• Title/Summary/Keyword: Changes in Time Management

Search Result 1,575, Processing Time 0.039 seconds

Stochastic Traffic Congestion Evaluation of Korean Highway Traffic Information System with Structural Changes

  • Lee, Yongwoong;Jeon, Saebom;Park, Yousung
    • Asia pacific journal of information systems
    • /
    • v.26 no.3
    • /
    • pp.427-448
    • /
    • 2016
  • The stochastic phenomena of traffic network condition, such as traffic speed and density, are affected not only by exogenous traffic control but also by endogenous changes in service time during congestion. In this paper, we propose a mixed M/G/1 queuing model by introducing a condition-varying parameter of traffic congestion to reflect structural changes in the traffic network. We also develop congestion indices to evaluate network efficiency in terms of traffic flow and economic cost in traffic operating system using structure-changing queuing model, and perform scenario analysis according to various traffic network improvement policies. Empirical analysis using Korean highway traffic operating system shows that our suggested model better captures structural changes in the traffic queue. The scenario analysis also shows that occasional reversible lane operation during peak times can be more efficient and feasible than regular lane extension in Korea.

Effects of Adolescents' Attachment to Their Parents on the Longitudinal Changes in Parental Monitoring (청소년기의 부모감독 변화에 대한 부모애착의 효과)

  • Chyung, Yun-Joo
    • Journal of Families and Better Life
    • /
    • v.32 no.1
    • /
    • pp.1-12
    • /
    • 2014
  • The purpose of this study was to examine: (1) whether the level of parental monitoring changes during adolescence; (2) if it changes, what is the pattern of the change; and (3) whether the effects of adolescents' attachment to their parents on parental monitoring are dependent on time. Six waves of data from the Korea Youth Panel Study (KYPS) were used to address the research questions. The participants of the KYPS were 3,449 (1,725 boys and 1,724 girls) adolescents who participated in the study once a year for 6 years (from the 2nd grade in middle school until their high school graduation). Latent growth modeling (LGM) was used to analyze the data. The findings are as follows: the level of parental monitoring significantly increased over the six waves of the study, and the adolescents' attachment to their parents was a time-dependent predictor of parental monitoring. The results indicate that the quality of adolescents' attachment to their parents is an important factor that makes a difference in the level of parental monitoring by, possibly, affecting the level of adolescents' disclosure to their parents.

A Basic Study on the Development of Profit Risk Management Model for Apartment Projects (아파트 개발 프로젝트의 수익 리스크 관리모델에 관한 기초연구)

  • Son, Seunghyun;Lee, Sungho;Han, Bumjin;Na, Young-Ju;Kim, Ji-Myung
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2022.11a
    • /
    • pp.215-216
    • /
    • 2022
  • Profit, the performance of an apartment development project, is directly affected by the sales ratio, unit sale price, financial costs, land costs and construction costs. However, these factors fluctuate in response to changes in the environment, including various stake holders, and the profits fluctuate as a result. In order to ensure that profits are managed within target levels, these factors must be able to be predicted, controlled and monitored and managed up to the start, sale, and end stages of the project. The purpose of this study is to develop a profit risk management model for apartment development projects. The results of this study will contribute to the establishment of academic basis for the dynamic management of project profits that fluctuate with time and environment. And in practice, it will help project developers manage their business revenue to the proper level. In addition, the risks that occur from time to time can be identified quantitatively and visually, and it is expected that it will be easier to derive consensus points for smooth business progress by reducing conflicts of interest among stakeholders.

  • PDF

A Study on Efficient Building Energy Management System Based on Big Data

  • Chang, Young-Hyun;Ko, Chang-Bae
    • International journal of advanced smart convergence
    • /
    • v.8 no.1
    • /
    • pp.82-86
    • /
    • 2019
  • We aim to use public data different from the remote BEMS energy diagnostics technology and already established and then switch the conventional operation environment to a big-data-based integrated management environment to operate and build a building energy management environment of maximized efficiency. In Step 1, various network management environments of the system integrated with a big data platform and the BEMS management system are used to collect logs created in various types of data by means of the big data platform. In Step 2, the collected data are stored in the HDFS (Hadoop Distributed File System) to manage the data in real time about internal and external changes on the basis of integration analysis, for example, relations and interrelation for automatic efficient management.

