가상 현실은 몰입감과 존재감을 극대화시킬 수 있다는 장점이 있어 비디오 게임, 교육, 치료 목적을 가진 다양한 콘텐츠에 널리 활용되고 있다. 또한 GearVR, DayDream, Occulus Quest 2 등의 HMD 등이 개발됨에 따라 가상 현실은 널리 보급되었다. 그러나 이러한 장비들을 사용하면 사용자가 실제 물리적인 세계를 볼 수 없다는 단점이 있어 실제 물체와 충돌하거나 넘어지는 위험한 상황에 빠질 수 있다. 만약 사용자가 시스 루 HMD를 사용하면 실제 물리적인 세계를 볼 수 있으므로 물체를 피할 수 있고 이러한 위험을 피할 수 있 는데 이러한 시스루 HMD는 광학 기반 방식이나 비디오 기반 방식으로 분류된다. 이러한 광학 기반 HMD는 렌즈를 통과하는 물리적 물체들을 볼 수 있지만 비용 문제가 있으며 비디오 기반 HMD는 비용과 카메라의 원본 이미지에 다양한 가상 효과를 추가할 수 있다는 장점이 있다. 본 논문은 이러한 장점들을 활용하여 저 렴한 비용으로 게임에 활용될 수 있도록 개발된 시스루 HMD를 설명하였으며 해당 HMD를 활용하는 게임 을 설명하였다. 본 논문을 통하여 개발된 비디오 시스루 HMD를 통해 더 많은 사용자가 저렴한 비용으로 혼합 현실 기반 게임을 즐길 수 있을 것으로 예상된다.
The physical and chemical properties of corrugated cardboard-based media were evaluated to assess their suitability as substrates for plants. Samples were collected periodically from the same study area over 5 months to determine any seasonal variabilities. In addition to the corrugated cardboard-based media, the rural soil of the study area was used as the control. The corrugated cardboard-based media showed adequate levels of moisture content and bulk density and correspondingly high porosity values when compared with the rural soil. All corrugated cardboard-based media showed adequate levels of electrical conductivity, organic matter, and correspondingly high cation exchange capacity values when compared with the rural soil in all seasons. The C/N ratio of the corrugated cardboard-based media was similar to the optimal values of 15-20. However, the pH values of the corrugated cardboard-based media were lower than the optimum value(pH 4) for plant growth and rural soil. The moisture content value which cycle bobs up and down according to sampling date, and this means that the moisture content is affected by seasonal changes in the components entering the study area. The corrugated cardboard-based media appear to be acceptable for growing plants(Lotus corniculatus var. japonicus). Finally, the use of this media permits better vegetation establishment than the use of rural soil. Our results prove that corrugated cardboard-based media can exhibit higher plant cover over a long period(September-November) as opposed to rural soil. Our study demonstrates the effectiveness of corrugated cardboard-based media for plant growth, and we recommend that future studies should focus on potential materials relevant to revegetation and management.
The usage of corrugated cardboard for packing material is increasing in these days because it is light and easy to manufacture packing boxes. However, the structure analysis of packing boxes, made of cardboard, is not well carried. The reason can be deduced that its mechanical properties for structure analysis are not well known. The cardboards are made different shapes with various types of raw materials that are paper-based compound. In addition, the cardboards are considered to be orthotropic material. This research finds mechanical properties of triple layered cardboard which is composed of outer liner and inner liner. The moduli of elasticity and of shear for liners are found from tension test and T-Peel test. The mechanical properties of the cardboard are calculated using the super position method and equivalent evaluation method.
플라스틱 Pallet와 함께 많이 사용되고 있는 골판지는 다른 포장 재료에 비해 무게가 가벼워 물류비 절감 효과를 가져 온다. 수출품의 형태와 조건에 맞는 다양한 강도와 형태 제작이 가능해 성형성이 좋고, 외부 충격에 대한 손상을 방지 할 수 있다. 그러나 기존에 골판지의 물성치가 알려지지 않아 구조해석이 어려워 구조적인 설계가 어려웠다.
골판지를 이용한 구조물 설계는 경험과 노하우에만 의존하여 포장 용기를 제작하여 정밀한 계산을 할 수 없었다.
본 논문의 연구목적은 골판지를 소재로 한 구조물 설계에서 정확도를 높이고자 설계해석 프로그램을 이용하여 응력해석을 하는데 있다. 골판지 소재로 물품의 받침대로 이용되어 상품을 적재할 때 사용되는 Pallet을 설계하고 구조를 해석 프로그램을 통해 좀 더 안전하고 신뢰성 있게 제작할 수 있도록 골판지의 물성치 값을 적용하여 응력해석을 수행한다.
