• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.59-59
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• 2020

수국 '베레나 그린'의 줄기하단의 엽을 제거하고 5엽 상태에서 수돗물과 0.1% 크리잘 RVB에 각각 담가 4℃에서 24시간 물올림을 하고 물올림을 하고, 줄기를 60~70cm 길이로 끝을 대각선으로 절단하여 물올림용액을 채운 물 대롱을 끼운 다음 꽃을 보호하기 위한 비닐 슬리브를 씌워 유통용 종이상자에 담아 5±1℃ 냉장차로 국립원예특작과학원으로 운반하였으며, 절화수명 및 관련 특성분석을 위해 평가실로 옮기기 전까지 유통용 종이상자에 담긴 상태로 저온저장고(5±1℃)에 보관하였다. 보존용액에 따른 절화특성 조사를 위해 절화를 평가실에 전시하기 전에 절화의 줄기길이를 40cm로 맞춰 절단한 뒤에 보존용액을 800 mL 채운 플라스틱 화병에 꽃아 절화 화관끼리 서로 닿지 않도록 배치하였으며 22±2℃ 실내에서 절화수명을 조사하였다. 보존용액으로 4% 차아염소산나트륨 용액, 1% sucrose + 250 mg/L 8-hydroxquinoline + 100 mg/L citric acid로 이루어진 용액(HQ) 그리고 시중에서 수국 절화 보존제로 판매되는 크리잘 프로 II, III와 크리잘 clear 0.5% 용액을 사용하였다. 수돗물에 물올림하였을 때 보존용액인 0.5% 크리잘 프로 II에서는 33.8일, 0.5% 크리잘 프로 III에서는 27.7~33.5일, 크리잘 클리어는 33.7일, 차아염소산나트륨과 수돗물은 각각 26.2, 28.8일이었고, HQ 용액은 49.0일로 크리잘보다 15일, 수돗물보다 20일 절화수명이 연장되었다. 수국 '베레나 그린'의 보존용액으로 1% sucrose + 250 mg/L 8-hydroxquinoline + 100 mg/L citric acid를 사용하는 것이 관상기간을 연장하는 데 효과적이었다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.509-523
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• 2023

The high-level nuclear waste (HLW) repository is exposed to complex environmental conditions consisting of high temperature, high humidity, and radiation, resulting in structural deterioration. Therefore, structural health monitoring is essential, and piezo sensors are used to detect cracks and estimate strength. However, since the monitoring sensors installed in the disposal tunnel and disposal container cannot be replaced or removed, the quantitative life of the monitoring sensor and its suitability must be assessed. In this study, the life of a piezo sensor for monitoring was assessed using an accelerated life test (ALT). The failure mode and mechanism of the piezo sensor under high temperature conditions were determined, and temperature stress's influence on the piezo sensor's life was analyzed. ALT was conducted on temperature stress and the relationship between temperature stress and piezo sensor life was suggested. The life of the piezo sensor was assessed using the Weibull probability distribution and the Arrhenius acceleration model. The suggested relationship can be used in multiple stress ALT designs for more precise life assessment.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.148-153
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• 2017

During natural ageing of HTPB propellant undergoes a series of slow physico-chemical degradation reactions. By using accelerated ageing conditions it is possible to simulate the material behaviour at different time-temperature conditions especially focused on the in-service conditions. Ageing behaviour of HTPB propellant were investigated using HFC(Micro-Heat Flow Calorimeter) is universal technique for measuring the rate of slow chemical and physical processes in long-term storage.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.5
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• pp.59-65
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• 2018

During natural aging, hydroxyl-terminated polybutadiene(HTPB) propellant undergoes a series of slow physico-chemical degradation reactions. By using accelerated ageing conditions it is possible to simulate the material behavior at different time-temperatures focusing on in-service conditions. Aging behaviors of HTPB propellant are investigated using HFC(heat flow calorimeter), a universal technique for measuring the rate of slow chemical and physical processes in long-term storage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.64-72
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• 2020

DELAY M9 is an ammunition used in combination with the fuse M904 and M905 of aviation drop-off ammunitions. Due to the properties of the ammunition, the performance or safety of the ammunition cannot be verified until it is used, because of its one-time function, no reproduction and is finally destroyed at the same time. Long-term storage of ammunition in use by the army is inevitable due to its operational characteristics, and a test evaluation is required to maintain and verify the performance of stored ammunition for immediate use in case of emergency. This paper estimates the reliability and shelf life of the DELAY M9 ammunition by using the test data obtained through ASRP performed from the past to the present. The result of the performance evaluation test for the currently stored DELAY M9 ammunition is analyzed, and the reliability and shelf-life of the stored ammunition are assessed by examining the number of defects according to the storage time and production year. This research result can be used to manage the stored ammunition, such as ASRP planning and evaluation test, result analysis and munition state decision.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.2
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• pp.215-223
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• 2012

