• 한국정보통신학회논문지
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• 제26권8호
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• pp.1231-1237
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• 2022

적재 폐기물의 적재 높이와 압력, 대표적 구성폐기물인 목재, 건전지, 플라스틱 폐기물의 건조, 표면의 탄화변화를 동적으로 인지해야 한다. 동적 상황인지 서비스는 유니버설미들웨어 기반 BCN 융합 통신 서비스인 Ambient SDK 모델을 기반으로 플랫폼을 구성하였다. 또한, 적재 폐기물에서 자연발화의 발효열 발화 분석 자료를 기반으로 화재 발생 원인을 규명하는 상황인지 시스템을 구성하였다. 유니버설미들웨어를 활용하여 화재 조기경보 유형별 시나리오 구성에 적용할 수 있는 실시간 동적 서비스 플랫폼을 구축하였다. 그리하여, 저온발화 화재 가능성 데이터 분석을 위한 IoT 상황인지 플랫폼을 동적으로 구성하여 제시하였다.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2682-2695
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• 2021

This paper aims to evaluate the structural dynamic responses and damage/failure of the nuclear fuel reprocessing plant under the free drop impact of spent fuel cask (SFC) and fuel assembly (FA) during the on-site transportation. At the present Part I of this paper, the large-scale SFC model free drop test and the corresponding numerical simulations are performed. Firstly, a composite target which is composed of the protective structure, i.e., a thin RC plate (representing the inverted U-shaped slab in the loading shaft) and/or an autoclaved aerated concrete (AAC) blocks sacrificial layer, as well as a thick RC plate (representing the bottom slab in the loading shaft) is designed and fabricated. Then, based on the large dropping tower, the free drop test of large-scale SFC model with the mass of 3 t is carried out from the height of 7 m-11 m. It indicates that the bottom slab in the loading shaft could not resist the free drop impact of SFC. The composite protective structure can effectively reduce the damage and vibrations of the bottom slab, and the inverted U-shaped slab could relieve the damage of the AAC blocks layer dramatically. Furthermore, based on the finite element (FE) program LS-DYNA, the corresponding refined numerical simulations are performed. By comparing the experimental and numerical damage and vibration accelerations of the composite structures, the present adopted numerical algorithms, constitutive models and parameters are validated, which will be applied in the further assessment of drop impact effects of full-scale SFC and FA on prototype nuclear fuel reprocessing plant in the next Part II of this paper.

• 한국식품저장유통학회지
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• 제31권1호
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• pp.80-98
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• 2024

Edible insects, such as the two-spotted cricket (Gryllus bimaculatus, GB), have high nutritional value but are not widely consumed because of their appearance and smell. Consequently, the development of foods containing these insects in less recognizable forms, e.g., flour-like powders, has drawn considerable attention. Herein, we investigated the quality characteristics of muffins prepared from wheat flower supplemented with fresh ginseng (5%) and GB (0, 10, 20, and 40%) powders. GB loading was negatively correlated with muffin volume, height, moisture content, and textural properties (hardness, springiness, cohesiveness, and chewiness) and positively correlated with crude protein content and antioxidant properties. Significant (p<0.05) color differences were observed between samples with different GB loadings. The contents of hexanal and nonanal, which are the major volatiles responsible for off-flavor, increased with increasing GB loading, and the number of volatiles maximized at 40% GB. Sensory preference decreased in the order of 0% GB>10% GB≈ 20% GB>40% GB. Based on these results, a GB loading of 20% offered the best trade-off between attractiveness and nutritional value. Thus, this study promotes the widespread use of GB in the food industry and the development of various edible-insect-based food products.

