• Title/Summary/Keyword: Change-point model

Search Result 742, Processing Time 0.03 seconds

Synchronization Phenomenon between Export Weight & Control Volume, Inland Cargo, Export Cargo, Ship Departure (수출중량과 관제탑관제량, 내항화물입항, 수출화물수송 그리고 선박출항과의 동조화현상)

  • Kim, Shin-Joong;Choi, Soo-Ho
    • Journal of Digital Convergence
    • /
    • v.18 no.12
    • /
    • pp.195-204
    • /
    • 2020
  • The purpose of this study is to look for the relationship between export weight and control volume, inland cargo, export cargo transport, ship departure. The analysis period were used for a total of 113 monthly data from January 2011 to May 2020. Data were retrieved from the Korean Statistical Information Service of the Statistics Korea. The data used in this study were performed numerical analysis, index analysis and model analysis using the rate of change from the same month of the previous year. In the trend of the increase rate, the amount of control has plummeted from 150% to 60% due to the influence of Corona 19 in the beginning of 2020. At the same time, export weight and export cargo transport also decreased. As a result of the analysis, export weight showed relatively high synchronization with export cargo transport and control volume. On the other hand, export weight and inland cargo showed relatively low synchronization. Export weight is expected to continue in 2020 after the fluctuation rate began to decrease after 2019. If we can find the point of rebound in control volume or export cargo transport in the future, we can predict the point of increase in export weight. We expect to see an increase in export weight as soon as possible.

Study on Permeability, Optimum Yield and Long-term Stability in Alluvial Well with Filter Layer Change (충적우물에서 필터층 변화에 따른 투수특성, 적정양수량 및 장기적 안정성에 대한 연구)

  • Song, Jae-Yong;Lee, Sang-Moo;Choi, Yong-Soo;Kim, Ki-Joon;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
    • /
    • v.28 no.1
    • /
    • pp.101-115
    • /
    • 2018
  • This study was carried out to evaluate the effects of various filter conditions on unconfined aquifer (alluvial aquifer). We made model test device which has filter layer, pumping well and observation well which consist of sand layer and gravel layer to test. Step drawdown test and long term pumping tests were carried out using the device. The permeability characteristics of each test group were confirmed and the optimal yield was calculated. As a result of comparing the optimal yield of double filter and single filter in sand, dual-filter SD-300 was valued at 216.8 % higher final optimal yield than single-filter SS-300. Comparing the dual filter SD-300 and the single filter SS-100 with a thin filter layer, dual-filter SD-300 was valued at 709.2% higher final optimal yield than single-filter SS-300. As a result of analysis of optimal yield change over time, It was confirmed that the ratio of optimal yield of single filter and dual filter increase over time. In order to evaluate the long-term change in water intake efficiency, we considered the point at which the initial optimal yield was reduced by 50%. The dual filter SD-300 is about 351.1% higher than SS-300, which is the same thickness filter, and about 579.0% higher than SS-100. From these results, Assuming that the point at which the initial quantity of water intake is reduced to 50% is the well life, double filters are expected to increase their lifespan by about 3.5 times over single filters of the same thickness and by about 5.8 times over typical single filter. These results can be used to design wells to river bank filtration or filtered seawater. In addition, it is possible to clarify the effect of the double filter through the comparison with the future field test results.

A Study on the Contact Resistance according to the Tightening and Overlapping area of Bus Bar (부스 바의 체결 및 중첩 구간에 따른 접촉 저항에 관한 연구)

  • Kim, Hyun-Woo;Son, Yung-Deug
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.7
    • /
    • pp.56-62
    • /
    • 2018
  • The bus bar is an electrical connection widely used for the power supply of skyscrapers and power distribution and industrial equipment electrical panels in industrial plants. There are various materials to be considered in the design of the bus bar, such as material based on the use environment, the sectional area according to the power capacity, the length of the surface circumference, and the tightening method. Even with a bus bar manufactured to a size of sufficient power capacity in the design, if the actual tightening is incorrect, it may lead to fire due to deterioration. For these reasons, a variety of research on the temperature rise of the electrical contact point has continued. However, the temperature rise of the contacts is a consequence of the result, not a direct cause. In this paper, the influence of contact resistance on the fastening force and the overlapping section of the bus bar are investigated by measuring the change in resistance from building the specimen. A total of eight bus bar specimens were manufactured and measured. Resistance was measured by varying the clamping force and the interval between overlapping sections when the specimens were crossed. We propose a safe power connection model by analyzing the contribution of these factors to the actual contact resistance change.

