• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.79-84
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• 2003

The main objective of this study was to investigate the chemical characteristics of post-harvest biomass burning aerosols from field burning of barley straw in late spring and rice straw in late fall in rural area in Korea. 12-hr integrated intensive sampling of $PM_{10}$ and $PM_{2.5}$ biomass burning aerosols had been conducted continuously at Gwangju, Korea 4-15 June 2001 and 8 October-14 November 2002. The fine and coarse particles of biomass burning aerosols were collected for mass, ionic, elemental, and carbonaceous species analysis. Average fine and coarse mass concentrations of biomass burning aerosols were measured to be 129.6, 24.2 ${{\mu}gm}^{-3}$ in June 2001 and 47.1, 33.2 ${{\mu}gm}^{-3}$ in October to November 2002, respectively. Exceptionally high level of $PM_{2.5}$ concentration up to 157.8 ${{\mu}gm}^{-3}$ well above 24-hour standard was observed during the biomass burning event days under stagnant atmosphere condition. During biomass burning periods dominant ionic species were $Cl^{-}$, ${NO_3}^{-}$, ${SO_4}^{2-}$, and ${NH_4}^{+}$ in fine and coarse mode. In the fine mode $Cl^{-}$ and ${KCl}^{+}$ were unusually rich due to the high content of the semiarid vegetation. High OC values and OC/EC ratios were also measured during the biomass burning periods. Increased amount of fine aerosols with high enrichment, which were originated from biomass burning of post-harvest agricultural waste, resulted in extremely severe particulate air pollution and visibility degradation in the region. Particulate matters from open field burning of agricultural wastes cause great adverse impact on local air quality and regional climate.

• Asian Pacific Journal of Cancer Prevention
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• 제15권14호
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• pp.5697-5699
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• 2014

Objective: To investigate the optimal timing of radiotherapy with alternating/sequential radio-chemotherapy for limited-stage small cell lung cancer (LS-SCLC). Methods: 91 patients with LS-SCLC were retrospectively analyzed and divided into two groups according to the number of chemotherapy cycles before radiotherapy. If the patient received radiotherapy after 3 cycles or fewer cycles of chemotherapy, classification was into the early group, if not, into the late group. All patients received 6 cycles of standard chemotherapy (EP/EC) and conventional radiotherapy (56 gy~ 60 gy/28 f ~30 f). Results: The response rate (RR) of the early and late groups were 85.7% and 81.6%, respectively, with no significant difference (p>0.05). In contrast, the progression-free survival (PFS) in the early group was better than that in the late group (11.8 months vs 9.86 months), and the difference was significant (p<0.05). There was no significant difference between two groups in adverse reactions, which gastrointestinal irritation and bone marrow suppression being the most common (p>0.05). Conclusions: Radiotherapy after 3 cycles or fewer cycles of chemotherapy does not bring significant benefits for RR of patients with LS-SCLC, but it could significantly prolong their PFS without increase in adverse reactions.

• 한국통신학회논문지
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• 제23권6호
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• pp.1526-1537
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• 1998

화소영역에서의 처리방법이 주를 이루고 있는 Multipoint Control Unit(MCU)의 화면분할(Split-Screen) 처리기능은 동영상신호의 실시간 처리에 많은 문제를 갖고 있다. 이를 해결하기 위한 방법이 일부 연구되고 있으나, 이 방법도 실제 적용하기에는 무리가 따르는 복잡한 구조를 갖거나 적용대상이 H.26I으로 한정되어 있다. 본 논문은 ISO/lEC 의 동영상 부호화 표준인 MPEG-1/2를 대상으로 하는 새로운 화면분할 방법을 제안한다. 새롭게 제안한 MPEG화면분할 방법은 완전 압축영역에서 처리를 수행하며 이에 따르는 처리지연이 거의 수반되지 않으므로 실시간 다지점 멀티미디어통신 등에 응용이 가능한 효율적인 방법이다. 또한 이 방법은 MPEG 비트 스트림의 단순 해석 및 조작으로 구현이 가능하며, 압축영역의 분할방법을 사용함으로 화질의 열화를 수반하지 않는다. 제안한 방법에 대한 소프트웨어 시뮬레이션을 통하여 기능의 검증을 완료하였으며, 기존의 방법과 구성의 용이성, 처리에 따르는 지연 그리고 분할처리된 화면의 화질 비교를 통해 제안힌 방법의 효용성을 입증하였다.

