• Microbiology and Biotechnology Letters
• /
• v.21 no.4
• /
• pp.354-365
• /
• 1993

A novel control method with automatic tuning of PID controller parameters has been developed for efficient regulation of dissolved oxygen concentration in fed-batch fermentations of Escherichia coli. Agitation speed and oxygen partial pressure in the inlet gas stream were chosen to be the manipulated variables. A heuristic reasoning allowed improved tuning decisions from the supervision of control performance indices and it coule obviate the needs for process assumptions or disturbance patterns. The control input consisted of feedback and feedforword parts. The feedback part was determined by PID control and the feedforward part is determined from the feed rate. The proportional gain was updated on-line by a set of heuristics rules based on the supervision of three performance indices. These indices were output error covariance, the average value of output error, and input covariance, which were calculated on-line using a moving window. The integral and derivative time constants were determined from the period of output response. The specific growth rate was maintained at a low level to avoid acetic acid accumulation and thus to achieve a high cell density. The specific growthe rate was estimated from the carbon dioxide evolution rate. In fed-batch fermentation, the simutaneous control of dissolved oxygen concentration (at 0.2; fraction of saturated value) and specific growth rate (at 0.25$hr^{-1}$) was satisfactory for the entire culture period in spite of the changes in the feed rate and the switching of control input.

• Journal of Institute of Control, Robotics and Systems
• /
• v.6 no.2
• /
• pp.207-216
• /
• 2000

This paper introduces an effective system design method to develop a customer oriented product using a design optimization process and to select a set of critical design paramenters,. The process results in the development of a successful product satisfying customer needs and reducing development risk. The proposed scheme adopted a five step QFD(Quality Function Deployment) in order to extract design parameters from customer needs and evaluated their priority using risk factors for extracted design parameters. In this process we determine critical design parameters and allocate them to subsystem designers. Subsequently design engineers develop and test the product based on these parameters. These design parameters capture the characteristics of customer needs in terms of performance cost and schedule in the process of QFD, The subsequent risk management task ensures the minimum risk approach in the presence of design parameter uncertainty. An application of this approach was demonstrated in the development of weld quality monitoring system. Dominant design parameters affect linearity characteristics of weld defect feature vectors. Therefore it simplifies the algorithm for adopting pattern classification of feature vectors and improves the accuracy of recognition rate of weld defect and the real time response of the defect detection in the performance. Additionally the development cost decreases by using DSP board for low speed because of reducing CPU's load adopting algorithm in classifying weld defects. It also reduces the cost by using the single sensor to measure weld defects. Furthermore the synergy effect derived from the critical design parameters improves the detection rate of weld defects by 15% when compared with the implementation using the non-critical design parameters. It also result in 30% saving in development cost./ The overall results are close to 95% customer level showing the effectiveness of the proposed development approach.

• Journal of Engineering Education Research
• /
• v.14 no.2
• /
• pp.13-20
• /
• 2011

This study aimed to seek the ways of improving program outcomes assessment systems for engineering education accreditation of South Korea through performing comparative analysis on those of the United States. Case-study research method was implemented to achieve the research goal. Five university programs, which have been well recognized as good practices in engineering education accreditation in the United States, were selected and analyzed. In addition, those of three universities in South Korea were chosen for comparative analysis, which were reformed by university affiliated Engineering Education Innovative Centers. The analysis results indicated that there were differences in each program's program outcomes, assessment level of program outcomes, evaluation methods on program outcomes achievement, and analysis and improvement records. It was drawn up that the evaluation methods on program outcomes achievement should be paid full attention. For better program outcomes assessment system, however, the followings are in more attention. Firstly, to establish program outcomes reflecting program goal. Secondly, to set up the detailed plans for analysis and quality improvement on program outcomes. Thirdly, to keep continuing efforts on curriculum update.

• The Mathematical Education
• /
• v.49 no.1
• /
• pp.111-118
• /
• 2010

This paper attempts to establish a scoring system for the originality in evaluation of mathematical creativity. The scoring system is composed of three categories; fluency, flexibility and originality. In this paper, we proposed an evaluation method for originality as following based on relative frequency and standard normal distribution. (1) Fluency: It is judged on the basis of the number of correct answers a student made. If several correct answers are given for a single category, then its maximum score is set to 5 points. (2) Flexibility: We examined how many categories the students' responses can be classified into. If at most 15 answers are allowed for each question, the maximum score of flexibility is 15 points. (3) Originality: Originality score is given if a student made some original response that other students did not show. That is, it reflects relative rarity. The originality is measured according to the following steps: Step 1: Analyze the frequency of how many students made an answer to the response type categorized at low level, and calculate the relative frequency p of each category. Step 2: Find the originality point os for each response, that is, os = max{0,z} where z satisfies P(Z > z) = p with standard normal distributed random variable Z. For example, - p is greater than 0.5: 0 point - p is 0.1587: 1 point - p is 0.0228: 2 points - p is 0.0013: 3 points Step 3: Assign the one's originality score to the sum of originality point for each response. Remark. There is no upper limit of originality score.

