• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.12
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• pp.572-578
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• 2014

Heating energy was measured in an apartment housing unit with a district heating system, varying the kind of hot water distributors. Ondol coils passing through a living room raised the temperature of the room where the heating was turned off. Including this characteristic of Ondol heating into the modeling, we performed simulations and showed a verification by comparison with the results of measurements. As a result, a main flow control method, which changes hot water flow rate supplied to a housing unit according to the thermal load, can reduce the supplied flow rate and lower the return temperature, compared with a constant flow method. That can result in decreased heat loss in utility-pipe conduits even though the heating energy supplied is almost the same. An outdoor reset control that raises the temperature of the supplied hot water if the outdoor temperature falls has the effect of a quicker response in heating than the reduced flow rate and return temperature.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.11
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• pp.2987-3002
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• 2023

In 2015, the number of senior citizens aged 65 and over in Korea was 6,662,400, accounting for 13.1% of the total population. Along with these social phenomena, risk information related to the elderly is increasing every year. In particular, a fall accident caused by a fall can cause serious injury to an elderly person, so special attention is required. Therefore, in this paper, we implemented a system that monitors fall accidents and informs them in real time to minimize damage caused by falls. To this end, beacon-based indoor location positioning was performed and biometric information based on an integrated module was collected using various sensors. In other words, a multi-functional sensor integration module was designed based on Arduino to collect and monitor user's temperature, heart rate, and motion data in real time. Finally, through the analysis and prediction of measurement signals from the integrated module, damage from fall accidents can be reduced and rapid emergency treatment is possible. Through this, it is possible to reduce the damage caused by a fall accident, and rapid emergency treatment will be possible. In addition, it is expected to lead a new paradigm of safety systems through expansion and application to socially vulnerable groups.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.535-543
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• 2020

The KSA caused an error in deriving the statistical measurement items due to the misconfiguration of the safety variables and sub-modules that constitute the safety statistics framework for external causes of death, and pathogenesis, without considering the academic classification system of the field and area of the disaster/accident. By naming it as a mechanism, it was analyzed that the result of poor statistical validity has arrived. Therefore, in this study, by changing the safety parameters according to the WHO safety definition and setting the sub-modules appropriately, the categories of falls, drowning accidents, and accidents exposed to inanimate mechanical forces are classified as accidents at industrial sites and work in daily life. As a result, by systematically re-establishing the complex group of statistical items of the NSO by deriving the field of disasters/accidents according to the nature of the source of external causes of death and setting the relevant domains academically, statistical validity gets better and It is anticipated to play an important role in determining the direction of safe investment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.4
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• pp.724-730
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• 2006

The earth resistance is a essential basic factor of the performance of the earth. The earth enables system to be operated in a stable way not only against thunderbolts, unexpected transitional currents, the inflow of voltages and electric noises but also protect human life from electric shocks. In a domestic case, there is a technique criterion about earth technique but it falls short of reality since the content is very limitted, which causes a lot of problems to establish communications facilities. This paper gives the results through actual measurement or the earth resistance as reffered date in a way to improve these problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3161-3167
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• 2010

Hall sensors of BLDC(brushless DC) motor are used to detect a position information for a control mechanism, which implements an algorithm for velocity and position control. Actual azimuth and altitude were measured to evaluate a control precision. The measurement revealed comparatively good accuracy that the measured values were $2.02^{\circ}$ and $1.01^{\circ}$ respectively, and the maximum error falls within $1.86^{\circ}$. The developed monitoring system of photovoltaic generation plants is a LCU(Local Control Unit) based on an integrated monitoring system which supports 1:N method for multiple simultaneous connections, remote control and real-time system state monitoring.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.2
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• pp.153-159
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• 2016

Rivers refer to either natural or artificial structures whose primary functions are flood control and water conservation. Due to recent localized torrential downpours led by climate change, large amounts of eroded soil have been carried away, forming deposits downstream, which in turn degrades the capacity to fulfill these functions. To manage rivers more effectively, we need data on riverbed erosion and deposition. However, environmental factors make it challenging to take measurements in rivers, and data errors tend to prevent researchers from grasping the current state of erosions and deposits. In this context, the aim of the present study is to provide basic data required for river management. To this end, the author made annual measurements with a Real-time Kinematic-Global Positioning System (RTK-GPS) and a total station in Pats Cabin Canyon, Oregon, United States, and also prepared thematic maps of erosion and deposition thickness as well as water depth profiles based on a GIS spatial analysis. Furthermore, the author statistically analyzed the accuracy of three dimensional (3D) measurement points and only used the data that falls within two standard deviations (i.e. ±2σ). In addition, the author determined a threshold for a DEM of Difference (DoD) by installing measurement points in the rivers and taking measurements, and then estimated erosion and deposition thickness within a confidence interval of ±0.1m. Based on the results, the author established reliable data on river depth profiles and thematic maps of erosion and deposition thickness using pre-determined work flows. It is anticipated that the riverbed data can be utilized for effective river management.

