Modified coagulants were investigated for the removal of phosphorus from secondary effluent of wastewater treatment. The modified coagulants were prepared by mixing alkali earth metal ions such as calcium and magnesium. The basicity of a coagulant influenced on the removal of phosphorus, and coagulants with basicity of 5.9% showed a better removal of total phosphorus than that of 38.5%. Also, coagulants with alkali earth metals enhanced the performance of coagulation by 10% and resulted in 67.1% for total phosphorus removal. Moreover, the removal of suspended solids and chemical oxygen demand was improved using coagulants with low basicity and earth metal ions. Results of this study demonstrated that the use of coagulants with low basicity, and calcium and magnesium ions is recommended to improve wastewater effluent quality.

A membrane module including grid was designed and introduced to MBR (membrane bio-reactor) for the purpose of better control of membrane fouling. It could be anticipated that the grid enhances the shear force of fluid-air mixture into the membrane surface by even-distributing the fluid-air to the membrane module. As MLSS concentration, packing density which is expressed in the ratio of the housing and the cross-sectional area of membrane fibers (Am/At) and air-flow rate were changed, membrane foulings were checked by monitoring fouling resistances. The total fouling resistance (Rc+Rf) without grid installation (i.e., control) was 2.13×1012 m-1 , whereas it was reduced to 1.69×1012 m-1 after the grid was installed. Regardless of the grid installation, the Rc+Rf increased as the packing density increased from 0.09 to 0.28, however, the increment of resistance for the grid installation was less than that of the control. Increase in the air flow rate did not always guarantee the reduction of fouling resistance, indicating that the higher air flow rate can partially de-flocculate the activated sludge flocs, which led to severer membrane fouling. Consequently, installation of grids inside the housing have brought a beneficial effect on membrane fouling and optimum air flow rate is important to keep the membrane lowering fouling.

The purpose of this study is to investigate and compare the change of wind velocity and processing efficiency of sulfuric compounds and more complex odors. The research was conducted in a facility specializing in odor prevention applications using upgraded existing research equipment (from 30 CMM to 200 CMM) on wastewater treatment. The research equipment was installed with the purpose of removing odor from the wastewater treatment (Pasteur Factory) located in Hoengseong-gun, GangWon. To investigate the treatment efficiency of hydrogen sulfide test samples were evaluated with different blower installation positions and changes in wind speed. The wind speed at the static pressure is about 1.70~2.08 times faster than that of the static pressure, although the blower power is different. The efficacy of sulfur compounds and complex odor treatment was 91.27% and 95.20%, respectively. The study results show that it is necessary to review the design point of wind speed due to the increase in facility scale. In addition, considering the characteristics of complex odor, it is necessary to consider additional surcharges. It was determined that the facility plan for odor prevention in relation to wind velocity will be reexamined. Ongoing research will also be considered to help identify any disadvantages and solutions for the ventilator positioning, which is currently installed in the back.

Bloom of small centric diatom Stephanodiscus is quite occasional in winter season in temperate freshwater ecosystems. It often leads to degradation of water quality and affects the quality of supplied drinking water. In a previous study, we have found that naphthoquinone (NQ) 4-6 derivate is an effective tool for efficient mitigation of natural S. hantzschii blooms. In the present research, polylactide (PLA) and agar foam were used as immobilized agent for NQ 4-6 to improve the efficiency of NQ 4-6 compound releasing process for its application under various field conditions. Mesocosm experiments at 10 ton scale suggested that the abundance of S. hantzschii was continuously increased in the control and upon treatment of the mesocosm with immobilized NQ 4-6 from PLA and agar foam. Their algicidal activities were 78.8% and 77.1%, respectively, on S. hantzschii after 10 days. In the mesocosm experiments, the dynamics of biotic (bacteria, HNFs, ciliates, zooplankton) and abiotic (water temperature, dissolved oxygen, pH, conductivity, nutrients) factors remained unaffected. They exhibited similar trends in the control and treatment groups. Therefore, the immobilized NQ 4-6 from PLA and agar foam has potential to be used as an alternative algicidal substance to effectively mitigate natural S. hantzschii blooms under various field conditions. In addition, it not only can be used to control S. hantzschii, but also is an effective technique. The immobilized NQ 4-6 showed stable controlled release in desired system.