• 한국양식학회지
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• 제13권3호
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• pp.267-275
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• 2000

이 연구는 값싸고 높은 비 표면적을 제공할 수 있는 발포스티로폼 입자를 packed column 에어레이터의 산소전달 매질로 이용 가능성을 알기 위하여 매질의 깊이와 수리학적부하량에 따른 산소 전달 특성과 효율을 조사 하였다. 이용된 발포스티로폼 입자는 직경 2.5 mm의 구형이었으며, 비표면적이 1350 $m^2$/$m^3$으로 일반적으로 이용되는 매질에 비해 약 3.7~7.0배 더 넓은 비표면적을 제공할 수 있다. 이 매질을 직경 10 cm, 높이 1 m의 내부 관찰이 용이한 아크릴 관으로 제작한 packed column 에어 레이터에 0, 4.5, 9그리고 18 cm의 매질을 채워 넣고, 수온 20, 25 및 3$0^{\circ}C$에 대해 수리학적 부하량을 2, 4 및 5.6 $m^3$/$m^2$/min로 각각 달리하여 산소전달특성을 실험한 결과(Exp. 1),모든 실험 수온에서 수리학적 부하량이 증가함에 따라 표준산소전달률이 증가하였으나 매질의 깊이는 9 cm 까지는 증가하다가 18 cm에서는 감소하였다. 표준산소전달률은 매질 깊이 9 cm에서 수리학적 부하량이 5.6 $m^3$/$m^2$/min일 때 가장 높았다. 그러나 수리학적 부하량이 증가함에 따라 펌프의 소모 전력이 증가하여, 단위소모 전력당 표준에어레이션 효율은 매질의 깊이 9 cm에서 수리학적부하량 2 $m^3$/$m^2$/min일 때 가장 높았다. 따라서 모든 수리학적 부하량에서 매질의 깊이 9 cm 일 때 표준산소전달률과 표준에어레이션 효율이 가장 좋았다. 이 매질을 직경 20 cm, 높이 2 m의 PVC관으로 제작한 packed column 에어레이터에 깊이를 0, 9, 18, 27 및 36 cm로 넣고 순환여과식 시설 내에 실험실 규모의 적용실험을 통해 에어레이터의 효율을 조사하였는데 (Exp.2), 실험 수온 27$^{\circ}C$에서, Exp. 1에서와 동일한 3개의 수리학적 부하량에서 산소 전달률을 측정한 결과, Exp. 1에서와 같이 수리학적 부하량과 매질의 깊이의 증가에 따라 산소 전달률이 증가하였으며, 매질의 깊이가 가장 깊은 36 cm에 대해, 수리학적 부하량이 2 $m^3$/$m^2$/min 일때, 2 kg 02 kg $O_2$/kW-hr의 가장 높은 표준에어레이션효율을 나타내었다. 위의 두 실험 결과에 따라 packed column 에어레이터에서 발포스티로폼 입자를 산소전달 매질로 이용하여 산소 전달률을 증가시킬 수 있다는 것을 확인할 수 있었다.

• 국제물리치료학회지
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• 제10권4호
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• pp.1889-1896
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• 2019

Background: Because of the lack of accurate values for applied forces in manual therapy, manual therapists relies on the magnitude of the individual's perception during applying the force. However, excessive loading maneuvers carry risks for patients. Objective: To establish the relationship between the maximal force applied to swine skin with the specific region, sex, and baseline parameters of the subject. Design: Ex-vivo Study and laboratory Experimental research Methods: 3.5 kg of Korean pork sirloin that is a piece of swine was handled and it was set 3 dimensions; #A; #B; #C. Forty-seven participants who has no experience in physical therapy randomly carried out the experiment, indicated to push each place of the pressure spots with same posture and process under supervision from the instructor who has over 15 years of manual therapy, and we measured the pressure force in each time. Results: The biggest pressure force was recorded in spot #A, and #B was represented after #C. Pressure on #A showed certain statistic relation with height (r=.317, p<.05) and weight (r=.434, p<.01); pressure on #B showed certain relation which has statistical meaning with only height (r=.401, p<.01); pressure on #C emerged to have statistic relationship with height (r=.308, p<.05)and weight (r=.428, p<.01). The age aspect revealed relation with pressure on #A, #B and #C, but that was not statistically significant. Conclusions: It can be inferred that there is the most loss of pressure in the area where cartilage is like an island in the middle.

