• 보건행정학회지
• /
• 제9권3호
• /
• pp.33-52
• /
• 1999

The purpose of this study is to project the supply and demand for nurses till the year 2012 and to make recommendations for establishment of proper policies regarding them. To predict the supply of nurses. a baseline projection and demographic methods were employed. The derivative demand was used to forecast the demand of nurses. The results of this study provide us with valuable information on nursing manpower planning for the 21th century. Specifically. results indicate that there will be an oversupply of nurses in the near future based on the current productivity. Based on the medical law. there will be an undersupply of nurses till 2002 but an oversupply after that. Thus. the active supply of nurses must be decreased. One way to achieve this would be decreasing the size of training and education. Thus. we recommend that the number of entrances to 4 year programs will be reduced 20% in 2004. and a reduction of 20% by 2005 in 3 year programs. The results of this study suggest the following: First. a manpower bank for nurses who are trying to reenter the market must be established. Second, improvement of education and retraining is needed for the quality control of nurses. Further studies should take into consideration the above factors.

• 현장농수산연구지
• /
• 제13권1호
• /
• pp.83-102
• /
• 2011

The purpose of this study carried out to analyze production status, pricing trend and distribution status of landscape plants, so that it could predict the demand of landscape plants for the balance of supply and demand. The production amount of landscape plants made constantly increased. The annual output of shrubs increased more higher than that of trees. The prices of trees have raised consistently, but shrubs were susceptible to price fluctuations. And there were still many problems in the distribution structure. The landscaping work has focused on the metropolitan area. And large-scale nationwide projects were scheduled for coming years, so the demand of landscape plants was expected to expend. However, the lack of increase in production amounts of landscape plants, it is cause to supply problems. So, demand forecast was necessary to control the production of landscape plants.

• 품질경영학회지
• /
• 제36권4호
• /
• pp.93-101
• /
• 2008

The rare metals, used for semiconductors, PDP-LCS and other specialized metal areas necessarily, has been playing a key role for the Korean economic development. Rare metals are influenced by exogenous variables, such as production quantity, price and supplied areas. Nowadays the supply base of rare metals is threatened by the sudden increase in price. For the stable supply of rare metals, a rational demand outlook is needed. In this study, focusing on the domestic demand for chromium, the uncertainty and probability materializing from demand and price is analyzed, further, a demand forecast model, which takes into account various exogenous variables, is suggested, differing from the previously static model. Also, through the OOS(out-of-sampling) method, comparing to the preexistence ARIMA model, ARMAX model, multiple regression analysis model and ECM(Error Correction Mode) model, we will verify the superiority of suggested model in this study.

• 한국시스템다이내믹스연구
• /
• 제10권1호
• /
• pp.61-76
• /
• 2009

We try to use system dynamics to forecast the demand/supply and price, also transportation fare for iron ore. Iron ore is very important mineral resource for industrial production. The structure for this system dynamics shows non-linear pattern and we anticipated the system dynamic method will catch this non-linear reality better than the regression analysis. Our model is calibrated and tested for the past 6 year monthly data (2003-2008) and used for next 6 year monthly data(2008-2013) forecasting. The test results show that our system dynamics approach fits the real data with higher accuracy than the regression one. And we have run the simulations for scenarios made by possible future changes in demand or supply and fare related variables. This simulations imply some meaningful price and fare change patterns.

• 전자통신동향분석
• /
• 제34권3호
• /
• pp.106-113
• /
• 2019

Mobile traffic is one of the most important indexes of the growth of the mobile communications market, and it has a close relationship with subscribers' service usage patterns, frequency demand and supply, network management, and information communication policy. The purpose of this paper is to understand mobile data usage in Korea and to suggest the optimal steps for establishing the frequency supply and demand system by researching the traffic trends that reflect the characteristics of radio resources in the mobile communications field. To achieve this goal, attempts were made to increase the possibility of policy use by analyzing and forecasting mobile traffic trends, and to improve the accuracy of the research through the verification of the existing prediction results. The paper ends with a discussion of the necessity of a frequency management system based on data science.

• 대한산업공학회지
• /
• 제39권4호
• /
• pp.247-252
• /
• 2013

Korea gas corporation (KOGAS) is responsible for the whole sale of natural gas in the domestic market. It is important to forecast the daily demand of city gas for supply and demand control, and delivery management. Since there is the autoregressive characteristic in the daily gas demand, we introduce a modified autoregressive model as the first step. The daily gas demand also has a close connection with the outdoor temperature. Accordingly, our second proposed model is a temperature-based model. Those two models, however, do not meet the requirement for forecasting performances. To produce acceptable forecasting performances, we develop a weighted average model which compounds the autoregressive model and the temperature model. To examine our proposed methods, the forecasting results are provided. We confirm that our method can forecast the daily city gas demand accurately with reasonable performances.

