Earticle

조피볼락 필렛 제품의 온도에 따른 CO2 용해도 측정 결 과 온도가 낮을수록 용해 정도가 증가하는 것으로 확인하 고, 온도에 따른 Henry의 상수 값을 직선방정식으로 정립 하였다. 얻어진 CO2 용해특성과 CO2 물질수지식을 활용하 여 여러 조건의 유연 포장 내 평형 형성 후 얻어지는 CO2 분압과 포장 부피를 예측할 수 있었다. 조피볼락 필렛의 신 선도 유지를 위해 MAP(변형기체포장)를 적용하여 10oC에 서 5일 동안 저장하면서 포장 내 MA 조성에 따른 품질변 화를 확인하였다. MA 조성에 따른 품질을 확인해 본 결과 호기성 총균수와 총 휘발성염기질소의 수치가 MA 기체조 성별로 유의한 차이가 있음을 확인할 수 있었다. CO2농도 가 높은 MA 조건에서는 호기성 총균수의 증식이 억제되었 으며, O2가 포함되는 MA 조건에서 휘발성염기질소 함량이 낮았다. 조피볼락 필렛에 대해 호기성균 증식을 억제하면서 휘발성염기질소 함량이 낮은 MA 조건을 선택한다면 CO2 (60):O2(30):N2(10)의 조건이 좋은 품질을 유지하는 것으로 확인되었다.

In order to extend shelf life for rockfish fillets by modified atmosphere packaging (MAP), different package atmospheres were compared in the product quality preservation. Firstly, CO2 solubility was measured at 0, 5, 10, and 15oC to be incorporated into the mathematical model to predict the volume and CO2 concentration of the package at expected storage temperature. The CO2 solubility given in Henry’s constant decreased with temperature to be fitted with a linear equation. Then air packaging as control and four MAP conditions of 100 g fillets were prepared and stored for duration of 5 days at 10oC to compare them in the quality preservation effect. Four MAP conditions employed were CO2(60):O2(30):N2(10), CO2(60):O2(0):N2(40), CO2(30):O2(30):N2(40) and CO2(30):O2(0):N2(70). MAP conditions with high CO2 concentration inhibited total aerobic bacteria, and the conditions containing O2 led to low TVB-N. MAP of CO2(60):O2(30):N2(10) was found to be the best condition for rockfish fillet preservation considering total aerobic bacteria growth and nitrogenous volatiles production.

최근 소비자들의 소비 형태가 온라인 쇼핑 및 간편식, 배 달 음식 등 비대면 소비를 위한 서비스 시장이 크게 확대 됨에 따라 플라스틱 일회용 제품의 소비가 급증하게 되면 서, 사용한 플라스틱 폐기물에 의한 여러 환경오염 문제들 이 발생하고 있다. 이러한 문제를 해결하기 위해 국제적으 로 플라스틱 사용을 줄이고, 환경친화성 및 재활용성이 높 은 지속 가능 물질로 대체하려는 움직임을 보이고 있다. 본 연구에서는 재활용성이 높은 종이에 다양한 종류의 배리어 코팅을 적용한 종이 시료의 물성과 배리어 특성 및 재활용 성 등을 평가하여 실제로 식품용으로 사용되는 종이의 코 팅층 종류와 이에 따른 물성 및 배리어성 개선 효과 및 재 활용성에 미치는 영향을 확인하고자 하였다. 배리어 코팅종류는 PE와 PP, 개질 아크릴 코팅이 된 종이 시료를 사 용하였으며, 코팅 처리하지 않은 종이를 대조군으로 하여 평가를 진행하였다. 형태학적 분석을 통해 PE의 코팅층은 약 30 μm, PP는 약 20 , 개질 아크릴은 10 μm의 코팅층 두께를 보여주었으며, 섬유조직 형태를 보여주던 대조군의 표면과 달리 배리어 코팅 종이는 코팅층으로 인하여 매끈 한 표면 형태를 보여주었다. 기계적 물성 평가에서는 PE 코팅 종이와 개질 아크릴 코팅 종이에서 대조군이 비해 인 장강도와 파열강도에서 개선되는 결과를 보여주었으며, PP 코팅 종이에서는 파열강도 외에 대조군과 유의적 차이를 보 여주지 않았다. 공기 투기도 평가로 배리어 코팅층이 없는 대조군에서 약 2.24 μm/Pa·s로 가장 높은 투기도 값을 보여 주었으며, 배리어 코팅 종이의 경우 모두 0.003 μm/Pa·s 이 하의 상대적으로 낮은 투기도 값을 보여주었다. 또한 Cobb 사이즈도 대조군에서 약 43.77 g/m2로 가장 높은 흡수 특성 을 보였으며, 배리어 코팅 종이 시료에서는 2.80 g/m2 이하 의 흡수 특성을 보여주었다. 이는 이미 내수성 및 기체 차 단 특성을 가진 고분자의 특성으로 종이의 차단 특성도 개 선된 것으로 판단된다. 내유성 평가에서도 PE 코팅 종이와 PP 코팅 종이에서 최고 측정값인 12 등급으로 내유성이 높 은 특징을 보여주었으며, 개질 아크릴 코팅 종이는 5 등급 으로 PE, PP 코팅 종이 보다 상대적으로 낮은 내유성을 보여주긴 하였으며, 대조군은 0 등급으로 내유성이 없는 모 습을 보여주었다. 코팅 처리별 종이의 재활용성 평가에서 대조군의 리젝트율은 5.25%로 모든 시료 중 미해리분이 가 장 낮은 모습을 보여주었으며, PE 코팅 종이와 PP 코팅 종이는 각각 19.04%, 16.57%로 리젝트율이 증가함을 나타냈다. 상대적으로 높은 리젝트율 값은 PE 코팅 종이와 PP 코팅 종이는 해리 시 코팅 층이 작은 크기로 조각나 미분 화되어 슬릿에 걸러지는 것으로 확인하였으며, 이는 미해리 분으로 인해 재활용에 어려움이 발생할 것으로 판단된다. 개질 아크릴 코팅 종이의 리젝트율은 6.25%로 대조군과 유 사하게 미해리분 없이 스크린을 거의 통과되는 현상을 보 여주었다. 이 결과는 개질 아크릴 수지의 수해리성이 높아 발생한 것으로 판단된다. PE 및 PP 코팅 종이에 비교하여 개질 아크릴 코팅 종이가 재활용성 평가에서 더 효율적인 결과를 가짐을 나타내며, 추가 해리되어 스크린 업셉트된 펄프 슬러리를 사용하여 제조한 재활용지에 대한 종이의 품 질 변화는 향후 보강 연구가 필요할 것으로 판단된다.

