• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.22 no.1
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• pp.1-7
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• 2024

In this research, a detailed analysis of the decay heat contributions of both actinides and non-actinides (fission fragments) from spent nuclear fuel (SNF) was made after 50 GWd·tHM^-1 burnup of fresh uranium fuel with 4.5% enrichment lasted for 1,350 days. The calculations were made for a long storage period of 300 years divided into four sections 1, 10, 100, and 300 years so that we could study the decay heat and physical disposal ratios of radioactive waste in medium- and long-term storage periods. Fresh fuel burnup calculations were made using the code MCNP, while isotopic content and then decay heat were calculated using the built-in stiff equation solver in the MATLAB code. It is noted that only around 12 isotopes contribute more than 90% of the decay heat at all times. It is also noted that the contribution of actinides persists and is the dominant ether despite decreasing decay heat, while the effect of fission products decreases at a very rapid rate after about 40 years of storage.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2A
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• pp.157-165
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• 2004

The synchronization algorithm of IEEE 802.11a WLAN(Wireless Local Area Network) has three consecutive processes, which use a short code training symbol, a long code training symbol and a pilot symbol respectively. But in using this synchronization processes, the actual embodiment has two problems. First, the synchronization process has the complex structure using a long code training symbol and a pilot symbol. Second, since the long training symbol is only compensated with the offset correction coefficient, it can not be trusted perfectly. If the equalizer coefficient is obtained in this unstable period, the system performance is degraded. In particular, the system performance becomes worst in case of the 54 Mbps transmission system using the maximum length of data. In this paper, the new algorithm is proposed which can resolve the embodiment complexity of synchronization processes and structural defect, and also it is confirmed by simulation.

• International Journal of High-Rise Buildings
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• v.3 no.1
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• pp.65-71
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• 2014

Baku, the capital of Azerbaijan, has seen a boom in construction in recent years. The old Baku city has been rapidly transforming into a new hub of high-rise buildings and lively cultural centers hosting the Euro Vision Song Contest in 2012 and European Games in 2015. A major population shift to Baku from its suburbs and the countryside has resulted in the doubling of Baku's population in the 4 years between 2009 and 2013. As of January 2013, Baku's population reached four million people, 43% of the citizens in Azerbaijan according to The State Statistical Committee of Azerbaijan. With this trend, the city needs more high-rise buildings to accommodate rapidly increasing demands for more housing and business space. Until the Azerbaijan Seismic Building Code was published in 2010 and became effective, many different seismic criteria, in terms of building codes and seismic intensities, were used for all new high-rise projects in Baku. Some designers used the SNIP (Russian) code with seismic level 9 or level 8 with 1 point penalty. Others used the Turkish code with Seismic Zone 1, UBC 97 with Zone 2 through 4, or IBC with Sa = 0.75 g through 1.0 g. The seismic intensity is now clarified with the Azerbaijan Seismic Building Code. However, the Azerbaijan Seismic Building Code is appropriate for low-rise buildings applications but may be inappropriate for high-rise project applications. This is because the code-defined response spectrum yields unrealistically conservative seismic forces for high-rise buildings with long periods, as compared to those determined by other internationally accepted building codes. This paper provides observations and recommendations for code-based seismic load assessment of high-rise buildings in the Baku area.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.765-772
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• 2008

For RC structures, long-term deformation occurs due to the inherent characteristics, which are creep and shrinkage. In terms of serviceability, it is important to limit deflection caused by the deformation to the allowable deflection. In the recent years, various repair and strengthening methods have been used to improve performance of the existing RC structures. One of the typical methods is FRP externally bonded method (EBR). Fiber reinforced polymer (FRP) has been used worldwide as repair and strengthening materials due to its superior properties. Besides, it has to offer improved strengthening performance not only under instantaneous load but sustained load. Therefore, accurate prediction method of deflection for the RC members externally bonded with FRP under sustained load is required. In this paper, three beams were fabricated. Two beams were externally strengthened with one of CFRP plate and GFRP plate respectively. Total three beams were superimposed under sustained load of 25 kN. During 470 days, deflections at midspan were obtained. Moreover, creep coefficients and shrinkage strains were calculated by using ACI-209 code and CEB-FIP code. In order to predict the deflection of the beams, EMM, AEMM, Branson's method and Mayer's method were used. Through the experiment, it was found that the specimen with CFRP plate has the most flexural capacity and Mayer's method is the most precise method to predict total long-term deflections.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.2
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• pp.149-156
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• 2011

This paper reveals a distance estimation algorithm based on multi-code ultrasonic and wireless sensor network. For measuring the distances among the sensor nodes, each ultrasonic transmitter transmits multi-code ultrasonic signal simultaneously. Receivers use cross correlation method to separate the coded signals. The information of measured distances is broadcasted to each sensor node by wireless sensor network. The wireless sensor network measures the distance among the sensor nodes using the received signal strength of the broadcasting. The multi-code ultrasonic have a limitation of measurable distance. And the received signal strength is affected from an environment. This paper measures a distance using ultrasonic and a received signal strength in short range. These measured data are applied to the least square estimation algorithm. By the expansion of the fitting curve, a distance measurement in long range using the received signal strength is compensated. The coupled system reduce the error to an acceptable level.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.887-890
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• 2009

