• Journal of the Korean Society for Precision Engineering
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• v.25 no.8
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• pp.29-36
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• 2008

An optical rotary encoder is easy to implement for automation system applications. In particular, the output of the encoder has a digital form pulse, which is also easy to be connected to a popular digital controller. By using an incremental encoder and a counting device, it is easy to measure angular displacement, as the number of the output pulses is proportional to the rotational displacement. This method can only detect the angular placement once a pulse signal comes out of the encoder. The angular displacement detection period is strongly subject to the change of the angular displacement in case of ultimate low velocity range. They have ultimate long detection period or cannot even detect angular displacement at near zero velocity. This paper proposes an algorithm for detecting angular displacement by using a dual encoder system with two encoders of normal resolution. The angular displacement detecting algorithm is able to keep detection period moderately at near zero velocity and even detect constant angular displacement within nominal period. It is useful for motion control applications in case of changing rotational direction at which there occurs zero velocity. In this paper, various experimental results are shown for the angular displacement detection algorithm.

• The KIPS Transactions:PartC
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• v.8C no.2
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• pp.221-233
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• 2001

오늘날 이동 에이전트 기술은 네트워크 트래픽을 효과적으로 줄이고, 서버의 인터페이스를 바꾸지 않고 클라이언트의 다양한 요청을 융통성 있게 서비스할 수 있는 기술로 여겨지고 있다. 그러나 대부분의 이동 에이전트 시스템들은 그들 자신의 구조를 적용하고 다른 방법으로 구현되어, 특정 이동 에이전트 시스템에서 생성된 이동 에이전트는 다른 에이전트 시스템에서는 사용될 수 없다. 이러한 문제를 해결하기 위하여 OMG(Object Management Group)는 이질적인 에이전트 시스템간의 상호운용선(interoperability)을 증진시킬 목적으로 이동 에이전트와 에이전트 시스템간의 공통된 개념적인 모델에 대하여 기술한 MAF(Mobile Agent Facilities) 명세를 제안하였다. 본 논문에서는 OMG MAF 명세를 만족하는 자바 기반의 SMART 시스템에 관하여 기술한다. SMART 시스템은 MAF 명세에 따른 이동 에이전트간의 상호운용성을 지원하고, MAF 명세에서 권장하는 보안 모델을 기반으로 한 독자적인 보안 기능을 제공한다. 또한 보다 안정된 에이전트 시스템의 운영을 위하여 자체적인 에이전트 및 에이전트 시스템의 영속성(persistence)과 예외처리를 지원한다.

• Journal of Sericultural and Entomological Science
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• v.26 no.1
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• pp.30-34
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• 1984

In order to investigate an endocrinological effect on metamorposis of the midgut in silkworm, Bombyx mori, 20-hydroxyecdysone and rude extract of brain (PTTH) were injected into pupal isolated abdomens, devoid of prothoracic glands and also in the brainless diapausing pupae with the prothoracic glands (so-called dauer pupae). When ecdysone was assayed abdomens, drastic morphological changes occurred in the midgut. The wet weights of midguts were found decrease as like the normal pupae at metamorphosis. Proteineous changes in epithelial midgut were also observed; pupal specific proteins (PSP) vanished while the adult proteins were newly synthesized. Similar results were also found in the changes of protein in the midgut of dauer pupae by injecting ecdysone and PTTH.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.1 s.24
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• pp.5-12
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• 2006

This study describes an SDINS/GPS/ZUPT integration algorithm for land navigation systems. The SDINS error can be decoupled in two parts. The first part is the the Schuler component which does not depend on object motion parameters, and the other is the Non-Schuler part which depends on the product of object acceleration and azimuth error. Azimuth error causes SDINS error in proportion to the traversed distance. The proposed system consists of a GPS/SDINS integration system and an SDINS/ZUPT integration system, which are both realized by an indirect feedforward Kalman filter. The main difference between the two is whether the estimate includes the Non-Schuler error or not, which is decided by the measurement type. Consequently, subtracting GPS/SDINS outputs from SDINS/ZUPT outputs provide the Non-Schuler error information which can be applied to improving azimuth accuracy. Simulation results using the raw data obtained from a van test attest that the proposed SDINS/GPS/ZUPT system is capable of providing azimuth improvement.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06c
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• pp.123-126
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• 2011

최근 전투체계는 동시에 다수의 장비들 사이에 실시간으로 데이터를 전달해야 하는데, 이러한 특성을 만족하는 통신 미들웨어로서 OMG (Object Management Group)에서 정의한 데이터 분배 서비스 (DDS ; Data Distribution Service)가 적합하다. 이를 구현한 DDS 시스템에는 RTI의 NDDS, PrismTech의 OpenSplice, 충남대학교의 ReTicom 등이 있다. 이 중 NDDS와 OpenSplice는 데이터의 영속성을 지원하지만 ReTicom에서는 영속성을 아직 지원하지 못한다. 이를 해결함과 동시에 실시간성을 보장하기 위해서 ReTicom은 메인 메모리 기반의 객체 관계형 데이터베이스를 사용하여 구현중이다. 이를 위해서는 DDS의 객체 모델 데이터를 정의하는 IDL과 객체 관계형 데이터베이스의 데이터 타입 및 구조 등이 동일하지 않기 때문에 IDL과 객체 관계형 데이터베이스간의 데이터 타입 및 구조를 변환하는 메타 모델 변환 방법이 제공되어야 한다. 본 논문에서는 이러한 메타 모델 변환 방법을 해결하고자 IDL을 구조파악이 쉬운 XML 스키마로 변환 후 이를 객체 관계형 데이터베이스의 데이터 타입 및 구조 형태로 변환 해주는 방법을 제안한다.

