• Proceedings of the Korean Information Science Society Conference
• /
• 2004.04b
• /
• pp.412-414
• /
• 2004

요구사항 추출 단계에서 고객의 요구의 일부가 반영되지 않거나 명확히 기술하지 않은 요구사항은 개발단계에서 많은 수정 작업이 요구되고, 심지어 그 프로젝트가 실패하게 되는 요인이 된다. 이와 같은 요구사항의 문제로 인한 추가적인 비용은 전체 개발비용의 30~50%나 소요된다(Boehm 과 Papaccio 1988). 하지만 요구사항 추출 단계에서 고객이 원하는 요구를 가능한 많이 추출하고 검증함으로써 추가적인 변경으로 인한 개발비용의 비용을 줄일 수 있다. 고객의 요구를 정확히 반영하기 위해서는 요구사항 추출 과정에서 고객의 참여가 매우 중요한데 본 논문에서는 성공적인 요구사항 추출 및 검증과 명세를 위해 사용자의 참여를 높이기 위한 웹 기반 요구사항 추출 도구를 소개하고 명확한 요구사항을 표현할 수 있기 위해 다이어그램을 통합한 요구사랑 관리도구를 제시한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2012.11a
• /
• pp.1497-1499
• /
• 2012

전통적인 소프트웨어 개발에서는 초기 요구사항을 정확히 판단하고 분석하는 것이 중요하다. 이를 위해 B.Boehm은 가치혁신 요구공학을 제안하지만, 이는 기존의 개발 방법 기반이다. 본 논문에서는 가치 혁신 요구공학 개선을 위해, 유스케이스 기반의 요구공학 방법을 제시와, 요구사항과 유스케이스의 우선순위 도출 방법을 제안한다. 이를 위해 어려운 시스템 요소(하드웨어와 소프트웨어)를 기본 단위인 유스케이스 요소와, 유스케이스 점수(Use Case Point) 개념을 적용하여 유스케이스 중요도를 도출한다. 그 기본 단위 내의 분석을 통해 쉽게 요구사항 추출 및 우선순위화를 한다. 이는 테스트 단계에서 우선순위화된 테스트 케이스를 적용이 가능한다고 본다.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.10
• /
• pp.193-202
• /
• 2012

The purpose of this study is to examine the moderating effect of family resilience in the relationship of abuse experience, self-esteem, family resilience, and suicide, and make suggestion for policies to improve family resilience to prevent suicide of the youth with abuse experience. For this, a survey was conducted with 600 people at middle and high schools in three districts in Jeollanamdo, and, except 53 copies, total 547 copies used. The scales used child abuse of Murray A. Straus (1979), suicide of Beck, Kovacs & Weissmen(1979), self-esteem of Coopersmith(1967), and family resilience of Boehm (2007). The results: First, 54.2% of experienced abuse, and, as for the suicide frequency based on abuse types, physical abuse scored high. Second, the regression analysis showed that abuse experience has a direct positive effect on suicide, and higher abuse experience led to more suicide. Also, abuse experience turned out to have indirect effect on suicide through self-esteem, which proves the mediated effect of self-esteem. Third, family resilience was proven to have mediated effect as abuse experience has a negative effect on suicide, and high self-esteem has a negative effect on suicide.

• Journal of the Korean Wood Science and Technology
• /
• v.33 no.6 s.134
• /
• pp.63-70
• /
• 2005

