• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.157-163
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• 2022

The demands for Home Meal Replacement (HMR) products are continuously increasing owing to the convenience of instant food and online food delivery. Ready-to-heat (RTH) products have received massive attention in the HMR industry because these products can be easily warmed using a microwave oven. However, the conventional microwave packaging should be opened before microwave heating to prevent bursting or food loss owing to the steam-pressure build-up inside the package. Open packaging might lead to non-uniform food heating and cross-contamination. Therefore, packaging materials that are able to release steam without opening are of interest to the HMR industry. In this study, polylactic acid(PLA)/polyethylene glycol(PEG)/nanoclay composite films were manufactured using an extrusion method as packaging materials with a smart steam-releasing function. The introduction of PEG to the PLA imparted a steam self-releasing feature to the composite films owing to the morphology change of composite films during microwave heating. Further, PEG increased the ductility of PLA, which in turn prevented bursting caused due to the steam-pressure build-up. The uniform dispersion of nanoclay obtained by a twin-screw extrusion led to stronger mechanical properties. Therefore, the smart composite films developed here can be applied as microwave packaging materials with a self-releasing function.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.1
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• pp.55-62
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• 2023

In this study, Sn-3.0Ag-0.5Cu (wt.%, SAC305) solder dipping process was performed between Ni-foam skeleton with different pore per inch (PPI) to fabricate Ni-foam/SAC305 composite solder, and then applied to the transient liquid phase (TLP) bonding process to evaluate the microstructure and mechanical properties of the bonded joint. The Ni-foam/SAC305 composite solder preform consisted of Ni-foam and SAC305, and an intermetallic compound (IMC) having a (Ni,Cu)₃Sn₄ composition was formed at the Ni-foam interface. During TLP bonding process, the IMC at the Ni-foam interface was converted to (Ni,Cu)₃Sn₄+Au, and as the bonding time increased, the Ni-foam and SAC305 continuously reacted, and the bonded joint was converted into an IMC. And it was confirmed that the 130 PPI Ni-foam/SAC305 composite solder joint was converted into an IMC at the fastest rate. As a result of performing a shear test to confirm the effect of Ni-foam on mechanical properties, solder joints under all conditions exhibited excellent mechanical properties of 50 MPa or more in the early stages of the TLP bonding process, and the shear strength tends to increase as the bonding time increases.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1079-1085
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• 2003

Modified atmosphere packaging was applied to oyster mushrooms (Pleurotus ostreatus) to study the effect of storage temperatures and packaging materialso. Whole mushrooms (200g) were package with polyethylene film $(PE,\;60{\mu}m\;thickness)$, ethylene vinyl acetate (EVA), or ceramic film (containing 5% zeolite) and stored at 0, 5, 10 and $20^{\circ}C$. Weight loss, color, firmness, gas composition $(O_2,\;CO_2)$ inside the film package and ethanol content in the tissue of MA packaged mushrooms were examined. Mushroom that were packed unwrapped in a conventional hardboard box (2 kg) lost marketability at a very early stage of storage due to weight loss, shrinkage, browning, and spore formation. During storage, film packaging prevented or retarded the deterioration of the mushrooms in the aspects of appearance, texture, and discoloration. Firmness slightly decreased with storage time. Total color difference was much higher in the control than in the film-packaged mushroom and rapidly increased at the early of storage. Correlation analysis showed a high correlation between total color difference and b values. These results were characterized by the reduced respiration rate resulting from elevated carbon dioxide and reduced oxygen levels in the package. At all storage temperatures, ethanol content in the tissue increased slightly at the early part of storage and rose considerably towards the end of the storage period. Ethanol content in the oyster mushrooms was higher in the stipe than in pileus tissues. The shelf life of the oyster mushrooms was about $8{\sim}11$ days at $0^{\circ}C$, about $4{\sim}6$ day at $5^{\circ}C$, about $2{\sim}3$ days at $10^{\circ}C$, and about $1{\sim}2$ days at $20^{\circ}C$.

• Journal of the Korean Society of Food Culture
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• v.20 no.5
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• pp.574-583
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• 2005