The Effects of the Intention Promotion Program on the Diet of Workers with Hyperlipemia based on the Theory of planned Behavior (식이이행 의도증진을 위한 중재가 고지혈증 근로자의 식이이행 의도 및 식이이행도에 미치는 영향)

  • Hyun, Hye-Jin;Park, Yeon-Hwan
    • Korean Journal of Occupational Health Nursing
    • /
    • v.9 no.1
    • /
    • pp.39-48
    • /
    • 2000
  • Hyperlipemia is the most leading risk factor of cardiovascular disease which is the main cause of death in Korea. However, there is a tendency to neglect the prevention and treatment since it has no specific symptoms. It has been reported that the level of serum-lipid can be lowered by the improvement of eating habits. Therefore, it is highly likely that the development of programs on the improvement of eating habits through behavioral theory is required to the community nursing practice. The theory of planned behavior, which assumes that human behaviors are determined by one's intention to carry out the behavior, can be characterized by the point that behaviors are not only individual factors but also social behaviors relating to subjective norms. It is widely recognized that this theory has a high predictability on health behavior due to it's simplicity clearness, and measurability as well as high quality of being general. Thus, the theory of planned behavior could be useful in developing a model of a health promotion program to the change of behaviors of the risk group of cardiovascular disease. Consequently, based on the theory of planned behavior, the purpose of this study is to develop an intention promotion program of the diet, and then to testify the effects. The sample of this study consisted of 26 industrial workers who had proved hyperlipemia from a medical examination in 1996 (experimental group 13, control group 13). The intention promotion program, which includes education, monitoring, pressure, counselling on the level of individuals, families and organizations, was conducted for 10 weeks The purpose of this program was to promoting intention of the diet through changes of the prerequisite factors of intention such as behavioral belief, outcome evaluation, normative belief and control belief. When it came to data analysis, the ${\chi}^2$-test and Fisher's Exact test were used to compare the general characteristics between the experimental and the control group, an independent t-test for the other variables. ANOVA was used to the test hypothesis, and the Pearson correlation test for variable's correlation. The results of this study can be summarized as follows ; 1) There was a significant increase in the intention(F=18.51, p=.00) of diet in the experimental group. 2) Diets(F=32.51, p=.001) in the experimental group were better carried out than in the control group. 5) There was a moderate correlation between the intention of diet and performance (r=.587. p=.003). From the results, it can be concluded that the intention promotion program is very effective, leading to the change of health promotion behavior. Above all, it is really valuable that the intention promotion program in this study regards health promotion behavior as a social behavior and that intervention was done on the level of family and organization. Consequently, when performing a health promotion program, social approach elevating the intention should go hand in hand in order to make the program effective.

  • PDF

The Effect of Problem Solving with Task-based Activities On Understanding of Major concepts and Learning attitude in 'Applications of Information and Communication Technology' Subject in Technology.Home Economics (기술.가정과 '정보통신기술의 활용' 단원에서 문제 해결 과제 중심 수업이 개념 이해와 학습 태도에 미치는 효과)

  • Jung, A-Long;Lee, Yong-Jin
    • 대한공업교육학회지
    • /
    • v.36 no.1
    • /
    • pp.167-190
    • /
    • 2011
  • The purpose of this study is to identify the effect of problem solving with task-based activities on understanding of major concepts and learning attitude in 'Applications of ICT' subject. In teaching the 4th class of 'Applications of ICT' subject, problem solving with reasoning task-based activities are used for the experimental groups and instructor-oriented teaching for the comparative groups. The results are as follows: First, no meaningful difference was found in the pretest result of concepts of ICT, while posttest found that the students with problem solving with reasoning task-based activities in experimental group marked average 5.87 point higher than the control group and showed meaningful difference at significance level p<.05. Dividing concepts about Information Communication Technology into four domains, there were no meaningful difference between two groups in the concept test about communication principles and methods and network, while the test results about the other two concepts, that is, expressions and patterns of information and compositions and types of communication network, showed the meaningful difference at significance level p<.05. Second, the research proved that the experimental group with problem solving with reasoning task-based activity teaching, compared to the control group with lecture, showed desirable change in learning attitude. From the results, the solving with reasoning task-based activity model is better teaching-learning method compared to lecture, revealing positive change in understanding major concepts of information and communication technology and learning attitude.

