• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.3
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• pp.373-379
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• 2012

This paper presents a fault location algorithm based on the adaptively estimated value of the local sequence source impedance for faults on a parallel transmission line. This algorithm uses only the local voltage and current signals of a faulted circuit. The remote current signals and the zero-sequence current of the healthy adjacent circuit are calculated by using the current distribution factors together with the local terminal currents of the faulted circuit. The current distribution factors consist of local equivalent source impedance and the others such as fault distance, line impedance and remote equivalent source impedance. It means that the values of the current distribution factors can change according to the operation condition of a power system. Consequently, the accuracy of the fault location algorithm is affected by the two values of equivalent source impedances, one is local source impedance and the other is remote source impedance. Nevertheless, only the local equivalent impedance can be estimated in this paper. A series of test results using EMTP simulation data show the effectiveness of the proposed algorithm. The proposed algorithm is valid for a double-circuit transmission line system where the equivalent source impedance changes continuously.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.5
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• pp.885-890
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• 2009

A fault location algorithm using estimated local source impedance after a fault is proposed in this paper. The method uses after fault data only at the local end. It uses the negative sequence current distribution factor for more accurate estimation. The proposed algorithm can keep up with the variation of the local source impedance. Therefore, the proposed algorithm especially is valid for a transmission line interconnected to a wind farm that the equivalent source impedance changes continuously. The performance of the proposed algorithm was verified under various fault conditions using the Simpowersystem of MATLAB Simulink. The proposed algorithm is largely insensitive to the variation in fault distance and fault resistance. The test results show a very high accurate performance.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.967-976
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• 2021

This study aimed to investigate the mechanism by which service companies transfer their services overseas and create new value while interacting with local characteristics. A narrative analysis method was used in a case study of Ajisen Ramen, a Japanese service company that created a Japanese-style ramen restaurant, which experienced rapid growth in China. This study analyzed the restaurant as global service innovation and constructed a causal mechanism to explain the resulting rapid growth. In the pre-entry stage, the tangible value source core service facilitated its successful overseas transfer. In the post-entry stage, value source core service standardization and value sharing were interrelated and locally accepted factors. Knowledge of the local characteristics influenced the local storefront format that allowed contact with local customers. This local front format made it possible to offer local customers new value. The global service innovation mechanism developed through this study reflects a causal diagram that correlated the theoretical concepts of these events.

• ETRI Journal
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• v.19 no.4
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• pp.402-413
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• 1997

A CMOS device which has an extended heavily-doped amorphous silicon source/drain layer on the field oxide and an amorphous silicon local interconnection (ASLI) layer in the self-aligned source/drain region has been studied. The ASLI layer has some important roles of the local interconnections from the extended source/drain to the bulk source/drain and the path of the dopant diffusion sources to the bulk. The junction depth and the area of the source/drain can be controlled easily by the ASLI layer thickness. The device in this paper not only has very small area of source/drain junctions, but has very shallow junction depths than those of the conventional CMOS device. An operating speed, however, is enhanced significantly compared with the conventional ones, because the junction capacitance of the source/drain is reduced remarkably due to the very small area of source/drain junctions. For a 71-stage unloaded CMOS ring oscillator, 128 ps/gate has been obtained at power supply voltage of 3.3V. Utilizing this proposed structure, a buried channel PMOS device for the deep submicron regime, known to be difficult to implement, can be fabricated easily.

• KIEAE Journal
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• v.14 no.4
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• pp.127-131
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• 2014

The ground source heat pump (GSHP) system is a kind of the temperature differential energy system using relatively stable underground temperature as heat source of space heating and cooling. This system can achieve higher performance of system than it of conventional air source heat pump systems. However, its superiority of the system performance is different according to installation location or local climate, because the system performance depends on the underground condition which is decided by annual average air temperature. In this study, in order to estimate the feasibility of the ground source heat pump system according to the local climate, numerical simulation was conducted using the ground heat transfer model and the surface heat balance model. The case study was conducted in the condition of Seoul, Daejeon, and Busan, In the result, the heat exchange rate of Busan was 34.33 W/m as the largest in heating season and it of Seoul was 40.61 W/m as the largest in cooling.

