• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.40 no.5
• /
• pp.421-428
• /
• 2022

The earthwork is a core process of all constructions, and compaction measurement of earthwork play an important role in improving productivity. The analog tests such as Plate Bearing Test and Sand-cone occupy current compaction measurement techniques. Due to advanced 4th Industrial Revolution, research on analog tests combined smart construction technology are actively conducted. DCPT (Dynamic Cone penetration Test), simpler and faster than conventional tests, has recently on rise. However, it is also an analog that measures data manually and has several disadvantages such as history management and data verification. The IoT-based DCPT system developed in this study combines digital wire sensors, mobile phones, and Bluetooth with conventional DCPT. Compare to conventional test methods, IoT-based DCPT has advantages such as performance time, single-person measurement, low cost, mobile-based management, and real-time data verification. In addition, a test bed was built to verify IoT-based DCPT. The test bed was built under similar conditions to the actual earthworks site through roller equipment. DCPT data obtained from 322 stations. As a result, IoT-based DCPT showed good performance, and the test bed was also showed stable results as the compaction was carried out.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.26 no.3
• /
• pp.29-38
• /
• 2022

In this study, the shaking table tests were carried out on six types of non-structural elements installed on a full-scale two-story steel structure. The shaking table tests were performed for non-structural elements with and without seismic isolators. In this study, the seismic performance of Uninterruptible Power Supply (UPS) specimens was tested and investigated. Non-seismic details were composed of conventional channel section steel beams, and the seismic isolators were composed of high damping rubber bearing (HDRB) and wire isolator. The input acceleration time histories were artificially generated to satisfy the requirements proposed by the ICC-ES AC156 code. Based on the test results, the damage and dynamic characteristics of the UPS with the seismic isolator were investigated in terms of the natural frequency, damping ratio, acceleration time history responses, dynamic amplification factors, and relative displacements. The results from the shaking table showed that the dynamic characteristics of the UPS including the acceleration response were significantly improved when using the seismic isolator.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.35 no.1
• /
• pp.45-55
• /
• 2022

Because boundary confinement details proposed in the current design standards are significantly inferior in workability and production quality, it is necessary to develop boundary confinement details of RC structural walls that are capable of ensuring seismic performance and workability. With the recent development of the wire rod manufacturing technology, various pre-fabricated continuous hoop details can be manufactured. In this study, an analysis was conducted on the moment-curvature relationship of RC structural walls to which the pre-fabricated continuous hoop details were applied. According to the nonlinear cross-section analysis, the RC structure wall to which the details of the pre-fabricated continuous hoop details are applied can ensure seismic performance as the area of the pre-fabricated continuous hoop increases. Based on these research results, when applying the pre-fabricated continuous hoop in detail, it is necessary to secure the area of the pre-fabricated continuous hoop as much as the area of the existing boundary confinement.

• Journal of Wetlands Research
• /
• v.25 no.2
• /
• pp.91-98
• /
• 2023

Some concrete wastewater generated during construction is in the form of non-point pollution sources that workers, managers, and users are unaware of, and it is not easy to manage as it flows through sewage pipes. Due to these characteristics, construction sludge is inflow into rivers and sewage pipes in the form of non-point pollution sources in an unmanaged state. This study applied the D.W.S method to the concrete retaining wall removal method installed on the road, and the resulting concrete wastewater was physically and chemically treated through a mobile sewage treatment facility, and it was examined whether it met the removal efficiency and wastewater discharge acceptance standards. Accordingly, it is intended to meet the standards for effluent concentration of wastewater during construction by removing 73.5% of BOD and 89.1% of SS through physical and chemical treatment through portable sewage treatment facilities during construction. In addition, we would like to review the adequacy and economic analysis of calculating environmental conservation costs for physicochemical treatment through portable sewage treatment facilities and sewage treatment generated during construction.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.41 no.2
• /
• pp.26-34
• /
• 2023

This study conducted interviews with former and current managers of Cheongwadae landscape architecture to provide basic information necessary to preserve, manage, and utilize Gyeongbokgung Palace's back garden, and the main conclusions summarized are as follows. First, the topography changed a lot with the construction of the main building and the official residence under President Roh Tae-woo. The water system was connected to Gyeongbokgung Palace in the past, but is now disconnected. Second, in the case of planting, the most important principles were the president's security and protocol, and accordingly, trees were placed or managed. Trees were planted by introducing excellent trees in various regions, and wildflowers and ground cover plants were frequently replaced according to the season. Third, facilities and roads were arranged for the president's protocol, hobbies, and workers' rest, and fire-fighting facilities were installed to prevent disaster in the forest area of Baegaksan Mountain. Fourth, the biggest inflection point of Gyeongbokgung Palace's back garden during Cheongwadae period was the change in topography due to the new construction of the main building and official residence during President Roh Tae-woo, the removal of A and B barbed wire fences that separated space during President Roh Moo-hyun, and the extensive landscaping carried out for the G20 Summit under President Lee Myung-bak. The area of Gyeongbokgung Palace's back garden is expected to face another inflection point due to the opening of Cheongwadae on May 10, 2022, and the work of evaluating the historical, academic, and landscape values of Gyeongbokgung Palace's back garden should be carried out while preserving the status.

