The validity of landfill gas models is an important problem considering that they are frequently used for landfill-site-related policy making and energy recovery planning. In this study, the Monte Carlo method was applied to an landfill gas generation model in order to enhance conformity. Results show that the relative mean deviation between measured data and modeled results (MD) decreased from 19.8% to 11.7% after applying the uncertainty range of Intergovernmental Panel on Climate Change (IPCC) to the methane-generation potential and reaction constants. Additionally, when let reaction constant adjust derived errors from all other modeling components, such as model logic, gauging waste, and measured methane data, MD decreased to 6.6% and the disparity in total methane generation quantity to 2.1%.
PURPOSES: The goal of this study is to analyze the operational effects of special roundabouts at large-scale rotaries in Korea. In pursuing the above, this study gives particular attention to comparing standard roundabouts with special roundabouts. METHODS: This study reviews the various types of roundabouts, creates 270 scenarios, builds networks, and comparatively analyzes the operational effects by using VISSIM simulation model and SSAM(Surrogate Safety Assessment Model). RESULTS : First, the operational effects of standard and signalized roundabouts were analyzed, and it was determined that standard roundabouts are the best in the case of under-saturated traffic volume, and signalized roundabouts are the best in the case of over-saturated traffic volume. Second, the operational benefits of a Turbo roundabout were evaluated to be generally lower than the benefits of a standard roundabout, and the benefits of a Turbo roundabout increase when right-turn traffic volume increases. Finally, the safety conflicts of a Turbo roundabout were determined to be the least and decrease when right-turn traffic volume increases. CONCLUSIONS : This study suggests that Turbo roundabouts rank highest for safety, and signalized roundabouts are best for oversaturated traffic volume. This study can be expected to provide some implications for policy decision-making.
This study was carried out in order to evaluate the design suitability of gas scrubbers, which have been operated in Siheung and Ansan Smarthubs, as an odor removal device. Detailed design data of 31 gas scrubbers installed between 2005 to 2014 were investigated. All the scrubbers investigated were found to use a “packed bed” design, and 30 of them used pall rings as packing materials. In determining the bed diameter of scrubbers, many facilities used incorrect packing parameters, which resulted in inappropriate design values for the bed diameter. In determining of the height of packed bed, the height of transfer unit (HTU) was calculated incorrectly because of the misuse of both the constants of packing materials and Schmidt numbers. In addition, the values of number of transfer unit (NTU) were found to be underestimated due to the low removal efficiency goal. Therefore, the adapted values of packed bed height were quite different from the ones calculated in many facilities.
법무부는 정신장애자 범죄가 점진적으로 증가함에 따라 이들을 전문적으로 치료하고 사회적응능력을 향상시키고 이들의 재범을 방지하기 위해 정신질환 수용자들을 위한 정신보건센터를 2012년 이후 4개의 지방교정청관할하에 개원하였다. 이 연구의 목적은 정신질환수용자들이 정신보건센터에서 치료관련 프로그램, 교육프로그램, 훈련프로그램 등 각종 프로그램이 참가자들의 정신관련 치료와 사회적응능력 향상에 도움이 되는지를 알기 위해 각종 프로그램에 대한 분석이 필요하다. 또한 정신보건센터의 운영방식과 교도소 내의 정신보건센터와 지역보건센터와의 연계방안을 고려해야 할 필요성이 있다. 그리고 정신질환자를 위한 보건센터를 더욱 발전시키기 위해서는 외국주요국의 정신질환수형자에 대한 교정처우는 어떠한지를 살펴본 후 우리의 수형자를 위한 정신보건센터의 발전방안을 모색하고자 한다.
