• Structural Engineering and Mechanics
• /
• v.59 no.3
• /
• pp.455-473
• /
• 2016

Methods for the seismic demands evaluation of structures require iterative procedures. Many studies dealt with the development of different inelastic spectra with the aim to simplify the evaluation of inelastic deformations and performance of structures. Recently, the concept of inelastic spectra has been adopted in the global scheme of the Performance-Based Seismic Design (PBSD) through Capacity-Spectrum Method (CSM). For instance, the Modal Pushover Analysis (MPA) has been proved to provide accurate results for inelastic buildings to a similar degree of accuracy than the Response Spectrum Analysis (RSA) in estimating peak response for elastic buildings. In this paper, a simplified nonlinear procedure for evaluation of the seismic demand of structures is proposed with its applicability to multi-degree-of-freedom (MDOF) systems. The basic concept is to write the equation of motion of (MDOF) system into series of normal modes based on an inelastic modal decomposition in terms of ductility factor. The accuracy of the proposed procedure is verified against the Nonlinear Time History Analysis (NL-THA) results and Uncoupled Modal Response History Analysis (UMRHA) of a 9-story steel building subjected to El-Centro 1940 (N/S) as a first application. The comparison shows that the new theoretical approach is capable to provide accurate peak response with those obtained when using the NL-THA analysis. After that, a simplified nonlinear spectral analysis is proposed and illustrated by examples in order to describe inelastic response spectra and to relate it to the capacity curve (Pushover curve) by a new parameter of control, called normalized yield strength coefficient (${\eta}$). In the second application, the proposed procedure is verified against the NL-THA analysis results of two buildings for 80 selected real ground motions.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.2
• /
• pp.335-341
• /
• 2017

The complexity of the bacterial recombination system is a barrier for the construction of bacterial mutants for the further functional investigation of specific genes. Several protocols have been developed to inactivate genes from the genus Pseudomonas. Those protocols are complicated and time-consuming and mostly do not enable easy construction of multiple knock-ins/outs. The current study describes a single and double crossover-recombination system using an optimized vector-free allele-exchange protocol for gene disruption and gene replacement in a single species of the family Pseudomonadaceae. The protocol is based on self-ligation (circularization) for the DNA cassette which has been obtained by overlapping polymerase chain reaction (Fusion-PCR), and carries an antibiotic resistance cassette flanked by homologous internal regions of the target locus. To establish the reproducibility of the approach, three different chromosomal genes (ncRNA31, rpoN, rpoS) were knocked-out from the root-associative bacterium Pseudomonas stutzeri A1501. The results showed that the P. stutzeri A1501 mutants, which are free of any plasmid backbone, could be obtained via a single or double crossover recombination. In order to optimize this protocol, three key factors that were found to have great effect on the efficiency of the homologous recombination were further investigated. Moreover, the modified protocol does not require further cloning steps, and it enables the construction of multiple gene knock-in/out mutants sequentially. This work provides a simple and rapid mutagenesis strategy for genome editing in P. stutzeri, which may also be applicable for other gram-negative bacteria.

• Acta Via Serica
• /
• v.2 no.1
• /
• pp.31-47
• /
• 2017

The corridors to the north and south of the $Takl{\bar{a}}m{\bar{a}}k{\bar{a}}n$ (塔克拉瑪干 Ta-ke-la-ma-gan) Desert are the most important regions for cultural confluence on the Silk Road, where caravans made it to the Chinese capital or the Korean Peninsula by the northern road, through the city of Turfan, or the southern path of Khutan. Being an important part of the Silk Road in the course of history, this region was heavily influenced by the cultures of various nations and ethnic communities whose merchants utilized the road to advance their business. The region's language, writing system and literary structure were also affected, so much so that in the course of its tumultuous history, many words, phrases and terms belonging to neighboring cultures found their way into the region, leaving their mark on its linguistic structure. Of the cultural exchanges that took place between the peoples of the region, conspicuous traces can be seen in the architecture, music, literature, texts, and inscriptions. Located in the Turfan region, the minaret of Su Gong (蘇公 Su Gong ) is host to an inscription which bears many signs of such exchanges. As so far no independent research has been conducted to identify the cultural, literary and structural features conveyed in this inscription, the present paper is an attempt to study the inscription in terms of the script, language and syntax in order to unravel the effects of cultures prevalent on the Silk Road on this particular inscription. This study mainly aims to investigate the linguistic structure of the inscription and the impact of the Persian language on Silk Road culture. In fact, we approach the inscription as a symbol of cultural exchange on the Silk Road and will focus on the tradition of Persian inscription-making which affected the Turfan inscription.

