that of the original strain. The enzymes produced by P. stutzeri YPL-M26 were the same as the original strain in enzymatic properties such as optimal pH and temperature.

• The Korea Journal of Herbology
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• v.26 no.3
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• pp.57-63
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• 2011

Objectives : Peucedani Radix ('Jeonho' in Korean) is the root of Peucedanum praeruptorum or Angelica decursiva. However, the root of Anthriscus sylvestris has usually been distributed as Jeonho. This study was performed to determine the discriminative criteria of Jeonho, focused on distribution in Korean markets. Methods : We have determined identification keys to discriminate each Jeonho samples, through observation of external morphology of original plants, and the research of external and internal morphological features of dried Jeonho herbs. Results : Because of identical to the Korean plant name 'Jeonho', Anthrisci Radix had been came into use as a substitute of Jeonho in Korea during the time of Japanese colonial rule. The original plants of Jeonho and its substitute are discriminated with shape of leaf, leaf margin and color of stem. External morphological features of the medicinal herbs of Jeonho are different in the color of cross-sections, pellucid dot, white powder. Internal morphological points, such as fiber bundle of xylem, seconadary mudullary ray and ray of xylem were also used as discriminative criteria for Jeonho. Further details(e.g. identificaion keys) are in the article. Conclusions : We think that these discriminative criteria will be meaningful in identifying the substitutes and adulterants of Jeonho.

• The Korea Journal of Herbology
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• v.32 no.1
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• pp.41-45
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• 2017

Objectives : The purpose of this study was to assume the origin and daily dose of Allii Chinensis Bulbus in Treatise on Cold Damage Diseases and Prescriptions of the Gold Chamber. Methods : I assumed the origin with Book of Materica Medica such as Illustration and Classic of Materia Medica(本草圖經), Illustration and Consideration of Plant's Name and Reality(植物名實圖考), The Korean Herbal Pharmacopoeia Forth Edition, Annotation of Hangeul Treatise of Cold Damages Diseases, and daily dose based on general principle applied on dose of Treatise on Cold Damage Diseases. Results : In Treatise on Cold Damage Diseases and Prescriptions of the Gold Chamber, the original species of Allii Chinensis Bulbus was Allium chinense G. Don. It was to be measured with weight. It was too big to write on size due to it's 10~30mm length and 3~12mm in diameter. And due to irregular size, it can't be written on number, too. Daily dose of Allii Chinensis Bulbus in Whaeyeok-san(回逆散), Gwalluhaebaekbanha-tang(栝樓薤白半夏湯) was 3 Ryang(兩), which was the most common case in Treatise on Cold Damage Diseases. And that in Gwalluhaebaekgyeji-tang(栝樓薤白桂枝湯), Gwalluhaebaekbaekju-tang(栝樓薤白白酒湯) is 8 Ryang(兩), which was the largest dose as dried herb in Treatise on Cold Damage Diseases Conclusions : The original species of Allii Chinensis Bulbus was Allium chinense G. Don. The daily dose of Allii Chinensis Bulbus was 3 Ryang(兩)(19.5g) in Whaeyeok-san and Gwalluhaebaekbanha-tang, and was 8 Ryang(兩)(52g) in Gwalluhaebaekgyeji-tang and Gwalluhaebaekbaekju-tang.