A violet smoke hand grenade(KM18) is used to generate signals. The grenade is considered to fail when its smoke emission time is longer than the specified one so that its smoke concentration becomes lighter. Accelerated degradation test for the grenade was performed, and then failure in smoke emission time was reproduced from the test. Stress for the degradation test was selected as temperature/humidity from the pre-test results. Degraded data of emission time from the accelerated test were analyzed through applying a distibution-based degradation model. Then, Peck Model was applied to predict the storage life under field conditions. In addition, the predicted storage life was compared with that of ASRP(Ammunition Stockpile Reliability Program).

• The KIPS Transactions:PartC
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• v.15C no.1
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• pp.19-30
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• 2008

Sensor nodes are used as a storage space in the data centric storage method for sensor networks. Sensor nodes save the data to the node which is computed by hash table and users also access to the node to get the data by using hash table. One of the problems which the data centric storage method has is that queries from many users who are interested in the popular data could be concentrated to one node. In this case, responses for queries could be delayed and the energy of heavy loaded node could be dissipated fast. This would lead to reduction of network life time. In this paper, ALT, Data Centric Storage based on Adaptive Local Trajectory, is proposed as scalable data centric storage method for sensor network. ALT constructs trajectory around the storage node. The scope of trajectory is increased or decreased based on the query frequency. ALT distributes the query processing loads to several nodes so that delay of response is reduced and energy dissipation is also distributed.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.207-214
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• 2017

There is little information about the seed longevity of wild plants, although seed bank storage is an important tool for biodiversity conservation. This study was conducted to predict the seed viability equation of Agastache rugosa. The A. rugosa seeds were stored at moisture contents ranging from 2.7 to 12.5%, and temperatures between 10 and $50^{\circ}C$. Viability data were fitted to the seed viability equation in a one step and two step approach. The A. rugosa seeds showed orthodox seed storage behaviour. The viability constants were $K_E=6.9297$, $C_W=4.2551$ $C_H=0.0329$, and $C_Q=0.00048$. The P85 of A. rugosa seeds was predicted to 152 years under standard seed bank conditions. The P85 predicted by seed viability equation can be used as basic information for optimization of seed storage processes.

• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.193-198
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• 2012

The following results are from the test of semi-gel electrolyte to store energy efficiently and use advanced VRLA batteries by photovoltaic and wind power generation. Semi-Gel electrolyte with Silica 5% became Gel after 1 and half hour. It shows it is the most suitable time that the electrolyte can be absorbed into the separator and active material of plate to be gel. The test also says that semi-gel electrolyte shows the much better performance for low-rate discharge and the liquid electrolyte is good for high-rate discharge because the reaction rate of gel electrolyte is slower than liquid one for high-rate discharge performance. The test with DOD10% and DOD100% says that 5% silica electrolyte shows much better performance for life efficiency than liquid one. Because semi-gel electrolyte increase the efficiency of gas recombination at the chemical reaction of VRLA battery and it makes minimizing the reduction of electrolyte. Using the 5% silica electrolyte in order to improve the stroage efficiency and life performance for photovoltic and wind power generation, it causes improving by 4.8% for DOD100% and 20% for DOD10%.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.137-143
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• 2005

Oriental melons hold at $38^{\circ}C$ for 48 hours before storage increased their soluble solid, titratable acidity, vitamin C contents and ${\alpha}$-tocopherol activity. These heat treated oriental melons maintained lower production of carbon dioxide, ethylene and acetaldehyde and loss of fresh weight than untreated them, called control, during $3^{\circ}C$ MA storage. After 39 days in storage, the last day of storage, visual quality and internal quality, such as firmness, soluble solid, titratable acidity, vitamin C and ${\alpha}$-tocopherol activity, showed higher in heat treated oriental melons. Especially, Ion leakage of flesh, index of chilling injury, increased remarkably in control, so that heat treatment had to alleviate chilling injury in oriental melon. Moreover, while Alternaria rot was shown in control plot after 25 days in $3^{\circ}C$ MA storage, oriental melons treated heat were not appeared any decomposition after 39 days in $3^{\circ}C$ MA storage. As storage life of oriental melon was calculated by regression equation between visual quality and days in storage, that was longer 8 days in heat treated than control. Consequently, heat treatment that was mild, $38^{\circ}C$ and long period, 48 hours, executed before storage, sterilized surface alleviated chilling injury and lengthened storage life in oriental melons.