To investigate the importance and practice of well-being related dietary life pattern such as purchasing food materials, food habits and eating out, a survey was conducted by questionnaire and 5-point Likert score in Seoul and Gyeonggi-Do, September, 2004 and April, 2005. The responses of 732 housewives who were over 40 years were analyzed by SPSS package program. The results were as follows. Most of them were 40-49 years(74.4%), graduated highschool (66.6%) and their family type was nuclear family type(81.4%). Almost half of them had full-time job (37.1%) and part time job (15.4%). The average importance score of 'food habits', 'purchasing food materials' and 'eating out' were $4.15{\pm}0.91,\;4.06{\pm}0.96\;and\;3.25{\pm}1.01$ respectively. But the average practice score of 'food habits' was greater($3.58{\pm}1.06$) than 'purchasing food materials ($3.19{\pm}1.19$)' and 'eating out($2.54{\pm}1.05$)'. Among 5 types of 'food habits', the type of 'cut down on eating fast food' had the greatest score of importances ($4.31{\pm}0.97$) but the difference between importance and practice was greatest(0.94). Also 'consume home-made food rather than processed or ready to food' showed great scores in importance ($4.28{\pm}0.87$) and practice($3.87{\pm}1.04$). 'Consume fruits and vegetables rather than meats' and 'avoid heavy use of oils' had the importance score of $4.04{\sim}4.19$. But the practice score of 'avoid heavy use of oils' was the lowest($3.39{\pm}0.97$). Among four types of purchasing of food materials, 'purchase domestic agricultural food' was greatest($4.37{\pm}0.78$) and 'don't purchase genetically modified food' 'purchase organic food' and 'purchase whole grain products' were also great ($3.92{\sim}3.99$). But the practice score of 'purchase organic/low chemical foods($2.77{\pm}0.98$)' and 'don't purchase genetically modified food($2.99{\pm}1.41$)' were lowest. 'Go to well being restaurant' in three types of 'eating out' showed greatest in importance($3.35{\pm}0.96$) but the practice score($2.47{\pm}0.10$) was lower than the importance score. Also 'choose menu with comparing calories' had the lower score in practice($2.45{\pm}1.06$) rather than importance score($3.22{\pm}1.03$). In regarding to 'food habits', the importance score were significantly affected by type of food expense (p<0.05) and health status (p<0.05). The importance score of 'purchase food materials' were significantly affected by the type of food expense (p<0.001), type of residence(p<0.05), and self assessment of weight(p<0.05). Monthly income, especially more 400 million won, was the commonly significant effector in practice score of 'purchase food materials' and 'eating out'.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5627-5632
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• 2012

Background: The aim of the study was to determine the prevalence of shisha smoking and associated factors among medical students in Malaysia. Materials and Methods: A cross-sectional study was conducted at the Management and Science University from December 2011 until March 2012. The questionnaire consisted of five sections including socio-demographic, social environment, knowledge about shisha, psychosocial factors, and personal shisha smoking behavior. Obtained data were analyzed using Statistical Package for the Social Sciences (SPSS 13). T-test was used to determine the relationships between shisha smoking and socio-demographic characteristic. Results: A total number of 300 medical students participated in this study. Mean age was $22.5{\pm}2.5$ years. The majority were female, Malay, single, from urban areas (67%, 54%, 97%, 73%; respectively). The prevalence of shisha smoking among medical students was found to be 20%. The study revealed that many students believed that shisha does not contains nicotine, carbon monoxide, does not lead to lung cancer, dental problems and does not lead to cardiovascular diseases (25%, 20.7%, 22.3%, 29%, 26.7%; respectively). Age and sex were found to be significantly associated with smoking shisha status among medical students (p=0.029, p<0.001; respectively). Furthermore, having parents, siblings and friends smokers of shisha were found to be significantly associated with shisha smoking status (p<0.001, p<0.001, p<0.001; respectively). Furthermore, family problems, problems with friends, financial problems and university life were found to significantly associated with shisha smoking status among medical students (p<0.001, p=0.002, p<0.001, p=0.002; respectively). Conclusions: There is a high prevalence of shisha smoking and a poor knowledge about its impact on health among medical students. More attention is needed to focus on medical education in this regard. The policies that are currently employed in order to reduce the cigarettes smoking should be applied to shisha smoking and shisha products.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8345-8349
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• 2014

Background: Cancer is an increasing cause of mortality and morbidity worldwide. Incidences of common cancers has been growing in different provinces of Iran in recent years but trends in Khuzestan which shares a border with Iraq and is located in south west of Iran have not been investigated. This study aimed to assess secular changes in incidences of common cancers in Khuzestan province from 2004 to 2008. Materials and Methods: Data were collected from Khuzestan cancer registry which is a branch of Iranian Ministry of Health Cancer Registry (http://ircancer.ir) for the period 2004-2008. Data were presented as incidence rates by site, sex, age, using the crude rate and age-standardized rate (ASR) per $10^5$ persons. A direct method of standardization was applied according to the WHO guideline and data analysis was performed using the SPSS package. Results: During the 2004-2008 period, 14,893 new cases of cancer were registered in Khuzestan cancer registry. The age-standardized incidence rate of all cancers was 153.7 per $10^5$ in males and 156.4 per $10^5$ in females. The incidence was increased over the period of five years. The most incident cancers among males were skin cancer ($ASR=18.7/10^5$), stomach cancer ($ASR13.8/10^5$), lung cancer ($ASR12.9/10^5$), leukemia ($ASR=12.6/10^5$) and prostate cancer ($ASR=12.4/10^5$). In females, the most incident cancers were breast cancer ($ASR=41/10^5$), skin cancer ($ASR=16.4/10^5$), colorectal cancer ($ASR=10.0/10^5$), leukemia ($ASR=8.1/10^5$) and lung cancer ($ASR=6.9/10^5$). Conclusions: Incidences of various cancers are rising in Khuzestan. It is necessary to develop and implement comprehensive cancer control programs in this region which could be monitored and evaluated by the future trend data from Khuzestan cancer registry.

