• Title/Summary/Keyword: absolute date

Search Result 54, Processing Time 0.03 seconds

Tree-Ring Dating of Coffin Woods Excavated from Shinnae-dong in Seoul, Korea

  • Lee, Kwang-Hee;Son, Byung-Hwa;Park, Won-Kyu
    • Journal of the Korean Wood Science and Technology
    • /
    • v.41 no.5
    • /
    • pp.406-414
    • /
    • 2013
  • This study aims to date wooden coffins excavated from graves in Shinnae-dong, Seoul, South Korea, using dendrochronology. The species of woods used to make the coffins were identified as Pinus densiflora S. et Z., one of the major conifers in Korea. Of 12 graves, 10 were successfully dated using various red-pine chronologies of South Korea. Due to the absence of the last-formed tree ring before felling, the number of sapwood rings, used to obtain likely cutting dates, had to be estimated. The terminus post quem for two coffins without plaster frames were AD 1548 and AD 1571, respectively. Eight coffins with plaster frames yielded estimated dates from AD 1664 to AD 1799. The tree-ring dates indicated that the coffins with plaster frames in Shinnae-dong were constructed approximately 100 years later than those without plaster frames.

대규모건축물적용 특수방재설비

  • 이성모
    • Fire Science and Engineering
    • /
    • v.10 no.4
    • /
    • pp.37-42
    • /
    • 1996
  • The "Intelligent Fire detecting and Extinguishing System" is an up-to-date fire protection system for modern high-rise buildings, international airports, enormous industrial facilities, dome stadiums such as specific areas in which the application of our local fire protection regulation could not be satisfied. The state-of-the art initiating devices communicated with sophisticated network control panels enable peoples to get reliable and powerful suppressions using water or gas, providing absolute protection. The Intelligent Water Cannon System, the Low Pressure $CO_2$ System and the MXL Networking Fire Alarm System introduced in this paper accomplish the dynamic protection for the special hazards.

  • PDF

Statistical Analyses of the Flowering Dates of Cherry Blossom and the Peak Dates of Maple Leaves in South Korea Using ASOS and MODIS Data

  • Kim, Geunah;Kang, Jonggu;Youn, Youjeong;Chun, Junghwa;Jang, Keunchang;Won, Myoungsoo;Lee, Yangwon
    • Korean Journal of Remote Sensing
    • /
    • v.38 no.1
    • /
    • pp.57-72
    • /
    • 2022
  • In this paper, we aimed to examine the flowering dates of cherry blossom and the peak dates of maple leaves in South Korea, by the combination of temperature observation data from ASOS (Automated Surface Observing System) and NDVI (Normalized Difference Vegetation Index) from MODIS (Moderate Resolution Imaging Spectroradiometer). The more recent years, the faster the flowering dates and the slower the peak dates. This is because of the impacts of climate change with the increase of air temperature in South Korea. By reflecting the climate change, our statistical models could reasonably predict the plant phenology with the CC (Correlation Coefficient) of 0.870 and the MAE (Mean Absolute Error) of 3.3 days for the flowering dates of cherry blossom, and the CC of 0.805 and the MAE of 3.8 for the peak dates of maple leaves. We could suppose a linear relationship between the plant phenology DOY (day of year) and the environmental factors like temperature and NDVI, which should be inspected in more detail. We found that the flowering date of cherry blossom was closely related to the monthly mean temperature of February and March, and the peak date of maple leaves was much associated with the accumulated temperature. Amore sophisticated future work will be required to examine the plant phenology using higher-resolution satellite images and additional meteorological variables like the diurnal temperature range sensitive to plant phenology. Using meteorological grid can help produce the spatially continuous raster maps for plant phenology.

Effects of Maternal Hypothyroidism on the Pubertal Development in Female Rat Offspring

