• Clean Technology
• /
• v.17 no.4
• /
• pp.363-369
• /
• 2011

To evaluate the feasibility of electrodialysis for ammonia nitrogen removal from wastewater, the effects of operating parameters such as diluate concentration, applied voltage and flow rate on the removal of ammonia nitrogen were experimentally estimated. The removal rate was evaluated by measuring the elapsed time for ammonia nitrogen concentration of diluate to reach 20 mg/L. Limiting current density (LCD) linearly increased with ammonia nitrogen concentration and flow rate. The elapsed time was linearly proportional to initial concentration of diluate. Due to relatively large equivalent ion conductivity and ion mobility of ammonia nitrogen, the removal rate increased consistently with flow rate. Increase in the applied voltage gave positive effect to removal rate. From the operation of the electrodialysis module used in this research, the flow rate of 3.2 L/min and 80~90% of applied voltage for LCD are recommended as the optimum operating condition for the removal from high concentrate ammonia nitrogen solution.

• Plant Journal
• /
• v.10 no.3
• /
• pp.34-38
• /
• 2014

Coal-fired power plants have used oil as fuel for start-up but plasma burner is recently introduced in order to reduce costs. It provides fuel oil-free start-up. But at initial operation of Plasma burner, an increase in unburned carbon remains as still pending issue. Also research and operational standards for this problem are insufficient. In this paper, operating procedure will be proposed through analyzing the impact of unburned carbon in accordance with the Plasma arc current. It is also possible to contribute to the national plant industry by demonstrating economics of Plasma burner in commissioning coal-fired power plants.

• Journal of Chest Surgery
• /
• v.29 no.2
• /
• pp.223-226
• /
• 1996

Pulmonary sequestration and congenital cystic adenomatoid malformation are two infrequent congenital pulmonary diseases and the combination of these two entities is rare. We had experienced a 3 week old male patient with a pulmonary mass, who had been sufyerring from tachypnea and chest wall retraction after birth. The pulmonary mass was suspected as a congenital cystic adenomat id malformation by chest CT. And therefore, we performed urgent operation via standard thoracotomy incision. Upon a thoracotomy, there was an extrapleural mass with anomalous blood supply near the posterior diaphragm and multiple cystic lesions in right lower lobe. The two anomalous arteries arising from the thoracic aorta and one vein draining into the azygos vein were ligated. and then the extrapleural mass was removed and a right lower lobectomy was performed. Final histologic diagnosis was congenital cystic adenomatoid malformation associated with extralobar pulmonary sequestration. The patient was discharged without any problem.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.466-469
• /
• 2013

Cars that are currently available to the operator to ensure convenience and safety for electronics devices now on the market supply is developed. The current car black box of electronics service, parking, is to help when reversing. The black box is necessary at the time of the accident. After-market through a lot of these are advertised. However, these products are known only to the rear or the front of the picture, as well, at the time of driving, the accident and the front left and right lateral images of the boundary of the car can not be confirmed. Electronics devices on the market, but they can not give this problem solving. In this paper, we propose these to the algorithm-around view of the driver's operation of the vehicle after the car sideways, left and right of the room with integrated video Black Box is designed to provide.

• Korean Journal of Cleft Lip And Palate
• /
• v.12 no.1
• /
• pp.21-32
• /
• 2009

Generally, an adult cleft lip or/and palate patient shows some amount of maxillary deficiency due to limitation of bony growth caused by heavy scars resulted from previous operations such as a cheiloplasty and/or a palatoplasty at an early child age. To solve the problem, advancement of the maxilla is usually required during orthognathic surgery. However, severe tensional force resulted from heavy scars on the palate and/or the lip, as well as the bony defect at the cleft area limited sufficient advancement of the maxillary segment and finally caused relapse of the reposed maxilla. Therefore, distraction osteogenesis of the maxilla was introduced for the successful maxillary advancement inthose kinds of patients. As both hard and soft tissues can be simultaneously and gradually extended with this technique, tensional force caused by heavy scars opposed to forward movement of the maxilla can be reduced to an extent not to develop severe relapse of the advanced maxilla. Since distraction osteogenesis of the maxilla was applied as one of standard protocols for the treatment of the patients with severe maxillary hypoplasia dueto cleft lip and/or palate, the devices for the distraction was improved to control the vectors of distraction with better and more stable. We have treated a 23-year-old male cleft patient with a severe maxillary hypoplasia using a newly developed a maxillary distraction device and a RP model for a pre-operative simulation surgery. As a result, we could successfully move the maxilla as we designed pre-operatively and also reduce much of operation time. Therefore, we report of the case to share our experience with colleagues.

