• Title/Summary/Keyword: periodic system

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An Expanded Real-Time Scheduler Model for Supporting Aperiodic Task Servers (비주기적 태스크 서버들을 지원하기 위한 확장된 실시간 스케줄러 모델)

  • Shim, Jae-Hong;Kim, Yeong-Il;Choi, Hyung-Hee;Jung, Gi-Hyun;Yoo, Hae-Young
    • The KIPS Transactions:PartA
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    • v.8A no.1
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    • pp.16-26
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    • 2001
  • This paper proposes an extended scheduler model that is an extension of the existing model proposed already in [4, 5], which consists of upper layer task scheduler and lower layer scheduling framework. However, in order to support aperiodic task scheduling, the task scheduler has been divided into two parts, such as periodic task control component and aperiodic task control component. Thus, the proposed model can support various bandwidth-preserving servers that can service aperiodic tasks. The model distinctly separates a classic monolithic kernel scheduler into several kernel components according to their functionality. This enables system developers to implement a new scheduling algorithm or aperiodic task server independent of complex low kernel mechanism, and reconfigure the system at need. In Real-Time Linux [6], we implemented the proposed scheduling framework representative scheduling algorithms, and server bandwidth-preserving servers on purpose to test. Throughout these implementations, we confirmed that a new algorithm or server could be developed independently without updates of complex low kernel modules. In order to verify efficiency of the proposed model, we measured the performance of several aperiodic task servers. The results showed this the performance of model, which even consisted of two hierarchical components and several modules, didnt have such high run-time overhead, and could efficiently support reconfiguration and scheduler development.

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Simulation of Temporal Variation of Acoustic Transmission Loss by Internal Tide in the Southern Sea of Jeju Island in Summer (여름철 제주 남부해역에서 내부 조석에 의한 음파 전달손실의 시간적 변화 모의실험)

  • Kim, Juho;Kim, Hansoo;Paeng, Dong-Guk;Pang, Ig-Chan
    • The Journal of the Acoustical Society of Korea
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    • v.34 no.1
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    • pp.12-19
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    • 2015
  • In this paper, temporal variations of acoustic transmission loss (TL) affected by internal tide are studied by computer simulation using oceanic data measured in the southern sea of Jeju Island in summer. Temperature was measured with depth (bottom depth are nearly 80 m) in two sites near Seogwipo coast every one hour for 25 hours during July 27 and 28, 2009. The periodic fluctuation of temperature due to the internal tide was observed and its vertical displacement was more than 10 m. In order to investigate temporal variation of TL by internal tide, acoustic propagation between two measurement sites (3.8 km distance) was simulated with a source depth of 10 m. TL variation for 1/3 octave band of 100 Hz center frequency highly coincided with tidal period but more complex variation with indistinct tidal period was observed for 1 kHz. Maximun standard deviation of TL variation was 4.2 dB for 100 Hz at 2.8 km distance from a source and it was 3.7 dB for 1 kHz. The tidal variation was also shown in detection range and its maximum variance was less than 1 km. These results imply that temporal variation of TL should be considered for acoustic researches at the southern sea of Jeju Island.

Evaluation of the Large Scale Petroleum-Contaminated Site for the Remediation of Landfarming (대규모 유류오염부지에 적용된 토양경작법의 정화효율 평가)

  • Ju, Weon-Ha;Choi, Sang-Il;Kim, Jong-Min;Kim, Bo-Kyung;Kim, Sung-Gyoo;Park, Sang-Hean
    • Journal of Soil and Groundwater Environment
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    • v.14 no.4
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    • pp.15-22
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    • 2009
  • The remediation efficiency for a large scale petroleum-contaminated site was evaluated by using the Engineered Land-farming system which was consists of the following parameters; moisture & nutrient injector data, blower system, HDPE sheet and sump system. To enhance the degradation ability in the early stage, main nutrients such as nitrogen (N) and phosphorus (P) were adjusted for the site condition. As a result of the periodic tilling process, the concentration of contaminated soil was decreased to 348 mg/kg, which was lower than 500 mg/kg (regal standards) while satisfying remediation Efficiency of 82% (the maximum concentration of 1,893 mg/kg). The appropriate temperature range for an active operation was investigated between $28.9{\sim}35.6^{\circ}C$. For the contaminated soils having different initial concentration, the TPH (Total Petroleum Hydrocarbons) concentration was decreased evenly along with the CFU (Colony Forming Unit), moisture content and contaminant concentration after 38days of gratifying the legal standards of under 500 mg/kg.

