• Fashion & Textile Research Journal
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• v.2 no.5
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• pp.411-415
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• 2000

To be able to work safely and efficiency, the Threshold Limit Values (TLV) for work in the heat are widely used. Since these TLV are only applicable to workers in regular clothing, TLV should be adjusted when applied to the asbestos removal workers who wear extra impermeable protective clothing. Although abbreviated guidelines for heat stress exposure have been proposed, literature advocating their use in the asbestos removal industry is limited. Therefore, we planed a survey to evaluate the workload of asbestos abatement workers in summer, and an experiment with climatic chambers to evaluate the effects of resting in a cool environment between work periods. From these studies, we got following conclusions. There is a high risk of suffering from heat illness by asbestos abatement work in summer in Japan. It is proposed to create a cool room inside the workplace of asbestos abatement work to reduce thermal stress.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.4
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• pp.387-394
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• 2016

Today, hot rolled mill plant are currently operating 24 hours a day. The main processes of hot-rolled steel mill are Reheating Furnace, Roughing Mill, Fishing Mill and the Down Coiler. In the process checking over the thickness and width of rolled material, temperature control is an important factor. It is quite often the cause of the work breakdown and find a bad elements for product. After the shipping out the product, when a claim occurs requires an investigation. In each process of the conventional thickness gauge, width, and thermometer. Operation by an independent data acquisition and this monitoring is problematic and straining of the operator. The monitoring process the data of each function and incorporate monitoring results can also check future work. The installation of this system will improve our efficiency and productivity. In the rolling process by developing more efficient operating quality monitoring system, this will be made possible.

• Safety and Health at Work
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• v.14 no.4
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• pp.457-466
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• 2023

Background: During hot environment work tasks with whole-body enclosed anti-bioaerosol suit, the combined effect of heavy sweating and exhaled hot humid air may cause the N95 medical respirator to saturate with water/sweat (i.e., water-blocking). Methods: 32 young male subjects with different body mass indexes (BMI) in whole-body protection (N95 medical respirator + one-piece protective suit + head covering + protective face screen + gloves + shoe covers) were asked to simulate waste collecting from each isolated room in a seven-story building at 27-28℃, and the weight, inhalation resistance (R_f), and aerosol penetration of the respirator before worn and after water-blocking were analyzed. Results: All subjects reported water-blocking asphyxia of the N95 respirators within 36-67 min of the task. When water-blocking occurred, the R_f and 10-200 nm total aerosol penetration (P_t) of the respirators reached up to 1270-1810 Pa and 17.3-23.3%, respectively, which were 10 and 8 times of that before wearing. The most penetration particle size of the respirators increased from 49-65 nm before worn to 115-154 nm under water-blocking condition, and the corresponding maximum size-dependent aerosol penetration increased from 2.5-3.5% to 20-27%. With the increase of BMI, the water-blocking occurrence time firstly increased then reduced, while the R_f, P_t, and absorbed water all increased significantly. Conclusions: This study reveals respirator water-blocking and its serious negative impacts on respiratory protection. When performing moderate-to-high-load tasks with whole-body protection in a hot environment, it is recommended that respirator be replaced with a new one at least every hour to avoid water-blocking asphyxia.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.129-133
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• 2001

A finite element-based, integrated process model is presented for a three dimensional, coupled analysis of the thermo-mechanical behavior of the strip and work roll in the continuous hot strip rolling. The validity of the proposed model is examined through comparison with measurements. The effect of Edge-Heater on the finishing delivery temperatures is examined by using the present model. The models capability of revealing the effect of diverse process parameters is demonstrated through a series of process simulation.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.12
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• pp.53-58
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• 1991

Hot-carrier induced degradation has been studied for the BF$_2$ ion-implanted surface-channel LDD(P$^{+}$ polysilicon gate) PMOSFET in comparison to the buried-channel structure(N$^{+}$ polysilicon gate) PMOSFET. The conditions for maximum degradation better correlated to I$_{g}$ than I$_{sub}$ for both PMOSFET's. Due to the use of LDD structure on SC-PMOSFET, the substrate current for SC-PMOSFET was shown to be smaller than that of BC-PMOSFET. The gate current was smaller as well, due to the gate material work-function difference between p$^{+}$ and n$^{+}$ polysilicon gates. From the results, it was shown that the surface-channel LDD PMOSFET is more resistant to short channel effect than the buried-channel PMOSFET.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.614-618
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• 2002

In hot strip mills, Portable Roll Scanner (the portable roll surface temperature and profile measuring device) can be used to calibrate on-line Process models for strip crown and flatness by measuring the thermal expansion and wear profile of the rolls. And the surface temperature measurement can be used to optimize the roll cooling system. Portable Roll Scanner consists of the measuring device, which has two contact inductive distance transducers for roll profile measurement and one infrared Pyrometer for surface temperature measurement, and computer-based controller that is equipped with the measuring device. By the wireless data communication, the data is transferred to the memory of notebook for further analysis. After roll extraction from mills, Portable Roll Scanner measure the roll profile and surface temperature simultaneously along the work roll face and display the results in the TFT color monitor of notebook. Portable Roll Scanner is useful at mill-side and roll grinding shop.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.5
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• pp.327-333
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• 2011

In the present work, a new freeze protection method has been proposed for a natural circulation system of solar water heater. Though electrothermal wire is popularly used for the purpose, there are freezing troubles by wire cut-off and shortage of excessive electric power consumption. In the experimental device, hot water in storage tank was used to heat the outlet pipe from the tank if the pipe surface temperature falls lower than a set point. The cold water pipe to the storage tank was installed to directly contact the hot water pipe surface temperature rose by transferred heat.

• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.147-150
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• 1992

In general, hot nodules on techetium scan are regarded as benign tumors, and usually no further work up for malignancy is indicated, if they are truly autonomous. The authors experienced two cases of thyroid carcinoma presenting as hot nodule on technetium-99m pertechnetate thyroid scintigraphy. One case with papillary carcinoma, and other case with follicular carcinoma are presented in addition to a review of the literature.

• 전자공학회논문지 IE
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• v.45 no.2
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• pp.1-5
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• 2008

In this work, RF performance degradation due to hot carrier effects in SOI MOSFET have been measured and analyzed. The LNA that designed at $V_{GS}=0.8V$, f=2.5GHz, gain is 16.51dB and noise figure is 1.195dB. After stress at SOI, the LNA's gain and noise figure change of 15.3dB and 1.44dB with before stress.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.175.2-175
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• 2001

The strip profile and shape control is one of the most important technologies in Hot Rolling Mill System. Because the unbalance of strip´s shape and wave appearance between stands has a bad effect on Hot Rolling Mill System by making the inferior thickness, strip´s damage and so forth in factories. Many competition Plate Mill introduced shape control system, for example, pair cross-mill, work roll bender, which includes shape measuring instruments and shape control mathematical models. Shape meter, which is equipped for flatness, only does feedback control at the top of coil. And, for crown, we depend on initial setup value and there is no feedback control. Therefore we predict the shape of strip using rolling pressure, bender force and tension of inter-stand in ...