• Journal of Korean Society of Rural Planning
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• v.8 no.1 s.15
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• pp.15-25
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• 2002

The study was carried out to investigate the water balance and losses of nutrients from paddy fields during cropping period. The size of paddy fields was 95 ha and the fields were irrigated from a pumping station. The runoff loading was the highest in June because of the high concentrations of nutrients due to applied fertilizer, When the runoff Bosses of nutrients were compared to applied chemical fertilizer, it was found that 39.1 % to 42.5 % of nitrogen lost via runoff while runoff losses of phosphorus account for 14.5 % to 17 % of the total applied amount during cropping period. When the ratio was calculated between nutrients losses by infiltration and the applied of chemical fertilizer, two year results showed 9.1% to 10.8% for nitrogen and 0.5% for phosphorus, respectively.

• Asian Journal of Innovation and Policy
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• v.9 no.3
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• pp.308-338
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• 2020

The entrepreneurial journey is not short of challenges, and about 90% + tech start-ups experience failure (Startup Genome, 2019). The magnitude of the challenges varies across the tech start-up lifecycle stages, namely emergence, stability, and growth. This opens the research question, do the profiles of a start-up and its co-founder impact start-up success or failure across its lifecycle stages? This study aims to understand and identify the profiles of tech start-ups and their co-founders. We gathered primary data from 151 start-ups (Status: 101 failed and 50 successful ones), and they are across different lifecycle stages and represent six major start-up hubs in India. The chi-square test on status and start-up's lifecycle stage indicates a noticeable correlation, and they are not independent. The Kruskal Wallis test was used to distinguish statistically significant profile attributes. The parameters distinguishing success and failure are identified, and the need to deliver customer experience is emphasized by the start-up profile attributes: Product/service, high-tech nature of a start-up, investor fund availed, co-founder experience, and employee count. The importance of entrepreneurial experience is ascertained with entrepreneur profile attributes: Entrepreneurial expertise, the number of prior and current start-ups, their willingness to start again in the event of failure, and age of co-founder, which is a proxy to learning and experience. This study has implications for entrepreneurs, investors, and policymakers.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.59-64
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• 2022

Vibration is one of the factors that degrades the performance of equipment and measurement equipment used in high-tech industries such as semiconductors and display. The vibration isolator is classified into passive type and active type. The passive vibration isolator has the weakness of insufficient vibration isolation performance in the low frequency band, so an active vibration control system that can overcome these problems is used recently. In this paper, PID controller is used to control the active vibration isolator. Methods for setting the gain of the PID controller include the Zeigler-Nichols method, the pole placement method. These methods have the disadvantage of requiring a lot of time or knowing the system model accurately. This paper proposes the gain auto tuning method of the active vibration isolator applied with the PSO algorithm, which is an optimization algorithm that is easy to implement and has stable convergence performance with low calculations. It is expected that it will be possible to improve vibration isolation performance and reduce the time required for gain tuning by applying the proposed PSO algorithm to the active vibration isolator.

• Polymer(Korea)
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• v.39 no.3
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• pp.493-498
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• 2015

For biomaterials for skin regeneration with minimized inflammatory response, high bioactivity and biocompatibility are highly required. Also, it should have a porous microstructure to improve cell adhesion and growth. In this study, we extracted a new collagen source from duck's feet which is by-product, and made the shape of sponges from duck's feet collagen (DC) to compare with DBP and SIS. To analyze physical and chemical property of the scaffold, SEM and FTIR were used. MTT assay was used to measure the attachment and proliferation of NIH/3T3 in the scaffolds. RTPCR was used to evaluate the expression of proinflammatory cytokine. Also, 1,1-diphenyl-2-picrylhydrazyl (DPPH) was used to measure the ability of antioxidant activity. Overall, this study shows that DC scaffold is biocompatible and has good physical property. Additionally, DC scaffold shows the potential as wound healing biomaterials.

