• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.5
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• pp.44-53
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• 2000

The development of paper machines, increasing machine speeds with new, mostly low basis weight and/or high ash content paper grades, as well as the fact that several trends regarding process items have increased the sensitivity of papermaking. At the same time, papermakers are looking for flexibility in the production line. We can say that with all PMs, the biggest benefits with the lowest capital spending can be achieved by focusing on improved wet end management. In order to manage wet end chemistry on a paper machine, our goal is to control subprocesses through which we can influence the operation of the entire wet end with maximum effect. Key measurements and controls are - white water consistency control which is the most effective way to control retention. - charge demand measurement and control which takes care of concentration of the anionic material entering to PM. - ash measurements and controls which are deeply related to retention and paper quality. This paper presents and concentrates to two of these key controls: retention and charge. The purpose of charge control is to give the process control the tools to react to changes caused by amount of dissolved and colloidal material incoming to wet end system. It is called coagulation or fixing control. Retention control is then taking care of retention aid flow to the process by responding any changes seen in white water consistency. It is called flocculation control. Each of these solutions separately, and even more effectively all together, stabilize the wet end operations and so greatly improve the produced paper quality and machine runnability. Practical results will be presented and they are referring to the latest mill cases. We have developed the first wet end measuring system in the late 1980s and control solutions based on this modern measuring technology were completely updated in 1990s. This paper introduces the principle, operation, and results of our unique wet end analyzers (retention and charge) which are at the level of automation solutions as a part of paper machine quality control. Especially our newest member of the platform, on-line charge analyzer has reached and set new standards to the on-line charge monitoring.

• Journal of Korean Academy of Nursing
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• v.47 no.2
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• pp.222-232
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• 2017

Purpose: This study was done to develop a children's sex education program for the parents of lower elementary grade students and to evaluate its effects on sexual knowledge, gender role attitude, parent efficacy for child's sex education, and marital consistency. Methods: A quasi-experimental with a non-equivalent control group pretest-posttest design was used. The participants were 29 couples (58 parents, experimental group=28, control group=30) from G city. The 5-week (5-session) program was developed based on 'A theory of protection: parents as sex educators' and used the case-based small group learning method. Data were collected during July and August 2015. The characteristics of the program developed in the present study were a theoretical-based, client-centered, multi-method. Results: After the intervention, the experimental group showed a significant improvement in sexual knowledge, gender role attitudes, parent efficacy for child's sex education, and marital consistency, compared to the control group. The effect sizes of the program were .64 (knowledge), .65 (gender role attitudes), and .68 (parent efficacy). Conclusion: The results of this study provided implications for the parents as effective sex educator and the role expansion of school health nurses.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.12a
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• pp.373-377
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• 1999

Role Based Access Control(RBAC) reduces the cost of administering access control policies as well as making the process less error-prone. The administration tool is most important component in the concept of RBAC. The administration tool for the RBAC security system is required the consistency of a relationships between user and role in the RBAC Database. In this paper, we propose formal specification in order to manage user-role and role-role relationships. The proposed formal specification leads to the consistency requirements for the RBAC database which are defined as a set of relationship. This paper can easily derive the implementation of the RBAC administration tool by formal specification of operations.

• International Journal of Control, Automation, and Systems
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• v.6 no.3
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• pp.306-319
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• 2008

Reaching fault tolerance in technological systems requires to detect malfunctions. This paper presents a diagnostic method that is robust with respect to unknown-but-bounded uncertainties of the dynamical model and the measurements. By using models of the faultless and the faulty behaviours, a state-set observer computes polyhedral sets from which the consistency of the models with the interval measurements is determined. The diagnostic result is proven to be complete, i.e., the set of faults obtained by the diagnostic algorithm includes the actual fault. The algorithm is illustrated by an application example.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.4
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• pp.403-411
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• 2001

