• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.2
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• pp.187-201
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• 1996

This study was to evaluate the efficiency of diffusive monitor using activated carbon fiber(ACF, KF-1500) in measuring airborne organic solvents. The following characteristics were identified and studied as critical to the performance of diffusive monitor; recovery, sampling rate, face velocity, reverse diffusion and storage stability. For the evaluation of the performance of this monitor, MIBK, PCE, toluene were used as organic solvents. In the sampling rate experiments, eight kinds of solvents (n-hexane, MEK, DIBK, MCF, TCE, CB, xylene, cumene) as well as the above solvents were used. The results were as follows: 1. The desorption efficiencies(DE's) of ACF diffusive monitor ranged from 83 % to 101 %. In contrast, those of coconut shell charcoal ranged from 78 % to 102 %. Especially, the DE's of ACF for the polar solvents such as MEK were superior to those of charcoal. 2. Experimental sampling rates on ACF were average 42ml/min(37-46ml/min) for 11 organic solvents at $24{\pm}2^{\circ}C$, $50{\pm}5%RH$. However ideal sampling rates(DA/L) were 33 % higher than experimental sampling rates. 3. The initial response(15~16 min) of the testing monitor was 2 times higher than the actual concentration determined by the reference methods at $24{\pm}2^{\circ}C$, $8{\pm}5%RH$ and $80{\pm}5%RH$. Within 1 hours, the curve reached a linear horizontal line at low humidity condition. But sampling efficiencies decreased with respect to time at high humidity condition. And sampling efficiencies were higher at high humidity condition than low humidity condition for MIBK. 4. At very low velocity (less than 0.02 m/sec), the concentration of ACF diffusive monitor were poorly estimated. But ACF diffusive monitor were not affected at higher velocity(0.2 m/sec-0.6 m/sec). 5. There was no significant reverse diffusion when the ACF monitors were exposed to clean air for 2 hours after being exposed for 2 hours at the level of 1 TLV. 6. There was no significant sample loss during 3 weeks of storage at room temperature and 5 weeks of storage at refrigeration.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.415-424
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• 2014

This study was carried out to determine the effect of storage condition, such as temperature or relative humidity (RH) in home-style refrigerator, on the change of quality traits and storage characteristics of Hanwoo M. longissimus to find out the condition for prolongation of shelf-life with maintaining the meat quality for consumers. Samples were sliced in $1{\pm}0.2cm$ thickness, and packed in foamed polystyrene tray with linear low-density polyethylene (LLD-PE) film to simulate the pre-packed Hanwoo loin sold in retail market, then stored in home-style refrigerator ($5^{\circ}C$/17% RH, Control), and chambers of $5^{\circ}C$/55% RH (T1), $5^{\circ}C$/85% RH (T2), and $-1^{\circ}C$/99% RH (T3), respectively. Quality traits (color, pH, water holding capacity, shear force and grilling loss) and storage characteristics (thiobarbituric acid reactive substances, volatile basic nitrogen and total microbes) were measured at 1, 4, 7, 14 and 21 days after storage. Lightness of Hanwoo loin stored in T1, T2 and T3 were higher than that of control until 14 days of storage, however at the end of storage (21 days) control showed significantly higher than other treatments (p<0.05). Redness and Yellowness of Hanwoo loin samples stored in T1 and T3 were significantly higher than others during all storage period (p<0.05). The water holding capacity (WHC) of control was significantly higher than others until 14 days of storage (p<0.05), however, Hanwoo loin stored in T2 was the highest ($63.64{\pm}7.62kg/cm^2$) at 21 days of storage. Hanwoo loin stored in T1 showed significantly lower shear force than others during all storage period (p<0.05). There was no consistent tendency in pH and grilling loss during storage in all treatments. Hanwoo loin stored in T1 showed lower TBARS value than others during storage period, however there was a rapid increase to $0.34{\pm}0.27mg$ malonaldehyde/kg meat at 21 days of storage. And, all the treated samples (from T1 to T3) showed significantly lower VBN values at 21 days of storage (p<0.05). The population of total aerobic microbes were significantly increased in all treatments as storage period increasing, and the population of T3 ($2.28{\pm}0.57logCFU/g$) was the lowest at 21 days of storage (p<0.05). From those results, it could be predicted the better storage condition to maintain the meat quality and prolong the shelf-life of Hanwoo loin by lowering the temperature and adjusting the humidity about 55%.