To transmit information over a channel in the presence of noise, there needs some technique to code the information. One of the coding techniques used for error detection and correction close to the Shannon limit is Low Density Parity Code. LDPC and decoding characteristic features by sum-product algorithm are matched for the performance to Turbo Code, RA(Repeat Accumulate) code, in case of very long code length of LDPC surpass their performance. This paper explains LDPC coding scheme of image data and decoding scheme, implements LDPC decoder in FPGA.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.413-418
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• 1996

The main purpose of this paper is to develop the modified LTC code for accurate analysis of the boron concentration behavior of all components in the Nuclear Steam Supply System (NSSS). This is achieved by adapting a multi-cell mad to the existing Long Term Cooling (LTC) code. To verify the modified LTC, the simulated results were compared with the actual test results measured during YGN 4 initial criticality test. It was shown that the simulated results of this modified LTC were in good agreement with the actual test results. Also, the boron concentration behavior analysis were performed using the modified LTC code for both direct and indirect dilution/boration nude using YGN 3,4 design data. This modified LTC code can provide a valuable information in predicting boron concentration behavior during power maneuvering such as startup operation, shutdown operation and load follow operation. It is expected that the modified LTC can be applied to both on-line and off-line mode using Plant Computer System(PCS).

• Journal of the Korean housing association
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• v.17 no.4
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• pp.37-46
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• 2006

The primary purpose of this study is to provide the managerial guidelines for the comprehensive apartment improvement planning. This plan will consider the time-serial apartment management plan. Through a questionnaire survey, residential satisfactions and demands on apartment units, apartment building and site amenities were investigated. Based on the statistical analysis, residents' demands were assessed. The resident groups were categorized into the three groups considering the apartments' life span where they were living. The results from the statistical analysis were finally compared with the long-term apartment management plan demonstrated in the Housing Code of the Ministry of Construction and Transportation. The major findings of this study were as follows. First, residential satisfaction on the equipments in apartment units was higher than that on the unit plans. Residents' satisfaction on the communal facilities in apartment sites was lower than that on the other factors. Thus, apartment unit plans and communal facilities in sites need to be improved. Second, though we had the three residents' groups, for the results of the residential satisfaction, the groups were divided into two groups: 'less than 10 years group'and 'over than 10 years group'. Considering the residents' demands for the apartment improvement according to the life span of apartment complexes, the habitability factor was demanded by 'the less than 10 years group' and the safety factor by 'the over than 10 years group'. Compared the residents' demands for apartment improvements with the long-term apartment management plan demonstrated in the Housing Code, the improvement cycles demanded by residents were shorter than those in the code. Thus, the management plan in the code should be reconsidered.

• Journal of Ocean Engineering and Technology
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• v.30 no.6
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• pp.451-457
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• 2016

For a carferry with a displacement of 1,633 tonf, a seakeeping analysis-based direct load approach (DLA) was used in Part I of these series, where the final deliverable was the long-term probabilistic acceleration components. In Part II of these series, the tangential acceleration components are explained based on two approaches: a standard called the IMO CSS code and simple formulas with the probable maximum roll and pitch rotations. The subsequent tangential acceleration-induced external force components are also introduced for these two approaches. The lashing strength components were selected from the IMO CSS code. It was assumed that two different vehicles (a car and a truck) were stowed at the most distant locations on the main deck to assume the largest tangential acceleration components and were secured with four steel wires with longitudinal and transverse lashing angles of $45^{\circ}$. Four cases were considered, with different methods for predicting the acceleration components and different tools for the external loads and lashing strengths involved: cases Rule-LS (rule-based maximum probable roll and pitch angles for predicting the acceleration components in conjunction with LashingSafety), DLA-LS (seakeeping-based long-term acceleration components with LashingSafety), CSS-LC (IMO CSS code-based acceleration components using LashCon), and CSS-LS (IMO CSS code-based acceleration components using LashingSafety). In terms of the acceleration and external force components, the CSS-LC and CSS-LS results are more than two times the results of Rule-LS. Thus, when the external forces and lashing strengths are evaluated using CSS-LC and CSS-LS, the truck needs more lashing wires, while Rule-LS and DLA-LS predict that the present lashing configuration is on the safe side.

• Journal of Information Processing Systems
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• v.16 no.4
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• pp.915-934
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• 2020

Software refactoring is a process to restructure an existing software code while keeping its external behavior the same. Currently, various refactoring techniques are being used to develop more readable and less complex codes by improving the non-functional attributes of software. Refactoring can further improve code maintainability by applying various techniques to the source code, which in turn preserves the behavior of code. Refactoring facilitates bug removal and extends the capabilities of the program. In this paper, an exhaustive review is conducted regarding bad smells present in source code, applications of specific refactoring methods to remove that bad smell and its effect on software quality. A total of 68 studies belonging to 32 journals, 31 conferences, and 5 other sources that were published between the years 2001 and 2019 were shortlisted. The studies were analyzed based on of bad smells identified, refactoring techniques used, and their effects on software metrics. We found that "long method", "feature envy", and "data class" bad smells were identified or corrected in the majority of studies. "Feature envy" smell was detected in 36.66% of the total shortlisted studies. Extract class refactoring approach was used in 38.77% of the total studies, followed by the move method and extract method techniques that were used in 34.69% and 30.61% of the total studies, respectively. The effects of refactoring on complexity and coupling metrics of software were also analyzed in the majority of studies, i.e., 29 studies each. Interestingly, the majority of selected studies (41%) used large open source datasets written in Java language instead of proprietary software. At the end, this study provides future guidelines for conducting research in the field of code refactoring.