• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.3
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• pp.87-97
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• 2018

The traffic accident reports that are generated by the Traffic Broadcasting Networks(TBN) are unstructured data. It, however, has the value as some sort of real-time traffic information generated by the viewpoint of the drives and/or pedestrians that were on the roads, the time and spots, not the offender or the victim who caused the traffic accidents. However, the traffic accident reports, which are big data, were not applied to traffic accident analysis and traffic related research commonly. This study adopting text-mining technique was able to provide a clue for utilizing it for the impacts of traffic accidents. Seven years of traffic reports were grasped by this analysis. By analyzing the reports, it was possible to identify the road names, accident spot names, time, and to identify factors that have the greatest influence on other drivers due to traffic accidents. Authors plan to combine unstructured accident data with traffic reports for further study.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.6
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• pp.77-81
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• 2008

In the deeply coupled GPS/INS integrated systems, if the integration filter update period is longer than the period of GPS navigation data, the loss of correlation values occurs due to the bit transition. This problem can be resolved when data wipe off(DWO) is used. However, general DWO methods requires heavy computation or cannot be applied continuously. This paper proposes an effective DWO method using carrier phase discriminator In order to show validity of the proposed method, simulations were carried out. The simulation results show that the data bit is accurately estimated and conform that the loss of correlation values and the error of code phase is small.

• Journal of Internet Computing and Services
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• v.13 no.1
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• pp.75-81
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• 2012

Previous RFID systems exclusively manage the tags and readers for each company in individual manner. Thus, RFID system manager should understand and design specifications such as tag events, data format, and etc, based on individual companies. But it is very difficult to know all statements. To resolve theses problems, there has been conceptual research about policy-based RFID service management model that is not restrained from standards of typical RFID systems, including EPCglobal standard, and ISO/IEC standard. However, previous proposed service management model only aimed event management without including device management. Therefore, in this paper, we propose extended device management policy model for giving shape to the proposed policy-based RFID service management model. If the proposing device management policy model is used for device management, we can integrate control management for heterogeneous middleware, diverse RFID devices, and applications for each company. Moreover, we show that the RFID device management policy is translated and processed as an example using the proposing policy model in real-time RFID system.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.2
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• pp.255-263
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• 2016

Lane Keeping Assistance System (LKAS) is a kind of Advanced Driver Assistance Systems (ADAS) which are developed to automate/ adapt/ enhance vehicle systems for safety and better driving. The main system function of LKAS is to support the driver in keeping the vehicle within the current lane. LKAS acquires information on the position of the vehicle within the lane and, when required, sends commands to actuators to influence the lateral movement of the vehicle. Recently, the vehicles equipped with LKAS are commercially available in a few vehicle-advanced countries and the installation of LKAS increases for safety enhancement. The test procedures for LKAS evaluations are being discussed and developed in the international committees such as ISO (the International Organization for Standardization) and UNECE (United Nations Economic Commission for Europe). In Korea, the evaluations of LKAS for vehicle safety are planned to be introduced in 2016 KNCAP (Korean New Car Assessment Program). Therefore, the test procedures of LKAS suitable for domestic road and traffic conditions, which accommodate international standards, should be developed. In this paper, some bullet points of the test procedures for LKAS are discussed and proposed by extensive researches of previous documents and reports, which are released in public in regard to lateral test procedures including LKAS and Lane Departure Warning System (LDWS). And then, to evaluate the validity of the proposed test procedures, a series of experiments were conducted using commercially available two vehicles equipped with LKAS. Later, it can be helpful to make a draft considering domestic traffic situations for test procedures of LKAS.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.603-606
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• 2004

Automatic test case generation for testing an embedded software is considered. Existing tools for test case generation such as finite state machine or mutant test usually adopt top down approach and depend upon graphical transition and decision table, which makes it difficult to find out where the bugs exist. Also it is hard to describe the special features of embedded systems such as concurrent execution of individual components. Most of embedded systems interacts with the real world, receiving signals through sensors or switches and sending output signals to actuators that somehow manipulate the environment. Embedded software controls the entire system based on the logics such as interpreting the sensor inputs and making the actuators to start or stop their intended operation. This study proposes an automatic test case generation procedure that tests the system starting from the control logics of sensors, switches and actuators and then their concurrent execution controls, and finally the entire system operation. Such a stepwise approach makes it easy to generate test cases to tell where the bugs of embedded software exist.

• The KIPS Transactions:PartA
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• v.13A no.1 s.98
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• pp.71-78
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• 2006

For using XML data in programming languages, there is a data binding method, which generates classes from XML type definitions. However, since existing binding frameworks for this method generate all classes for element definitions, the number of generated classes becomes large and the complexity of the overall application system gets high. In this research, we propose an inline binding method for selecting necessary classes from element definitions. In the proposed method, classes are created only for elements with repetitions and recursions, and they include fields for values of terminal elements. We introduce a generation algorithm for binding classes and the marshaling methods for recovering the omitted paths. We develop IBinder system to validate the proposed method and compare the generated codes with the ones of existing systems. As a result, we carl show that the number of generated classes decrease substantially compared to other systems.