Research on the positive impact of flexible work on organization and job performance (The case of introduction of M company time difference commuting system) (유연근무가 조직과 직무성과에 미치는 긍정적인 영향에 대한 연구 (M사 시차출퇴근 제도 도입 사례 중심으로))

  • Lee, Hee;Lee, Man-Soo
    • Journal of the Korea Safety Management & Science
    • /
    • v.19 no.4
    • /
    • pp.253-260
    • /
    • 2017
  • Due to dramatic changes in the trend of corporate management in economics, labor and government, companies are being asked to adapt creative and innovative organizational culture in order to keep sustainability. Under the circumstances, flexible working hour becomes one of very effective method for organization culture improvement. Recently, M company has introduced the new policy of working hours that employees can choose a couple of different time options depending on their personal situations. And it turns out to be very effective to work & life balance, increasing organizational vitality, improving efficiency of business and productivity, recruitment of core human resources, and prevention of deviation; both team and personal performance levels has significantly improved. Therefore, it is highly recommended to adapt flexible working policies for companies seeking for a long term, sustainable corporate vision.

Fault Tolerant Clock Management Scheme in Sensor Networks (센서 네트워크에서 고장 허용 시각 관리 기법)

  • Hwang So-Young;Baek Yun-Ju
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.31 no.9A
    • /
    • pp.868-877
    • /
    • 2006
  • Sensor network applications need synchronized time to the highest degree such as object tracking, consistent state updates, duplicate detection, and temporal order delivery. In addition, reliability issues and fault tolerance in sophisticated sensor networks have become a critical area of research today. In this paper, we proposed a fault tolerant clock management scheme in sensor networks considering two cases of fault model such as network faults and clock faults. The proposed scheme restricts the propagation of synchronization error when there are clock faults of nodes such as rapid fluctuation, severe changes in drift rate, and so on. In addition, it handles topology changes. Simulation results show that the proposed method has about $1.5{\sim}2.0$ times better performance than TPSN in the presence of faults.

Sequential Changes of Plasma C-Reactive Protein, Erythrocyte Sedimentation Rate and White Blood Cell Count in Spine Surgery : Comparison between Lumbar Open Discectomy and Posterior Lumbar Interbody Fusion

  • Choi, Man Kyu;Kim, Sung Bum;Kim, Kee D.;Ament, Jared D.
    • Journal of Korean Neurosurgical Society
    • /
    • v.56 no.3
    • /
    • pp.218-223
    • /
    • 2014
  • Objective : C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are often utilized to evaluate for postoperative infection. Abnormal values may be detected after surgery even in case of non-infection because of muscle injury, transfusion, which disturbed prompt perioperative management. The purpose of this study was to evaluate and compare the perioperative CRP, ESR, and white blood cell (WBC) counts after spine surgery, which was proved to be non-infection. Methods : Twenty patients of lumbar open discectomy (LOD) and 20 patients of posterior lumbar interbody fusion (PLIF) were enrolled in this study. Preoperative and postoperative prophylactic antibiotics were administered routinely for 7 days. Blood samples were obtained one day before surgery and postoperative day (POD) 1, POD3, and POD7. Using repeated measures ANOVA, changes in effect measures over time and between groups over time were assessed. All data analysis was conducted using SAS v.9.1. Results : Changes in CRP, within treatment groups over time and between treatment groups over time were both statistically significant F(3,120)=5.05, p=0.003 and F(1,39)=7.46, p=0.01, respectively. Most dramatic changes were decreases in the LOD group on POD3 and POD7. Changes in ESR, within treatment groups over time and between treatment groups over time were also found to be statistically significant, F(3,120)=6.67, p=0.0003 and F(1,39)=3.99, p=0.01, respectively. Changes in WBC values also were be statistically significant within groups over time, F(3,120)=40.52, p<0.001, however, no significant difference was found in between groups WBC levels over time, F(1,39)=0.02, p=0.89. Conclusion : We found that, dramatic decrease of CRP was detected on POD3 and POD7 in LOD group of non-infection and dramatic increase of ESR on POD3 and POD7 in PLIF group of non-infection. We also assumed that CRP would be more effective and sensitive parameter especially in LOD than PLIF for early detection of infectious complications. Awareness of the typical pattern of CRP, ESR, and WBC may help to evaluate the early postoperative course.