The purpose of this study was to investigate how to modify the physical properties of cellulose after thermal treatment. Cellulose was treated between $225^{\circ}C$ and $325^{\circ}C$ for 3 hrs under air flow, and then the thermally treated cellulose was measured to specific surface area, constitute elements, consumption ofacid and base, as well as the adsorption capacity of ethylamine vapor. The higher was the treating temperature from $225^{\circ}C$ to $325^{\circ}C$, the lower was the total yield of cellulose. Elemental analysis revealed that carbon content in thermally treated cellulose was gradually increased in proportion to temperature increment. The amount of acidic functional groups tended to increase up to $300^{\circ}C$, after then to be lowered slightly. In principle, no alkaline functional groups were found in thermally treated cellulose. In case of treatment with $325^{\circ}C$, only a few amount of alkaline functional groups were detectable. Specific surface area of thermally treated cellulose are determined to $1.9m^2/g$, which value can become higher when the treated temperature rises. The thermally treated cellulose at $275^{\circ}C$ shows the highest adsorption capacity of ethylamine at $40^{\circ}C$ for 4 hrs. Solubility of those two celluloses with WPG (Weight Percent Gain) value of 113% and 108%, respectively, was determined to almost 100%. X-ray diffractogram of thermally treated cellulose suggested that the crystalline structure of cellulose began to be destroyed at the temperature of $275^{\circ}C$. As a conclusion, changes of such a physical properties make it possible to weaken inter and/or intra hydrogen bond in crystal region of cellulose macromolecules. When thermally treated cellulose adsorbs ethylamine, it turns to be well soluble to water.

• Polymer(Korea)
• /
• v.27 no.5
• /
• pp.464-469
• /
• 2003

In this work, the fragrant oil release behavior of poly($\varepsilon$-caprolactone) (PCL) microcapsules containing SiO$_2$ was investigated. The SiO$_2$ was chemically treated in 10, 20, and 30 wt% hydrochloric acid and sodium hydroxide. The acid and base values were determined by Boehm's titration technique and $N_2$/77 K adsorption isotherm characteristics, the specific surface area and total pore volume were studied by BET. The PCL microcapsules containing SiO$_2$ and fragrant oil were prepared by oil-in-water (o/w) emulsion solvent evaporation method. The shape and surface of PCL microcapsules were observed using image analyzer and scanning electron microscope (SEM). The fragrant oil release behavior of PCL microcapsules was characterized using UV/vis. spectra. The average diameters of PCL microcapsules were decreased from 35 to 21 $\mu$m with increasing stirring rate. It was found that in the case of acidic treatment the fragrant oil adsorption capacity and release rate were increased due to the increase of specific surface area and acid value. In the case of basic treatment, the fragrant oil adsorption capacity and release rate were decreased due to the decrease of sp ecific surface area and the increase of acid-base interactions between SiO$_2$-NaOH and fragrant oil with increasing base value of SiO$_2$.

• Carbon letters
• /
• v.12 no.3
• /
• pp.152-161
• /
• 2011

Activated carbon was prepared from pre-carbonized petroleum coke. Textural properties were determined from studies of the adsorption of nitrogen at 77 K and the surface chemistry was obtained using the Fourier-transform infrared spectrometer technique and the Boehm titration process. The adsorption of three aromatic compounds, namely phenol (P), p-nitrophenol (PNP) and benzoic acid (BA) onto APC in aqueous solution was studied in a batch system with respect to contact time, pH, initial concentration of solutes and temperature. Active carbon APC obtained was found to possess a high surface area and a predominantly microporous structure; it also had an acidic surface character. The experimental data fitted the pseudo-second-order kinetic model well; also, the intraparticle diffusion was the only controlling process in determining the adsorption of the three pollutants investigated. The adsorption data fit well with the Langmuir and Freundlich models. The uptake of the three pollutants was found to be strongly dependent on the pH value and the temperature of the solution. Most of the experiments were conducted at pH 7; the $pH_{(PZC)}$ of the active carbon under study was 5.0; the surface of the active carbon was negatively charged. The thermodynamic parameters evaluated for APC revealed that the adsorption of P was spontaneous and exothermic in nature, while PNP and BA showed no-spontaneity of the adsorption process and that process was endothermic in nature.

