• Journal of Korean Clinical Health Science
• /
• v.9 no.1
• /
• pp.1462-1468
• /
• 2021

Purpose; The purpose of this study is to objectively identify and quantify the wearer's feelings of wearing glasses. Methods: The temperature of the skin on the nose ridges and ear, and the area where the glasses were seated, was measured using a thermal imaging camera. Results: Before wearing the glasses, the temperature of the skin surface on the nasal ridge was 34.908 ± 0.875 ℃ and the temperature of the ear region was determined as 31.981 ± 0.549 ℃. The changed temperature measured at 5 minutes later after taking off the glasses showed that the nasal ridge was determined as 35.467 ± 0.342 ℃ and the ear area was determined as 32.994 ± 0.412 ℃ (p<0.05). Conclusions: In this experiment, it was revealed that the glasses cause discomfort and heat in the fitting area. It was the first attempt to study objectively and scientifically. Analysis of frame fitting points by using thermal camera is expected to be helpful when consulting a sensitive person about changes in the fit of glasses.

• Journal of the Korean Institute of Gas
• /
• v.16 no.6
• /
• pp.102-106
• /
• 2012

The purpose of this paper is to study the failure cases in relation to system of Air Bag in vehicle happened in the field. In the first example, it was separated the soldering parts connected the wire pin between air bag module and clock spring of air bag. Whenever the pin shake by the car's vibration, the driver verified the malfunction phenomenon appeared air bag warning lamp on instrument panel in front of driver's seat. in car inside room. The second example, it verified the warning lamp lighting phenomenon of air bag by produced the circuit plate non-contacting of single an element in air bag electronic control unit. The third example, it verified the light of air bag warning indicator lamp by separated with soldering parts connecting inner pin and resistance terminal of seat belt pretensioner using passenger seat. The fourth example, when the passenger car crash a back of truck, the former bumper get jammed under the latter as the roof height of car low less than that. Therefore, the impact of Car's collision verified that don't transfer with body frame of vehicle because of no attachment impact sensor in it.

• KIISE Transactions on Computing Practices
• /
• v.21 no.8
• /
• pp.524-530
• /
• 2015

A log is for text monitoring and perceiving the issues of a system during the development and operation of a program. Based on the log, system developers and operators can trace the cause of an issue. In the development phase, it is relatively simple for a log to be traced while there are only a small number of personnel uses of a system such as developers and testers. However, it is the difficult to trace a log when many people can use the system in the operation phase. In major cases, because a log cannot be tracked, even tracing is dropped. This study proposed a simplified tracing of a log during the system operation. Thus, the purpose is to create a log on the run time based on an ID/IP, using features provided by the Logback. It saves an ID/IP of the tracking user on a DB, and loads the user's ID/IP onto the memory to trace once WAS starts running. Before the online service operates, an Interceptor is executed to decide whether to load a log file, and then it generates the service requested by a certain user in a separate log file. The load is insignificant since the arithmetic operation occurs in a JVM, although every service must pass through the Interceptor to be executed.

• Journal of the Korean Institute of Gas
• /
• v.24 no.5
• /
• pp.20-28
• /
• 2020

In this study, the damage impact range in the case of a hydrofluoric acid leak accident was predicted using formula calculation, impact assessment simulations, and CFD simulations, and the results were compared and analyzed with the actual environmental impact report. Formula calculation was performed by using the leak source model and diffusion model. Impact assessment simulation was performed by KORA provided by the Korean Ministry of Environment, ALOHA by the United States Ministry of Environment, and PHAST, which is relatively widely used among commercialization programs, and the STAD-CMM+program for CFD simulation. Was utilized. Considering convenience, speed, acceptability, and economics from the user's perspective, ALOHA and KORA were the most appropriate methods for predicting the impact of hydrofluoric acid leakage. In addition, the results of this study will help to reduce unnecessary regulations in the process of government policy development and optimize the investment in the safety field of the company, effectively utilizing the limited resources of the government and the company.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.10
• /
• pp.1211-1222
• /
• 2011

It is necessary to use prestressed modal analysis to calculate the modal frequencies and mode shapes of a prestressed structure such as a spinning blade, a preloaded structure, or a thermally deformed pipe, because the prestress effect sometimes causes significant changes in the frequencies and mode shapes. When the finite element model under consideration has a very large number of degrees of freedom, repeated prestressed modal analyses for investigating the prestress effects might become too computationally expensive to finish within a reasonable design-process time. To alleviate these computational difficulties, a Krylov subspace-based model order reduction, which reduces the number of degrees of freedom of the original finite element model and speeds up the necessary prestressed modal analysis with the reduced order models (ROMs), is presented. The numerical process for the moment-matching model reduction is performed directly on the full order models (FOMs) (modeled in ANSYS) by the Arnoldi process. To demonstrate the advantages of this approach for performing prestressed modal analysis, the prestressed wheel and the compressor impeller under their high-speed rotation are considered as examples.