• Journal of Community Nutrition
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• 제1권2호
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• pp.75-80
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• 1999

Special nutritional foods are one category of processed foods. In this category, 5 different food standards are defined in the current rule of the Korean Food Code ; that is, infant formulae, complementary foods for infants and young children, foods nutrient supplementation, processed dietary fiber-based foods, and foods for special dietary uses. The major differences between the special dietary uses. The major difference between the special nutritional foods and the other processed foods is that the special nutritional foods are characterized by their dietary uses for specific population groups rather than food ingredients or manufacturing and processing techniques which characterize and distinguish most of other processed foods. Although several countries establish similar standards for this type of foods, they use different legal names such as foods for special dietary uses(U.S.A., CODEX, Japan), foodstuffs intended for particular nutritional uses(EC), or special purpose foods(Australia). In addition, there are some other differences in the definitions for these food types and categorization of food types among countries. The major difference in the definitions is the description of 'special dietary uses' by specifying certain population groups whose nutrient requirements are different from those of ordinary men due to physiological or physical conditions and therefore may not be sufficiently met by consuming ordinary foods. The categorization of this type of foods is based on the type of dietary uses in the other countries, whereas we include foods simply supplemented with nutrients or foods having certain components such as dietary fibers even if these foods types do not have special dietary sues. Recently, a revision of standards for special nutritional food has been proposed. However, the description of 'special dietary uses' is not clearly indicated in the definition, and some food types which should not be categorized into the special nutritional foods still remain in this category. In order to correct these problems, the standard of food labeling in the Food Safety Law needs to be revised along with revision of food standards in the Food Code.

• Earthquakes and Structures
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• 제3권5호
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• pp.719-747
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• 2012

In this paper a novel approach is proposed to address the problem of deriving non-stationary stochastic processes which are compatible in the mean sense with a given (target) response (uniform hazard) spectrum (UHS) as commonly desired in the aseismic structural design regulated by contemporary codes of practice. The appealing feature of the approach is that it is non-iterative and "one-step". This is accomplished by solving a standard over-determined minimization problem in conjunction with appropriate median peak factors. These factors are determined by a plethora of reported new Monte Carlo studies which on their own possess considerable stochastic dynamics merit. In the proposed approach, generation and treatment of samples of the processes individually on a deterministic basis is not required as is the case with the various "two-step" approaches found in the literature addressing the herein considered task. The applicability and usefulness of the approach is demonstrated by furnishing extensive numerical data associated with the elastic design UHS of the current European (EC8) and the Chinese (GB 50011) aseismic code provisions. Purposely, simple and thus attractive from a practical viewpoint, uniformly modulated processes assuming either the Kanai-Tajimi (K-T) or the Clough-Penzien (C-P) spectral form are employed. The Monte Carlo studies yield damping and duration dependent median peak factor spectra, given in a polynomial form, associated with the first passage problem for UHS compatible K-T and C-P uniformly modulated stochastic processes. Hopefully, the herein derived stochastic processes and median peak factor spectra can be used to facilitate the aseismic design of structures regulated by contemporary code provisions in a Monte Carlo simulation-based or stochastic dynamics-based context of analysis.

• 한국토양비료학회지
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• 제50권5호
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• pp.462-471
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• 2017

A more efficient use of nutrients from organic sources can benefit both farmers and water quality in agriculture. In this paper we reviewed information related to the regulations and guidelines of a swine liquid fertilizer to propose an establishment scheme for the official standards of swine manure slurry as a liquid fertilizer for organic farming. According to the law of establishment and designation of official standard of fertilizers, the liquid fertilizer made with pig liquid manure belongs to the byproduct fertilizer as of one of organic fertilizer. However, the official standards for byproduct fertilizers including the liquid fertilizer set by the Rural Development Administration (RDA), especially for a liquid swine manure fertilizer, should be revised to meet the goals of laws pursuing the environmentally sound agriculture, especially for organic farming because the terms and relevant standards need additional specific standards alike the standards such as impurities and parameter for declaration in EU. Therefore, it is suggested that official standards for byproduct fertilizers should be revised with respect to nutrient, salt content as of SAR and Na content instead of NaCl. Also we need to develop the maximum limit of heavy metals in soil to which the liquid fertilizer can be applied, as well as application rate depending on EC of the liquid fertilizer.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제7권4호
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• pp.324-335
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• 2001