Prediction of Land Use/Land Cover Change in Forest Area Using a Probability Density Function

  • Park, Jinwoo;Park, Jeongmook;Lee, Jungsoo
    • Journal of Forest and Environmental Science
    • /
    • v.33 no.4
    • /
    • pp.305-314
    • /
    • 2017
  • This study aimed to predict changes in forest area using a probability density function, in order to promote effective forest management in the area north of the civilian control line (known as the Minbuk area) in Korea. Time series analysis (2010 and 2016) of forest area using land cover maps and accessibility expressed by distance covariates (distance from buildings, roads, and civilian control line) was applied to a probability density function. In order to estimate the probability density function, mean and variance were calculated using three methods: area weight (AW), area rate weight (ARW), and sample area change rate weight (SRW). Forest area increases in regions with lower accessibility (i.e., greater distance) from buildings and roads, but no relationship with accessibility from the civilian control line was found. Estimation of forest area change using different distance covariates shows that SRW using distance from buildings provides the most accurate estimation, with around 0.98-fold difference from actual forest area change, and performs well in a Chi-Square test. Furthermore, estimation of forest area until 2028 using SRW and distance from buildings most closely replicates patterns of actual forest area changes, suggesting that estimation of future change could be possible using this method. The method allows investigation of the current status of land cover in the Minbuk area, as well as predictions of future changes in forest area that could be utilized in forest management planning and policymaking in the northern area.

Performance Comparison of LSTM-Based Groundwater Level Prediction Model Using Savitzky-Golay Filter and Differential Method (Savitzky-Golay 필터와 미분을 활용한 LSTM 기반 지하수 수위 예측 모델의 성능 비교)

  • Keun-San Song;Young-Jin Song
    • Journal of the Semiconductor & Display Technology
    • /
    • v.22 no.3
    • /
    • pp.84-89
    • /
    • 2023
  • In water resource management, data prediction is performed using artificial intelligence, and companies, governments, and institutions continue to attempt to efficiently manage resources through this. LSTM is a model specialized for processing time series data, which can identify data patterns that change over time and has been attempted to predict groundwater level data. However, groundwater level data can cause sen-sor errors, missing values, or outliers, and these problems can degrade the performance of the LSTM model, and there is a need to improve data quality by processing them in the pretreatment stage. Therefore, in pre-dicting groundwater data, we will compare the LSTM model with the MSE and the model after normaliza-tion through distribution, and discuss the important process of analysis and data preprocessing according to the comparison results and changes in the results.

  • PDF

A Study on the successful model of the e-business for management renovation (경영혁신을 이한 e-비즈니스의 성공모델에 대한 연구)

  • Jo, Jae-Wan
    • Journal of Digital Convergence
    • /
    • v.4 no.2
    • /
    • pp.109-126
    • /
    • 2006
  • The United States Intel company and these enterprises which Andy Grove President talks exception are without coming out at the Internet enterprise and the hereafter 5 year back side separately it means the necessity which will write the word which is a Internet enterprise will lose. When that time about, it puts upper volume from the Internet territory which is will open the competition where the relation enterprises are keen the winner will be undertaken the existing enterprises and the place where it receives the footlights where the e-business is many in this recent times which it talks, the reason the whole world becomes connection with the Internet, the frame of the social whole changes and the arrival result completeness sincerity pursuit of information comes to be possible simultaneously, it is changing as the product army which is complicatedly diversified from the product army where the craving of the customer becomes simplification. The consequently quick doctor decision and efficient manufacturing environment construction are demanded and Product Life cycle becomes shortening, the e-Business from the digital management environment which changes suddenly the necessity is plentifully raising its head with plan of competitive power security of the enterprise and management renovation. Successful of the e-business model and failure instances there is a depth from the research which it sees and after trying to investigate, it originated to the advancement of digital environment the strategies and to sleep against the successful model of the e-business for a new management renovation presentation it tries it does.

  • PDF