• Food Science and Preservation
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• v.6 no.1
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• pp.43-47
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• 1999

To develop a wrapping film, which suppresses the microbial decay through the storage and distribute of greenhouse fresh produce, the antimicrobial packaging films were made and applied to the preservation of grapes(Campbell early). For the purpose the films were made by adding 1% grapefruit seed extract(GFSE) to LDPE film(Control). Graps were separately wrapped with packaging films in the state of closely-adhered packaging as well as modified atmosphere packaging(MAP). The wrapped grapes were stored at 5$^{\circ}C$ for 65 days and then the colony count of contaminated microorganims, decay ration of grapes, the gas component within the packages and chemical qualities were investigated. The antimicrobial film packaging showed the efficient results to suppress microbial growth as compared with control. The total number of containated microorganisms were decreased gradually through all the storage period. In the closely-adhered packaging and MAP the decay ratios of grapes was 31% and 19%, indivisually. After the storage period of 65 days, the interior gas components of MAP were 4.5% of O2 and 17.6% of CO2, which were efficient for the storage of grapes. In addition, no negative effects in sweetness and acidities occurred.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2006.02a
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• pp.139-151
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• 2006

[ $\bullet$ ] 3D is proliferating in all package types $\bullet$ Thin packages challenge all assembly technologies $\bullet$ Package assembly and test are closely coupled and design for testability is imperative to success

• Journal of the Microelectronics and Packaging Society
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• v.7 no.2
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• pp.7-12
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• 2000

Copper-based leadframe sheets were oxidized in a black-oxide forming solution, and molded with epoxy molding compound (EMC) to form sandwiched double-cantilever beam (SDCB) specimens. The adhesion strength of leadframe/EMC interface was measured in terms of fracture toughness by using SDCB specimens and the fracture surfaces were analyzed by various equipments such as glancing-angle XRD, AFM, and SEM. Results showed that three types of failure paths, which were closely related to the surface condition of leadframes before molding.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.9-17
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• 2015

After its inception in 1994, the Journal of the Microelectronics and Packaging Society has continued to make significant strides in the number and quality of publications within its field. The interest in the microelectronics and packaging research has become more critical as consumer electronic products continue its increasing trend towards thinner and lighter devices that tests the boundaries of electronic devices. This study utilizes social network analysis of all published literature in the Journal for the past 22 years. Using the keywords and abstracts available within each individual article, the publications within the Journal has focused on major topics covering (1) flip chip, (2) reliability, (3) Cu, (4) IMC (intermetallic compounds), and (5) thin film. Using the social network relationship between keywords within articles, flip chip was closely associated with reliability, BGA (ball grid array), contact resistance, electromigration in many of the published research works within the Journal. From the centrality analysis, it was found that flip chip, reliability, Cu, thin film, IMC, and RF (radio frequency) to have a high degree of centrality suggesting these key areas of research have relatively high connectivity with other research topics within the Journal and is central to many of the research fields within the micro-electronics and packaging area. The cohesiveness analysis showed research clustering of five major cohesive sub-groups and was mapped to better understand the major area of research within this field. Research within the field of micro-electronics and packaging converges many disciplines of science and engineering. The continued evolution within this field requires an understanding of the rapidly changing industry environment and the consumer needs.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2006.10a
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• pp.67-73
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• 2006

A system in package (SiP) generally contains a variety of systems such as analog, digital, optical and micro-electro-mechanical systems, integrated in a system-level package connected through a substrate. However, there are many electrical and mechanical reliability issues including the reliability issue for embedded structures. A mismatch of thermal coefficients of expansion among packaging materials and devices can lead to warping or delamination in the package. In this study, the effect of material properties of underfill, such as Young's modulus and CTE, are investigated through FEM simulation. Experimental investigation on the warpage of the package is also carried out to verify the simulation results. The results show that the reliability of the system in package is closely related to the material properties of underfill. The results of this study provide a good guidance for the material selection when designing the system in package.

• Journal of the Korean Society of Food Culture
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• v.22 no.1
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• pp.83-90
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• 2007

The changes of the color, texture and volatile flavor compounds of Yu-gwa were investigated that affected by the oxidation during storage to characteristic Yu-gwa quality. Among the proximate compositions, carbohydrate was the most abundant component, and followed by lipid and moisture. Although the change of the color showed different pattern by the packaging materials during the storage period, the value of yellowness(b) increased but that of lightness(L) decreased dramatically after 3 month storage. In the textural properties reported closely related with the moisture content, hardness was fairly affected on the period of the storage rather than the type of packaging materials. The flavor compounds of Yu-gwa were analyzed to evaluate the change of distinct volatile compounds during storage. Of the twenty one separated volatile compounds, major volatiles were aldehydes, alcohols and alkenes. The results also showed that polyethylene(PE) contained less volatiles than polypropylene(PP) by the oxidation process during storage.2,4-Decadienal was gradually increased with the period of the storage, whereas octane and furan were decreased. The results provided that the change of the flavor distribution during the storage, and also the possibility of the volatiles such as hexanal, nonanal and 2,4-decadienal as the indicator for the oxidation process.

