• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.2
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• pp.91-97
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• 2002

The present study concerns an experiment on the supply-air control in variable air volume (VAV) system with a Pl control logic. A thermal chamber with a Pl control logic is constructed to verify the previously suggested multi-zone model. The stratified thermal model is adopted in the control logic for a thermal chamber cooling test. The effects of taler- mal parameters and control parameters such as supply air temperature and Pl control factor are investigated by implementing the thermal chamber cooling test. The experimental results obtained show that the transient behavior of the air-conditioned space temperature are in good agreement with the simulation results of the stratified thermal model.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.9 no.14
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• pp.35-43
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• 1986

PL(product liability) is a major social, market, and economic force. The legal obligation of manufacturers and sellers to compensate for injury or damage caused by defective products is not a recent phenomenon. The concept of Product liability has been in existence for many years, but its emphasis has changed recently. This PL prevention program has shown that the two area of product quality assurance one is a PLD(product liability defense) and the other is a PLP(product liability prevention.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.596-608
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• 2017

In 2002, the government arranged an institutional strategy to make it possible for a consumers to make a claim for damages caused by product defects against a business that produces and sells a product by enforcing the Product Liability Law(hereinafter referred to as 'PL'). On the other hand, due to the recent humidifier sterilizer accident, approximately 12 cases of related bills, such as a revised bill for the product liability law, have been proposed to the National Assembly at present in an effort to introduce the group action system and punitive compensation system for the purpose of the strengthening of the corporate product liability, and consumer damage relief. Ironically, as much as 62.6% of small & medium businesses, which are actual interested parties to this bill, are unaware of this. Many companies are responding to PL with the rationalization of document preparation & storage, clarification of responsibility relations with related business operators, and PL insurance policy purchase, or securing compensation funds as a means of Product Liability Defense(PLD), but the methods of preparation such as this leave much room for limits on the considerations of product design and product safety. This paper presents the individual management system model with more focus on product safety by looking into the clear concept of PL and the countermeasures against it, grasping the relevance between the PL system and individual management system, and integrating the PL response system in preparation for the PL. It is hoped that the result of this research objective will be evaluated as a rational countermeasure for small & medium businesses to respond effectively to the PL.

• Journal of the Korean Vacuum Society
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• v.22 no.6
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• pp.321-326
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• 2013

The effect of rapid thermal annealing (RTA) on the optical properties of digital-alloy InGaAlAs multiple quantum well (MQW) structures have been investigated by using photoluminescence (PL) and time-resolved PL measurements as a function of RTA temperature. The MQW samples were annealed from $700^{\circ}C$ to $850^{\circ}C$ for 30 s in a nitrogen atmosphere. The MQW sample annealed at $750^{\circ}C$ exhibited the strongest PL intensity and the narrowest FWHM (Full width at half maximum), indicating the reduced nonradiative recombination centers and the improved interfaces between the wells and barriers. The MQW samples annealed at $800^{\circ}C$ and $850^{\circ}C$ showed the decreased PL intensities and blueshifted PL peaks compared to $750^{\circ}C$-annealed sample. The blueshift of PL peak with increasing RTA temperatures are ascribed to the increase of aluminum due to intermixing of gallium (Ga) and aluminum (Al) in the interfaces of InGaAs/InAlAs short-period superlattices. The decrease of PL intensity after annealing at $800^{\circ}C$ and $850^{\circ}C$ are attributed to the interface roughening and lateral composition modulation caused by the interdiffusion of Ga and Al and indium segregation, respectively. With increasing RTA temperature the PL decay becomes slower, indicating the decrease of nonradiative defect centers. The optical properties of digital-alloy InGaAlAs MQW structures can be improved significantly with optimum RTA conditions.

• Korean Journal of Materials Research
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• v.8 no.4
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• pp.359-361
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• 1998

Visible photoluminescence(PU was observed from hydrogenated amorphous silicon deposited on silicon(a-Si : H/Si) using electron cyclotron resonance plasma enhanced chemical vapor deposition (ECR- PECVD) with silane ($SiH_{4}$) gas as the reactant source. The PL spectra from a-Si : H/Si were very similar to those from porous silicon. Hydrogen contents of samples annealed under oxygen atmosphere for 2minutes at $500^{\circ}C$ by rapid thermal annealing were reduced to 1~2%, and the samples did not show visible PL, indicating that hydrogen has a very important role in the PL process of a- Si : H/Si. As the thickness of deposited a-Si : H film increased, PL intensity decreased. The visi¬ble PL from a-Si: H deposited on Si by ECR-PECVD with $SiH_{4}$ . is suggested to be from silicon hydrides formed at the interface between the Si substrate and the deposited a-Si : H film during the deposition.

• Proceedings of the Safety Management and Science Conference
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• 2008.04a
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• pp.383-387
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• 2008

Nowadays, the tendency of world air cargo is noteworthy and air traffic in terms of cargo throughput will no doubt grow significantly in the new Region, with India and China's booming economy and the upcoming Olympics 2008. For example, in the first 11 months of 2006 cargo traffic was increased by 6.3%. First of all, the market of air cargo in Korea grows very quickly and diversifies. It is an essential factor in the process of development of Northeast-Asia as a hub for Air Cargo logistics. However the process of air cargo in Korea is complex as compared with other north-east asia nations. At the same time, it has many problems and causes inconvenience to owners of freight. This paper investigated the process of air cargo in Korea now and analyzed problems of the process. We emphasize that 4PL is the excellent solution from among many alternatives. It is also worthy of notice that EPCglobal network strengthen the role of 4PL. In conclusion, the 4PL system based on EPCglobal network will result in a good success, so it will raise a prestige of air cargo in Korea to a higher position.

• Journal of the Korean Vacuum Society
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• v.22 no.2
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• pp.92-97
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• 2013

The luminescence properties of InAs/GaAs quantum dots (QDs) grown by a migration enhanced epitaxy method have been investigated by using photoluminescence (PL) and time-resolved PL measurements. The MEE method supplies materials in a series of alternate depositions with migration enhancing time between each deposition. After In source was supplied for 9.3 s, the growth was interrupted for 5 s. Subsequently, As source was open for 3 (AT3), 4(AT4), 6 (AT6), or 9 s (AT9), and the growth was interrupted for 5 s again. This growth sequence was repeated 3 times for the growth of InAs QDs. The PL peak of the AT3 was 1,140 nm and the PL intensity was very weak compared with that of the other three samples. The PL peak of all samples except the AT3 sample was 1,118 nm, which is blueshifted from 1,140 nm, and the PL intensity was increased compared to that of the AT3. These results can be explained by the increased QD density and the improved QD uniformity. The AT6 sample showed the strongest PL intensity and the narrowest full width at half maximum. The PL decay time of AT6 increased with increasing emission wavelength from 940 to 1,126 nm, reaching a maximum decay time of 1.09 ns at 1,126 nm, and then decreased as the emission wavelength was increased further.

• The monthly packaging world
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• s.110
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• pp.104-109
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• 2002

• The monthly packaging world
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• s.110
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• pp.56-62
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• 2002

• Product Safety
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• s.121
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• pp.44-47
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• 2004