• Journal of the Korean Solar Energy Society
• /
• v.31 no.5
• /
• pp.77-84
• /
• 2011

Korea and some other countries located in the northern hemisphere employ the air conditioner for the space cooling in the hot summer season and also some kinds of heaters for the space heating in the cold winter season. Especially in Korea, a great number of air conditioners of about 12,700,000 sets have been used these days. However, they are used for a short operation period of only 58 days a year, which results in the material and economic losses. To solve this problem and employ this system for the emergency shelter, a new conversion unit which could convert the existing air conditioner to a heat pump system for simultaneous heating and cooling was developed in this study, and the thermal performance was tested. The results indicated that the indoor air could be heated from $27^{\circ}C$ to $39^{\circ}C$ by the air conditioner converted to a heat pump system with the ambient temperature variation of $-10^{\circ}C{\sim}10^{\circ}C$, and cooled from $20^{\circ}C$ to $15^{\circ}C$ by the converted system with the ambient temperature variation of $20^{\circ}C{\sim}35^{\circ}C$. And also the heating COP increased from 3.3 to 5.3 in case of the heat exchange of the super cooling(HESC) circuit and from 3.0 to 4.0 in case of the By-pass with the ambient temperature variation of $-10^{\circ}C{\sim}10^{\circ}C$, respectively, whereas the cooling COP decreased from 3.1 to 2.1with the increase of the ambient temperature from $20^{\circ}C$ to $35^{\circ}C$.

• Journal of the Korea Society of Computer and Information
• /
• v.8 no.2
• /
• pp.112-121
• /
• 2003

Information Protection and cryptography technology is developed with if but solved problem of real time processing and secret maintain. Therefore this paper is Proposed new PRN-SEED(Pseudo-Random Number-SEED) for the increasing secret rate and processing rate perform performance analysis with existed other cryptography algorithms. Proposed new PRN-SEED crypto-algorithm increase in the processing rate than existed algorithms use bit and byte mixed operation with RNG(Random Number Generator). PRN-SEED that performs simultaneous operations have higher 1.03 in the processing rate and 2 in the cryptosystem performance than existed cryptosystems. Implementation for PRN-SEED use Synopsys Design Analyser Ver. 1999.10, samsung KG75 library and Synopsys VHDL Debegger. As a simulation result, symmetric cryptosystem DES operate 416Mbps at the 40MHz and Rijndael operate 612Mbps at the 50MHz. PRN-SEED cryptosystem have gate counting 10K and operate 430Mbps at the 40MHz and 630Mbps at the 50MHz.

• Journal of Korean Society of Water and Wastewater
• /
• v.31 no.4
• /
• pp.311-319
• /
• 2017

Scale formation is inevitable problem when seawater is treated by vacuum membrane distillation. The reason is the high concentration of calcium ion($Ca^{2+}$), sulfate ion(${SO_4}^{2-}$) and bicarbonate ion(${HCO_3}^-$). These ions form calcium sulfate($CaSO_4$) and calcium carbonate($CaCO_3$) on the membrane. The scale formed on membrane has to be removed, because the flux can be severely reduced and membrane wetting can be incurred. This study was carried out to investigate scale formation and effectiveness of acid cleaning in vacuum membrane distillation for SWRO brine treatment. It was found that permeate flux gradually declined until volume concentration factor(VCF) reached around 1.55 and membrane wetting started over VCF over 1.6 in the formation of precipitates containing $CaSO_4$ during VMD operation. In contrast, when calcium carbonate formed on membrane, permeate flux was gradually reduced until VCF 3.0. The precipitates containing both $CaSO_4$ and $CaCO_3$ were formed on the membrane surface and in the membrane pore.

• Fire Science and Engineering
• /
• v.17 no.4
• /
• pp.86-91
• /
• 2003

Since the air stream in the room controlled by HVAC system affects on he expected response of conventional detectors which are designed in accordance with normal characteristics of air stream in the fire incident, unexpected operation time delay may occur in fire. In order to solve this problem and to improve sensitivity so that to initiate fire in its early stages for minimizing damage and protecting people, we studied and developed Air Sampling Smoke Detector. The Air Sampling Smoke Detector is a kind of active-type fire detection system. it draws air continuously from the protected area through an air sampling pipe network to the smoke density analyzer. This study presents smoke density analysing technique and air intake balancing technique through an air sampling pipe network. As a result of evaluating, Air Sampling Smoke Detector was much more sensitive than conventional smoke detectors that passively wait for smoke to reach them and was not affected by ambient airflow in the room by means of balanced air intake through the sampling holes.

• Fire Science and Engineering
• /
• v.23 no.5
• /
• pp.181-195
• /
• 2009

Modern constitution obtains its justice by protecting the people's basic legal rights. The constitutional rights can be more than a defensive measure against government power by modern viewpoints. The government has to create an atmosphere which the rights are not violated. The Constitution provides that the government has to make efforts to prevent disaster and protect the people from danger in Clause 34, Art. 6. The government has an obligation to protect the people's basic legal rights of life, health and property from fire damages, and those rights are gathering strength under a socialist state principle as fundamental ideology of modern societies. The present fire inspection system gains a point constitutionally but it still needs to be certified as the most suitable system. This article examines the solution to operate fire inspection system efficiently, given the reality of present system operation. It is necessary to improve the system by integrating the present fire inspection with the self fire inspection. Government needs to re-modification the Fire inspections system for prevent and promote (resolve) the problem which government officer (ex fire fighter) can make a irregularities and corruption as do it oneself.