The worldwide effects of COVID-19 have led to a surge in online shopping and contactless services. The consumption pattern has caused the issues such as the environmental pollution together with the increase of plastic waste. Reducing the reliance on the petroleum based plastic use for the package and replacing it with environmentally friendly material are the simple ways in order to solve those problems. Paper is an eco-friendly product with high recyclability as the food packaging materials but has still poor barrier properties. A barrier coating on surface of the paper can be achieved with the proper packaging materials featuring water, gas and grease barrier. Polyethylene (PE) or polypropylene (PP) coatings which are generally laminated or coated to paper are widely used in food packaging applications to protect products from moisture and provide water or grease resistance. However, recycling of packaging containing PE or PP matrix is limited and costly because those films are difficult to degrade in the environment. This study investigated the recyclability of modified acrylic emulsion coating papers compared to PE and PP polymer matrixes as well as their mechanical and gas barrier properties. The results showed that PE or modified acrylic emulsion coated papers had better mechanical properties compared to the uncoated paper as a control. PE or PP coating papers showed strong oil resistance property, achieving a kit rating of 12. Those papers also had a significantly higher percentage of screen reject during the recycling process than modified acrylic coated paper which had a screen rejection rate of 6.25%. In addition an uncoated paper had similar value of a screen rejection rate. It may suggest that modified acrylic emulsion coating paper can be more easily recycled than PE or PP coating papers. The overall results of the study found that modified acrylic emulsion coating paper would be a viable alternative to suggest a possible solution to an environmental problem as well as enhancing the weak mechanical and poor gas barrier properties of the paper against moisture.

Though box compression strength (BCS) is commonly used as a performance criterion for shipping containers, estimating BCS remains a challenge. In this study, artificial neural networks (ANN) are implemented as a new tool, with a focus on building up ANN architectures for BCS estimation. An Artificial Neural Network (ANN) model can be constructed by adjusting four modeling factors: hidden neuron numbers, epochs, number of modeling cycles, and number of data points. The four factors interact with each other to influence model accuracy and can be optimized by minimizing model’s Mean Squared Error (MSE). Using both data from the literature and “synthetic” data based on the McKee equation, we find that model estimation accuracy remains limited due to the uncertainty in both the input parameters and the ANN process itself. The population size to build an ANN model has been identified based on different data sets. This study provides a methodology guide for future research exploring the applicability of ANN to address problems and answer questions in the corrugated industry.

This paper analyzes the vibration characteristics within the cargo compartment of a three-wheeled cargo bike when used on both regular roads and dedicated bicycle lanes. When cargo is loaded into the cargo compartment of a cargo bike and driven on the road, the shocks and vibrations transmitted from the ground can potentially affect the transported goods and even lead to product damage. As the vibration characteristics applied to the cargo compartment may vary depending on the condition of the road, vibration sensors were attached to the cargo bike's cargo compartment for data collection during operation on different road types. According to KS T ISO 13355 standards, the cargo bike can withstand vibrations within the range of 10 Hz to 60 Hz when operating on both bicycle lanes and regular roads. However, it is observed that there are peaks exceeding the profile in the frequency range of 3–6 Hz. In the 70-200 Hz range, the profile is exceeded on both regular roads and bicycle lanes, with a tendency for higher exceedance on bicycle lanes. The Grms value within the frequency range of KS T ISO 13355 is 5.926 m/s² (0.604 Grms). When operating on bicycle lanes with cargo, the Peak envelope optimization PSD value is 6.553 Grms, while on bicycle lanes, it is 7.708 Grms, indicating a difference of at least tenfold.