With regard to Gung-jung Yeon-hyang(宮中宴享; court banquet), the frequency of banquets that were held at one time beginning Mu-ja J in-jak(戊子進爵; a royal banquet held in 1828) in 1828 (the 28th year of King Sunjo (純祖)'s reign). In proportion to this frequency, there was an increase in the need and importance of Suk-seol-so(熟設所; a kitchen built in temporarily house for court banquet) and Jung-bae-seol-cheong(中排設廳; a temporary place to put offerings) as a space to assist court banquets. Although Suk-seol-so was a temporary but large-scale facility, it was frequently used for long periods. This facility was flexibly established using the variability of Dong-gung(東宮; Palace for Crown Prince) and enhanced the efficiency of censorship and security in conjunction with palace gates and Suk-wi-cheo(宿衛處; guard station, guard room). In addition, it was reused according to the period when the nation and royal family gave finances or banquets. Jung-bae-seol-cheong was established in the place connected to the central space of court banquets and worked as buffer space to resolve the tension on the day of the event. The location where Jung-bae-seol-cheong was established enabled us to confirm the applicability of Bok-do(複道; corridor) connected to Chimjeon(寢殿; royal residence) when holding court banquets. In short, Suk-seol-so and Jung-bae-seol-cheong were auxiliary spaces, but were considered importantly in the palace operation when holding court banquets.
The purpose of this study is to let the entire logistics system be managed in cyberspace by effectively sharing the logistics information between companies involved in the process, changing conventional commerce to electronic commerce. Most of the goods traded through electronic commerce are small goods involving small business transactions. This produces many problems in shipping and delivery and the leads an inefficient logistics system. Another problems is that there is no sharing of information that process the logistics flow and no systematic management of pick-up and delivery information. As a result, rise in logistics cost, longer delivery period and poor service quality are inevitable and these results are becoming an obstacle in the widespread usage of the electronic commerce. Companies that are part of logistics center can cooperate logistics business in Cyber space and share the entire logistics information through the cyber logistics center. This turns out in effective sharing of logistics information, and thus, allows efficient management of logistics, improves logistics service, and reduces logistics cost.
최근 빠른 기술과 시장의 변화에 대응하여, 기업의 생존과 성장을 위한 동태적 역량의 하나로 기업의 양면성 조직 특성에 대한 중요성이 강조되고 있다. 빠른 환경변화에도 불구하고 지속적으로 높은 성과를 보이고 있는 기업은 신제품 기술개발역량 측면에서 기존 제품의 점진적 혁신을 통한 활용적 역량과 함께 새로운 시장 및 기술에 대한 탐험적 역량 둘 모두를 구축하고 균형을 갖는 양면성 조직의 특성을 갖는다.
본 연구는 기술혁신 중소기업이 양면성 조직을 구축 및 운영하는 이유와 방법, 기업의 생 존과 성과에 미치는 영향을 분석하였다. 외부 환경변화에 따른 기업의 내부적 기술혁신전략 과 기업성장단계가 양면성 조직 특성과 성과에 영향을 미친다. 양면성 조직 특성은 구조, 맥 락, 리더십 관점으로 접근하였으며, 연구 분석을 위해 제품의 산업적 특성을 달리하는 3개 중 소기업에 대해 다중사례분석을 수행하였다.
종단적 분석을 통해, 제품의 산업적 특성과 환경 변화에 대응하는 기업의 기술혁신전략 유형에 따라 양면성 조직의 구축 및 운영의 해법이 다르며, 구조, 맥락, 리더십 관점의 양면성 조직 특성이 상호 보완적으로 작용하였다. 또한, 양면성 조직 특성이 중소기업의 생존과 성 과에 중요한 특성임을 확인하였다.
최근 대학의 입시전형의 다양화로 인하여 학생들의 학업 역량과 성취 수준에 편차가 점차 커지고 있기 때문에 대학공부를 수행하는 데 필요한 기초학력의 부족 등으로 인하여 대학공부의 부적응한 사례가 점차 증가하고 있다. 본 연구는 학부생이 겪는 학업 문제를 해결하고 자신이 가진 학업 잠재력을 극대 화하여 성공적인 대학공부 수행할 수 있도록 지원하고자 집단 학습상담 프로그램을 개발하였다. 10명의 학생을 대상으로 시범 프로그램을 운영하고, 사전사후 검사를 실시하여 교육적 성과를 분석하였다. 프 로그램 참여자들은 인지적 정의적 영역에서 상대적으로 향상되는 변화를 도출하였다. 본 연구 결과는 집단 학습상담이 학생들의 학업 편차를 해소하고 자기 주도적 학습자로 자신의 학업 역량을 향상시키 는데 효과적임을 확인하였다.