• Polymer(Korea)
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• v.35 no.4
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• pp.277-283
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• 2011

Solid dispersion is mainly used for improved dissolution of poorly water-soluble drugs. Solid dispersion of pranlukast was prepared by spray-drying with plasdone S-630. When pH of water was high, pranlukast was highly soluble in the solubility experiment of solid dispersions with varying pH. The particle size of pranlukast particles in solid dispersions was measured to be in nanometers scale based on particle size analysis. Zeta-potential analysis confirmed the negative charge of solid dispersion. SEM was used to observe the surface of solid dispersion, which confirmed spherical morphology, DSC and XRD confirmed the amorphous nature of solid dispersions. The in vitro test was carried out to find improved dissolution rate of pranlukast solid dispersion in simulated juice gastric and a controlled experiment was carried out to compare pranlukast solid dispersions with a conventional drug (Onon$^{(R)}$), These results showed the dissolution properties of pranlukast solid dispersions prepared by spray drying proper for the oral pharmaceutical formulation.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.1
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• pp.42-48
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• 2023

Recently, there has been an increasing demand for performance improvement and miniaturization in response to the growing variety of signals and power demands in many industries such as mobile, IoT, and automotive. As a result, there is a high demand for high-performance chips and advanced packaging technologies that can package such chips. In this context, the FOWLP process technology is a suitable technology, and this paper discusses the plasma application technologies that are being used and studied to improve the shortcomings of this process. The paper is divided into four parts, with an introduction and case studies for each of the plasma application technologies used in each part.

• Journal of Korea Technology Innovation Society
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• v.1 no.2
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• pp.231-244
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• 1998

The purpose of this analysis is to clarify the direction and nature of the future leading industries in Korea. Existing studies were analyzed in depth and their implications are as follows. Existing studies have not given a careful consideration for the structural adjustment of Korean economy and the atmosphere for the growth of prospective leading industries. In relation to the structural adjustment, the accomplishment of high value-added in existing industries and the promotion for high-tech industries as well as service industries should be the future direction of the future leading industries. In order to create atmosphere for the growth, it is crucial to achieve a social consensus about the nature of the prospective leading industries and is necessary to continue a concrete research on the related industries.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.839-841
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• 2004

This paper presents a SPMSM servo motor drive system using high performance TMS320 F281T DSP for the industrial application. This high performance DSP contains some special peripheral circuits such as PWM (Pulse Width Modulation) waveform generation circuit, Quadrature Encoder Pulse (QEP) generation circuit and Analog to Digital Converter (ADC) circuit. In this paper, a servo drive control system is constructed using high performance DPS for the overall system cost reduction and the size minimization.

• Korean Journal of Pharmacognosy
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• v.37 no.4 s.147
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• pp.235-240
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• 2006

We investigated the antioxidant activities such as DPPH radical scavenging capacity, xanthine oxidase inhibitory activity, and superoxide radical scavenging capacity of the aqueous EtOH extract and its solvent fractions of Artemisia scoparia. The ethyl acetate fraction showed high antioxidant activity, compared to positive controls such as ascorbic acid, butylated hydroxy anisole (BHA), trolox, and allopurinol in these assay systems. Moreover, we examined the inhibitory effect of solvent fractions of A. scoparia on the production of pro-inflammatory factors that the nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and prostaglandin E2 $(PGE_2)$ production activated with LPS $(1{\mu}g/ml)$ in murine macrophage cell line RAW264.7. The amounts of protein levels were determined by immunoblottting. Tn the sequential fractions of hexane and dichloromethane inhibited the NO and $PGE_2$ production and the protein level of iNOS and COX-2. These results suggest that A. scoparia may have anti-inflammatory activity through the antioxidant activity and inhibition of pro-inflammatory factors.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.10
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• pp.623-629
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• 2014

For the semiconductor device safety from over current in the digital electronic circuit system must be surely designed that it's surface mount type micro fuse device. In this paper, We has analysed to the fusing character of micro fuse as a function changed thickness of thermosetting ink epoxy. To the change of thermosetting ink epoxy thickness with in production lot, in the electrically character (fusing test in the 2 multiple over current and 10 multiple over current, surface temperature test in the 1.25 multiple over current) of micro fuse has been tested. According to the electrically character result, changed thickness of thermosetting ink epoxy in designed micro fuse withheld direct effect in both end resistance changes. Also, because high thermal energy in the micro fuse test of over current was occurred to effect such as thermal runaway and explosion. Therefore, screen printing process in the design of micro fuse using thermosetting ink epoxy is very important for production quality improvement.