A criterion for evaluation of burners has changed recently, and the environmental problems are raised as a global issue. Burners with higher thermal efficiency and lower oxygen in the exhaust gas, evaluated better. To comply with environmental regulations, burners must satisfy the $NO_x$ and CO regulation. Consequently. 'good burner' means one whose thermal efficiency is high under the constraint of $NO_x$ and CO consistency. To make existing burner satisfy recent criterion, it is highly recommended to develop a feedback control scheme whose output is the consistency of $NO_x$ and CO. This paper describes the development of a real time flame diagnosis technique that evaluate and diagnose the combustion states, such as consistency of components in exhaust gas, stability of flame in the quantitative sense. In this paper, it was proposed on the flame diagnosis technique of burner using Neuro- Fuzzy algorithm. This study focuses on the relation of the color of the flame and the state of combustion. Neuro- Fuzzy learning algorithm is used in obtaining the fuzzy membership function and rules. Using the constructed inference algorithm, the amount of $NO_x$ and CO of the combustion gas was successfully inferred.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.4
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• pp.587-595
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• 2002

Recent trend changes a criterion for evaluation of humors that environmental problems are raised as a global issue. Burners with higher thermal efficiency and lower oxygen in the exhaust gas, evaluated better. To comply with environmental regulations, burners must satisfy the NO/sub x/ and CO regulation. Consequently, 'good burner'means one whose thermal efficiency is high under the constraint of NO/sub x/ and CO consistency. To make existing burner satisfy recent criterion, it is highly recommended to develop a feedback control scheme whose output is the consistency of NO/sub x/ and CO. This paper describes the development of a real time flame diagnosis technique that evaluate and diagnose the combustion states, such as consistency of components in exhaust gas, stability of flame in the quantitative sense. In this paper, it was proposed on the flame diagnosis technique of burner using Neuro-Fuzzy algorithm. This study focuses on the relation of the color of the flame and the state of combustion. Neuro-Fuzzy loaming algorithm is used in obtaining the fuzzy membership function and rules. Using the constructed inference algorithm, the amount of NO/sub x/ and CO of the combustion gas was successfully inferred.

• Journal of KIISE:Software and Applications
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• v.26 no.8
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• pp.974-987
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• 1999

이동 컴퓨팅 환경에서 자주 접근하는 데이터에 대한 캐싱은 무선 채널의 좁은 대역폭에서 경쟁을 줄일 수 있는 유용한 기술이다. 그러나, 트랜잭션 캐시 일관성을 지원하는 전통적인 클라이언트/서버 전략은 클라이언트와 서버간에 많은 양의 통신을 필요로 하기 때문에 이동 클라이언트/서버 컴퓨팅 환경에서는 적절하지 않다. 본 논문에서는 브로드캐스트-기반 캐시 무효화 정책을 사용하면서 트랜잭션 캐시 일관성을 지원하는 OCC-UTS (Optimistic Concurrency Control with Update TimeStamp) 프로토콜을 제안한다. 접근한 데이터에 대한 일관성 검사 및 완료 프로토콜은 캐시 무효화 과정의 내부 과정으로 완전 분산 형태로 효율적으로 구현되며, 일관성 체크의 대부분이 이동 클라이언트에서 수행된다. 또한, 분석 모델에 기반한 성능 비교를 통해, 본 논문에서 제안하는 OCC-UTS 프로토콜이 다른 경쟁 프로토콜보다 높은 트랜잭션 처리율을 얻으며, 데이터 항목을 자주 접근하면 할수록 지역 캐시를 사용하는 OCC-UTS 프로토콜이 더 효율적임을 보인다. 이동 클라이언트의 접속 단절에 대해서는 무효화 브로드캐스트 윈도우를 크게 하여 접속 단절에 적절히 대처할 수 있다.Abstract In a mobile computing environment, caching of frequently accessed data has been shown to be a useful technique for reducing contention on the narrow bandwidth of the wireless channels. However, the traditional client/server strategies for supporting transactional cache consistency that require extensive communications between a client and a server are not appropriate in a mobile client/server computing environment. In this paper, we propose a new protocol, called OCC-UTS (Optimisitic Concurrency Control with Update TimeStamp), to support transactional cache consistency in a mobile client/server computing environment by utilizing the broadcast-based solutions for the problem of invalidating caches. The consistency check on accessed data and the commitment protocol are implemented in a truly distributed fashion as an integral part of cache invalidation process, with most burden of consistency check being downloaded to mobile clients. Also, our experiments based on an analytical model substantiate the basic idea and study the performance characteristics. Experimental results show that OCC-UTS protocol without local cache outperforms other competitor protocol, and the more frequent a mobile client accesses data items the more efficient OCC-UTS protocol with local cache is. With respect to disconnection, the tolerance to disconnection is improved if the invalidation broadcast window size is extended.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.5B
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• pp.317-323
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• 2005