Low-Flow Frequency Analysis and Drought Outlook in Water Districts Under Climate Change Scenarios : A Case Study of Gimcheon-si, Korea (기후변화 시나리오에 따른 용수구역 기반 소구역의 가뭄전망 및 갈수빈도해석 : 김천시 지역을 중심으로)

  • Kim, Jieun;Lee, Baesung;Yoo, Jiyoung;Kwon, Hyun-Han;Kim, Tae-Woong
    • Journal of Wetlands Research
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    • v.23 no.1
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    • pp.14-26
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    • 2021
  • Increase of climate variability due to climate change has paved the way for regional drought monitoring and outlook. In particular, Gimcheon-si, Gyeongsangbuk-do, is suffering from frequent and periodic drought damage as the frequency and magnitude of drought are increasing due to climate change. For this reason, it is necessary to analyze drought characteristics for sub-districts based on water district and calculate the basic low-flow considering climate change. In this study, meteorological and hydrological drought outlook were carried out for 8 sub-districts considering the water supply system and regional characteristics of Gimcheon-si according to various climate change scenarios. In addition, the low-flow frequency analysis for the near future was also performed using the total amount of runoff and the low-flow. The overall results indicated that, meteorological droughts were found to be dangerous in the S0(1974~2019) period and hydrological droughts would be dangerous in the S2(2041~2070) period for RCP 4.5 and in S3(2071~2099) period for RCP 8.5. The results of low-flow frequency analysis indicated that future runoff would increase but drought magnitude and frequency would increase further. The results and methodology may be useful for preparing local governments' drought measures and design standards for local water resources facilities.

Construction Method of ECVAM using Land Cover Map and KOMPSAT-3A Image (토지피복지도와 KOMPSAT-3A위성영상을 활용한 환경성평가지도의 구축)

  • Kwon, Hee Sung;Song, Ah Ram;Jung, Se Jung;Lee, Won Hee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.40 no.5
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    • pp.367-380
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    • 2022
  • In this study, the periodic and simplified update and production way of the ECVAM (Environmental Conservation Value Assessment Map) was presented through the classification of environmental values using KOMPSAT-3A satellite imagery and land cover map. ECVAM is a map that evaluates the environmental value of the country in five stages based on 62 legal evaluation items and 8 environmental and ecological evaluation items, and is provided on two scales: 1:25000 and 1:5000. However, the 1:5000 scale environmental assessment map is being produced and serviced with a slow renewal cycle of one year due to various constraints such as the absence of reference materials and different production years. Therefore, in this study, one of the deep learning techniques, KOMPSAT-3A satellite image, SI (Spectral Indices), and land cover map were used to conduct this study to confirm the possibility of establishing an environmental assessment map. As a result, the accuracy was calculated to be 87.25% and 85.88%, respectively. Through the results of the study, it was possible to confirm the possibility of constructing an environmental assessment map using satellite imagery, optical index, and land cover classification.

Reviewing the Candidate Types for Other Effective Area-based Conservation Measures for Post-2020 Management Related to National Protected Areas System (Post-2020 국가 보호지역 시스템 관리를 위한 기타 효과적인 지역 기반 보전 수단(OECMs) 후보지역 유형 검토)

