• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.304-311
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• 2021

This Experiment was conducted to determine the effects of light shield materials when melon grown inside a plastic greenhouse in summer season. The average temperatures were 36.6℃, 34.5℃ and 34.0℃ respectively for the control(non-shield), coating agent, and the white net. The light transmittances were 69% and 75%, respectively inside the greenhouse treated with the coating agent and white net immediately after applicants, compared with that inside the control greenhouse. At the 40 and 80 days after treatment, the light transmittances for the coating agent were 92% and 98%, respectively, indicating it was slowly decomposed and removed, but there was no change in the transmittance for the white net. While the leaf number did not differ among the treatments, the plant height was higher in the white net and shading agent than in control. The weight of the leaves, fresh-weight and dry-weight were no different from that of shading, but it became heavier in the later stages. The marketable fruit yield was increased by 6% for white nets and 5% for the coating agent compared to control, there was no statistical significance. Therefore, coating agent is considered as an effective method to lower temperature during high temperature period, but it is preferable to use it in consideration of cultivation period, because the coating agent is gradually removed.

• Korean Journal of Materials Research
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• v.30 no.11
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• pp.595-600
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• 2020

The photovoltaic properties of perovskite solar cells (PSCs) with a carbon electrode fabricated using different annealing processes are investigated. Perovskite formation (50 ℃, 60 min) using a hot-plate and an oven is carried out on cells with a glass/fluorine doped TiO₂/TiO₂/ZrO₂/carbon structure, and the photovoltaic properties of the PSCs are analyzed using a solar simulator. The microstructures of the PSCs are characterized using an optical microscope, a field emission scanning electron microscope, and an electron probe micro-analyzer (EPMA). Photovoltaic analysis shows that the energy conversion efficiency of the samples fabricated using the hot-plate and the oven processes are 2.08% and 6.90%, respectively. Based on the microstructure of the samples and the results of the EPMA, perovskite is formed locally on the carbon electrode surface as the γ-butyrolactone (GBL) solvent evaporates and moves to the top of the carbon electrode due to heat from the bottom of the sample during the hot plate process. When the oven process is used, perovskite forms evenly inside the carbon electrode, as the GBL solvent evaporates extremely slowly because heat is supplied from all directions. The importance of the even formation of perovskite inside the carbon electrode is emphasized, and the feasibility of oven annealing is confirmed for PSCs with carbon electrodes.

• Fashion & Textile Research Journal
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• v.11 no.1
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• pp.121-129
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• 2009

Nowadays, global interest is being placed on research and development of smart clothing which is expected to create a high added-value industry in the future. The purpose of this research is to develop smart pants with vibrating massage functions that have excellent outer appearances and provide comfort to wearers and assess outer appearance, comfort, and massaging effects of smart pants. As the results of this research, smart pants where vibrating devices which are mainly composed of vibrating motor, controller, and switch are attached were completed. Vibrating motors were fixed on a thin and light non-woven fabric material, covered with a mesh material, and attached by snaps to the experiment pants. Switch was attached to the inside of a pocket, and batteries were positioned inside of pockets. Ten subjects marked their satisfaction of wearing smart pants on a 5-point scale. Noticeable changes in outer appearance when vibrating motors operate turned out to be low. Wearer's comfort in back waist and front thigh parts where vibrating motors were attached turned out to be high-satisfied. Massaging effects of smart pants turned out to be high. Attaching and detaching vibrating devices turned out to be convenient. Lining materials used for smart paints were effective in blocking electromagnetic waves generated from vibrating devices.

• Fashion & Textile Research Journal
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• v.1 no.1
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• pp.12-17
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• 1999

The actual clothing conditions were surveyed to diagnose clothing condition of collegians in the view point of adaptation to the thermal environment in fall. Then, clothing climate, physiological responses, and subjective sensation were investigated through wearing trials on human subjects in climatic chamber based on the results from the survey. Factors to evaluate validity of clothing condition were clothing weight, clothing climate, physiological responses of human body, and subjective sensation. Adaptability of this research to thermal environment was compared to the results of Toda's and Duno's of Japan, Chung's results of Korea rural area, and Winslow's clo value. The standard values for wearing trials were values at comfortable zone, such as $32{\pm}1^{\circ}C$ of temperature and $50{\pm}10%$ of humidity inside clothing, $36.5{\sim}37.3^{\circ}C$ of ear temperature and $32.2{\sim}34.3^{\circ}C$ of mean skin temperature. Clothing weight per body surface area was 680.9 $g/m^2$ in male and 526.7 $g/m^2$ in women. Cold resistance ability of collegians was superior to Japanese and American, and similar to rural male in Korea. According to the examination of clothing adaptability with clothing weight from the investigation on physiological responses and the actual clothing conditions survey, following were found. Temperature inside clothing ($29.8{\sim}32.3^{\circ}C$) was normal, and humidity inside clothing (32.2~54.8%) was at comfortable zone. Mean skin temperature was at its comfortable zone. Therefore, 615 $g/m^2$ in male and 525 $g/m^2$ in female were a desirable wearing condition.

• Korean Journal of Materials Research
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• v.30 no.10
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• pp.533-541
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• 2020

UO₂ kernels, a key component of fuel elements for high temperature gas cooled reactors, have usually been prepared by sol-gel methods. Sol-gel processes have a number of advantages, such as simple processes and facilities, and higher sphericity and density. In this study, to produce 900 ㎛-sized UO₂ particles using an external gelation process, contact length extension of the NH₃ gas of the broth droplets pass and the improvement of the gelation device capable of spraying 14 M-NH₄OH solution are used to form 3,000 ㎛-sized liquid droplets. To produce high-sphericity and high-density UO₂ particles, HMTA, which promotes the gelation reaction in the uranium broth solution, is added to diffuse ammonium ions from the outside of the gelation solution during the aging process and generate ammonium ions from the inside of the ADU gel particles. Sufficient gelation inside of ADU gel particles is achieved, and the density of the UO₂ spheres that undergo the subsequent treatment is 10.78 g/㎤; the sphericity is analyzed and found to be 0.948, indicating good experimental results.