• Journal of the Korea Society of Computer and Information
• /
• v.28 no.8
• /
• pp.103-109
• /
• 2023

In this paper, we propose a smart wall switch based on IEEE 802.11b/g/n standard 2.4GHz band communication. As the 4th industrial era evolves, smart home solution development is actively underway, and application cases for smart wall switches are increasing. Most of the Chinese products that preoccupy the market through price competitiveness use Bluetooth and Zigbee communication switches. However, while ZigBee communication is low power, communication speed is slower than Bluetooth and network configuration through a separate hub is additionally required. The Bluetooth method has problems in that the communication range and speed are lower than Wi-Fi communication, the communication standby time is relatively long, and security is weak. In this study, an IEEE 802.11b/g/n smart wall switch applied with Wi-Fi communication technology was developed. In addition, through the two-wire structure, it is designed so that no additional cost is incurred through the construction of a separate neutral line in the building. The result of the study is more than 30% cheaper than the existing wall switch, so it is judged that it will be able to preoccupy the market not only in terms of technological competitiveness but also price competitiveness.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.4
• /
• pp.39-51
• /
• 2019

This study was tested on Ratafia Champagne Trouillard 1947 of old fortified wine and analyzed differences from existing wines. Old fortified wine in Champagne, France and blanding is Pinot Noir, Chardonnay and Pinot Meunier. Alcohol level is 18% and test date is Feb. 15-21, 2019(six days of decanting period/15 p.m. on the last tasting day). Tester is composed of one FICB grand commander one KOV Finland commander. The wine opening was tested for two blades after wire removal and the decanting time was applied to the calculation formula of 2019(this year)-1947(vintage year)/12=6 days set in this study. Aroma smelled like cherries, fruits, soy sauce and licorice and bouquet was identified in five stages. The first stage was presented with the smell of pot, the second stage was light coffee, the third stage smell of fruit and flowers, the fourth stage smell of wild honey and the fifth stage smell of refined brandy. Then, the test was analyzed in seven stages. This study has the following implications: First, the new concept of old wine was applied to fortified wine. Specific computational formulas for the decanting period were derived. The decanting presented five steps of aromas and bouquet. Wine testing has been expanded from the previous five to seven levels. A new taste of Champagne old fortified wine was analyzed.

• Journal of the Korean Geotechnical Society
• /
• v.23 no.10
• /
• pp.5-11
• /
• 2007

This paper is to investigate the removal of the smear at elevated temperatures. This study utilized both small cylinder cell and large consolidometer apparatus to investigate the combination of PVD with heat and without heat. Two types of heaters are used in this study. The heater drain made of copper tube is used for all tests except large consolidometer and flexible wire heater is used for large consolidometer. Specimens demonstrated volume contraction upon heat and without heat. This contraction is dependent on temperature magnitude. When the specimen is heated, the magnitude of settlements is higher and rate of consolidation is faster. After treatment using PVD combined without heat and with heat for undisturbed specimens the $C_h$ values obtained were $3.45m^2/yr$ and $3.83m^2/yr$, respectively, from $3.2m^2/yr$ before treatment. The $K_h/K_s$ ratios were 3 for the specimen without heat and 2 for the specimen with heat. Similarly, in reconstituted specimens without heat and with heat, the $C_h$ values were $2.1m^2/yr$ and $2.5m^2/yr$ with $K_h/K_s$ ratios of 1.75 and 1.5, respectively.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.22 no.2
• /
• pp.107-116
• /
• 2022

Background: Pain during fixed orthodontic treatment can have a detrimental effect on patient treatment compliance. To overcome this, there is a definite need to establish the best pain-relieving methods suitable for orthodontic patients in terms of efficacy and use. The objective of this study was to compare the effect of chewing gum and pre-emptive tenoxicam on pain after initial archwire placement and to evaluate the pain perceptions of orthodontic patients in the two groups while performing various functions at specific time intervals. Methods: Forty-two patients were selected and randomly divided into two groups: group A (chewing gum) and group B (pre-emptive tenoxicam). Pain perception was documented by patients immediately; at 4 h; at bedtime on the day of archwire placement; the next morning; at 24 h; and at bedtime on the 2nd, 3rd, and 7th day after the initial archwire placement. Pain scores were noted during fitting of the posterior teeth, biting, and chewing using a visual analog scale. The data obtained were subjected to statistical analysis. Results: Group A showed a significant increase in pain until the next morning while fitting the posterior teeth, biting, and chewing [36.2, 52.0, 33.4, respectively]], followed by a gradual decrease by the 7th day. Group B showed a significant increase in pain at bedtime on biting, with a peak value of 47.5. Pain on chewing, fitting posterior teeth, peaked the morning of the next day (100.0, 45.0). The Freidman test showed a statistically significant difference with a p-value of < 0.01. Higher pain scores were observed while chewing and biting compared with that while fitting the posterior teeth in both groups. The overall comparison of pain control between the two groups was not statistically significant [P > 0.05] between the two groups. Conclusions: Chewing gum was not inferior to pre-emptive tenoxicam. Thus, chewing gum is a non-pharmacological alternative to analgesics for orthodontic pain control that eliminates the chance of adverse reactions and can be used in the absence of adult observation.

• Advanced Industrial SCIence
• /
• v.2 no.2
• /
• pp.9-15
• /
• 2023

Since silicone rubber heaters are flexible, they can be directly attached or installed in objects to be heated even in flat, curved or three-dimensional shapes. Since the current heating method heats the entire object to be heated and raises it to a required temperature, ignoring areas or positions where heat is not required, partial intensive heating cannot be performed. When using multi-heating zones, rather than heating the entire object to be heated, only the parts that need heat are intensively heated according to the process, so it is possible to heat quickly by local location by applying different amounts of heat with a small amount of electric capacity to each place that needs heat, and heat energy can reduce. In this study, the temperature and heating time of the partially concentrated region in the multi-heating region structure are measured so that a uniform temperature or temperature difference occurs in the region requiring thermal fusion. In order to determine the optimal power density range and reduce capacitance, the safety of a silicon rubber heater manufactured with a multi-heating zone structure is investigated. If the silicon rubber heater is manufactured in a multi-heating method, the multi-intensive heating technology can be ideally applied to all heating processes.