• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.9-15
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• 2018

This paper shows the principles and characteristics of the transient liquid phase (TLP) bonding technology for power modules packaging. The power module is semiconductor parts that change and manage power entering electronic devices, and demand is increasing due to the advent of the fourth industrial revolution. Higher operation temperatures and increasing current density are important for the performance of power modules. Conventional power modules using Si chip have reached the limit of theoretical performance development. In addition, their efficiency is reduced at high temperature because of the low properties of Si. Therefore, Si is changed to silicon carbide (SiC) and gallium nitride (GaN). Various methods of bonding have been studied, like Ag sintering and Sn-Au solder, to keep up with the development of chips, one of which is TLP bonding. TLP bonding has the advantages in price and junction temperature over other technologies. In this paper, TLP bonding using various materials and methods is introduced. In addition, new TLP technologies that are combined with other technologies such as metal powder mixing and ultrasonic technology are also reviewed.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.231-236
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• 2022

The research was aimed to improve pre-harvest methods to maintain marketability in postharvest leaf lettuce. In this study, the effect of hydroponics on the growth and post-harvest storage characteristics of 'Chongchima' lettuce grown in peat mass medium hydroponic system using a non-powered culture device or deep water culture (DWC) was evaluated. There was no difference in fresh weight, leaf number, SPAD, moisture content, and C/N ratio between peat moss growing medium hydroponic and DWC methods except plant height. It was found that lettuce cultivation by a nonpowered hydroponics method is easier than the existing DWC. The quality parameters, such as fresh weight loss, SPAD value, and general appearance of lettuce were investigated after harvest. There was no significant difference in fresh weight loss and general appearance during storage of lettuce by the hydroponics methods. However, with the increased storage time of SPAD, which is related to chlorophyll content, was slightly higher in peat moss medium hydroponic was than DWC. When crops such as lettuce are grown under favorable conditions without any agronomic abnormalities, it is suggested that post-harvest storage is not significantly affected by peat moss growing medium hydroponic and DWC.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.151-162
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• 2017

The purpose of this study was to investigate the quality change of fresh-cut tumeric (Curcuma Longa Linne) according to packaging method during storage time. The fresh-cut tumeric were packaged in three different methods : degassing valve packaging (DVP), $CO_2$ gas absorber packaging (CAP) and micro-perforated packaging (MPP). After the samples were packaged, they were stored for 15 days at 4 and $23^{\circ}C$ respectively. The following parameters were observed to indicate the quality changes of the samples: weight loss, CIE $L^*a^*b^*$ colour difference, variation of gas composition inside the package, curcumin contents and changes in hardness of fresh-cut tumeric. DVP did not effectively release $CO_2$ gas to the outside. MPP was suitable to release $CO_2$ gas. However, MPP showed very fast browning and erosion, because a large amount of oxygen was introduced through the perforated hole on the film. CAP was most effective packaging method to inhibit browning, to prevent expansion of the packaging by $CO_2$ gas and to minimize weight loss of fresh-cut tumeric.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.163-171
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• 2017

Effects of different packaging methods for maintaining the shelf life and postharvest quality of iceberg lettuce (Lactuca sativa L.) were studied after harvesting in summer season. Lettuce heads were packaged in plastic crate with or without different films such as (A) Individual lettuce head sealed packaging with linear low density polyethylene (LLDPE) film; (B) Packaging lettuce head in plastic crate and wrapped with LLDPE film; (C): Individual lettuce head sealed packaging with perforated high density polyethylene (HDPE) film; (D) Packaging lettuce head in plastic crate and wrapped with perforated HDPE; and (E) Packaging lettuce head in plastic crate without any film (control), and stored at $2^{\circ}C$ for 35 days. Several quality parameters such as fresh weight loss, SPAD (soil & plant analyzer development) meter value, respiration rate, moisture content and appearance of lettuce were investigated. The lettuce wrapped with individually-sealed LLDPE film showed the lowest weight loss and the highest SPAD value rendering the best appearance index among the treataments throughout the three-week storage period at $2^{\circ}C$. Extending the freshness of iceberg lettuce during low temperature storage will definitely increase the salability potential in the domestic market even during summer season.

• Preventive Nutrition and Food Science
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• v.6 no.4
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• pp.211-215
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• 2001

The packaging effect on physicochemical changes in irradiated sausage stored at -2$0^{\circ}C$ was studied. Emulsion-type cooked pork sausage was made with (156 ppm) or without NaNO$_2$ (0 ppm), and packaged in three different conditions such as aerobic, vacuum and $CO_2$ (100%). The samples irradiated at 0, 5 and 10 kGy absorbed dose, and the total number of microorganisms, lipid oxidation, color and texture were analyzed during frozen storage at-2$0^{\circ}C$. Irradiation of the sausage at 10 kGy completely controlled microbial growth during storage. An NaNO$_2$ addition to the sausage significantly reduced lipid oxidation, and the TBARS value of the sausage with aerobic packaging was higher than that with the vacuum and $CO_2$ packaging. The NaNO$_2$ addition increased Hunter color a-value dramatically, but no packaging effect was found (p > 0.05). Irradiation influenced shear values resulting in lower shear values in 10 kGy-irradiated sausages with aerobic packaging, and $CO_2$ packaged sausage showed comparatively lower shear value than other packaging methods. From the results, vacuum or $CO_2$ (100%) packaging were better than aerobic packaging for frozen stored pork sausage, especially far microbial quality and lipid oxidation.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.2
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• pp.61-65
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• 2015