• The Korean Journal of Franchise Management
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• v.14 no.3
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• pp.37-52
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• 2023

Purpose: This study is to investigate the causal relationship between franchise headquarters' franchise cost and franchise satisfaction and management performance, and to verify the structural relationship between franchise cost and corporate permanence. Research design, data and methodology: The data were collected from 200 medium-sized franchisees in Seoul and analyzed using confirmatory factor analysis (CFA) to test the validity of the measurement model and the structural equation model (SEM) to identify the impact of franchise costs on corporate performance with the Amos 28.0 program. Result: Franchise costs were found to have a negative effect on franchise satisfaction and corporate permanence. It was confirmed that franchise satisfaction had a significant positive effect on management performance and corporate permanence. Franchise costs had a sequential mediating effect on franchise satisfaction and management performance, which had a significant impact on corporate permanence. Conclusions: This study expanded the theoretical scope by applying the expectation confirmation theory to corporate transactions. In addition, the franchise headquarters proposes ways to create a culture of franchise business with trust by presenting appropriate franchise costs to improve management performance and corporate permanence through franchise satisfaction.

• Journal of Advanced Navigation Technology
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• v.28 no.4
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• pp.379-385
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• 2024

INS(inertial navigation system) aligns itself using gravity and Earth's rotational rate from accelerometers and gyro sensors when stationary. Typically, ZUPT(zero velocity update), which is based on a linear error model Kalman filter, is used when it is stationary. However, such algorithms assume stationary conditions, leading to increased alignment errors or filter divergence during maritime mooring due to wave-induced motion. This paper designs a mooring alignment algorithm for maritime platforms using a Kalman filter, which uses large heading angle error model and an initial position correction technique. And it is validated by simulation. Furthermore, it is confirmed that applying this to a rotational INS dramatically improves performance through the principle of bias cancellation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.67-76
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• 2010

The purpose of this study was to suggest the growth characteristics, seasonal anthesis distribution and botanical composition of wildflower pasture. The experimental wildflower were 34 species (1 turfgrass species, 4 native wildflower species and 29 introduced wildflower species). The experiment were administered in the Chungnam National University experimental field from March, 2008 to December, 2009 and the result is as follows: the wildflower length were within the range of 8-60 cm and their up-and-down space arrangement quite good. They bloomed into several colors of nine but one or three of nine colors were biased during August, September, and October. Their anthesis was biased toward May and June, and their seasonal distribution and permanence maintenance were too difficult from August and moreover two years later (2009) because of the decrease of the botanical distribution of annual wildflower after winter, the color, seasonal distribution, and permanence of wildflower became a problem. The botanical composition of wildflower, turf grass, and weeds came to 24%, 62%, and 14% each one year later (2008) and two years later (2009) 16%, 69%, and 15% each. Being grounded upon this result, in case of wildflower pasture of spring seeding, it is more important to maintain the color, seasonal distribution, and permanence of wildflower two years later than in the establishment year.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.629-636
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• 1996

The developments of mariculture fisheries depend on both the natural environmental inputs such as sun, rain, wind, tide and the economic inputs such as ships, fuels, facilities, labor. for the enhancement of mariculture productivity in Deukryang Bay, a new attempt has been made to connect the environmental resources and the economic activity within one system. This study applies EMERGY analysis that evaluates environmental energies, fuels, goods and services in terms of solar emjoelus. In total EMERGY use $(69.65\times10^{20}\;sej/yr)$ the natural environment inputs is $78\%\;(54.60\times10^{20}\;sej/yr)$. This means that the mariculture in Deukryang Bay depends on mainly environmental resources. Net EMERGY yield ratio was 4.63 which indicated high value as a resource, EMERGY investment ratio was 0.28 that means to gain 3.6 times energy from the natural environment than those of economy. If the fisherie's products are made by renewable EMERGY input to Deukryang Bay, the calculated carrying capacity of fishes, crustaceans, shellfish and seaweeds were 1,140, 110, 1,553 and 9,074 ton/yr, respectively. If the quantity of renewable EMERGY input to mariculture grounds in Deukrysng Bay was calculated-based on only shellfish product, shellfish products was estimated as about 1,195 ton/yr.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.4
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• pp.301-308
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• 2010

This study was carried out in the Chungnam National University grassland experimental field from October, 2007 to December, 2009 in order to find out the growth characteristics, seasonal anthesis distribution and botanical composition of the wildflowers which were altogether composed of 70% sheep fescue and 30% introduced wildflowers. The experimental species contained 23 species in total to which sheep fescue (fundamental turfgrass) and 22 introduced wildflowers belonged. At the time of the anthesis of the wildflowers, the average plant height was 29.7 cm at first growing season and 34.1 cm at second growing season. They bloomed out into eight colors, but into simplified two colors during August, September, and October. The blooming season leant toward April and June and from August there were lots of difficulties in the wildflower blooming and the maintenance of their consistency. The botanical composition of wildflowers, sheep fescue, and weeds were 21%, 64%, and 15% in the first growing season (2008) and 19%, 65%, and 16% respectively, in the second growing season (2009). Based on this result, cultivating the introduced wildflower grassland has more difficulty because there is some difficulty in the wildflower seasonal distribution and the maintenance of its consistency. And thus, the introduction of more various wildflower such as perennials and flowers blooming after summer, and the seed-mixture combination method should be studied.