• Journal of KIISE
• /
• v.43 no.7
• /
• pp.820-826
• /
• 2016

There is a growing requirement for big data processing which extracts valuable information from a large amount of data. The Hadoop system employs the MapReduce framework to process big data. However, MapReduce has limitations such as inflexible and slow data processing. To overcome these drawbacks, SQL query processing techniques known as SQL-on-Hadoop were developed. Apache Tajo, one of the SQL-on-Hadoop techniques, was developed by a Korean development group. External merge sort is one of the heavily used algorithms in Tajo for query processing. The performance of external merge sort in Tajo is influenced by two parameters, sort buffer size and fanout. In this paper, we analyzed the performance of external merge sort in Tajo with various sort buffer sizes and fanouts. In addition, we figured out that there are two major causes of differences in the performance of external merge sort: CPU cache misses which increase as the sort buffer size grows; and the number of merge passes determined by fanout.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.25 no.7
• /
• pp.946-954
• /
• 2021

Since COVID19 virus has been occured, variety steps of the quarantine guidelines were enacted. In step 2.5, eating in a cafe was prohibited and only takeout was permitted, but the government has changed several rules. So now people can have a dissert or coffee in the cafe. Though the government adviced available staying time as 1 hour, it is not obeyed often except superstore, and even the management depends on handwriting. In this paper, we implemented a blockchain system to use for this case. This system is implemented with using hyperledger fabric, the blockchain framework which is made by IBM. For a test, 1 organization is in the system and chaincode is installed to the organization to run the system. We expect the certain effect to the quarantine via this system. Moreover, we will develop an application by using this system as a backend.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.4
• /
• pp.101-109
• /
• 2009

An encryption module is equipped basically at 8i version ideal of Oracle DBMS, encryption module, but a performance decrease is caused, and users are restrictive. We analyze problem of DB security by technology by circles at this paper whether or not there is an index search, object management disorder, a serious DB performance decrease by encryption, real-time data encryption beauty whether or not there is data approach control beauty circular-based IP. And presentation does the comprehensive security Frame Work which utilized the DB Masking technique that is an alternative means technical encryption in order to improve availability of DB security. We use a virtual account, and set up a DB Masking basis by security grades as alternatives, we check advance user authentication and SQL inquiry approvals and integrity after the fact through virtual accounts, utilize to method as collect by an auditing log that an officer was able to do safely DB.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.47 no.1
• /
• pp.58-68
• /
• 2010

In this paper, we propose an efficient link protection switching scheme for provider backbone bridge systems with a spanning tree for backup links exclusively, and evaluate its performance. The proposed scheme offers guaranteed QoS flows even when a link fault occurrs in the primary link by flooding the flows over the profiled spanning tree. The flooding mechanism over the spanning tree can also provide low latency and remove the loopback flows. We also derive the efficiency of bandwidth usage for the normal flows and the number of lost frames during the link restoration. For evaluating its feasibility, we implement a prototype of PBB-TE systems based on the Linux bridge codes, which can support both link protection switching capability with CCM and MAC-in-MAC encapsulation. A related protocol analyzer is also developed. One can see that the proposed scheme and the prototype can be useful for developing carrier class Ethernet systems based on PBB-TE.

• Economic and Environmental Geology
• /
• v.35 no.1
• /
• pp.13-23
• /
• 2002

The chemical compositions of groundwaters from the granite areas mainly belong to Ca-HC0$_{3}$ and Na-HC0$_{3}$type, and some of these belong to Ca-(CI+S0$_{4}$) and Na-(CI+S0$_{4}$) type. Spring waters and groundwaters from anorthosite areas belong to Ca-HC03 and Na-HC03 type, respectively. The result of reaction path modeling shows that the chemical compositions of aqueous solution reacted with granite evolve from initial Ca-CI type, via CaHC0$_{3}$ type, to Na-HC0$_{3}$ type. The result of rain water-anorthosite interaction is similar to evolution path of granite reaction and both of these results agree well with the field data. In the reaction path modeling of rain watergranite/anorthosite reaction, as a reaction is progressing, the activity of hydrogen ion decreases (pH increases). The concentrations of cations are controlled by the dissolution of rock-forming minerals and precipitation and re-dissolution of secondary minerals according to the pH. The continuous addition of granite causes the formation of secondary minerals in the following sequence; gibbsite plus hematite, Mn-oxide, kaolinite, silica, chlorite, muscovite (a proxy for illite here), calcite, laumontite, prehnite, and finally analcime. In the anorthosite reaction, the order of precipitation of secondary minerals is the same as with granite reaction except that there is no silica precipitation and paragonite precipitates instead of analcime. The silica and kaolinite are predominant minerals in the granite and anorthosite reactions, respectively. Total quantities of secondary minerals in the anorthosite reaction are more abundant than those in the granite reaction.