OBJECTIVES: This study aims to review a plan to reduce the shoulder width of a deformed round-trip two-lane highway with low traffic volume. METHODS: Installation of a passing lane on a round-trip two-lane (one-way one-lane) highway, and reduction of a shoulder for a round-trip four-lane highway. RESULTS : It is necessary to establish a design criterion for various highways, because the plan to reduce the lane or shoulder width of a highway with low traffic volume was analyzed to have an economic efficiency of 6.8~7.0%. CONCLUSIONS: It is necessary to seek for a plan to establish a national trunk net early by efficiently using the limited financial resources to cope with the traffic demand elastically.

The external R&D, which includes the adoption of the external technology and knowledge in addition to the internal R&D, is one of important factors for the innovation. Especially for small and medium-sized enterprises (SMEs), the external R&D has been considered as a key factor to carry out the innovation more efficiently due to the limitations of their resources and capacities. However, most of extant studies related to external R&D have focused on analyzing the influence of external R&D on innovation outputs or outcomes. Only a few studies have explored the impact of external R&D on the innovation efficiency. This study therefore investigates whether the external R&D effects the industry’s innovation efficiency and productivity. On this study, we used Korean manufacturing industry data of SMEs from 2012 to 2014 and employed a global Malmquist productivity analysis technique, which is based on the Data Envelopment Analysis (DEA), to assess the innovation efficiency and productivity. Innovation performances of external R&D group and internal R&D group are compared. Then, the sectoral patterns of both innovation efficiency and productivity are analyzed with respect to the technological intensity, which is introduced by OECD. The results show that the gap of innovation efficiency between external and internal R&D groups has gradually decreased because of the continuous improvement of the external R&D group’s performance, while the external R&D group lag behind the internal R&D group. In addition, patterns of the innovation efficiency and productivity change were different depending on the technological intensity, which means that the higher the technological intensity, the greater the effect of external R&D.

MTO (Make to Order) is a manufacturing process in which manufacturing starts only after a customer’s order is received. Manufacturing after receiving customer’s orders means to start a pull-type supply chain operation because manufacturing is performed when demand is confirmed, i.e. being pulled by demand (The opposite business model is to manufacture products for stock MTS (Make to Stock), which is push-type production). There are also BTO (Build to Order) and ATO (Assemble To Order) in which assembly starts according to demand. Lean manufacturing by MTO is very efficient system. Nevertheless, the process industry, generally, which has a high fixed cost burden due to large-scale investment is suitable for mass production of small pieces or ‘mass customization’ defined recently. The process industry produces large quantities at one time because of the lack of manufacturing flexibility due to long time for model change or job change, and high loss during line-down (shutdown). As a result, it has a lot of inventory and costs are increased. In order to reduce the cost due to the characteristics of the process industry, which has a high fixed cost per hour, it operates a stock production system in which it is made and sold regardless of the order of the customer. Therefore, in a business environment where the external environment changes greatly, the inventory is not sold and it becomes obsolete. As a result, the company’s costs increase, profits fall, and it make more difficult to survive in the competition.Based on the customer’s order, we have built a new method for order system to meet the characteristics of the process industry by producing it as a high-profitable model. The design elements are designed by deriving the functions to satisfy the Y by collecting the internal and external VOC (voice of customer), and the design elements are verified through the conversion function. And the Y is satisfied through the pilot test verified and supplemented. By operating this make to order system, we have reduced bad inventories, lowered costs, and improved lead time in terms of delivery competitiveness. Make to order system in the process industry is effective for the display glass industry, for example, B and C groups which are non-flagship models, have confirmed that the line is down when there is no order, and A group which is flagship model, have confirmed stock production when there is no order.