  • Shim, Yun-Jin;Sung, Jung-Won;Lee, Kyeong-Cheol;Kweon, Hyeong-Keun;Hong, Yong-Sik;Kang, Shin-Gu;An, Jong-Bin
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.25 no.1
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    • pp.11-23
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    • 2022
  • This study aims to systematically review the candidate types for OECMs suitable for domestic conditions in areas related to the Korea Forest Service in order to achieve the goal of establishing the protected areas and OECMs system required by Post-2020 GBF, and to provide basic data for the establishment of the national protected areas system. As a result of the study, the selection criteria for OECMs were presented, and it was found that arboretums·botanical gardens, Natural Recreation Forests, and air holes may correspond to the Candidate Types for OECMs. As a result of evaluating the possible areas for OECMs based on the OECMs selection criteria, in the case of arboretums·botanical gardens, it is judged that only conservation areas can be designated as OECMs, except for areas mainly used by visitors of arboretums·botanical gardens that fall under the BGCI conservation type among national and public arboretums·botanical gardens. However, private and school arboretums·botanical gardens have personal property ownership, so it was judged to have no effective measures to control activities that may adversely affect biodiversity, which showed limitations in designation of OECMs. Natural Recreation Forests was found to meet the OECMs selection criteria. However, private forests have personal property ownership, which limits the designation of OECMs. Therefore, it is necessary to strengthen the function of in-situ conservation in order to meet the OECMs for private and school arboretums·botanical gardens, and private forests that have personal property ownership. To this end, effective measures are needed to achieve biodiversity conservation outcomes, and it is judged that legal control and corresponding support policies (incentives) are needed. In the case of air holes, for sustainable conservation, the management boundary of air holes should be clearly defined based on the preparation of laws and guidelines related to air holes. In addition, it is judged that it is desirable to designate the competent local forest office as the management authority and conduct periodic detailed surveys of air holes, establish and implement the conservation plans based on those.

A Study on the Present Condition and Improvement of Cultural Heritage Management in Seoul - Based on the Results of Regular Surveys (2016~2018) - (서울특별시 지정문화재 관리 현황 진단 및 개선방안 연구 - 정기조사(2016~2018) 결과를 중심으로 -)

  • Cho, Hong-seok;Suh, Hyun-jung;Kim, Ye-rin;Kim, Dong-cheon
    • Korean Journal of Heritage: History & Science
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    • v.52 no.2
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    • pp.80-105
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    • 2019
  • With the increasing complexity and irregularity of disaster types, the need for cultural asset preservation and management from a proactive perspective has increased as a number of cultural properties have been destroyed and damaged by various natural and humanistic factors. In consideration of these circumstances, the Cultural Heritage Administration enacted an Act in December 2005 to enforce the regular commission of surveys for the systematic preservation and management of cultural assets, and through a recent revision of this Act, the investigation cycle has been reduced from five to three years, and the object of regular inspections has been expanded to cover registered cultural properties. According to the ordinance, a periodic survey of city- or province-designated heritage is to be carried out mainly by metropolitan and provincial governments. The Seoul Metropolitan Government prepared a legal basis for commissioning regular surveys under the Seoul Special City Cultural Properties Protection Ordinance 2008 and, in recognition of the importance of preventive management due to the large number of cultural assets located in the city center and the high demand for visits, conducted regular surveys of the entire city-designated cultural assets from 2016 to 2018. Upon the first survey being completed, it was considered necessary to review the policy effectiveness of the system and to conduct a comprehensive review of the results of the regular surveys that had been carried out to enhance the management of cultural assets. Therefore, the present study examined the comprehensive management status of the cultural assets designated by the Seoul Metropolitan Government for three years (2016-2018), assessing the performance and identifying limitations. Additionally, ways to improve it were sought, and a DB establishment plan for the establishment of an integrated management system under the auspices of the Seoul Metropolitan Government was proposed. Specifically, survey forms were administered under the Guidelines for the Operation of Periodic Surveys of National Designated Cultural Assets; however, the types of survey forms were reclassified and further subdivided in consideration of the characteristics of the designated cultural assets, and manuals were developed for consistent and specific information technologies in respect of the scope and manner of the survey. Based on this analysis, it was confirmed that 401 cases (77.0%) out of 521 cases were generally well preserved; however, 102 cases (19.6%) were found to require special measures such as attention, precision diagnosis, and repair. Meanwhile, there were 18 cases (3.4%) of unsurveyed cultural assets. These were inaccessible to the investigation at this time due to reasons such as unknown location or closure to the public. Regarding the specific types of cultural assets, among a total of 171 cultural real estate properties, 63 cases (36.8%) of structural damage were caused by the failure and elimination of members, and 73 cases (42.7%) of surface area damage were the result of biological damage. Almost all plants and geological earth and scenic spots were well preserved. In the case of movable cultural assets, 25 cases (7.1%) among 350 cases were found to have changed location, and structural damage and surface area damage was found according to specific material properties, excluding ceramics. In particular, papers, textiles, and leather goods, with material properties that are vulnerable to damage, were found to have greater damage than those of other materials because they were owned and managed by individuals and temples. Thus, it has been confirmed that more proactive management is needed. Accordingly, an action plan for the comprehensive preservation and management status check shall be developed according to management status and urgency, and the project promotion plan and the focus management target should be selected and managed first. In particular, concerning movable cultural assets, there have been some cases in which new locations have gone unreported after changes in ownership (management); therefore, a new system is required to strengthen the obligation to report changes in ownership (management) or location. Based on the current status diagnosis and improvement measures, it is expected that the foundation of a proactive and efficient cultural asset management system can be realized through the establishment of an effective mid- to long-term database of the integrated management system pursued by the Seoul Metropolitan Government.