  • Park, Jin-Soo;Lee, Sung-Ho
    • Development and Reproduction
    • /
    • v.25 no.2
    • /
    • pp.83-91
    • /
    • 2021
  • The present study was performed to investigate the effect of maternal hypothyroidism and puberty onset in female rat pups. To do this, we employed propylthiouracil (PTU) to prepare a hypothyroid rat model. Pregnant rats were treated with PTU (0.025%) in drinking water from gestational day 14 to postnatal day 21 of offspring. Comparison of general indices such as body and tissue weights and puberty indices such as vaginal opening (VO) and tissue histology between control and PTU-treated rats were conducted. There was no significant difference in the date of VO between control and PTU group. The body weights of the PTU group were significantly lower, only 36.8% of the control group (p<0.001). Although the absolute thyroid weight was not changed by PTU treatment, the relative weight increased significantly about 2.8 times (p<0.001), indicating that hypothyroidism was successfully induced. On the other hand, the absolute weights of the ovary and uterus were markedly decreased by PTU administration (p<0.001), and the relative weight was not significantly changed. The ovarian histology of PTU group revealed the advanced state of differentiation (i.e., presence of corpora lutea). Inversely, the uterine histology of PTU group showed underdeveloped structures compared those in control group. Taken together, the present study demonstrates that our maternal hypothyroidism model resulted in minimal effect on pubertal development symbolized by VO despite of huge retardation in somatic growth. More sophisticatedly designed hypothyroidism model will be helpful to achieve a better understanding of pubertal development and related disorders.

The Safety Survey Analysis and Consideration of Small Transformer (소형 변압기 안전성 실태 분석 및 고찰)

  • Kim, Sung-Sam
    • Journal of the Korean Society of Safety
    • /
    • v.29 no.2
    • /
    • pp.1-6
    • /
    • 2014
  • In this paper, safety certification products and safety condition of small transformer is analyzed in industries field and educational facilities. In transformer of 50places, absolute majority is step down transformer to measure of instrument. Most transformers were below 5kVA and 1~3kVA capacity was the mainstream. In industries field, 5 transformers were found without safety certification according to the Electrical Appliances Safety Control Act as cheap product prefer and lack of safety consciousness. Mark & number, voltage, date of manufacture of safety certification must show item of certification. However date of manufacture showed in product of 18%, 9places. As result of thermal imaging camera, running temperature of transformer was showed in below of target temperature. However as a narrow space of transformer and wall, power cable was touched on a ventilating flue in transformer. It was simple carelessness case that surface fouling and temperature ageing of transformer accelerate. Power poor connection, neglect of transformer in production equipment, fall damage by setup incongruity and ground omission were found in case of illogicality item of transformer.

A Study on the Valuation for Trade Remedies System and KORUS-FTA Chapter 10 between the KOREA and U.S. (한.미 무역구제제도 및 KORUS-FTA 제10장에 대한 평가 및 유의점에 관한 고찰)

  • Oh, Hyon-Suk
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.41
    • /
    • pp.237-266
    • /
    • 2009
  • KORUS-FTA are consist of articles 8. In order to the subjects are, application of a safeguard measures, conditions and limitations, provisional measures, compensation, global safeguard actions, definitions, antidumping and countervailing duties, committee on trade remedies. In especially, regarding application of a safeguard measures under KORUS-FTA, if as a result of the reduction or elimination of a customs duty under this agreement, an originating good of the other party is being imported into the territory of a party in such increased quantities, in absolute terms or relative to domestic production, and under such conditions that the imports of such originating good from the other party constitute a substantial cause of serious injury, or threat thereof, to a domestic industry producing a like or directly competitive good, the party may: suspend the further reduction of any rate of customs duty on the good provided for under this agreement; increase the rate of customs duty on the good to a level not to exceed the lesser of: the most-favored-nation (MFN) applied rate of duty on the good in effect at the time the action is taken; and the MFN applied rate of duty on the good in effect on the day immediately preceding the date this Agreement enters into force; or in the case of a customs duty applied to a good on a seasonal basis, increase the rate of duty to a level that, for each season, does not exceed the lesser of: the MFN applied rate of duty on the good in effect for the corresponding season immediately preceding the date of application of the safeguard measure; and the MFN applied rate of duty on the good in effect for the corresponding season immediately preceding the date this agreement enters into force.

  • PDF

Integrated Supply Chain Model of Advanced Planning and Scheduling (APS) and Efficient Purchasing for Make-To-Order Production (주문생산을 위한 APS 와 효율적 구매의 통합모델)