• Food Science and Preservation
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• v.9 no.2
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• pp.148-153
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• 2002

Effect of the thickness of low density polyethylene(LDPE) Film as packaging material on changes in physicochemical characteristics of mature-green mume (Prunus mume Sieb. et Zucc) fruits during storage at different temperatures(0, 10 and 25$\^{C}$) were investigated. Fruit samples stored in pouches with 30㎛ thickness of LDPE film maintained well not only external qualities such as Shape and firmness, but also internal chemical properties such as pH, acidity, the content of soluble solid and chlorophyll, and color, comparing with samples stored without packaging material or in other pouches with different film thickness(20 and 40㎛). From the results, it was found that the maintenance of quality of mature-green mume fruits during storage at 0, 10 and 25$\^{C}$ closely related to the changes in respiratory conditions for fruits affected by the film thickness of the packaging material.

• Macromolecular Research
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• v.17 no.7
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• pp.528-532
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• 2009

The size and shape of free volume (FV) holes available in membrane materials control the rate of gas diffusion and its permeability. Based on this principle, a segmented, thermo-sensitive polyurethane (TSPU) membrane with functional gate, i.e., the ability to sense and respond to external thermo-stimuli, was synthesized. This smart membrane exhibited close-open characteristics to the size of the FV hole and water vapor permeation and thus can be used as smart food packaging materials. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), positron annihilation lifetimes (PAL) and water vapor permeability (WVP) were used to evaluate how the morphological structure of TSPU and the temperature influence the FV holes size. In DSC and DMA studies, TSPU with a crystalline transition reversible phase showed an obvious phase-separated structure and a phase transition temperature at $53^{\circ}C$ (defined as the switch temperature and used as a functional gate). Moreover, the switch temperature ($T_s$) and the thermal-sensitivity of TSPU remained available after two or three thermal cyclic processes. The PAL study indicated that the FV hole size of TSPU is closely related to the $T_s$. When the temperature varied cyclically from $T_s-10{\circ}C$ to $T_s+10^{\circ}C$, the average radius (R) of the FV holes of the TSPU membrane also shifted cyclically from 0.23 to 0.467 nm, exhibiting an "open-close" feature. As a result, the WVP of the TSPU membrane also shifted cyclically from 4.30 to $8.58\;kg/m^2{\cdot}d$, which produced an "increase-decrease" response to the thermo-stimuli. This phase transition accompanying significant changes in the FV hole size and WVP can be used to develop "smart materials" with functional gates and controllable water vapor permeation, which support the possible applications of TSPU for food packaging.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.47-53
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• 2022

Recently, intelligent packaging of foods has been increasingly developed in response to the growing interest of consumers in checking food quality. Indicators, an important element in intelligent packaging, change color to detect specific substances or indicate food quality changes. Gas indicators can be built into food packaging to detect volatile substances that are released when food quality changes. Ethylene gas is produced as climacteric fruits ripen. Climacteric fruit ripening results from a rapid increase in ethylene production and respiration. In the case of packaged fruits, the ethylene gas concentration in the headspace is closely related to the ripeness of each fruit variety. If an ethylene gas indicator that can be used in fruit packaging is available, the consumer will be able to eat the fruit at the optimal time. In this paper, the characteristics and pros and cons of the ethylene gas indicators developed so far were analyzed by reviewing various types of indicators such as metal reduction-based indicator, fluorescence-based indicator, pH indicator-based indicator, and liposome-based indicator.

• Food Science and Preservation
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• v.9 no.3
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• pp.271-276
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• 2002

To develop a wrapping film, which suppresses the microbial decay through the storage and prolongs the selflife of fruits and vegetables, the antimicrobial packaging films were prepared and applied to the preservation of strtwberries and cucumbers. Low density polyethylene(LDPE) film of 50㎛ thickness was faricated with 1% of Scutellariae baicalensis extract. The LDPE film impregnated with Scutellariae baicalensis extract showed antimicrobial activity on the disk test against Bacillus cereus, Escherchia coli and Fusarium sp.. The antimicrobial film changed the color and light transmittance, but did not affect heat shrinkage, mechanical tensile strength and wattability. Strawberries and cucumbers were separately wrapped with packaging films in the state of closely-adhered packaging as well as modified atmosphere packaging(MAP). The wrapped strawberries and cucumbers were stored for 21 days at 5$\^{C}$ and for 40 days at l0$\^{C}$, respectively. For the packaged strawberries and cucumbers at 5$\^{C}$ and 10$\^{C}$, the LDPE film impregnated with Scutellariae baicalensis extract showed the reduced growth of total aerobic bacteria, molds and yeasts and did not give any negative effect on other quality attributes during storage in comparison with conttrol film without any additive.