• Imaging Science in Dentistry
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• v.47 no.2
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• pp.75-86
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• 2017

Purpose: The purpose of this study was to apply a newly developed free software program, at low cost and with minimal time, to evaluate the quality of dental and maxillofacial cone-beam computed tomography (CBCT) images. Materials and Methods: A polymethyl methacrylate (PMMA) phantom, CQP-IFBA, was scanned in 3 CBCT units with 7 protocols. A macro program was developed, using the free software ImageJ, to automatically evaluate the image quality parameters. The image quality evaluation was based on 8 parameters: uniformity, the signal-to-noise ratio (SNR), noise, the contrast-to-noise ratio (CNR), spatial resolution, the artifact index, geometric accuracy, and low-contrast resolution. Results: The image uniformity and noise depended on the protocol that was applied. Regarding the CNR, high-density structures were more sensitive to the effect of scanning parameters. There were no significant differences between SNR and CNR in centered and peripheral objects. The geometric accuracy assessment showed that all the distance measurements were lower than the real values. Low-contrast resolution was influenced by the scanning parameters, and the 1-mm rod present in the phantom was not depicted in any of the 3 CBCT units. Smaller voxel sizes presented higher spatial resolution. There were no significant differences among the protocols regarding artifact presence. Conclusion: This software package provided a fast, low-cost, and feasible method for the evaluation of image quality parameters in CBCT.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.1
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• pp.41-45
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• 2018

As the size of semiconductor chip shrinks, the electronic industry has been paying close attention to fan-out wafer level packaging (FO-WLP) as an emerging solution to accommodate high input and output density. FO-WLP also has several advantages, such as thin thickness and good thermal resistance, compared to conventional packaging technologies. However, one major challenge in current FO-WLP manufacturing process is to control wafer warpage, caused by the difference of coefficient of thermal expansion and Young's modulus among the materials. Wafer warpage induces misalignment of chips and interconnects, which eventually reduces product quality and reliability in high volume manufacturing. In order to control wafer warpage, it is necessary to understand the effect of material properties and design parameters, such as chip size, chip to mold ratio, and carrier thickness, during packaging processes. This paper focuses on the effects of thickness of chip and molding compound on 12" wafer warpage after PMC of EMC using finite element analysis. As a result, the largest warpage was observed at specific thickness ratio of chip and EMC.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.2013-2018
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• 2015

Background: The aim of the study was to assess the extent of knowledge, attitudes and practical behavior of women in Bojnourd conerning the Pap smear test. Materials and Methods: This cross-sectional and population-based study was conducted with 1000 Iranian women aged 15-60 years old in Bojnourd city. In order to collect the data, a validated questionnaire was provided in four sections covering demographic information and questions about knowledge, attitude and practice about the Pap smear. Statistical analysis was performed with the Statistical Package for Social Sciences (version 17.0) applying a 0.05 significance level. Results: Evaluation of knowledge showed that 146 women (14.6%) had very weak, and 594 women (59.4%) had weak knowledge. In contrast, most of the women studied, 873 (87.3%), had a positive attitude toward the Pap smear test. According to the findings, 375 women (37.6%) had done this test so far. Findings indicated that the extent of knowledge had a meaningful relationship with the attitude status (p<0.0001). Also, there was a meaningful relationship between knowledge and practice, so that the weakest practice was seen in women who had weak knowledge (61.1%), (p<0.0001). Conclusions: According to findings of this research, most women do not have an appropriate knowledge about the necessity of having the Pap smear test, so that only a low percentage of women had undergone this test.

• Journal of the Korean Ceramic Society
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• v.52 no.4
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• pp.229-233
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• 2015

Currently, the majority of commercial white LEDs are phosphor converted LEDs made of a blue-emitting chip and YAG yellow phosphor dispersed in organic silicone. However, silicone in high-power devices results in long-term performance problems such as reacting with water, color transition, and shrinkage by heat. Additionally, yellow phosphor is not applicable to warm white LEDs that require a low CCT and high CRI. To solve these problems, mixing of green phosphor, red phosphor and glass, which are stable in high temperatures, is common a production method for high-power warm white LEDs. In this study, we fabricated conversion lenses with LUAG green phosphor, SCASN red phosphor and low-softening point glass for high-power warm white LEDs. Conversion lenses can be well controlled through the phosphor content and heat treatment temperature. Therefore, when the green phosphor content was increased, the CRI and luminance efficiency gradually intensified. Moreover, using high heat treatment temperatures, the fabricated conversion lenses had a high CRI and low luminance efficiency. Thus, the fabricated conversion lenses with green and red phosphor below 90 wt% and 10 wt% with a sintering temperature of $500^{\circ}C$ had the best optical properties. The measured values for the CCT, CRI and luminance efficiency were 3200 K, 80, and 85 lm/w.