• Journal of KIISE:Databases
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• v.27 no.4
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• pp.549-561
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• 2000

In database management systems(DBMSs), partial rollback is a useful facility that cancels part of the executed operations upon user's requests without a total rollback. Many relational DBMSs(RDBMSs) provide this facility, However, object-orientccd DBMSs (OODBMSs) cannot utilize the previous recovery scl18lne of partial rollback usccd in (RDBMSs) since, unlike RDBMSs, they use a dual buffer consisting of an object buffer and a page buffer. Therefore, a new recovery scheme is required that rolls back the data efficiently in the dual buffer. We propose four partial rollback schemes in OODBMSs that use a dual buffer. We classify the proposed schemes into the single buffer based partial rollback scheme and the dual buffer based partial rollback scheme according to the number of buffers used for partial rollback processing. We further classify them into Uthe page buffer based partial rollback scheme, 2)the object buffccr based partial rollback scheme, 3)the dual buffer based partial rollback scheme using soft log, and 4)the dual buffer based partial rollback scheme using shadows. We evaluate the performance by mathematical analysis and experiments. The results show that the dual buffer based partial rollback scheme using shadows provides the best performance.

• Journal of KIISE
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• v.42 no.3
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• pp.379-389
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• 2015

With the advent of non-volatile memories such as Phase Change Memory (PCM or PRAM) and Magneto Resistive RAM (MRAM), active studies have been carried out on how to replace Dynamic Random-Access Memory (DRAM) with PRAM. In this paper, we study both endurance and performance issues of existing join algorithms that are based on PRAM-based computer systems and have been widely used until now: Block Nested Loop Join, Sort-Merge Join, Grace Hash Join, and Hybrid Hash Join. Our experimental results show that the existing join algorithms need to be redesigned to improve both the endurance and performance of PRAMs. To the best of our knowledge, this is the first research to scientifically study the results of the four join algorithms running on PRAM-based systems. In this work, our main contribution is the modeling and implementation of a PRAM-based simulator for a comparative study of the existing join algorithms.

• Herbal Formula Science
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• v.28 no.4
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• pp.313-325
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• 2020

Objectives : To explore the associated potential pathways and molecular targets of Hwangryunhaedok-tang(HHT) by the approaches of network pharmacology and bioinformatics in traditional chinese medicine(TCM). Methods : Hwangryunhaedok-tang constituent drugs(Coptidis Rhizoma, CR; Scutellariae Radix, SR; Phellodendri Cortex, PC; Gardeniae Fructus, GF) and their processing types were searched from TCM systems pharmacology(TCMSP). The databases of TCMSP, Kyoto Encyclopedia of Genes and Genomes(KEGG), MCODE and STRING were used to gather information. The network of bioactive ingredients and target gene was constructed by Cytoscape software(version 3.8). Results : A total of 94 HHT active compounds(CR, 12; SR, 35; PC, 33; GF, 14, respectively) were found, and HHT were identified by TCMSP. Applications of KEGG and MCODE analysis indicates that total of 6 bioactive ingredients in the top 10% ranking were obtained and 32 diseases of HHT were screened. The molecular pathway analysis revealed that HHT exerts cancer, inflammation and cerebrovascular diseases effects by acting on several signaling pathway. In addition, HHT found that three genes(e.g. SPIN1, TRIM25, and APP) correlate with the aforementioned diseases. Conclusions : This study showed that network pharmacology analysis is useful to elucidate the complex mechanisms of action of HHT.

• Journal of Korean Society of Rural Planning
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• v.22 no.4
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• pp.71-80
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• 2016

Meanwhile, reference evapotranspiration(ET0) is important information for agricultural management including irrigation planning and drought assessment, the database of reference evapotranspiration for future periods was rarely constructed especially at districts unit over the country. The Coupled Model Intercomparison Project Phase 5 (CMIP5) provides several meteorological data such as precipitation, average temperature, humidity, wind speed, and radiation for long-term future period at daily time-scale. This study aimed to build a database for reference evapotranspiration using the climate forecasts at high resolution (the outputs of HadGEM3-RA provided by Korea Meteorological Administration (KMA)). To estimate reference evapotranspiration, we implemented four different models such as FAO Modified Penman, FAO Penman-Monteith, FAO Blaney-Criddle, and Thornthwaite. The suggested database system has an open architecture so that user could add other models into the database. The database contains 5,050 regions' data for each four models and four Representative Concentration Pathways (RCP) climate change scenarios. The developed database system provides selecting features by which the database users could extract specific region and period data.