• Journal of Information Technology and Architecture
• /
• v.9 no.4
• /
• pp.423-432
• /
• 2012

EA (Enterprise Architecture) is an SI (System Integration) approach, i.e., a comprehensive plan for SI, which shows the elements of SI and the relationships among them. Since EA can be utilized in every stages of SI, the more large-scaled and complicated SI projects are, the more important EA is. Although many central government agencies and wide local governments implemented EA, the current level of EA utilization is still low. One of the reasons is the low level of EA updating. Some reasons of the low level of EA updating are the low frequency of EA updating, and the shortage of workers, as well. In order to improve the frequency of EA updating and alleviate the workloads of SI officers, MLTM (Ministry of land, transport, and maritime affairs) standardized the processes and documents for SI projects, and implemented PMS (Project Management System) that can support the unifying management of SI projects and be connected with EA system. We expect that EA information are updated efficiently, the level of EA utilization is boosted, and the qualities of SI products are improved, by the implementation of the PMS connected with EA system.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.6 no.6
• /
• pp.113-131
• /
• 1998

The objective of the present study is to investigate the characteristics of the dividing flow in the laminar flow region. Using glycerine water solution(wt43%) for Newtonian fluid and the polymer of viscoelastic fluid(500wppm) for non-Newtonian fluid, this research investigates the flow state of the dividing tube in steady laminar flow region of the two dimensional dividing tube by measuring the effect of Reynolds number, dividing angle, and the flow rate ratio on the loss coefficient. In T- and Y-type tubes, the loss coefficients of the Newtonian fluid decreases in constant rate when the Reynolds number is below 100. The effect of the flow rate ratio on the loss coefficients is negligible. But when the Reynolds number is over 100, the loss coefficient with various flow rate ratios approach an asymptotic value. The loss coefficient of the non-Newtonian fluid for different the Reynolds number shows the similar tendency of the Newtonian fluid. And when the Reynolds number is over 300, the loss coefficient is approximately 1.03 regardless of flow rate ratio or the dividing angle. The aspect ratio does hardly influence the reattachment length and the loss coefficient of both Newtonian and non Newtonian fluid. The loss coefficient decreases as the Reynolds number increases. The loss coefficient of Newtonian fluid is larger than that of non-Newtonian fluid.

• Journal of Information Technology and Architecture
• /
• v.9 no.3
• /
• pp.243-251
• /
• 2012

This paper presents the Conceptual Models of the Mission Space-Korea (CMMS-K), which is an ontology-based conceptual modeling framework of the mission space. Through modeling and simulating military trainings, we can reduce the cost of actual military trainings in terms of time, space, and supplies. CMMS-K is being developed to improve the interoperability and reusability of defense models and simulations. CMMS-K reflects the needs and characteristics of Korean military while referring to existing military conceptual modeling frameworks. The main components of CMMS-K contain domain ontologies, a mission space model description language, a mission space modeling tool, and a CMMS-K management system. CMMS-K domain ontologies consist of entity and task ontologies. In this paper, the CMMS-K domain ontologies are described in detail and the feasibility of the proposed method is discussed with a case study.