Nursing Knowledge/Power and Practice in Pediatric Intensive Care Unit (간호학적 지식/권력과 실무: 아동중환자실을 중심으로)

  • Lee Eun Joo;Hong Kyung Ja
    • Child Health Nursing Research
    • /
    • v.7 no.1
    • /
    • pp.85-95
    • /
    • 2001
  • The purpose of this study was to reveal what influences the divergent methodological researches have brought the nursing practice in during the past 3 decades. The nursing record sheets ie, the nursing discourses were analyzed to know the knowledges that were recorded, accepted and communicated in nursing practice at pediatric intensive care units, and unclosed the philosophical and methodological position of that knowledges. The texts were 13 sheets, 3 kinds of nursing record(7 24hours flow charts, 4 nursing information record sheets and 2 transfer record sheets) used at 4 hospitals. The unit of analysis was 'word'. First, all words of the sheets were listed up, clustered into categories based on their contents. And then, the larger conceptual themes were drawn to elucidate the effect of the knowledge/power and the philosophical and methodological position of that knowledges. To enhanced the validity of the analysis, the data were analyzed by two researchers. The 'words' were classified into 3 categories; 'general information', 'assessment' and 'inter-vention'. The conceptual themes of the texts were 'the gaze for quantification and objectification' and 'technical/assimilated caring'. This themes reflected the logic positivistic and biomedical view that had dominated at clinical practice. Nursing has endeavored to resist the logic-positivistic knowledge/power and to established the nursing knowledge/power based on multiple philosophies and methodologies, especially phenomenological-interpretative. But the results of this study revealed that such efforts in nursing theory and research couldn't influenced the knowledge of practice. Logic positivism was yet so strong and the biomedical model yet dominated in the clinical practice. It identified that the borrowed theory and the knowledge from the received view gave nursing the power. But they were modalities that reinforced the dominant, medical power. Nursing has investigate the other positions (feminism, Habermas' critical social theory and Foucault's discourse theory). This positions suggest different assumptions but share the common concepts; equality, emancipation and freedom. The important point is how make these concepts the practical for nursing knowledge/power in practice. We must recognize that the praxis at clinical setting take place at the field unlike theoretical praxis. The change of clinical practice is the social, economic and political change.

  • PDF

Suggestion of Modified Compression Index for secondary consolidation using by Nonlinear Elasto Viscoplastic Models (비선형 점탄소성 모델을 이용한 2차압밀이 포함된 수정압축지수개발)

  • Choi, Bu-Sung;Im, Jong-Chul;Kwon, Jung-Keun
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.10a
    • /
    • pp.1115-1123
    • /
    • 2008
  • When constructing projects such as road embankments, bridge approaches, dikes or buildings on soft, compressible soils, significant settlements may occur due to the consolidation of these soils under the superimposed loads. The compressibility of the soil skeleton of a soft clay is influenced by such factors as structure and fabric, stress path, temperature and loading rate. Although it is possible to determine appropriate relations and the corresponding material parameters in the laboratory, it is well known that sample disturbance due to stress release, temperature change and moisture content change can have a profound effect on the compressibility of a clay. The early research of Tezaghi and Casagrande has had a lasting influence on our interpretation of consolidation data. The 24 hour, incremental load, oedometer test has become, more or less, the standard procedure for determining the one-dimensional, stress-strain behavior of clays. An important notion relates to the interpretation of the data is the ore-consolidation pressure ${\sigma}_p$, which is located approximately at the break in the slope on the curve. From a practical point of view, this pressure is usually viewed as corresponding to the maximum past effective stress supported by the soil. Researchers have shown, however, that the value of ${\sigma}_p$ depends on the test procedure. furthermore, owing to sampling disturbance, the results of the laboratory consolidation test must be corrected to better capture the in-situ compressibility characteristics. The corrections apply, strictly speaking, to soils where the relation between strain and effective stress is time independent. An important assumption in Terzaghi's one-dimensional theory of consolidation is that the soil skeleton behaves elastically. On the other hand, Buisman recognized that creep deformations in settlement analysis can be important. this has led to extensions to Terzaghi's theory by various investigators, including the applicant and coworkers. The main object of this study is to suggestion the modified compression index value to predict settlements by back calculating the $C_c$ from different numerical models, which are giving best prediction settlements for multi layers including very thick soft clay.