Broadcast disks are suited for disseminating information to a large number of clients in mobile computing environments. In broadcast disks, the server continuously and repeatedly broadcasts all data items in the database to clients without specific requests. The clients monitor the broadcast channel and retrieve data items as they arrive on the broadcast channel. The broadcast channel then becomes a disk from which clients can retrieve data items. This paper proposes a Timestamp based Concurrency Control (TCC) scheme to preserve the consistency of read-only client transactions, when the values of broadcast data items are updated at the server. Previous schemes tried to reduce transaction aborts by consuming considerable amount of downlink communication from the server to clients for transferring control information. On the other hand, the TCC uses a timestamp field of each data item to describe execution order of server transactions. Clients can allow more transaction executions by checking consistency of their read-only transactions with timestamps of data items. As a result, the TCC can reduce the abort ratio of client transactions with minimal control information to be broadcast from the server.

• Journal of KIISE:Databases
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• v.35 no.3
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• pp.257-271
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• 2008

Wireless broadcast environments has character that a number of mobile client can receive data streaming from central server no matter how they are so many. Because it is asymmetric bandwidth in that uplink and downlink bandwidth are different. This advantage helps wireless broadcast environments is used in many applications. These applications work almost read operation and need control concurrency using transaction unit. Previous concurrency control scheme in single channel is not adapted in multi channel environments because consistency of data are broken when a mobile client tunes in a broadcast cycle in a channel and then move into another channel and listen to different broadcast cycle with already accessed broadcast cycle. In this paper, we propose concurrency control for read-only mobile transactions in multiple wireless broadcast channel. First of all, we adapt index and data dedicated channel and propose LBCPC(Longest Broadcast Cycle Per Channel) as new unit of consistency. In index dedicated channel, it is repeatedly broadcasted data in same BCPC(Broadcast Cycle Per Channel) until LBCPC. And mobile transaction executes validation using control information every LBCPC. As a result, consistency of data is kept and average response time is shorter than one in single channel because waiting time for restart reduces. And as control information is broadcasted more frequently than in single channel, it is guaranteed currency about data accessed by transaction. Finally, according to the simulation result, we verify performance of our scheme in multi channel as comparing average response time with single channel.

• The KIPS Transactions:PartD
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• v.12D no.1 s.97
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• pp.21-30
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• 2005

In mobile computing environments, a mobile host caches the data to use the narrow bandwidth efficiently and improve the response time. A server periodically broadcasts the update data for maintaining the cache consistency of a mobile host. However, a method for maintaining cache consistency using periodic invalidation report has a problem that defers the commit decision of a mobile transaction to guarantee its serializable execution. In this paper, we propose CCM-AD method that guarantees the serializable execution of a mobile transaction even in the case that it is executed using cached data. As CCM-AD method guarantees the serializable execution of mobile transactions by using the intersection between the data broadcast to mobile host and the data updated at server. Then the CCM-AD method can reduce the delay of commitment decision of a mobile transaction. Also our method can reduce the size of invalidation report.