• Analytical Science and Technology
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• v.31 no.1
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• pp.47-56
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• 2018

Finding the blood left at a crime scene is very important to reconstruct or solve a criminal case. Although numerous reagents have been developed for use at crime scenes, luminol is the most representative. Bluestar Forensic has been used in recent years, but is expensive and cannot be stored after preparation. This study aims to develop a new luminol reagent that can be stored for a long period of time while maintaining the chemiluminescence intensity at the level of Bluestar Forensic. Because luminol dissolves well in aqueous alkaline solutions, the use of sodium hydroxide in the preparation of luminol reagents can promote the decomposition of hydrogen peroxide. Magnesium sulfate, sodium silicate, and potassium triphosphate have been used as hydrogen peroxide stabilizers. The effects of the addition of these substances on the chemiluminescence emission intensity and the storage period of the luminol reagents were confirmed. The addition of a hydrogen peroxide stabilizer was shown to have no significant affect on the chemiluminescence emissions intensity or stabilized pH of the luminol reagent during storage. It also greatly increases the shelf life of the reagents. The use of magnesium sulfate as a hydrogen peroxide stabilizer is the most appropriate. When sodium perborate is used instead of hydrogen peroxide as an oxidizing agent, there is no significant change in the sensitivity and chemiluminescence emissions intensity, but the storage period is shortened. However, after the reaction with blood, the pH of the mixed solution does not increase significantly, and is judged to be more suitable than a reagent made of hydrogen peroxide.

• Explosives and Blasting
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• v.29 no.2
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• pp.13-31
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• 2011

Air deck charge blast methods have been applied to improve the fragmentation in open cut bench blastings for mining developments. However, during large scale bench blasting operations, there exist some problems such as boulder productions due to explosive charge concentration. Especially, in case of lime stone mining, when air deck method is applied, there has been unintentionally concentrated on charging because the inside holes are often broken by erosion and decomposition. In this study, compared with general blasting, air deck blasting has been focused in lime stone mining. In other to maximize its efficiency, inside hole was examined by endoscope in advance and deck charge using air tube was applied to the section in which concentration might be taken place. Blasting efficiency, fragmentation, charging reduction rate, and total working hours (from charging to blasting) were the main object for comparing, and as a result, air deck was more efficient then the general blasting in all aspects except total working hours.

• Journal of the Korean Society of Safety
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• v.21 no.3 s.75
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• pp.53-58
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• 2006

Following a Mediterranean fruit fly outbreak in South Australia, a bait spray program involving the pesticides like malathion(MAL) was carried out. During the application, dermal exposure was considered for the pest controllers wearing PVC gloves. However there is a lack of information about PVC glove performance like break through times and permeation rates with MAL, therefore, a new analytical method for HPLC-UV was developed. A standard permeation test cell was used in this study. From the results of this study, more than 96% solubility of MAL was provided at 30% isopropyl alcohol in distilled water as a collecting media. However, there was significant decomposition of MAL when the solutions were kept at over $50^{\circ}C$ for 2-3 hours. As a mobile phase, 50% acetonitrile water solution (pH 6.0) gave the greater sensitivity compared with other compositions of acetonitrile solution. The arm section of the gloves had shorter breakthrough times and higher permeation rates compared with the palm. There was no malathion solution breakthrough up to 24 hours using the 1% MAL working strength solution. When the temperature was changed from $22{\pm}1^{\circ}C\;to\;37{\pm}1^{\circ}C$, the breakthrough times were decreased by 14.5% on palm and 37.5% on arm, and permeation rates were increased significantly. The findings of this study indicate that further investigations on used gloves, periods of use and varying working conditions like tasks and seasons should be carried out to assess potential worst case scenarios.