A Study on the recognition and Attitude of Home Health Nursing System (가정간호사 제도에 대한 인식 및 태도 조사연구)

  • Lee Sung Ja
    • Journal of Korean Public Health Nursing
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    • v.12 no.1
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    • pp.132-146
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    • 1998
  • This Study was attempted to provide the basic data necessary in the development and introduction of Home Health Nursing System by investigating the recognition and attitude level of Home Health Nursing System. The data were collected by means of questionaires presented to 74 patients who had been admitted in C general hospital in Chon Ju, from June 30, 1997. As the tool for this study, the questionares developed by Kim Yong. Soon, et al (1990) and Han Bok Hee(1993) were modified and supplemented for the aim of this study. The computer was used for data analysis. The items about the charateristics of the subjects and the attitude to the management plan of Home Health Nursing System were represented as the frequency and percentage. The standard deviation and calculation average were produced on the items related to definition, recognition, necessity, expected effect of the attitude of Home Health Nursing System and the items related to admission. The ANOVA test was .used according to the characteristics of variables to analyze the necessity and difference of Home Health Nursing System. The results of this study were as follows 1) The general characteristics of the subjects were as follows ; for sex, man, $58.1\%$ ; for age, 50-59 years, $29.7\%$ ; for the level of education, high school, $51.4\%$ ; $79.7\%$ of them were married; for the family forms, small family, $73.0\%$ ; and $68.9\%$ of them take the monthly income over 100 million won. 2) The characteristics related to admissions of the subjects were as follows ; for clinic, surgical department, $78.4\%$ ; addmission not more then 7days, $47.3\%$ ; for the operation-performance $71.6\%$ of them were experienced; for the admission route, via outpatients clinic, $54.1\%$ ; for waiting period to the admission day, 1-2 days, $71.6\%$. 3) The difficulties comming from the hospitalization were related mostly to the factor that they felt hospital life more inconvenient than home.(3.66) The reasons for the difficulties in the admission which was due to insufficient beds in the hospital was related to the concentration to the general hospital because of 'The Whole National Medical Insurance System'(4.05). 4) On the previous informations about the Home Health Nursing System, those who have heard of only the name were 42 $(56.8\%)$, and on the recognition of it, they thought that it is periodic treatment by the licenced nurses for the recovering pateints after early discharge(3.73). On the attitude about the necessity of Home Health Nursing System, they thought that it is necessary because of the increasing trend of a psychological disease by the change of environment and complexity of the social structure(4.24). On the expected effect of Home Health Nursing System, they answered that it is convinient for the family of the patient to take care of them(4.l8). 5) On the attitude to the management plan of the Home Health Nursing System, those who had intention to participate in the system in the case of systemic support were 42(56.8). In the visiting time, 'visit periodically' and 'visit when the patient needs' were $28(37.8\%)$ respectively. For the application of medical insurance, if possoble, they will use $(91.9\%)$; for the method of payment for the treatment, 'pay by the time required' was $23(31.1\%)$, for the subject of management, 'National public institute must operate' was $33(44.6\%)$. 6) The relationship between the general characteristics of the subjects and the necessity of Home Health Nursing System showed the notable difference in the age (F=3.508, P<0.05) and marrage state (F=5.402, P<.023).