• Journal of the Korea Computer Industry Society
• /
• v.2 no.4
• /
• pp.443-454
• /
• 2001

Software design patterns are reusable solutions to recurring problems that occur during software development. As programmers gain experience, they recognize the similarity of new problems to problems they have solved before. With even more experience, they recognize that solutions for similar problems follow recurring patterns. In this paper, as one of these reusable design-patterns, the Intermediator pattern for the efficient communication between business component is designed and implemented. Existent business components were way that follow Facade pattern. But Facade pattern is almost like the existing Interface pattern in that the communication of all the object outside the set is done by only one representative object, and this causes the traffic system to be overloaded. Therefore, the Intermediator pattern supplements the traffic overloads by improving the inefficient system of business components' communication through multi-interface, and make all communication behavior between objects done by Intermediator object which controls all actual behavior by way of Intermediator method implementation. Consequently, the Intermediator pattern is designed and implemented in this paper can bring down the level of coupling and raise the cohesion among objects, and refer to many of other object flexibly through several interfaces.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.9
• /
• pp.2032-2037
• /
• 2011

Marker genes are defined as genes in which the expression level characterizes a specific experimental condition. Such genes in which the expression levels differ significantly between different groups are highly informative relevant to the studied phenomenon. In this paper, first the system can detect marker genes that are selected by ranking genes according to statistics after normalizing data with methods that are the most widely used among several normalization methods proposed the while, And it compare and analyze a performance of each of normalization methods with mult-perceptron neural network layer. The Result that apply Multi-Layer perceptron algorithm at Microarray data set including eight of marker gene that are selected using ANOVA method after Lowess normalization represent the highest classification accuracy of 99.32% and the lowest prediction error estimate.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.7
• /
• pp.1701-1707
• /
• 2010

This study is intended for implementing the system environment that can help integrate and retrieve various types of data in real-time by providing semantic interoperability among distributed heterogeneous information systems. The semantic interoperability is made possible by providing a TMDR(Topicmaps Metadata Registry), a set of ontologies. TMDR, which has been made by combining MDR(MetaData Registry) and TopicMaps and storing them in the database, is able to generate distributed query and provide efficient knowledge. MDR is a metadata management technique for distributed data management. TopicMaps is an ontology representation technique that takes into consideration the hierarchy and association for accessing knowledge data. We have created TMDR, a kind of ontology, that is fit for any system and able to detect and resolve semantic conflicts on the level of data and schema. With this system we propose a query-processing technique to integrate and access heterogeneous information sources. Unlike existing retrieval methods this makes possible efficient retrieval and reasoning by providing association focusing on subjects.

• The KIPS Transactions:PartC
• /
• v.8C no.5
• /
• pp.607-614
• /
• 2001

With a remarkable growth and expansion of Internet, the security issues emerged from intrusions and attacks such as computer viruses, denial of services and hackings to destroy information have been considered as serious threats for Internet and the private networks. To protect networks from those attacks, many vendors have developed various security systems such as firewalls, intrusion detection systems, and access control systems. However, managing those systems individually requires too much work and high cost. Thus, in order to manage integrated security management and establish consistent security management for various security products, the policy model of PN-ISMS (Policy Based Integrated Security Management System) has become very important. In this paper, present the hierarchical policy model which explore the refinement of high-level/conceptual policies into a number of more specific policies to form a policy hierarchy. A formal method of policy description was used as the basis of the mode in order to achieve precision and generality. Z-Notation was chosen for this propose. The Z-Notation is mathematical notation for expressing and communicating the specifications of computer programs. Z uses conventional notations of logic and set theory organized into expressions called schemas.

• The KIPS Transactions:PartB
• /
• v.13B no.4 s.107
• /
• pp.401-408
• /
• 2006

In this paper, we propose a new class of segmentation technique for feature extraction based on the statistical and regional classification at each vertical or horizontal line of digital image data. Data is processed and clustered at each line, different from the point or space process. They are designed to segment gray-scale sectional images using a horizontal and vertical line process due to their statistical and property differences, and to extract the feature. The techniques presented here show efficient results in case of the gray level overlap and not having threshold image. Such images are also not easy to be segmented by the global or local threshold methods. Line pixels inform us the sectionable data, and can be set according to cluster quality due to the differences of histogram and statistical data. The total segmentation on line clusters can be obtained by adaptive extension onto the horizontal axis. Each processed region has its own pixel value, resulting in feature extraction. The advantage and effectiveness of the line-cluster approach are both shown theoretically and demonstrated through the region-segmental carotid artery medical image processing.

• The Journal of Korean Physical Therapy
• /
• v.29 no.1
• /
• pp.1-6
• /
• 2017

Purpose: This study aimed to demonstrate reduction in stroke symptoms by analyzing the changes in respiratory function and activities of daily living (ADL) after respiratory muscle strengthening exercise in patients who had a stroke and thereby, propose an efficient exercise method. Methods: Twenty patients with hemiplegic stroke were divided into two groups, with 10 patients in each. The control group (CG) received the traditional exercise therapy, and the experimental group (EG) received the traditional exercise therapy combined with expiratory muscle strengthening training. The training continued for 6 weeks, 5 days a week. Forced vital capacity (FVC) and forced expiratory volume at 1 second (FEV1) were measured with a spirometer, $SpO_2$ was measured with a pulse oximeter, and ADL were assessed by using the modified Barthel index (MBI). A paired t test was applied to compare the differences before and after the intervention, and an independent t test was used to compare the differences between the groups. The level of statistical significance was set as ${\alpha}=0.05$. Results: The changes in the FVC and FEV1 values within the group showed significant differences only in the EG (p<0.01). The between-group difference was statistically significant only for FVC and FEV1 in the EG (p<0.01). The changes in $SpO_2$ and MBI within the group showed significant differences only in the EG and CG (p<0.01). Between-group differences were statistically significant only for $SpO_2$ and MBI in the EG (p<0.05). Conclusion: The interventions with active patient involvement and combined breathing exercises had a positive impact on all the functions investigated in this study.