제품 수출시 사용되는 포장 용기와 팔레트에는 대표적으로 나무와 플라스틱, 골판지가 있다. 나무장사는 폐기비용과 중량으로 인한 물류비용이 많이 든다. 그에 반해 골판지는 가볍고 저렴한 가격과 우수한 압축도를 가지고 있으며, 성형성이 좋고 재활용이 가능하여 활용도와 선호도가 높아지고 있다.
그러나 골판지는 비균질하며 X, Y, Z 평면으로 물성치들이 대칭성을 갖는 직교이방성 재료이므로 기존에 알려진 물성치를 얻기 어렵다.
본 연구는 골판지 팔레트 설계를 위한 구조해석을 할 수 있도록 필요한 골판지의 등가 물성치를 구하는데 목적이 있다.
골판지의 X, Y, Z 축 방향으로 탄성계수를 구하기 위해 인장 시험과 T-Peel test를 이용하여 판지의 outer liner와 inner liner의 계수를 구하고 superposition method를 이용하여 등가물성치를 구한다. 본 연구의 결과는 골판지를 이용한 설계에서 구조해석에 사용되어 설계의 정밀도를 높일 수 있다.
The purpose of this study analyzed the overview of corrugated cardboasrd manufacturing industry and then provide direction for improvement. The BREF (BAT reference document) is an important reference for licensees and officer, including the best available techniques for the industry and achievable environmental performance, technical characteristics, and economic information. In the corrugated cardboard manufacturing process, wastewater pollutants are generated throughout the production process, and water is used in the dissociation and aging process. Atmospheric emissions are mostly generated by steam production from boilers and incinerators for the dry process. SO2, NOx, CO2, CO, HCl, dust, VOC, and odor were common. In the EU-BREF (European union BAT reference documents) BAT for wastewater have taken up a relatively large proportion. Items of water pollutants in wastewater were common in COD, BOD, N, P, SS, and however EU-BREF had different pollutants such as AOX and salt compared to K-BREF. In order to improve the quality of the K-BREF, it is necessary to devise basic data research method and data acqusitiom method. Consideration should be given to additional environmental management techniques that reflect the emissions characteristics of the corrugated cardboard manufacturing process. In addition, further research is needed to develop methodologies for selecting BATs considering environmental and economic feasibility.
It is possible to use pallet for forwarding as chinese cabbages and radishes are general large-scale trading items at the agricultural wholesale market though, however, most of these are forwarded as it have packed in net bags or in P·E bags. Thus, it is still hard for palletizing. The type of packing the product in the net bag makes it difficult for palletizing. It is not a stable shape enough and easily collapsed for pallet loading. Because of this collapsibility, the corrugated cardboard box is being used to enhance forwarding efficiency, but the existing corrugated cardboard box could be crushed easily by moist what is from the agricultural product’s property and it also could be squashed by the mass of the loaded box layers on itself. In contrary, the functional waterproof corrugated cardboard box is not collapsed through palletizing and it is efficient for product management with it’s ventilation function in respond to pre-cooling effect. Furthermore, because it has various functional shapes as the open type, the partition type and so on, it is effective for maintaining freshness of the product and standardizing the distribution of agricultural product. It is well-known that it is possible to introduce this box to cargo-works of agricultural product. Consequently, the recognition of main distributors about the pallet distribution of the chinese cabbage and the radish was apprehended in this study for activating mechanization of loading and unloading. The survey was conducted to the main distributors such as the forwarder, the auction dealer and the commission merchant with Garak-dong wholesale market as the center. The appropriate packing materials and problems of the existing method for loading and unloading were derived through the survey. Especially, it was focused on analyzing the difference of recognition between the subject groups for the way of using waterproof cardboard corrugated box to deal with the difficult product for packing in normal corrugated box because of the box’s absorption of moist from the agricultural product like a chinese cabbage and a radish. Total In the cases of the forwarders and the commission merchants, the net was highly responded as 45%, 74% from each groups for the best packing material for mechanization of distribution and the waterproof corrugated cardboard box was responded as 20%, 22% from each groups as much preferable than multi-stage wooden box. However, for the radish, the waterproof corrugated cardboard box was the best material as 56%, and the auction trader group supported it for 80%. So, the using the waterproof corrugated cardboard box for mechanization of distribution was negative for the chinese cabbage, but it was positive for the radish. The average was 2.42, the standard deviation was 1.24. The negative response(about 55%) was prevailing more than positive response( about 23%). It could be analyzed that even there was the positive recognition for using the waterproof corrugated cardboard box for the radish though the preference for low price of net bag in the chinese cabbage forwarding procedure. Still now, it seems that is a burden for using the waterproof corrugated cardboard box with high price. In the analysis on the recognition differences about using the waterproof corrugated cardboard box for the chinese cabbages and the radish between the forwarders and the commission merchants, generally the negative recognition was prevailing, but the forwarders( 2.696) were more positive for using the waterproof corrugated cardboard box than the commission merchants(2.145).