CALS 및 전자상거래 시스템과 같은 정보보호 기능이 내장된 각종 정보시스템에서 정보의 안전한 저장 및 통신을 위해서는 정보의 암호화가 필수적이다. 또한, 손실된 키의 복구를 포함하여 수많은 암호키들의 안전한 관리가 중요하다. 본 논문에서는 암호화된 정보의 복구를 위한 암호키 복구 시스템의 설계 및 구현 결과를 논한다. 제안한 시스템은 키 캡슐화 방식이며 키복구 시스템의 국제표준에 해당하는 NIST의 RKRP(Requirements for Key Recovery Products)와 국제 공통 평가 기준인 CC 2.0의 스킴을 따르고 있다. 송신자(암호정보 생산자)는 비밀리에 키복구 에이전트 풀로부터 2개 이상의 에이전트를 선정하며 키복구 서비스를 위해 참여하는 키복구 에이전트들을 알 수 없다. 제안한 시스템은 C/Unix버전과 Java/NT버전으로 각각 개발하였다. 제안한 시스템은 암호화된 통신메시지 뿐만 아니라 저장메시지의 복구에 적용할 수 있으며, 전자상거래 서비스 기술 하부구조를 위한 새로운 보안서비스 솔루션으로서 사용될 수 있다.

• Earthquakes and Structures
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• 제3권3_4호
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• pp.581-609
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• 2012

In this paper a novel non-iterative approach is proposed to address the problem of deriving non-stationary stochastic processes which are compatible in the mean sense with a given (target) response (uniform hazard) spectrum (UHS) as commonly desired in the aseismic structural design regulated by contemporary codes of practice. This is accomplished by solving a standard over-determined minimization problem in conjunction with appropriate median peak factors. These factors are determined by a plethora of reported new Monte Carlo studies which on their own possess considerable stochastic dynamics merit. In the proposed approach, generation and treatment of samples of the processes individually on a deterministic basis is not required as is the case with the various approaches found in the literature addressing the herein considered task. The applicability and usefulness of the approach is demonstrated by furnishing extensive numerical data associated with the elastic design UHS of the current European (EC8) and the Chinese (GB 50011) aseismic code provisions. Purposely, simple and thus attractive from a practical viewpoint, uniformly modulated processes assuming either the Kanai-Tajimi (K-T) or the Clough-Penzien (C-P) spectral form are employed. The Monte Carlo studies yield damping and duration dependent median peak factor spectra, given in a polynomial form, associated with the first passage problem for UHS compatible K-T and C-P uniformly modulated stochastic processes. Hopefully, the herein derived stochastic processes and median peak factor spectra can be used to facilitate the aseismic design of structures regulated by contemporary code provisions in a Monte Carlo simulation-based or stochastic dynamics-based context of analysis.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권6호
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• pp.27-35
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• 2021

This study examined the possibility of reutilization of soil reclaimed from contaminated sites after completing remediation. The current status of soil remediation methods in Korea was reviewed and physicochemical properties of soil before and after remediation processes were examined to access the recycling possibility of reclaimed soils based on Recycling Aggregate Quality Standard. The most commonly practiced soil remediation techniques are soil washing, land farming, and thermal desorption. These techniques tend to deteriorate various soil properties including electrical conductivity(EC), organic matter content(OM), available P₂O₅, and cation exchange capacity(CEC). Evaluation of the properties of soil retrieved after each remediation process indicated soil washing may yield the most suitable soil for use as a filling, covering, back-filling, road pavement, and blocking materials, In addition, the soils reclaimed from land farming and thermal desorption have potential utility as a filling, covering and road pavement materials.

• Steel and Composite Structures
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• 제31권6호
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• pp.559-573
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• 2019

Spiral spacing effect on axial compressive behavior of reinforced concrete filled steel tube (RCFST) stub column is experimentally investigated in this paper. A total of twenty specimens including sixteen square RCFST columns and four benchmarked conventional square concrete filled steel tube (CFST) columns are fabricated and tested. Test variables include spiral spacing (spiral ratio) and concrete strength. The failure modes, load versus displacement curves, compressive rigidity, axial compressive strength, and ductility of the specimens are obtained and analyzed. Especially, the effect of spiral spacing on axial compressive strength and ductility is investigated and discussed in detail. Test results show that heavily arranged spirals considerably increase the ultimate compressive strength but lightly arranged spirals have no obvious effect on the ultimate strength. In practical design, the effect of spirals on RCFST column strength should be considered only when spirals are heavily arranged. Spiral spacing has a considerable effect on increasing the post-peak ductility of RCFST columns. Decreasing of the spiral spacing considerably increases the post-peak ductility of the RCFSTs. When the concrete strength increases, ultimate strength increases but the ductility decreases, due to the brittleness of the higher strength concrete. Arranging spirals, even with a rather small amount of spirals, is an economical and easy solution for improving the ductility of RCFST columns with high-strength concrete. Ultimate compressive strengths of the columns are calculated according to the codes EC4 (2004), GB 50936 (2014), AIJ (2008), and ACI 318 (2014). The ultimate strength of RCFST stub columns can be most precisely evaluated using standard GB 50936 (2014) considering the effect of spiral confinement on core concrete.