  • PDF

(A) Study on the Structure Change of Financial Industrial for strengthening Global Financial Control (글로벌 금융 규제 강화에 따른 금융산업의 구조변화에 대한 연구)

  • Ham, Hyung-Bum;Choi, Chang-Youl
    • International Commerce and Information Review
    • /
    • v.16 no.2
    • /
    • pp.47-67
    • /
    • 2014
  • Since the global financial crisis, criticism against the integrity of financial institutions proposed new financial regulations such as Basel III. These systems are expected to have impacts multilaterally on management and structure of mid- and long-term financial industry. It is also believed that financial institutions will inevitably review business model to respond to these enhanced regulations. The ongoing global financial regulation pursues regulation scope extension, introduction of global regulatory capital system, introduction of global liquidity, etc. As for quantitative index, Basel Committee on Banking Supervision is promoting QIS which is discussed mainly on implementation time from the juridical point of view. This study aims to present domestic banking industry's structural changes depending on regulation enhancement of foreign countries after global financial crisis, and suggest strategy that improves competitiveness of products. Looking at the research result, global financial regulation requires compliance with the regulations through treaties but it shows negative time center around banks. Furthermore, it is also pointed out financially advanced countries' passive attitude on regulation enhancement is problem. Therefore, regulations differentiated between developing and developed countries, dualistic regulations on financial industry, participation of advanced nations, etc are the postulation to change the structure of financial industry.

  • PDF

The homogenization analysis for permeability coefficients by fracture aperture variations (균질화 해석법을 이용한 단열 간극변화에 따른 투수계수 해석)

  • 채병곤
    • The Journal of Engineering Geology
    • /
    • v.14 no.1
    • /
    • pp.47-60
    • /
    • 2004
  • The permeability coefficients were calculated by the homogenization analysis method with sufficient consideration of fracture geometry dependent on aperture change. According to the results of aperture measurements using a confocal laser scanning microscope, apertures on each measuring point display different magnitudes, indicating that fracture walls can not be assumed as parallel feature. After construction of fracture model based on the aperture values measured on each pressure level, the homogenization analysis was conducted to compute permeability coefficients. The calculated permeability coefficients distribute in the ranges of $10^{-1}~10^{-3}cm/sec$. Most of the specimens show decreasing permeability coefficients with the increase of the applied pressure. However, the decreasing rates of permeability coefficients do not show a constant trend on each pressure level. This phenomenon is well matched to the observation results of Chae et al. (2003). It proves that aperture change strongly influences on permeability characteristics. Three sections of each specimen have all different values of permeability coefficient. It suggests that the variation of permeability coefficient depends sensitively on aperture magnitudes and characteristics of fracture geometry. It is very important to consider accurate fracture geometries for analysis of permeability characteristics in rock fractures bearing different aperture distribution. Therefore, it needs to consider sufficiently the fracture geometries for calculating the permeability coefficients of fractures.

Analysis of Coefficiency According to Blade rpm Change in Tidal Current Power Generation System (조류발전 시스템 내 블레이드 회전수 변화에 따른 효율 특성 분석)

  • Lee, Uk Jae;Han, Seok Jong;Bak, Da In;Jeong, Shin Taek
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.31 no.5
    • /
    • pp.314-319
    • /
    • 2019
  • The numerical simulation method was used to analyze the flow velocity change and mechanical coefficient characteristics of the blade in the shroud system that changes with the initial flow velocity and the blade rpm. In the analysis condition, the initial flow velocity was varied from 0.35 m/s to 1.0 m/s, and the blade rpm varied from 50 rpm to 300 rpm. Through this, the mechanical coefficient was estimated. The flow velocity changes tended to increase more than 1.8 times at the middle point compared to the inlet. When the flow velocity ratio was 0.75 m/s compared to the initial flow velocity of 0.5 m/s, the flow velocity ratio decreased. The mechanical coefficient using the torque of the blade also showed the highest coefficient at 0.5 m/s, and the trends were similar. On the other hand, the maximum coefficient was estimated to be about 20.88% in TSR 4.77 when the initial flow velocity was 0.5 m/s. The mechanical coefficient analysis of blades in this study is expected to provide the basic data for hydraulic model experimental.