• Smart Structures and Systems
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• v.4 no.1
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• pp.1-17
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• 2008

This study proposes a conceptual framework of in-situ vibration tests and analyses for quality appraisal of non-slender, cast-in-place piles with irregular cross-section configuration. It evaluates a frequency index from vibration recordings to a series of impulse loadings that is related to total soil-resistance forces around a pile, so as to assess if the pile achieves the design requirement in terms of bearing capacity. In particular, in-situ pile-vibration tests in sequential are carried out, in which dropping a weight from different heights generates series impulse loadings with low-to-high amplitudes. The high-amplitude impulse is designed in way that the load will generate equivalent static load that is equal to or larger than the designed bearing capacity of the pile. This study then uses empirical mode decomposition and Hilbert spectral analysis for processing the nonstationary, short-period recordings, so as to single out with accuracy the frequency index. Comparison of the frequency indices identified from the recordings to the series loadings with the design-based one would tell if the total soil resistance force remains linear or nonlinear and subsequently for the quality appraisal of the pile. As an example, this study investigates six data sets collected from the in-situ tests of two piles in Taipu water pump project, Jiangshu Province of China. It concludes that the two piles have the actual axial load capacity higher than the designed bearing capacity. The true bearing capacity of the piles under investigation can be estimated with accuracy if the amplitude of impact loadings is further increased and the analyses are calibrated with the static testing results.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.4
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• pp.458-463
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• 2007

An experimental study on scale-up of Electro-electrodialysis(EED) to increase the efficiency of HI decomposition section in the IS(Iodine-Sulfur) process was carried out. The EED stack extends the effective area of the membrane to 20 times of that formerly used in a single EED unit cell. The experiment was carried out using HIx solution($HI:H_2O:I_2=1:8.4{\sim}9:1.85{\sim}1.9$) at $100^{\circ}C$ and various solution flow rates of 20, 30, 40 and 50 cc/min. The increased HI molality in catholyte after one-pass throughout from the EED stack was 3 mol/kg-$H_2O$, 2.2 mol/kg-$H_2O$, 2 mol/kg-$H_2O$ and 1.37 mol/kg-$H_2O$ at 20, 30, 40 and 50 cc/min, respectively. These values satisfied the target of HI molality(the increase of HI molality: 2 mol/kg-$H_2O$) in the IS process for hydrogen production of 20 L/hr.

• Fire Science and Engineering
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• v.15 no.2
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• pp.1-5
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• 2001

We had investigated combustion properties of starch. Decomposition of starch scavenged by pre-cipitator of spinning factory with temperature were investigated using DSC and TGA. Combustion properties of starch according to amount were checked as temperature variation according to time using spontaneous ignition apparatus. Moreover, combustion properties with blowing or without blowing condition were checked in spontaneous ignition apparatus. As results of thermal analyses, increase in raising temperature causes initial smoldering temperature to move towards low temperature section. In addition, as amount of starch was increased, initial smoldering temperature was lowered. All of combustion forms were smoldering combustion. Initial smoldering temperature was low more slightly with blowing condition than without blowing condition in spontaneous ignition apparatus, which condition made heating value high.

• Fire Science and Engineering
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• v.13 no.1
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• pp.3-10
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• 1999

We had investigated combustion properties of natural textile dusts. Decomposition properles of natural textile dusts scavenged by precipitator of spinning factoη were investigated using D DSC(Differential Scanning Calorimeter) and TGA(Thermogravimetric Analysis) by temperature c changes. Combustion pro야rties of natural textile according to size distribution and amount were c checked as temperature variation according to time using spontan$\infty$us ignition apparatus. M Moreover, combustion properties with blowing or without blowing condition were checked in order to investigate combustion prope$\pi$ies in spontaneous ignition apparatus according to flow c condition of air. As results of thermal analyses, increase in r머sing tern야:rature causes initial smold벼ng t temperature to move towards low temperature section 뻐d i띠디떠 smoldering temperature was d de$\sigma$eased more remarkably in atmosphere than in inert gas and that condition allowed heating v value to increase considerably. In addition, as amount and size distribution of natural textile d dusts were increased, i띠ti머 smoldering temperature was lowered. All of combustion forms were s smoldering combustion. Initial smold밍ing temperature was low more slightly with blowing c condition than without blowing condition in sp$\alpha$ltaneoUS ignition apparatus, which condition m made heatim;!; value high.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.68-78
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• 2006