• Journal of Engineering Education Research
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• v.11 no.4
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• pp.94-108
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• 2008

The purpose of this study falls into the development of national skill system in environmental field. The jobs were classified by the commonly used terms in the field. Consequently there are three large groups, twelve middle groups which again narrow down to smaller jobs according to the relevant characteristics of each job in the group, and forty one jobs in total in the area. Six levels were identified for the definition of job level and the development of performance level by reflecting job levels by expertise. Under the consideration of the unique characteristics of the environment field, job levels were also defined in accordance with each area such as 'environment plan and assessment', 'measurement and analysis of environment', 'environment management', 'environment design and construction', 'environment health management', 'environment resources management', 'environment management and consulting', and 'environment education'. Based on these classification, the definitions of jobs and the standards of performances by jobs and levels were resulted in through a consultation consisting of experts in the environment industry and academy.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.2
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• pp.654-670
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• 2020

Workers at construction sites are easily exposed to many dangers and accidents involving falls, tripping, and missteps on stairs. However, researches on construction site monitoring system to prevent work-related injuries are still insufficient. The purpose of this study was to develop a wearable textile pressure insole sensor and examine its effectiveness in managing the real-time safety of construction workers. The sensor was designed based on the principles of parallel capacitance measurement using conductive textile and the monitoring system was developed by C# language. Three separate experiments were carried out for performance evaluation of the proposed sensor: (1) varying the distance between two capacitance plates to examine changes in capacitance charges, (2) repeatedly applying 1 N of pressure for 5,000 times to evaluate consistency, and (3) gradually increasing force by 1 N (from 1 N to 46 N) to test the linearity of the sensor value. Five subjects participated in our pilot test, which examined whether ascending and descending the stairs can be distinguished by our sensor and by weka assessment tool using k-NN algorithm. The 10-fold cross-validation method was used for analysis and the results of accuracy in identifying stair ascending and descending were 87.2% and 90.9%, respectively. By applying our sensor, the type of activity, weight-shifting patterns for balance control, and plantar pressure distribution for postural changes of the construction workers can be detected. The results of this study can be the basis for future sensor-based monitoring device development studies and fall prediction researches for construction workers.

• Journal of Korean Physical Therapy Science
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• v.26 no.3
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• pp.70-75
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• 2019

Purpose: The purpose of this study was to investigate the changes of static and dynamic balance control ability according to the stability of shoes in elderly woman and female university student. Design: Cross-sectional study. Methods: Six elderly women and seven female university students were recruited for this study. The subject's static and dynamic balance were evaluated while wearing two different types of shoes (comfortable running shoe and masai walking shoe). The BT4 system was used to measure the static (postural sway area and velocity) and dynamic balance (limit of stability on forward, backward and left and right side). The measurement of static and dynamic balance control ability was performed in standing posture wearing comfortable running shoes and masai walking shoes. Results: In the static balance control ability, both female university students and elderly women showed significant increase in postural sway area and velocity when wearing unstable shoes (p<0.05) In addition, in the dynamic balance control ability, both female university students and elderly women showed significant decrease in limit of stability on forward and backward when wearing unstable shoes (p<0.05). Conclusion: In selecting shoes for the elderly, the stability of shoe should be considered for prevention of falls.

• Journal of the Korean housing association
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• v.20 no.5
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• pp.103-112
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• 2009

This New-Town Project has been proposed to improve the environments of deprived residential areas. This paper investigates the distribution levels of the participating parties' monetary surpluses from New-Town Projects through a case study and tentatively suggests political issues and measures. The methodology followed includes a thorough survey of the precedent theories, including a literature review concerning issues and tasks that have been raised since the development was initiated. A general assessment of the complete project is also provided with a broad perspective of the background settings. Secondly, the case study of Gil-Eum will be the focus for identifying the mechanism for the project's profit distribution levels, then for constructing a set of measuring procedures according to the stages of the project and the participating parties. This set of procedures that has been drawn out from recognizing the system, is applied to the target project and measures the amount of profit gained from each stage of the development. This also aids in collating information about the procedural arguments concerning the financial gains of the operations that have been provided. This project falls under the 'Urban and Residential Environment Improvement Act', and based on the results of each stage, the measurement of the profits of the participating parties is analyzed.