• Journal of Environmental Impact Assessment
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• v.9 no.1
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• pp.87-98
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• 2000

The costs of solid waste management have continued to increase. Stricter environmental regulations have been applied to waste management units. Future integrated solid waste management should be balanced between source reduction, recycling, energy recovery, and land disposal. To achieve more balanced solid waste management programs, more local governments must adopt diversion and recycling goals and finance to meet those goals. The hierarchy of integrated solid waste management must be enforced in a manner that is flexible enough to allow local governments to implement waste management facilities that match the communities' ability to pay for them. In establishing a hierarchy of integrated solid waste management, local governements have difficulties in implementing source reduction and recycling because of a lack of local control and inability to pay for new facilities. Integrated solid waste management involves selecting compatible options for facilities to manage the collection, recovery of energy and materials(transformation), and disposal of solid wastes efficiently. Waste Collection, transformation, and disposal must support source reduction and recycling activities.

• Journal of Internet Computing and Services
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• v.17 no.3
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• pp.55-66
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• 2016

A local storage of HTML5 is a Web Storage, which is stored permanently on a local computer in the form of files. The contents of the storage can be easily accessed and modified because it is stored as plaintext. Moreover, because the internet browser classifies the local storages of each domain using file names, the malicious attacker can abuse victim's local storage files by changing file names. In the paper, we propose a scheme to maintain the integrity and the confidentiality of the local storage's source domain and source device. The key idea is that the client encrypts the data stored in the local storage with cipher key, which is managed by the web server. On the step of requesting the cipher key, the web server authenticates whether the client is legal source of local storage or not. Finally, we showed that our method can detect an abnormal access to the local storage through experiments according to the proposed method.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.106-112
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• 2011

This study developed preliminary assessment methodology for priority listing of soil and groundwater contamination sources, considering source characteristics, local environments and risk receptors. Source characteristics were evaluated by scoring relative risk of contamination sources. Local environments were evaluated by scoring annual rainfall, hydraulic conductivity of aquifer, and annual groundwater use. Risk receptors were evaluated by scoring local population, direct distance to surface water, direct distance to drinking-water wells. Scores of each parameter were allocated by analysing distribution of parameter values obtained from government databases. Distributed scores of source characteristics local environments: risk receptors were 12 : 12 : 12. The preliminary assessment scored 0 to 36 for each soil and groundwater sources. Inventory of soil and groundwater sources consisted of 7 categories. This study applied the preliminary assessment methodology to Manan-Gu, Anyang City, Korea. The number of car repair and washing facility was the largest in the contamination source inventory. Petroleum storage facilities showed the highest assessment score. The preliminary assessment methodology also indicated that Anyang-Dong was the priority section among Anyang-Dong, Suksu-Dong, Bakdal-Dong. This study is the first trial for relative ranking soil and groundwater contamination sources by considering source and local characteristics. Therefore, further researches and revision of the preliminary assessment methodology need to be pursued for various applications.

• Journal of The Korean Astronomical Society
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• v.56 no.2
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• pp.225-229
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• 2023

We investigated an emerging magnetic loop dynamically formed on the Sun, which has the effective footpoint heating source that may play a key role in heating a solar atmosphere with free magnetic energy in it. It is suggested that the heating source could be related to local compression of a plasma in the emerging loop by means of Lorentz force, which converts the magnetic energy to the internal energy of the plasma that is used to reaccelerate a decelerated downflow along the loop, eventually generating the source when the kinetic energy of the downflow is thermalized. By analyzing very high-cadense data obtained from a magnetohydrodynamic simulation, we demonstrate how the local compression is activated to trigger the generation of the heating source. This reveals a characteristic of the emerging loop that experiences a dynamic loop-loop interaction, which causes the local compression and makes the plasma gain the internal energy converted from the magnetic energy in the atmosphere. What determines the characteristic that could distinguish an illuminated emerging loop from a nonilluminated one is discussed.

• Journal of Korean Society of Archives and Records Management
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• v.23 no.1
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• pp.27-45
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• 2023

A source of records is critical and highly valuable for records management. The compositions and functions of an administrative organization, which is the source of public records, are changing according to its frequent reorganizations. In particular, changes in local governments are frequent, and the possibility of change increases over time. The processing department is responsible for various records management tasks as the source and producer of records; however, its scope of qualifications is unclear. As such, this study aims to clarify these sources of records and suggest ways to improve their management. For the objective, this study selected D regional local government and analyzed the forms and frequency of its administrative organizational changes. In particular, the processing department's modified organizational functions and compositions due to reorganizations were also examined. Through the analysis, problems concerning records sources that could arise from changes in the administrative organization and processing department were identified, and improvement plans for records management were suggested.