• Proceedings of the Korea Information Processing Society Conference
• /
• 2008.11a
• /
• pp.1008-1011
• /
• 2008

본 논문에서는 PDA에서 지속적인 상대 거리 측정 모니터링 시스템을 제안하고자 한다. 제안하는 시스템은 GPS나 다른 값비싼 디바이스를 제외하고 PDA의 기본 사양인 802.11, 무선 랜, 마이크, 스피커를 이용한다. 802.11 무선 랜을 이용하여 거리 변화의 감지 및 변화에 따른 거리를 측정한다. 거리 변화 감지는 RSSI값을 이용하고 TCP 패킷과 UDP패킷을 이용하여 RTT를 계산하고 거리 측정을 하고 기존에 있던 시스템을 통합한다. 이러한 시스템 개발은 PDA와 같은 모바일 디바이스에서 공유를 통한 멀티미디어 서비스 및 재난 상황 같은 곳에서 위치 정보 파악을 위해서 이용 가능할 것이라 예상 된다.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.1833-1837
• /
• 2004

The two-inertia system, which has the torsion vibration, is typically found in several industrial applications. This torsion vibration will effect the quality of the rolled material as well as the stability of the drive system. Thus the speed and torsion vibration of the system have to be properly controlled. This paper, I-PDA controller designed by Coefficient Diagram Method to control a two-inertia system is proposed. The experimental result shows that both of transient and steady state specification can be fulfilled but the transient response still has long rise time. In order to improve the speed of the system response, a phase lag structure of feedforward controller is introduced to I-PDA control system. It is shown that the performance of the I-PDA control system with suitable FFC has shorter rise and settling times, no overshoot and the torsion vibration can be suppressed.

• The Plant Pathology Journal
• /
• v.26 no.2
• /
• pp.185-188
• /
• 2010

This study was undertaken to isolate and to identify a fungal pathogen Monilinia sp. KV-27 associated with apple anthracnose. Rotted Fuji apples were used for the isolation of the fungus. The infected tissues were sterilized with 70% ethanol, washed with sterilized distilled water and were transferred to 50 ml containing potato dextrose broth (PDB) flasks. The peripheral hyphae of the fungal colony which developed from the infected tissues were isolated on to potato dextrose agar (PDA). On PDA plates the fungus grew well at $25^{\circ}C$ and occupied more than half of a 9 cm petri dish within 5 days. The fungal cultures on PDA were used for morphological observation and identification of the fungus. Conidiophores were produced on the gray to whitish sporodochial structures scattered on PDA plates. These conidiophores gave rise to chains of conidia, which were branched and easily detached in water. These structures were dark brown to black and consisted of hyphal masses. Conidia produced on PDA plates were hyline or light colored, lemon shaped or ellipsoidal ($10-13{\times}8.5-11{\mu}m$) in size.

• Korean Journal of Environmental Agriculture
• /
• v.28 no.4
• /
• pp.442-446
• /
• 2009

This study was undertaken to isolate and to identify a fungal pathogen Colletotrichum sp. KV-21 associated with apple anthracnose. Rotted Gala apples were used for the isolation of the fungus. The infected tissues were sterilized with 70% ethanol, washed with sterilized distilled water and were transferred to 50 ml containing potato broth (PDB) flasks. The peripheral hyphae of the fungal colony which developed from the infected tissues were isolated on to potato dextrose agar (PDA). On PDA plates the fungus grew well at $25^{\circ}C$ and occupied more than half of a 9 cm petri dish within 5 days. The fungal cultures on PDA were used for morphological observation and identification of the fungus. Conidiophores were produced on the gray to whitish sporodochial structures scattered on PDA plates which gave rise to conidiogenous cells. The structures of the conidia produced on PDA plates were subcylindrical to obovoid, fusoid, tapered and 4 to $6\;{\mu}m$ in size.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2004.03b
• /
• pp.11-19
• /
• 2004

When pile foundation constructed by driving method, it is desirable to perform monitoring and estimation of pile drivability and bearing capacity using some suitable tools. Dynamic Pile Monitoring yields information regarding the hammer, driving system, and pile and soil behaviour that can be used to confirm the assumptions of wave equation analysis. Dynamic Pile Monitoring is performed with the Pile Driving Analyser. The Pile Driving Analyser (PDA) uses wave propagation theory to compute numerous variables that fully describe the condition of the hammer-pile-soil system in real time, following each hammer impact. This approach allows immediate field verification of hammer performance, driving efficiency, and an estimate of pile capacity. The PDA has been used widely as a most effective control method of pile installations. A set of PDA test was performed at the site of Donghea-1 Gas Platform Jacket which is located east of Ulsan. The drilling core sediments of location of jacket subsoil are composed of mud and sand, silt. In this case study, the results of PDA test which was applied to measurement and estimation of large diameter open ended steel pipe pile driven by underwater hydraulic hammer, MHU-800S, at the marine sediments were summarized.