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A Study on the Effective Controlling System of Radio-activity Ventilation (RI사용 의료기관의 효율적인 배기관리 방안)

  • Lee, Kyung-Jae;Lee, Jin-Hyung;Kim, Kyung-Hoon;Kwack, Dong-Woo;Jo, Hyun-Duck;Ko, Kil-Man;Park, Young-Jae;Lee, In-Won
    • The Korean Journal of Nuclear Medicine Technology
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    • v.12 no.1
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    • pp.91-98
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    • 2008
  • Purpose: Radio-isotopes (RI) use has been steadily developing due to industrial and technical development in the modern medical society. Particularly, popularization of domestic cyclotrons dramatically enable hospitals to produce and use diagnostic radio-isotopes. Generally, only specific facilities such as hospitals, research institutes, nuclear power plants and universities can use radio-isotopes, they are also responsible for ventilation system. The strength of radioactivity in the air is strongly regulated and controlled by korea atomic energy law in Korea Institue of Nuclear Safety (KINS), so that air radioactivity exposure can lead to environmental pollution surrounding places. In this study, we'd like to find out the investigation and the present condition of the controlled ventilation system in domestic hospitals by an emission standard from KINS, and try to reach an agreement about how to use the ventilation system. Result: Definition of filters, features and structures of pre-filters, hepa-filters, charcol filters, filter exchange procedures and precautions are explained. RI deflation concentration and filter exchange cycle have been presented as a standard prescribed in the rules of KINS. The Radiation Control Management System (RCMS) introduced by Seoul National University Bundang Hospital linking to digital pressure gauge with computer controller in another medical facilities were described in details. Conclusions: The system of medical facilities using RI has been remarkably developing in 21 century. Especially, radiation safety control system has also been grown rapidly into the subdivision, specialization, advanced technology along with international technical improvement. However, As far as current RI ventilation system is concerned, it has nothing better than doing in the past. Preferentially, to reinforce this, more sophisticated system with strict periodic filter exchange and exhaust air control guidance should be introduced by applying brilliant domestic information technology for RCMS and digital gauge method. From personal point of view as a radiation safety manager, I have provide with present problems and improvements. Futhermore, more improved guidance should be conducted.

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Gap-Filling of Sentinel-2 NDVI Using Sentinel-1 Radar Vegetation Indices and AutoML (Sentinel-1 레이더 식생지수와 AutoML을 이용한 Sentinel-2 NDVI 결측화소 복원)

  • Youjeong Youn;Jonggu Kang;Seoyeon Kim;Yemin Jeong;Soyeon Choi;Yungyo Im;Youngmin Seo;Myoungsoo Won;Junghwa Chun;Kyungmin Kim;Keunchang Jang;Joongbin Lim;Yangwon Lee
    • Korean Journal of Remote Sensing
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    • v.39 no.6_1
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    • pp.1341-1352
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    • 2023
  • The normalized difference vegetation index (NDVI) derived from satellite images is a crucial tool to monitor forests and agriculture for broad areas because the periodic acquisition of the data is ensured. However, optical sensor-based vegetation indices(VI) are not accessible in some areas covered by clouds. This paper presented a synthetic aperture radar (SAR) based approach to retrieval of the optical sensor-based NDVI using machine learning. SAR system can observe the land surface day and night in all weather conditions. Radar vegetation indices (RVI) from the Sentinel-1 vertical-vertical (VV) and vertical-horizontal (VH) polarizations, surface elevation, and air temperature are used as the input features for an automated machine learning (AutoML) model to conduct the gap-filling of the Sentinel-2 NDVI. The mean bias error (MAE) was 7.214E-05, and the correlation coefficient (CC) was 0.878, demonstrating the feasibility of the proposed method. This approach can be applied to gap-free nationwide NDVI construction using Sentinel-1 and Sentinel-2 images for environmental monitoring and resource management.