PURPOSES : Expressways experience chronic and recurring congestion, especially during weekends and holidays, because of the increased demands for leisure-related travel. The alternatives to solve chronic and recurring congestion may be three-fold: (1) physical expansion of expressway capacities, (2) road pricing, and (3) temporal and spatial distribution of traffic demands. Among these, the third alternative may be the most cost-effective method for the Korea Expressway Corporation (KEC) that can be achieved by using the existing ITS infrastructure.
METHODS : KEC initiated a pilot study in which the traffic on congested expressways was managed by providing traffic condition information (i.e., travel times) of neighboring national highways for taking detours via variable message signs (VMS). This study aimed to estimate the detour rate, and the two pilot studies on Seohaean and Yeongdong expressways yielded many benefits.
RESULTS: It was revealed that the total length of congestion segments decreased by 7.8 km, and the average travel speed increased by 5.3 km/h.
CONCLUSIONS: Based on these findings, it was concluded that the propagation of detour information via VMSs during congestion hours can help reduce congestion on expressways and increase the benefits of the entire network.
국내 다수의 정수장이 적용하고 있는 전통적인 정수처리 공정만으로는 신규 유해물질이나 미량유해물질의 처리 보증을 할 수 없다. 안정적인 고도정수처리공정으로 막분리공정의 적용과 연구가 진행되고 있다. 원수의 특성에 따른 막여과 고도정수처리공정의 개발과 이에 대한 장기적인 검증이 필요하다. 본 연구에서는 계절에 따라 고농도의 망간이 발현되고 있는 경북 U정수장 내의 막여과 시설을 운영하면서 고도정수처리공정의 개발과 장기 성능 평가를 진행하였다. 막여과시설의 일처리용량은 1,000 m³으로 최적 운영인자 확보와 정수처리성능을 평가하였다.
MBR 공법의 처리수 중의 총인을 흡착하는 탈인장치를 50m³/일 규모로 운영하였다. 탈인장치는 Ф1m x 2.5mH(2mEH)로 원통형 구조이며, 내부에 모래 및 흡착제가 0.7m³ 및 0.3m³ 충진되었다. MBR 처리수는 탈인장치 하부에서 상부로 이동하면서 총인이 흡착되고, 모래와 흡착제는 중심부의 원형관을 통하여 상부로 이송되고, 재생용액인 ClO2/Ca(OH)2에 의하여 재생된 후 상부로 재 보충된다. MBR 처리수의 총인은 1.0~1.8mg/L였으며, 탈인 장치 처리수 중의 총인은 0.4~0.8mg/L로 나타났다. 흡착제 재생시 발생한 세척수는 약 4% 이내로 운영되었다.
PURPOSES: The aim of this study is to analyze and compare the operational effectiveness and safety of three different types of roundabout found in the literatures using a VISSIM and SSAM program.
METHODS : The three types roundabout tested are the 2-lane roundabout (2R), the Turbo roundabout (TR), and the Flower roundabout (FR). For each scenario, three roundabout types and traffic conditions such as traffic volume and movement ratio were applied to VISSIM in order to compute the average delays. In addition the total conflict was calculated through SSAM by using trajectory data from VISSIM.
RESULTS: From the analysis results, the average delay in TR and FR type was higher than the 2R. Regardless of the roundabout types, the average delay was reduced as the right-turn vehicles increased. The total conflict in TR was fewer than 2R for all traffic conditions.
CONCLUSIONS : The results of this study can be used in the planning and design process of roundabout deployment. The data also provides some numerical justifications in transition from at-grade intersection to roundabout.