  • Jeong Chan Seok;Lee Young Hae
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 2002.05a
    • /
    • pp.449-455
    • /
    • 2002
  • This paper considers that advanced planning and scheduling (APS) in manufacturing and the efficient purchasing where each customer order has its due date and multi-suppliers exit We present a Make-To­Order Supply Chan (MTOSC) model of efficient purchasing process from multi-suppliers and APS with outsourcing in a supply chain, which requires the absolute due date and minimized total cost. Our research has included two states. One is for efficient purchasing from suppliers: (a) selection of suppliers for required parts; (b) optimum part lead­time of selected suppliers. Supplier selection process has received considerable attention in the business­management literature. Determining suitable suppliers in the supply chain has become a key strategic consideration. However, the nature of these decisions usually is complex and unstructured. These influence factors can be divided into quantitative and qualitative factors. In the first level, linguistic values are used to assess the ratings for the qualitative factors such as profitability, relationship closeness and quality. In the second level a MTOSC model determines the solutions (supplier selection and order quantity) by considering quantitative factors such as part unit price, supplier's lead-time, and storage cost, etc. The other is for APS: (a) selection of the best machine for each operation; (b) deciding sequence of operations; (c) picking out the operations to be outsourcing; and (d) minimizing makespan under the due date of each customer's order. To solve the model, a genetic algorithm (GA)-based heuristic approach is developed. From the numerical experiments, GA­based approach could efficiently solve the proposed model, and show the best process plan and schedule for all customers' orders.

  • PDF

Shipboard Secret Electronic Voting System for Information and Communication Technology-isolated Ocean Crews

  • Huh, Jun-Ho;Koh, Taehoon;Seo, Kyungryong
    • Journal of Multimedia Information System
    • /
    • v.3 no.3
    • /
    • pp.77-84
    • /
    • 2016
  • The sailors on seagoing ships experience much difficulty in communicating with their families, friends or associates ashore due to communication cost or technical difficulties so that they are sometimes unable to adapt to the rapid social changes promptly. This is mainly the result of an insufficient Information and Communication Technology (ICT)-environment on their ships. To surmount such a problem, an electronic shipboard voting system that guarantees the publicness and absolute secrecy in voting process has been proposed in this paper. The system not only helps crews to catch up with up-to-date news and provides them a feeling that they are being connected to the everyday lives of the outside world, but also allows them to cast their votes based on the newly acquired information (e.g., current political or economic situations in their respective regions and etc.).

Heuristic Aspects of the Branch and Bound Procedure for a Job Scheduling Problem (작업 스케쥴링 문제 해결을 위한 Branch & Bound 해법의 비교분석)

  • Koh, Seok-Joo;Lee, Chae-Y.
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.18 no.2
    • /
    • pp.141-147
    • /
    • 1992
  • This article evaluates the efficiency of three branch-and-bound heuristics for a job scheduling problem that minimizes the sum of absolute deviations of completion times from a common due date. To improve the performance of the branch-and-bound procedure, Algorithm SA is presented for the initial feasible schedule and three heuristics : breadth-first, depth-first and best-first search are investigated depending on the candidate selection procedure. For the three heuristics the CPU time, memory space, and the number of nodes generated are computed and tested with nine small examples (6 ${\leq}$ n ${\leq}$ 4). Medium sized random problems (10 ${\leq}$ n ${\leq}$ 30) are also generated and examined. The computational results are compared and discussed for the three heuristics.

  • PDF

A Model of Four Seasons Mixed Heat Demand Prediction Neural Network for Improving Forecast Rate (예측율 제고를 위한 사계절 혼합형 열수요 예측 신경망 모델)

  • Choi, Seungho;Lee, Jaebok;Kim, Wonho;Hong, Junhee
    • Journal of Energy Engineering
    • /
    • v.28 no.4
    • /
    • pp.82-93
    • /
    • 2019
  • In this study, a new model is proposed to improve the problem of the decline of predict rate of heat demand on a particular date, such as a public holiday for the conventional heat demand forecasting system. The proposed model was the Four Season Mixed Heat Demand Prediction Neural Network Model, which showed an increase in the forecast rate of heat demand, especially for each type of forecast date (weekday/weekend/holiday). The proposed model was selected through the following process. A model with an even error for each type of forecast date in a particular season is selected to form the entire forecast model. To avoid shortening learning time and excessive learning, after each of the four different models that were structurally simplified were learning and a model that showed optimal prediction error was selected through various combinations. The output of the model is the hourly 24-hour heat demand at the forecast date and the total is the daily total heat demand. These forecasts enable efficient heat supply planning and allow the selection and utilization of output values according to their purpose. For daily heat demand forecasts for the proposed model, the overall MAPE improved from 5.3~6.1% for individual models to 5.2% and the forecast for holiday heat demand greatly improved from 4.9~7.9% to 2.9%. The data in this study utilized 34 months of heat demand data from a specific apartment complex provided by the Korea District Heating Corp. (January 2015 to October 2017).