• Ocean and Polar Research
• /
• v.25 no.spc3
• /
• pp.373-384
• /
• 2003

When pile foundation is constructed by dynamic method, it is desirable to perform monitoring of drivability with pile penetration. Dynamic pile monitoring yields information regarding driving hammer, cushion, pile and soil behaviour that can be used to confirm the assumptions of wave equation analysis. In this study, dynamic monitoring of the steel pipe pile was performed with Pile Driving Analyser (PDA). The PDA utilizes the wave propagation theory to compute numerous variables which describe the conditions of the hammer-pile-soil system in real-time and following each hammer impact. This approach allows immediate field verification of hammer performance, driving efficiency, and estimation of pile bearing capacity. A series of PDA test were performed at the Ieodo Ocean Research Station (IORS) located in southeast of Marado, a southernmost small island south of Jeju Island. The drilling core sediments of Ieodo subsoil are composed of mud and sand, showing lamination and wavy or lenticular bedding, which were often bioturbated. This paper summarizes the results of PDA tests which were applied in measurement and estimation of large diameter open ended steel pipe pile driven by steam hammer, Vulcan-560 and MRBS-4600, at the marine sediments.

• Spatial Information Research
• /
• v.11 no.1
• /
• pp.41-60
• /
• 2003

It is noted that the paper mapping system for University Building Facility has many limitations in terms of data maintenance, real-time GIS data acquisition, and economic efficiency. The aim of this research was to evaluate an operational potential of an on site real-time mobile GIS technique to resolve the problem faced in the university. The idea is based upon the recent trends in the field of 'Telecommunication and Information Technology' that uses a PDA (personal Digital Assistants), wireless network computing, mobile computing, etc. A real time mobile GIS approach has been adopted, in which a PDA is linked to a wireless internet and field workers record data on the computer at the site and analyse data on site. While there should be a considerable number and variety of factors associated with real-time mobile GIS quality, this research focuses on three criteria that are identified as fundamental to customer requirements; (1) data quarry (2) spatial analysis (3) real-time GIS database building. 'Art--empirical study for a case study facility has been conducted to confirm the validity for the system. The system has been checked experimentally, enabled the field users to quarry the data required simply and execute spatial analysis (buffer, overlay etc.,) accommodating versatile alternatives on the site. Detailed visual maps can be generated over large areas quickly and easily. The PDA interface, in particular, were ideally suited for field users to interactively displaying positional information with attribute data. This system has shown to be quite convenient to maintaining a highly reliable database since it could playa crucial role in documenting at real-time basis temporal and spatial changes occurred in the facilities. It is anticipated that this research output will greatly serve to introduce the reliable and cost-effective facility mapping system in the university by overcoming serious constraints suffered from the past non-real time mobile GIS approach.

• Journal of Food Hygiene and Safety
• /
• v.14 no.4
• /
• pp.428-432
• /
• 1999

This study was performed to investigate the possible effect of sunlight on the reduction or degradation of mycelia and aflatoxins. The mycelia and aflatoxins were produced by Aspergillus parasiticus ATCC 15517 in a yeast-extract sucrose broth (YES) and potato-dextrose agar (PDA) and then exposed to sunlight. The weight of mycelia was decreased to 76.8% in 8 hours and to 66.7% in 168 hours(p<0.05). The total aflatoxin level was significantly decreased to below 50% (46.3% in the YES broth and 49.6% in the PDA) in 8 hours (p<0.05). After 168 hours, a 90.4％ degradation of aflatoxin in the YES broth and a 77.2% degradation of aflatoxin in the PDA was observed, respectively (p<0.01). The results showed that the degradation ratios of total aflatoxin level increased with increased exposure time to sunlight. These results indicate that sunlight could be an effective factor in aflatoxin degradation although its effect on mycelia was less pronounced.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 2004.11a
• /
• pp.26-26
• /
• 2004

• Proceedings of the Korea Society of Design Studies Conference
• /
• 2002.11b
• /
• pp.136-137
• /
• 2002