본 사례는 공작기계산업의 A사에서 수행한 R&D 개발완료 과제 79건을 대상으로 R&D 효율성을 DEA를 활용하여 분석하고, 그 개선방안을 제시한 것이다. DEA 분석에서투입변수는 R&D 투자비와 연구인력 맨먼스, 산출변수는 개발기간 목표달성률과 예상매출액(5년간)으로 설정하였으며, 표본은 제품, 선행기술, 제어기술로 구분하여 분석하였다. 여기서선행기술은 제품성능을 위한 요소기술과 응용프로그램을 개발하는 것이고 제어기술은 컴퓨터를 토대로 수치제어 프로그램을 설계하는 것이다. 분석결과에 따르면 제품, 제어기술, 선행기술 순으로 효율적으로 운영되고 있어 선행기술의 효율성이 가장 낮았다. 그 이유는 선행기술의 불학실성에 기인한다. 선행기술은 개발목표를 정하기 어렵고 개발계획도 수립하기 어렵다. 심지어 운영하는 과정에도 환경변화가 영향을 미친다. 투자효율성 분석결과에서 CRS는 제품 34.6%, 선행기술 14.3%, 제어기술 38.9%이다. IRS는 제품 53.8%, 선행기술 85.7%, 제어기술 38.9%이다. DRS는 제품 11.5%, 선행기술0%, 제어기술 22.2%이다. 전체적으로 본 사례는 과다투입보다는 과소투입이 문제가 되고 있다. 이는 R&D 투자 부족을 의미한다. 주목할 부분은 기업의 미래 경쟁력이 될 수 있는 응용기술에 대한 과소투입이 심각하다는 것이다. 비효율적 DMU의 효율적 운영을 위해서는 최적의 투입량을 관리해야하며, 이것은 준거집단과의 비교를 통해 구할 수 있다.

The external R&D, which includes the adoption of the external technology and knowledge in addition to the internal R&D, is one of important factors for the innovation. Especially for small and medium-sized enterprises(SMEs), the external R&D has been considered as a key factor to carry out the innovation more efficiently due to the limitations of their resources. However, most studies related to external R&D have focused on innovation outputs or outcomes. Only a few studies have explored the impact of external R&D on the innovation efficiency. This study therefore investigates whether the external R&D effects the industry’s innovation efficiency and productivity. On this study, we used Korean manufacturing industry data of SMEs from 2012 to 2014 and employed a global Malmquist productivity analysis technique, which is based on the Data Envelopment Analysis(DEA), to assess the innovation efficiency and productivity. Then, the sectoral patterns of both innovation efficiency and productivity are analyzed with respect to the technological intensity, which is introduced by OECD. We show that the gap of innovation efficiency between external and internal R&D groups has gradually decreased because of the continuous improvement of the external R&D group’s performance, while the external R&D group lag behind the internal R&D. In addition, patterns of the innovation efficiency and productivity change were different depending on the technological intensity, which means that the higher the technological intensity, the greater the effect of external R&D.

Safety accident in Building construction work in the process of preparation and implementation of the insecure human, material status is often caused by combining the reality is that many things. Accident rate is a similar level in the case of Korea and foreign countries than any country in the measures by the higher fundamental prescription is needed. In this paper, construction safety management of subcontracting work and small construction plan to apply through a survey to reach a sensible alternative. I did In conclusion, the educated workers know well, and so on the work schedule then quickly if safety management personnel in disaster will be able to reduce the rate to a miracle appeared.

본 연구에서는 capacitive deionization(CDI) 공정에 사용되는 셀을 디자인하여 염 제거 성능비교 연구를 수행하였다. 디자인한 셀의 데드존을 알아보기 위하여 computational fluid dynamics(CFD)로 분석하였다. CFD분석은 15, 25, 35ml/min 의 유속에서 진행하였으며, 같은 유속에서의 CDI 결과와 비교하였다. hexagon flow channel 1(HFC1), hexagon flow channel 2(HFC2)의 경우 15ml/min의 유 속에서 88-124%효율을, 25ml/min 에서는 49-50%의 염 제거 효율을 나타내었다. 35ml/min의 유속에서는 HFC1과 HFC2를 foursquare flow channel (FFC)와 비교해보았을 때 차이가 없었다.