• Tunnel and Underground Space
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• v.6 no.4
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• pp.335-341
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• 1996

This fundamental study analyzes the relationship between rock thermal properties and psychrometric properties in underground space and has a ultimate goal to develope technologies for predicting major environmental variables. The study is divided into 2 subjects (1) developement of a basic model for predicting temperature and humidity, (2) analysis of the validity of the model through application to a local underground storage space for military supplies. The basic model is built for the network of tunnel-shaped underground spaces. The model takes into account rock thermal properties and changes in moisture content in the air due to condensation/evaporation on the rock surface. Using lumped-parameter analytical method, heat flux from or to the surrounding rock is calculated and then the psychrometric properties(air quantity, pressure, temperature, humidity) are estimated through network simulation. The model can be utilized regardless of the tunnel type. The study site is a local storage space built in rock, mainly granite gneiss and quartz-porphyry. It is a U-shaped tunnel, 593.5m long and 6x6.5m wide. Relative humidity inside has to be strictly controlled under 55% to avoid erosion of a certain types of supplies stored in 6 chambers with the capacity of 300~1.000 ton. The thermal conductivity varies between 2.734 and 2.779W/m$^{\circ}C$ and the thermal diffusivity is in the range of 1.119 and $1.152{\times}10^{-6}\;m^2/s$ the specific heat between 910 and $920\;J/kg^{\circ}C$. Relative errors of the predicted values of dry/wet temperature and relative humidity are 0.8~3.0%, 0~7.5% and 0~7.0%, respectively. Apparent errors associated with the rock surface temperature seems to be partly due to the intrinsic limitations in the infrared thermometer used in this study.

• Food Science and Preservation
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• v.7 no.1
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• pp.29-32
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• 2000

Storage life of grape cultivars including Kyoho(Inzuka), which were imported from Japan and are cultivated after adoption as farming application, were examined. The stu요 was accomplished with grapes packed by PE film under storage temperature $0^{\circ}C$ and humidity 90%RH loss of weight, Weight loss and occurrence of abnormal fruit increased in proportion to storage days. Abnormal fruits of Kyoho(izuka), North Black , and Seto giants increased rapidly after 60 days of storage, resulting in slight deterioration of commercial value. Similarly, this phenomenon of Campbell early , Takasumi , and Aki Queen occurred after 70 days of storage. External appearance decreased rapidly after 60 days of storage, resulting in 7.0 index of Takatsuma and Aki Queen , 3.0-3.6 of North Black and Seto Giants, and 5.0 of Campbell Early, kyoho (izuka0, and takasumi after 80 days of storage. Soluble solide content and titratable acidity showed a trend to be decreased with lapse of storage. Sugar/acid ratio shwoed much fluctuation between different grapes. Possible storage days, in view of more 70% merchandise berry ratio, were 90 days of Takatsuma and Aki Queen , 70 days of Campbell Early, 60 days of Takasumi , kyoho(Iizuka), and Seto giants, below 60 days of North Black.

• Journal of Biosystems Engineering
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• v.5 no.1
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• pp.33-42
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• 1980

This study was carried out to investigate the actual environmental paddy storage conditions in conventional Korean farm warehouses. The paddy storage conditions by the locations and sizes of warehouses were figured out. The effectiveness of the small insulated box for storing paddy was also examined. Observations were made at sixteen different warehouses located in Moonsan-Myeon, Jinyandg-gun, Gyungnam Province from July lst to September 28 th, the period which was considered to be the worst for storing grains. The results are as follows ; 1. the average temperatures of rough rice and air inside the warehouse were 0.9 and 0.7$^\circ$ higher than the outside air temperature. 2. The average relative humidity in warehouses was 1.5percent higher than that of the atomosphere. This fact resulted in the increased moisture content of grains. Therefore, the ventilation for equalizing the relative humidity of inside and outside of warehouses was required. 3. The dry matter of stored rough rice was decreased by 1.1 percent in average druing the observation period. In order to reduce the dry matter loss, application of new grain storing method ;hermetic storage or filling inert gas storage, was highly recommended. 4. Environmental conditions for storing rough rice in a warehouse located in a sloping site are, in general , better than those of a warehouse located in a flat site. But as far as the dry matter of rough rice was concerned, above situation is not always satisfactory. Because it is fairly frequent to observe the higher rate of moisture absorption by grains stored in a warehouse located in a sloping site. 5. Environmental conditions for storing rough rice in a large-scale warehouse were better than those in a small size warehouse. Therefore, it is advisible for farmers to store their grins in the large-scale warehouses commonly used by villagers. 6. It was undesirable to store rough in a insulated box.