In the past few years, considerable efforts have been directed towards the further development of Urea-SCR(selective catalytic reduction) technique for diesel-driven vehicle. Although urea possesses considerable advantages over Ammonia$(NH_3)$ in terms of toxicity and handling, its necessary decomposition into Ammonia and carbon dioxide complicates the DeNOx process. Moreover, a mobile SCR system has only a short distance between engine exhaust and the catalyst entrance. Hence, this leads to not enough residence times of urea, and therefore evaporation and thermolysis cannot be completed at the catalyst entrance. This may cause high secondary emissions of Ammonia and isocyanic acid from the reducing agent and also leads to the fact that a considerable section of the catalyst may be misused for the purely thermal steps of water evaporation and thermolysis of urea. Hence the key factor to implementation of SCR technology on automobile is fast thermolysis, good mixing of Ammonia and gas, and reducing Ammonia slip. In this context, this study performs three-dimensional numerical simulation of urea injection of heavy-duty diesel engine under various injection pressure, injector locations and number of injector hole. This study employs Eulerian-Lagrangian approach to consider break-up, evaporation and heat and mass-transfer between droplet and exhaust gas with considering thermolysis and the turbulence dispersion effect of droplet. The SCR-monolith brick has been treated as porous medium. The effect of location and number of hole of urea injector on the uniformity of Ammonia concentration distribution and the amount of water at the entrance of SCR-monolith has been examined in detail under various injection pressures. The present results show useful guidelines for the optimum design of urea injector for reducing Ammonia slip and improving DeNOx performance.

• Journal of the Korean Society of Costume
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• v.60 no.9
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• pp.95-105
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• 2010

The purpose of this study is in allowing thinking about the design development process which is more towards the visual and perceptional aspects related to the form structure by more diverse methods by typology of idea generation. To accomplish such goal, researches in the psychology, pedagogy, engineering, and consilient studies as well as related precedent researches and reference data in architecture, promotion, industrial design, and other art fields and fashion designs are collected and analyzed to see the study trend. In addition, in the content analysis method based on such, the idea generation was classified into types in consideration of relevancy, usefulness, and suitability with fashion. First, a concentrated thinking of a limited space is a method of leading an optimal design by focusing on solving the cause of a problem within a space which generates the problem. Second, plan thinking per section of structure decomposition is a method of dismantling the design problems per organization, thinking type, factor, and characteristic into sub-modules to re-interpret and re-organize the problems in various aspects. Third, an associated thinking through interpreting relationships among vocabularies is a method of selecting the marginal languages that allow a person to come up with concrete forms and the key words related to fashion to import the characteristics and attributes of the marginal languages and thematic relationship between the two terms to search the relevancy. Lastly, the free integrated thinking of language extension is a method of groping integration between other fields and fashion by free integration among the extended terms by extending the vocabularies through inferring metaphorical expressions founded upon individual's memories or knowledge concepts regarding theme words that do not allow concrete forms to come up.

• Polymer(Korea)
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• v.37 no.6
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• pp.677-684
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• 2013

Zinc alginate films were prepared by a film maker from sodium alginate solutions of different weight ratios and then they solidified into 3 wt% content $ZnCl_2$ coagulation solution and washed and dried at a $60^{\circ}C$ oven for 20 min. The characteristics were measured by several methods (antimicrobial activity, viscosity, FTIR, TGA, SEM, EDS, contact angle, tensile strength and solubility) and the film properties were investigated. The antimicrobial test showed that the zinc alginate films result in excellent antimicrobial activity in the two strains (Klebsiella pneumonia, Staphylococcus). The surface of zinc alginate film from the solution of 9 wt% sodium alginate showed more uniform shape than any other films and the cross-section were hard and rough when the films were well-solidified by the $ZnCl_2$ solution. The tensile strength of zinc alginate films increased along with the concentration of sodium alginate solution due to the cross-linking, and the initial thermal decomposition temperature increased gradually.