• 유통과학연구
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• 제11권8호
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• pp.15-23
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• 2013

Purpose - This is a case study aimed at finding a solution for improving the pallet loading efficiency in the process of delivering products through a transshipment using the T-11 and T-12 pallet systems. The study proposes a solution by demonstrating the case of a certain manufacturer A, who aims to reduce the logistics cost by using packaging sizes that are commonly applicable and can improve the compatibility between the T-11 pallet system, designated as the standard pallet in Korea, and the T-12 pallet system, which is commonly used in other foreign countries. The use of common sizes increases compatibility among the two systems and reduces both logistics and environmental costs. Thus, this case study calculates the quantitative benefits of applying common packaging sizes to improve the compatibility between the T-11 and T-12 pallet systems. These systems are considered to be the most important and widely used transportation systems in the global logistics industry. Research design, data, and methodology - This study examined manufacturer A's representative product and delivery system and assessed how manufacturer A was affected by the use of incompatible packaging sizes in the T-11 (1100 mm×1100 mm) and T-12 (1200mm×1000 mm) pallet systems, which were specified in the KS T 1002 standard. In addition, this study analyzed the impact of these packaging sizes on A's logistics cost. The TOPS program (Total Packaging System) was used to simulate pallet loading efficiency,and the main parameter studied was volume, as calculated from length, width, and height. Results - When the sizes of secondary packaging were not compatible across the T-11 and T-12 pallet systems, a reduction in loading efficiency was observed, leading to an increase in logistics cost during transshipment. Such low loading efficiencies led to a further loss of efficiency in transportation, storage and unloading. This may have a possible environmental impact with high social expenses, such as increased CO₂ emissions. Hence, this study proposed that the KS T 1002 standard be amended to include 21 packaging sizes, including 7 sizes of the 600 mm×500 mm category, which are compatible with both the T-11 and T-12 pallet systems. Conclusions - This study found that the 69 standard sizes under the T-11 pallet system and the 40 standard sizes under the T-12 system in the KS T 1002 standard can be simplified and reduced to 21 mutually compatible packaging sizes, enabling logistics standardization and reducing national-level logistics costs. If the government pays attention to this study and considers the standardization of common sizes for the T-11 and T-12 pallet systems and amends the KS T 1002 standard, this study will deliver practical value to the global logistics industry, apart from being of academic significance.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권1호
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• pp.60-71
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• 2008

The objective of this study is to evaluate the stress distribution according to the thread design and the marginal bone loss of a single unit dental implant under the axial and offset-axial loading by three dimensional finite element analysis. The implants used had the diameter of 5mm and 4mm with 13mm in length and prosthesis with a conical type which is 6mm in height and 12mm in diameter. The thread designs were triangular, square and buttress. In the three dimensional finite element model with $15\times15\times20mm$ hexahedron and 2mm cortical thickness, implants were placed with crown to root ratio 7:12, 10:9, 13:6 and 16:3. And additionally the axial force of 100N were applied into 0mm, 2mm and 4mm away from the center of the implants. The results were as follows 1. The maximum von-Mises stress in cortical bone was concentrated to cervical area of implant, and in cancellous bone, apical portion. 2. Comparing the von-Mises stresses in cortical bone of 2mm and 4mm offset loading with central axial loading, it were increased to 3 and 5 times in diameter 4mm implant, and 2 and 4 times, in diameter 5mm implant. 3. The square threads were more effective than the triangular and butress as the longer diameter, the offset loading, and the worse crown to root ratio. 4. The von-Mises stresses were relatively stable until crown to root ratio 13:6, but it was suddenly increased at 16:3. From the results of this study, minimum requirement of crown to root ratio of implant is 2:1, and in the respect of crown to root ratio, diameter and offset loading, square threads are more effective than triangular and buttress threads.