Agricultural products packaged for transportation are put in the various dangerous environments owing to the damage factors like vibration, shock, compression, climate etc. under the distribution process. On fruits packaging for transportation, especially, the shock and vibration is considered as the most important damage factors. A major cause of shock damage to fruits is drops during manual handling. Especially, the damages of fruits during the parcel delivery service are very serious. The parcel delivery services of fruits are increasing and contribute to increasing of farm house earning. Also, the freight vehicle is mostly used to transport the fruits. Shock and impact generated by the freight vehicle may give serious damage to fruits. The optimum packaging design of parcel delivery service of fruits during transportation is required to reduce the fruits damages. In order to design the packaging system for parcel delivery service of fruits considering the transportation environment, the comprehension of characteristics for vibration and shock generated by manual handling and acting on transportation vehicles under various road conditions and loading methods is required. This research was performed to analyze the shock characteristics, acceleration level and power spectral density (PSD) during the parcel delivery service of fruits. The overall level of recommended PSD profile in a specific transportation of parcel delivery service for fruits was $0.63G_{rms}$.

• Journal of Food Hygiene and Safety
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• v.10 no.2
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• pp.97-102
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• 1995

For improved preservation of boiled-dried anchovies, the current preservation method of corrugated-cardboard box packaging and freezing below -18$^{\circ}C$ was compared to the nylon/polyethylene(NY/PE) packaging along with cooling temperature ranging from 5$^{\circ}C$ to 1$0^{\circ}C$ as well as ambient condition for eight months by determining physicochemical quality of stored samples. Lipid oxidation of stored anchovies and their browning increased with storage time. The phenomenon was delayed under the conditions of lower temperature and air-tight packaging. As quality-indicative criteria of stored anchovies, carbonyl value(r=-0.989), browning (r=-0.949) and color a value(r=-0.989), browning(r=-0.965), Hunter's color b value(r=-0.949) and color a value(r=-0.940) showed a highly-negative correlations with organoleptic qualities of the samples. Based on the above results, air-tight packaging in a laminated film and subsequent storage at cooling temperature was found to be a possible alternative to the current freezing-storage of boiled-dried anchovies from the physicochemical point of view.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1043-1047
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• 2002

This study was carried out to investigate the effect of packaging materials (Ny/PE, PET/Al/PE, PET/PE/LDPE/CPP, PET/Al/Ny/CPP films, and bottle) and packaging methods (atmosphere and vacuum) on the physicochemical properties of Onion Kimchi and Rosemary-onion Kimchi stored at $5^{\circ}C$. Reducing sugar contents and pHs of Onion Kimchi and Rosemary-onion Kimchi decreased, whereas levels of titratible acidity and vit C contents increased with increasing the storage time. The fermentation of Rosemary-onion Kimchi was slower than that of Onion Kimchi. PET/PE/LDPE/CPP film was the most effective for Onion Kimchi packaging among all packaging materials tested.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.2
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• pp.127-132
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• 2022

The growth of e-commerce market requires more delivery packagings, which protect goods from the damage factors on the delivery. In this study, we have analyzed the distribution environment data (vibration and impact) measured in previous study and compared with global standards (ISTA, ASTM), so that we developed the testing method for Field-to-Lab simulation suitable to the domestic delivery. In order to verify the efficacy of this method, we took the Field-to-Lab tests for 3 packaged products (detergents set, glass tableware set, small furniture), which has been frequent breakages or damages on the actual delivery by e-commerce order, so that we could find out the test results were similar to those of the actual delivery occasions. In addition, we could perform redesign and improvement of the parcel delivery packagings for safe transportation by taking this Field-to-Lab test repeatedly. This test methods was finally proposed to be Korean industrial standard (KS), and is expected to be useful as a designing tool for the packaging optimization between protecting goods and reducing packaging waste.

• Food Science and Preservation
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• v.24 no.2
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• pp.159-167
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• 2017

This study was investigated the effects of maintaining the freshness and stabilization of supply and demand for lettuce (Lactuca sativa L.) by packaging methods in summer. Post-harvest lettuces were packaged by corrugated box, polypropylene (P) box, and individual wrapping using polyvinyl chloride (PVC) film. Then, the lettuce samples were stored at $2^{\circ}C$ and evaluated the change of quality during storage. The lettuces wrapped individually with PVC film had lower weight loss rate, color change, and browning index compared to lettuces packaged by corrugated box and P box. The SPAD value and hardness were higher in lettuces wrapped individually with PVC film than other packaging methods. The lettuces wrapped individually with PVC film were showed the highest total phenolic contents and DPPH radical scavenging activity, but there were no significantly differences by packaging methods. The lettuces packaged by corrugated box were showed the inside browning after 14 days. However, the lettuces wrapped individually with PVC film were showed the best appearance. Therefore, the packaging method of wrapped individually with PVC film were effective in maintaining the freshness during 21 days and helpful for the stabilization of supply and demand for lettuce in summer.