• Journal of Conservation Science
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• v.29 no.4
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• pp.421-435
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• 2013

The purpose of this study is to suggest environmental guidelines for the conservation of ceramics excavated from underwater. Accordingly, the conditional change of the soluble salt on surface of the excavated ceramics was examined by changing the relative humidity. Examining the relative ratio [high humidity(RH70%+RH80%)/low humidity(RH20%+ RH40%)] for 24 weeks using accumulated conductivity(${\mu}s/cm$), the result showed that the amount of ion elution increased more in high humidity than in low humidity. In particular, the ion elution increased significantly within the celadon sample. In addition, comparing the accumulated conductivity and physical characteristics of the samples in high humidity, the results indicated that the amount of the ion elution is proportioned to the increased rate of the sample's absorption capacity and porosity. Ceramics excavated from underwater has risks of the secondary physical and chemical attacks from remaining salts. Therefore, it is suggested these ceramics be stored in a storage which maintains proper temperature and low humidity conditions. Also, the collections need to be pre-classified according to the properties of the materials.

• Journal of Korean Society for Quality Management
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• v.40 no.3
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• pp.270-277
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• 2012

Purpose: In this paper, storage lifetime of delay system in the fuse of 81MM illuminating projectile is estimated. Methods: Accelerated degradation testings of tungsten delay system using both temperature and humidity stresses were performed, and then delay time increase of the systems were analyzed as degradation data based on distribution-based degradation processes. Results: The estimated storage lifetime of detonator is between 11.8 years and 17.6 years with each stress-life relationship. Conclusion: Comparing with field data, storage lifetime of 90% reliability is about 12 years.

• Journal of Biosystems Engineering
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• v.25 no.1
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• pp.33-38
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• 2000

This study was performed to investigate airtight storage characteristics of rough rice using airtight flexible pve container. A storage test of rough rice of 4 tonnes was carried out to determine the changes of gas composition of air in the container, grain moisture content, air temperature and relative humidity , the presence of insects ,germination rate, crack ratio , fat acidity , 1000-kernel weight, and brown rice recovery over storage period of 5 months in Suwon. Concentration of oxygen was decreased from 20% to 16% and carbon dioxide was increased of from 0.03% to 1.6%. The grain moisture content was decreased from 14.4%(w.b) to 14.1%(w.b) for 5 months storage period . Insect population levels were low but these increased after 5 months storage. Most of insects were dead, Fat acidity increased from 7.5(mg KOH/100g) to 10.2(mg KOH/100g). Other storage factors such as germination rate, brown rice recovery and 1000-kernel , and 1000-kernel weight slightly decreased and crack ratio was slightly increased. Qualities of rough rice during 5 months storage period under hemetic air conditions were maintained fairly good considering the above changes of quality factors during storage.

• Journal of the Korean Society for Nondestructive Testing
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• v.12 no.2
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• pp.30-35
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• 1992

High quality of turbine babbit bearing has to be maintained for smooth operation of power plants. So in the research center of the Korea Electric Power Company, Ultrasonic testing has been peformed on the spare part of babbit bearing during past ten years. Since separation between babbit bearing and base metal was seen for most of the bearings in stock, investigation has begun in order to see the effect on temperature and humidity variation of the separation, and thus searching for the optimum storage method.

• Korean Institute of Interior Design Journal
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• v.15 no.3 s.56
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• pp.144-154
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• 2006

Except the time when relics of a museum are exhibited or loaned to the public, they are stored in a storage. In addition, it is common view that collections are exhibited a few of total stored collections in a museum. Therefore, the environmental condition of a storage is an important factor. Hereby, the purpose of this study is to suggest the design guidelines of a storage for conservation of relics in a museum. The results from this study are as follows briefly. First, location of storages has to be located and centralized above ground against preservation environment and additional renovation. Second, for storage size, It is reasonable to secure long-term experimental data after planning about 20% of whole section in present domestic situation. Third, in order to prevent environmental deterioration due to short storage floor space, adequate storage height has to be secured against a mezzanine deck and spare storages need to be planned. Where a mezzanine deck is designed, detailed plans have to be supported for equal micro climate in a storage. Fourth, in respect of environmental control of storages, finish materials with adjustment ability on relative humidity have to be used after the system is installed jointly direct and indirect way by air chamber, considering domestic condition for management of intermittent ventilation.