• Journal of KIISE
• /
• v.43 no.7
• /
• pp.781-785
• /
• 2016

Learning from human behaviors in the real world is essential for human-aware intelligent systems such as smart assistants and autonomous robots. Most of research focuses on correlations between sensory patterns and a label for each activity. However, human activity is a combination of several event contexts and is a narrative story in and of itself. We propose a novel approach of human activity prediction based on event cognition. Egocentric multi-sensor data are collected from an individual's daily life by using a wearable device and smartphone. Event contexts about location, scene and activities are then recognized, and finally the users" daily activities are predicted from a decision rule based on the event contexts. The proposed method has been evaluated on a wearable sensor data collected from the real world over 2 weeks by 2 people. Experimental results showed improved recognition accuracies when using the proposed method comparing to results directly using sensory features.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.02a
• /
• pp.149-149
• /
• 2010

The double-layer antireflection (DLAR) coatings have significant advantages over single-layer antireflection (SLAR) coatings. This is because they will be able to cover a broad range of the solar spectrum which would enhance the overall performance of solar cells. Moreover films deposited at high frequency are expected to show excellent and UV-stable passivation in the refractive index that we adopted. In this work, we present a novel DLAR coating using SiNx:H thin films with refractive indices 1.9 and 2.3 as the top and bottom layers. This approach is cost effective when compared to earlier DLAR coatings with two different materials. SiNx:H films were deposited by Plasma enhanced chemical vapor deposition (PECVD) technique using $SiH_4$, $NH_3$ and $N_2$ gases with flow rates 20~80sccm, 200sccm and 85 sccm respectively. The RF power, plasma frequency and substrate temperature for the deposition were 300W, 13.56 MHz and $450^{\circ}C$, respectively. The optimum thickness and refractive indices values for DLAR coatings were estimated theoretically using Macleod simulation software as 82.24 nm for 1.9 and 68.58 nm for 2.3 respectively. Solar cells were fabricated with SLAR and DLAR coatings of SiNx:H films and compared the cell efficacy. SiNx:H> films deposited at a substrate temperature of $450^{\circ}C$ and that at 300 W power showed best effective minority carrier lifetime around $50.8\;{\mu}s$. Average reflectance values of SLAR coatings with refractive indices 1.9, 2.05 and 2.3 were 10.1%, 9.66% and 9.33% respectively. In contrast, optimized DLAR coating showed a reflectance value as low as 8.98% in the wavelength range 300nm - 1100nm.

• Journal of Welding and Joining
• /
• v.24 no.3
• /
• pp.27-33
• /
• 2006

Structural stress approach is well known as a mesh-size insensitive fatigue assessment method by using finite element analyses. It is, however, difficult to estimate the structural stress (SS) at weld end points due to stress singularities when shell elements are used. In this study, fatigue evaluations with longitudinal load carrying box fillet weldment under out-of-plane bending load have been performed by using virtual node method (VNM) in order to avoid the problem, which is called the weld end effect. Various combinations of virtual node parameters, such as reference point and virtual node locations, are investigated for the estimation of proper structural stress values applying VNM in a systematic manner. The appropriate guidance of virtual node parameter has been offered for the fillet weldment considered in the study. The structural stress values obtained by VNM have also been validated by comparing the result with finite element model including weld bead. Moreover, the fatigue strength of the fillet weldment based on the equivalent structural stress is shown to be consistent with the master S-N curve.

• Advances in environmental research
• /
• v.9 no.2
• /
• pp.97-107
• /
• 2020

The indiscriminate growth in global population poses a threat to the world in handling and disposal of Municipal solid waste. Rapid urban growth increases the production, consumption and generation of Municipal solid waste which leads to a drastic change in the environment. The methane produced from the Municipal Solid waste accounts for up to 11% global anthropogenic emissions, which is a major cause for global warming. This study reports the methane emission estimation using IPCC default, TNO, LandGEM, EPER and close flux chamber from open dump yards at Perungudi and Kodungaiyur in Chennai, India. The result reveals that the methane emission using close flux chamber was in the range of 8.8 Gg/yr-11.3 Gg/yr and 6.1Gg/yr to 9.1 Gg/yr at Kodungaiyur and Perungudi dump yard respectively. The per capita waste generation was estimated based on waste generation and population. The waste generation potential was projected using linear regression model for the period 2017-2050. The trend of CH₄ emission in the actual field measurement were increased every year, similarly the emission trend also increased in IPCC default method (mass balance approach), EPER Germany (zero order decay model) where as TNO and Land GEM (first order decay model) were decreased. The present study reveals that Kodungaiyur dump yard is more vulnerable to methane emission compared to Perungudi dump yard and has more potential in waste to energy conversion mechanisms than compare to Perungudi dump yard.