• 반도체디스플레이기술학회지
• /
• 제18권4호
• /
• pp.124-128
• /
• 2019

In this paper, a high temperature plastic film type water level sensor was developed. The high temperature film type water level sensor was manufactured by attaching a copper film to a polyimide film which can be used for a long time at 250℃, by laminating process and patterning the electrode by etching process. For the performance evaluation of the developed film type water level sensor, the temperature dependence of the capacitance was measured, and the deformation was examined after standing for 8 hours in 150℃ air. The developed film type water level sensor can be used at up to 150℃, and can be applied to electric ports and steam devices.

• 한국컴퓨터정보학회논문지
• /
• 제24권1호
• /
• pp.129-135
• /
• 2019

This paper is part of research and development for stand-alone solar system without commercial power supply. It implements firmware of controller for operation of stand-alone solar system by applying IoT technology and also develops communication modules that allow multiple solar lamps to send and receive data through wireless network. The controller of the developed stand-alone solar system can effectively charge the power generated by the solar module, taking into account the battery's charge and discharge characteristics. It also has the advantage of attaching wireless communication modules to solar lamp posts to establish wireless communication networks without incurring communication costs. In addition, by establishing IoT gateway middleware platform for each installation site, it forms a foundation to operate multiple solar lamp posts into multiple clusters. And, it is expected that the data collected in each cluster will be used to enable configuration and control of operational information, thereby inducing convenience and efficiency of remote operation and management.

• 대한안전경영과학회지
• /
• 제20권4호
• /
• pp.15-19
• /
• 2018

The purpose of this study is to enhance heat insulation effect and to decrease fire hazard by attaching aluminum foil to expanded polystyrene, which is mainly used for insulating materials, to have fire retardant. The result of the test confirmed that the insulating materials, expanded polystyrene of $10kg/m^3$ and $14kg/m^3$ of density attached aluminum foil on both sides, showed 12%, 14% of improved heat transfer coefficient respectively compared to existing expanded polystyrene of the same density. Besides, they met all the standards for the testing of heat release and gas hazard. On the other hand, the one made of general expanded polystyrene could not meet the standards of the heat release test and the gas hazard test.

• Bulletin of the Korean Chemical Society
• /
• 제17권2호
• /
• pp.168-172
• /
• 1996

The variations of the structural detail of layered perovskite-type oxides, Na2Ln2Ti3O10 (Ln=La, Nd, Sm, Gd), have been refined by Rietveld analyses of their powder X-ray diffraction data. Although the c-axis strongly decreases from Ln=La to Nd, Sm, or Gd, the length of Na-O bond along the c-axis that is regarded as the sodium layer spacing is not dependent on the unit cell parameter. Such a behavior is explained by the fact that Na-O bond is in competition with Ti-O one of the perovskite slab. Increased covalency of this Ti-O bond by the lattice contraction leads to weakening of the attaching strength of Na ion. This picture is consistent with the experimental observation that Na ion conductivity of Na2Ln2Ti3O10 increases from Ln=La to Nd, Sm, or Gd despite strong contraction of the unit cell volume.

• 센서학회지
• /
• 제30권1호
• /
• pp.42-46
• /
• 2021

In this paper, we describe the development of a force sensor to measure the tool gripping force of the BT50 spindle. The force sensor for a BT50 must be installed inside the gripping force tester; hence, it must be of an appropriate size and have a rated capacity suitable for measuring the gripping force. So, the structure of the force sensor for BT50 was modeled, the size of the sensing part was determined by structural analysis, and the force sensor was manufactured by attaching a strain gauge. The characteristic test results of the manufactured force sensor, indicated that the nonlinearity error, hysteresis error, and reproducibility errors were each within 0.91%, Therefore it was determined that the manufactured force sensor can be used for checking the spindle tool gripping force.

• International Journal of Computer Science & Network Security
• /
• 제22권1호
• /
• pp.189-198
• /
• 2022

As the number of people using the Internet increases, a new application known as the Internet of Things (IoT) has been emerged. Internet of Things makes it easier for machines and objects to exchange, compute, and coordinate information autonomously without human interference. It is a tool for attaching intelligence to a variety of contemporary objects in houses, hospitals, buildings, vehicles, and even cities. As a new emerging technology, the focus in current IoT surveys does not shed the light on deep understanding for IoT fundamentals, architectures, challenges, and solutions. For this reason, the objective of this paper is to introduce specifications for IoT definitions, characteristics, functional blocks, and different architectures as a cement for better understanding. Additionally, we present current documented IoT challenges, with the existing available solution for each challenge.

• 전자통신동향분석
• /
• 제37권1호
• /
• pp.10-20
• /
• 2022

A drone without attaching guns or bombs can be a dangerous weapon, since its motor speed is greater than 3000 rpm, which is similar to that of a mower powered by a LiPo battery. The anti-drone system is the only means of detecting and neutralizing drone attacks. Many defense companies around the world provide solutions using various types of equipment (for example, radar, cameras, jamming guns, and net guns). ETRI has also developed a Low-Altitude Drone Detection (LADD) system consisting of Ku-band radar and an Electro-Optical/Infra-Red (EO/IR) camera. In this paper, we summarize recent technical advances in anti-drone systems around the world and introduce the features and describe the performance of the LADD system.

• Animal Systematics, Evolution and Diversity
• /
• 제38권4호
• /
• pp.242-247
• /
• 2022

In 2021, during a survey of cnidarian fauna around Geomundo located in the Dadohaehaesang National Park in the South Sea, complete pinnated hydroid colonies attaching on vertical rocky surface at depth of 45 m were collected by SCUBA diving. Through taxonomic examination, unrecorded species, Sertularella acutidentata Billard, 1919, is newly added to the hydrozoan fauna of Korea. Recently, taxonomic position of the genus Sertularella has been relocated into the new family Sertularellidae Maronna et al., 2016 and six species from Korean waters have been synonymized or transferred to new genera. Thus, a total of 17 species belonging to genus Sertularella, including the species reported in this study, have been reported in Korean waters so far.

• 셀메드
• /
• 제12권4호
• /
• pp.16.1-16.2
• /
• 2022

Treatment of patients with pain is directed at relieving pain and restoring function. Heat therapy has been used as a pain treatment. The mean temperatures were 40 and 41℃. Our device, Dr.Pakk heats special silicone to 41℃ with far-infrared rays and attaches it to the painful knee using a vacuum to show the effect. The core technology of the Dr.Pakk is that deep heat is generated when the heat is transmitted deeply by attaching it to the skin. In our experience, Dr.Pakk can be especially effective for knee pain.

• 한국지반환경공학회 논문집
• /
• 제23권9호
• /
• pp.25-31
• /
• 2022

Attaching shelf to retaining structure leads to a decrease in the total lateral earth pressure. This decrease enables the retaining structures to become more stable, to have small displacement, and to exhibit lower bending moments, the relief shelves effects are analyzed using FEM in order to understand how they stabilize cantilever wall in this study. Several models are varied by changing location and width of shelves to realize earth pressure and displacements of retaining wall. The displacement is getting smaller because earth pressure acting on shelf increases as shelves locations are lower and width is longer. The ground settlement variation effects caused by relief shelves are studied also. The ground settlement increases abruptly where shelf location is between of 0.5H and 0.625H, and settlement decreases suddenly where shelf width is between b/h=0.375 and b/h=0.500. The shelf significantly reduces earth pressure and movement of the wall. This decrease in the lateral pressure increases the retaining structure stability.