• Journal of Powder Materials
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• v.27 no.6
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• pp.477-483
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• 2020

Metal-organic frameworks (MOFs) are of significant interest because of their high porosity, which facilitates their utilization in gas storage and catalysis. To enhance their current properties in these applications, it is necessary to elucidate the interactions between molecules in a confined environment that differ from those in bulk conditions. Herein, we study the confined molecular interaction by investigating the solvent-dependent photophysical properties of two different-sized molecules inside MOF-5. Ruthenium tris-bipyridine (Rubpy) and coumarin 153 (C153) are encapsulated in MOF-5. Rubpy with MOF-5 (Rubpy@MOF) is prepared by building MOF-5 around it, resulting in limited space for solvent molecules in the pores. The smaller C153 is encapsulated in the preformed MOF-5 (C153@MOF) by simply soaking the MOF in a concentrated C153 solution. C153@MOF permits more space for solvent molecules in the pore. Their characteristic absorption and emission spectra are examined to elucidate the confined molecular interactions. Rubpy@MOF and C153@MOF exhibit different spectral shifts compared to the guest molecules under bulk conditions. This discrepancy is attributed to the different micro-environments inside the pores, derived from confined host-guest interactions in the interplay of solvent molecules.

• Ocean and Polar Research
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• v.28 no.3
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• pp.293-303
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• 2006

The topography of the sea floor and textural characteristics of surface sediments are documented in areas off sectors 1,2, and 4 of the Saemangeum dyke and inside the dyke. These were investigated during the years 2002 to 2005, when the dyke construction almost came to an end, and were compared with natural topographic analogs before the dyke construction from the maritime maps of 1982 and 1994. Along and across the dyke are a number of erosional troughs formed by intensified currents during the dyke construction. The sea floor off sector 4 has undergone gradual accumulation of sands moving from the north by currents varying in direction from normal to parallel to the dyke. This is in a strong contrast with a slight erosional environment prevailing over the sea floor before dyke construction. off sectors 1 and 2, a topography with an alterative pattern of erosional troughs and sand shoals develops normal to the dyke. Eroded materials from the troughs seem to have added to the sand shoals. As a result, the troughs, former natural tidal channels, have become increasingly deeper, whereas the sand shoals have become somewhat shallower. The sea floor inside the dyke has also been remarkably shallower with expanding tidal flats due to trapping by the dyke of continuous sediment input from the Dongjin and Mangyeong rivers. Sands, all of which are considered to have originated originally from the two rivers, dominate the entire Saemangeum area.

• International Journal of Costume and Fashion
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• v.9 no.1
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• pp.34-43
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• 2009

This study compared the thermal comfort of indoor clothing from Tencel material that is getting higher in demand due to being eco-friendly with superior wettability, with that from Polyester material that despite being most widely used for indoor clothing, rapidly discharges body sweat due to low wettability. The experiments were performed in the two manners, objective evaluation under the conditions of an artificial climate chamber and subjective evaluation of wearing the given clothes at home followed by filling in the questionnaire. Subjects were 8 healthy elderly women in their 60's who spend majority of their time at home rather than in social activities, and comparison was made on skin temperature and humidity inside clothing at exercise and relaxation states under early summer environment. Based on these results, wearing Tencel material clothing maintained cooler temperatures under warm environment rather than when wearing Polyester material clothing, thus enabling activities under more comfortable state. Regarding humidity inside clothing, parts with twofold clothing did not show difference between Tencel and Polyester, but the onefold arm showed lower when wearing Tencel. With this results, Tencel is regarded as more comfortable and nicer than Polyester.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.2
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• pp.111-117
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• 2008

The new type phoswich detector consisting of the ZnS(Ag) and plastic scintillator for alpha/beta-ray simultaneous counting was developed for monitoring radiological contamination inside pipes. The detection performance was estimated using the PSD (pulse shape discrimination) method as a function of distance between the scintillator and radioactive source. The attenuation of particles traveling through a thin film for preventing the detector from being contaminated was experimentally estimated. It is concluded from our investigation that the phoswich detector developed can provide a sufficient alpha/beta-ray discrimination. The application of a thin film for preventing the detector from being contaminated was proven to be feasible.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1887-1898
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• 2018

In this paper, a method to classify insider threat activity is introduced. The internal threats help detecting anomalous activity in the procedure performed by the user in an organization. When an anomalous value deviating from the overall behavior is displayed, we consider it as an inside threat for classification as an inside intimidator. To solve the situation, Markov Chain Model is employed. The Markov Chain Model shows the next state value through an arbitrary variable affected by the previous event. Similarly, the current activity can also be predicted based on the previous activity for the insider threat activity. A method was studied where the change items for such state are defined by a transition probability, and classified as detection of anomaly of the inside threat through values for a probability variable. We use the properties of the Markov chains to list the behavior of the user over time and to classify which state they belong to. Sequential data sets were generated according to the influence of n occurrences of Markov attribute and classified by machine learning algorithm. In the experiment, only 15% of the Cert: insider threat dataset was applied, and the result was 97% accuracy except for NaiveBayes. As a result of our research, it was confirmed that the Markov Chain Model can classify insider threats and can be fully utilized for user behavior classification.