• Carbon letters
• /
• v.14 no.1
• /
• pp.14-21
• /
• 2013

Physically and chemically activated carbons (ACs) exhibited high adsorption capacities for organic and inorganic pollutants compared with other adsorbents due to their expanded surface areas and wide pore volume distribution. In this work, seven steam-ACs with different burn-off have been prepared from cotton stalks. The textural properties of these sorbents were determined using nitrogen adsorption at $-196^{\circ}C$. The chemistry of the surface of the present sorbents was characterized by determining the surface functional C-O groups using Fourier transform infrared spectroscopy, surface pH, $pH_{pzc}$, and Boehm's acid-base neutralization method. The textural properties and the morphology of the sorbent surface depend on the percentage of burn-off. The surface acidity and surface basicity are related to the burn-off percentage. A theoretical model was developed to find a mathematical expression that relates the % burn-off to ash content, surface area, and mean pore radius. Also, the chemistry of the carbon surface is related to the % burn-off. A mathematical expression was proposed where % burn-off was taken as an independent factor and the other variable as a dependent factor. This expression allows the choice of the value of % burn-off with required steam-AC properties.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.4
• /
• pp.1321-1326
• /
• 2011

In this work, the effects of different surface functional groups on the elemental mercury adsorption of porous carbons modified by chemical treatments were investigated. The surface properties of the treated carbons were observed by Boehm's titration and X-ray photoelectron spectroscopy (XPS). It was found that the textural properties, including specific surface area and pore structures, slightly decreased after the treatments, while the oxygen content of the ACs was predominantly enhanced. Elemental mercury adsorption behaviors of the acidtreated ACs were found to be four or three times better than those of non-treated ACs or base-treated ACs, respectively. This result indicates that the different compositions of surface functional groups can lead to the high elemental mercury adsorption capacity of the ACs. In case of the acid-treated ACs, the $R_{C=O}/R_{C-O}$ and $R_{COOH}/R_{C-O}$ showed higher values than those of other samples, indicating that there is a considerable relationship between mercury adsorption and surface functional groups on the ACs.

• Journal of Korean Society for Atmospheric Environment
• /
• v.21 no.2
• /
• pp.155-160
• /
• 2005

Removal of methyl mercaptan was investigated using adsorption on virgin activated carbon (VAC) and modified activated carbons with acidic chemicals in the present work. CAC, NAC, AAC and SAC were represented as activated carbons modified with HCI, HNO$_{3}$, CH$_{3}$COOH and H$_{2}$S0$_{4}$ ,respectively The pore structures were evaluated using nitrogen isotherm. The surface properties of virgin activated carbon and modified activated carbons were characterized by EA, pH of carbon surface and acid value from Boehm titration. The modification of activated carbon with acidic chemicals resulted in a decrease in BET surface area, micropore volume and surface pH, but an increase in acid value. The order of the adsorption capacity of activated carbons was NAC>AAC>SAC>CAC>VAC, and in agreement with that of acid value of activated carbons, whereas in disagreement with that of micropore volume of activated carbons. It appeared that chemical adsorption played an important role in methyl mercaptan on modified activated carbons with acidic chemicals compared to virgin activated carbon. Modifying activated carbon with acidic chemicals enabled to significantly enhance removal of methyl mercaptan.

• Transactions on Electrical and Electronic Materials
• /
• v.15 no.2
• /
• pp.81-86
• /
• 2014

The process parameter in optimized KOH alkali activation of soft carbon series coke material in high purity was set with DOE experiments design. The activated carbon was produced by performing the activation process based on the set process parameters. The specific surface area was measured and pore size was analyzed by $N_2$ absorption method for the produced activated carbon. The surface functional group was analyzed by Boehm method and metal impurities were analyzed by XRF method. The specific surface area was increased over 2,000 $m^2/g$ as the mixing ratio of activation agent increased. The micro pores in $5{\sim}15{\AA}$ and surface functional group under 0.4 meq/g were obtained. The contents of the metal impurity in activated carbon which is the factor for reducing the electrochemical characteristics was reduced less than 100 ppm through the cleansing process optimization. The electrochemical characteristics of activated carbon in 38.5 F/g and 26.6 F/cc were checked through the impedance measuring with cyclic voltammetry scan rate in 50~300 mV/s and frequency in 10 mHz ~100 kHz. The activated carbon was made in the optimized activation process conditions of activation time in 40 minutes, mixing ratio of activation agent in 4.5 : 1.0 and heat treatment temperature over $650^{\circ}C$.