• 한국지반공학회논문집
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• 제32권12호
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• pp.79-91
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• 2016

토목섬유를 보강한 성토지지말뚝(GRPS) 공법은 연약지반 상부에 건설되는 성토구조물의 잔류침하를 억제하고, 공사기간을 단축할 수 있는 방법으로 그 적용성이 확대되고 있다. 이에, 세계 각국에서는 다양한 연구를 통해 설계방법을 제안해왔지만, 동적하중을 고려한 시스템의 거동은 확실하게 규명되지 않은 실정이다. 본 논문에서는 섬유보강 지지말뚝 성토체내의 동적하중 전이 특성을 분석하기 위하여 실물크기의 시스템을 조성한 후, 반복재하 실험을 수행하였다. 실험은 토목섬유를 설치하지 않은 무보강, 토목섬유를 1겹 설치한 보강, 2겹 설치한 보강을 조건으로 총 3가지 경우로 나누어 진행하였다. 말뚝과 토목섬유 상부에 각각 하중계를 설치하여 반복재하 횟수에 따른 수직하중을 측정한 결과, 토목섬유의 보강효과를 제외하고 아칭효과에 의해서만 전이되는 반복하중은 오히려 인장력이 큰 토목섬유로 보강할수록 감소하는 경향이 나타났다. 그러나 최종 말뚝으로 전달되는 반복하중의 크기는 토목섬유를 보강하지 않은 경우와 1겹, 2겹 보강한 경우에서 모두 비슷한 것으로 평가되었다. 이는 토목섬유의 보강이 말뚝으로 집중되는 하중을 증가시킨다는 기존의 연구와는 상반된 결과로, 이를 바탕으로 반복하중 전이 메커니즘의 상관관계를 분석하고자한다 또한, 반복하중 재하 초기 말뚝으로의 하중전달 효과가 감소하는 경향이 보였으며, 이는 반복하중에 의한 아칭효과 감소에서 기인한 것으로 판단된다.

• 한국인터넷방송통신학회논문지
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• 제21권3호
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• pp.115-121
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• 2021

인간의 착지 전략은 다양한 조건에서 하지역학을 통해 설명해 왔다. 그러나 중량과 착지 높이의 두 조건이 결합되었을 때 하지역학이 어떻게 반응하는지 아직 이해할 수 없다. 이 연구의 목적을 달성하기 위해 성인 남녀 총 20명은 다양한 착지 높이 0.3 m, 0.4 m, 0.5 m에서 중량(무중량, 체중의 10%, 20% 그리고 30%)을 적용해 드롭랜딩을 실시하였다. 연구결과 중량의 주효과는 모든 변인에서 통계적으로 유의하지 않았다. 반면 착지 높이의 증가에 따라 무릎관절 각도는 더 굴곡된 형태를 보였으며 통계적으로 유의하였다. 또한 착지 높이 증가에 따라 좌우, 전후, 수직지면반력, 부하율은 더 증가되는 반면, 안정화시간은 보다 짧은 시간에 생성되었으며, 통계적으로 유의하였다. 따라서 인간은 다양한 높이에서 중량을 변경시키더라도 착지 동작을 성공적으로 수행할 수 있다. 그러나 중량 조건보다 착지 높이의 변화에 더 민감하게 반응하였다. 착지 높이는 시각정보를 통해 인지 및 충격 흡수에 대비할 수 있지만, 중량 수준은 신체가 인지하기 어렵고 충격흡수를 위한 착지 전략 메커니즘에 더 적용시키기 어려운 이유를 설명해준다.

• 한국기계연구소 소보
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• 통권14호
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• pp.157-168
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• 1985

In cargo vessels, hatch covers are used to prevent sea water from penetrating into the cargo hold and to keep the vessels buoyant. And also they can be used as cargo loading devices as in container ships. In this paper, hatch covers are classified according to their operation method and their characteristics are briefly demonstrated. Systematic description on the scantling of the hatch cover panel and how to determine the capacity of the hydraulic power system fir folding hatch cover panels are also presented. The hydraulic power system is selected from the result of dynamic analysis of the movements of the hatch cover panels when stored on the upper deck. The hatch coaming height is determined as shortly as the hydraulic cylinders can be installed. This study deals with the hatch cover system of the medium sized multi-purpose cargo vessel, but the results of this study can be applied to large-sized cargo vessels with a slight change of the input data in the calculations. Further research on the high pressure pump, hydraulic cleating system and hydraulic piping will realize domestic production of the whole hatch cover system which have been supplied from foreign makers until now