• 한국산업경영시스템학회:학술대회논문집
• /
• 한국산업경영시스템학회 2002년도 춘계학술대회
• /
• pp.343-348
• /
• 2002

We are concerned with a long-term replenishment contract for the ARIMA demand process in a supply chain. The chain is composed of one supplier, one buyer and consumers for a product. The replenishment contract is based upon the well-known (s, Q) policy but allows us to contract future replenishments at a time with a price discount. Due to the larger forecast error of future demand, the buyer should keep a higher level of safety stock to provide the same level of service as the usual (s, Q) policy. However, the buyer can reduce his purchase cost by ordering a larger quantity at a discounted price. Hence, there exists a trade-off between the price discount and the inventory holding cost. For the ARIMA demand process, we present a model for the contract and an algorithm to find the number of the future replenishments. Numerical experiments show that the proposed algorithm is efficient and accurate.

• 디지털산업정보학회논문지
• /
• 제7권2호
• /
• pp.147-159
• /
• 2011

In this paper the demand and supply of labor are forecasted over the next 10 years for customized nurturing human resource focused on Manufacturing Industry in Chung-Nam Province. Despite that the industrial structure is rapidly changing, industrial labors are nurturing on the basis of past industrial structure. This research is conducted for reducing mismatched labors throughout forecasting human resources until 2020. As a practical approach, the BLS Methodology is partially utilized. And the previous researches and official statistics data are reviewed. In conclusion, this study presents that more human resources on Manufacturing Industry than other Industries will be needed in Chung-Nam province. In details, it shows that there will be required more Industrial labors for strategic industries for examples, Audio and Video related industry, and Car related industry which is propelling by overall local government. In additions, policy implications are developed by analyzing current status and forecasting the labor demand and supply in the Chung-Nam Manufacturing sector.

• 산업경영시스템학회지
• /
• 제33권3호
• /
• pp.162-168
• /
• 2010

Information is known to be a key element for the successful operation of a supply chain, which is required of the efficient ordering strategies and accurate predictions of demands. This study proposes a method to effectively utilize the meteorological forecast information in order to make decisions about ordering and prediction of demands by using the Taguchi experimental design. It is supposed that each echelon in a supply chain determines the order quantity with the prediction of precipitation in the next day based on probability forecast information. The precipitation event is predicted when the probability of the precipitation exceeds a chosen threshold. Accordingly, the choice of the threshold affect the performances of a supply chain. The Taguchi method is adopted to deduce a set of thresholds for echelons which is least sensitive to changes in environmental conditions, such as variability of demand distributions and production periods. A simulation of the beer distribution game was conducted to show that the set of thresholds found by the Taguchi method can reduce the cumulative chain cost, which consists of inventory and backlog costs.

• 한국산학기술학회논문지
• /
• 제12권3호
• /
• pp.1488-1494
• /
• 2011

본 연구에서는 선형회귀모형(linear regression model)을 이용하여 겨울철 일일 온수 수요 총량을 예측하는 알고리즘을 개발한다. 한국지역난방공사에서는 온수 공급 계약을 맺고 있는 아파트, 상가 및 사무용 빌딩 등에 난방 및 급탕 온수를 공급한다. 일반적으로 온수는 보일러 및 열병합 발전기를 가동하여 생산하며, 경제적인 온수 생산계획을 수립하기 위해서는 온수 수요를 정확히 파악하는 것이 중요하다. 따라서, 본 연구에서는 난방을 위한 온수 수요가 급증하는 겨울철 온수 수요의 특성을 분석하고, 선형회귀모형을 이용한 온수 수요 예측 알고리즘을 개발한다. 겨울철 일일 온수 수요는 외기온도의 영향을 많이 받는 것으로 알려져 있으나, 본 연구에서는 외기온도와 예측일 하루 전날 온수 공급 실적값을 동시에 고려할 때 예측 정확도를 크게 높일 수 있음을 확인하였다. 본 연구에서 개발하는 예측 알고리즘의 타당성을 검증하기 위해 한국지역난방공사 서울 강남지사의 2006 ~ 2009년도 온수 수요 공급 실적과 기상청의 기상정보를 이용하여 겨울철 일일 온수 수요 총량을 예측한 결과, 평균 오차율(mean absolute percentage error)이 3.87%을 넘지 않는 수준임을 확인하였다.