In this study, we conducted a comparative life cycle assessment (LCA) of two different products, considering reusable and single-use packaging for fresh food distribution. For reusable packaging, we utilized expanded polyethylene (EPE), while for comparison, a disposable box made of widely used expanded polystyrene (EPS) was selected. We comprehensively analyzed the environmental impacts of production, transportation, reprocessing (for reused boxes), and disposal across 18 impact categories. Upon analyzing the actual reuse of 300 rounds of fresh food, the cumulative global warming potential (GWP) values for the EPE box were found to be 280.21 kg carbon dioxide (CO2) eq, demonstrating a significant 75% reduction compared to those of the EPS box. Furthermore, it was observed that the GWP values for the EPE boxes became equivalent to those of the EPS boxes after 12 rounds of reuse. In conclusion, reusable packaging shows substantial potential to contribute to the reduction of environmental burdens, aligning well with global environmental requirements for sustainable food distribution and related industries.

Garlic (Allium sativum)is a major crop in most Asian countries, and its consumption in Asia-Pacific countries exceeds 90% of the global consumption. It contains beneficial ingredients and numerous essential nutrients, such as manganese, vitamin B6, and vitamin B1. Garlic demand is rising not only in Asian countries but also around the world. Particularly, garlic demand has been steadily increasing in European countries, such as Spain, France, Italy, and the American continent. In South Korea, 331,671 tons and 387,671 tons of garlic was produced in 2018 and 2019, respectively, making the country the fifth ranking garlic producer in the world, and the production has been increasing every year. In this study, the study on temperature distribution in cold storage of Korean garlic in folding wire mesh pallet container using CFD (Computational Fluid Dynamics) analysis was performed and Computations were based a commercial simulation software (ANSYS Workbenh Ver. 18.0). Considering the respiration heat of garlic, the decreasing rate of temperature in the area in contact with the cold air was fast due to the inflow of cold air inside, while the decreasing rate of temperature in the center of the pallet was very low. In order to maintain a uniform temperature distribution inside the agricultural product storage pallet in a low-temperature warehouse, it is considered desirable to install an air passageway to allow lowtemperature air to flow into the wire mesh pallet.

The increasing saturation challenges in storage facilities for Low- and Intermediate-Level Radioactive Waste call for a more efficient storage approach. Consequently, we have developed a square-structured container that features a storage capacity approximately 20% greater than that of conventional drum-type containers. Considering the need to contain various radioactive wastes from nuclear power usage securely until they no longer pose a threat to human health or the environment, this study focuses on evaluating the sealing efficacy of the newly designed rectangular container using finite element analysis. Since radioactive waste containers typically do not experience external forces except under special circumstances, our analysis simulated the impact of an external force, assuming a fall scenario. After fastening the bolts, we examined the vertical stress distribution on the container by applying the calculated external force. The analysis confirms the container's stable seal.

This study was conducted as a basic study for the selection of tags suitable for logistics management in the palletized unit-load unit and the development of various technologies to activate the palletized unit-load shipment of agricultural products through local APCs. Three types of passive RFID tags of UHF 900 MHz and one type of active RFID tag of 2.4 GHz band designed and manufactured through this study were used to analyze the receiving strength according to the tag’s attachment location and distance of the palletized unit-load of agricultural products. In the passive RFID tag, there was a large difference in receiving strength by the tag’s attachment location and a large amount of data loss depending on the distance within 30 m, whereas, in the active RFID tag, it was superior to the passive tags in terms of both receiving strength and data loss. Therefore, active tags are desirable from the perspective of multiple identification of warehouses with large spaces in relation to the application of RFID tags for palletized unit-loads of agricultural products, but the development of low-power technologies such as software wakeup power management as well as hardware to minimize battery power consumption is necessary.

Sustainable energy supplies without the recharging and replacement of the charge storage device have become increasingly important. Among various energy harvesters, the triboelectric nanogenerator (TENG) has attracted considerable attention due to its high instantaneous output power, broad selection of available materials, eco-friendly and inexpensive fabrication process, and various working modes customized for target applications. In this study, the amount of voltage and current generated was measured by applying the PSD profile random vibration test of the electronic vibration tester and ISTA 3A according to the time of Anodized Aluminum Oxide (AAO) pore widening of the manufactured TENG device Teflon and AAO. The discharge and charging tests of the integrated module during the random simulated transport environment and the recognition distance of RFID were measured while agricultural products (onion) were loaded into the returnable folding plastic box. As a result, it was found that AAO alumina etching processing time to maximize TENG performance was optimal at 31 min in terms of voltage and current generation, and the integrated module applied with the TENG module showed a charging effect even during the continuous use of RFID, so the voltage was kept constant without discharge. In addition, the RFID recognition distance of the integrated module was measured as a maximum of 1.4 m. Therefore, it was found that the surface condition of AAO, a TENG element, has a great influence on the power generation of the integrated module, and due to the characteristics of TENG, the power generation increases as the surface dries, so it is judged that the power generation can be increased if the surface drying treatment (ozone treatment, etc.) of AAO is applied in the future.