• Wind and Structures
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• v.31 no.2
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• pp.103-142
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• 2020

One of the next frontiers in structural wind engineering is the design of tall buildings using performance-based approaches. Currently, tall buildings are being designed using provisions in the building codes and standards to meet an acceptable level of public safety and serviceability. However, recent studies in wind and earthquake engineering have highlighted the conceptual and practical limitations of the code-oriented design methods. Performance-based wind design (PBWD) is the logical extension of the current wind design approaches to overcome these limitations. Towards the development of PBWD, in this paper, we systematically review the advances made in this field, highlight the research gaps, and provide a basis for future research. Initially, the anatomy of the Wind Loading Chain is presented, in which emphasis was given to the early works of Alan G. Davenport. Next, the current state of practice to design tall buildings for wind load is presented, and its limitations are highlighted. Following this, we critically review the state of development of PBWD. Our review on PBWD covers the existing design frameworks and studies conducted on the nonlinear response of structures under wind loads. Thereafter, to provide a basis for future research, the nonlinear response of simple yielding systems under long-duration turbulent wind loads is studied in two phases. The first phase investigates the issue of damage accumulation in conventional structural systems characterized by elastic-plastic, bilinear, pinching, degrading, and deteriorating hysteretic models. The second phase introduces methods to develop new performance objectives for PBWD based on joint peak and residual deformation demands. In this context, the utility of multi-variate demand modeling using copulas and kernel density estimation techniques is presented. This paper also presents joined fragility curves based on the results of incremental dynamic analysis. Subsequently, the efficiency of tuned mass dampers and self-centering systems in controlling the accumulation of damage in wind-excited structural systems are investigated. The role and the need for explicit modeling of uncertainties in PBWD are also discussed with a case study example. Lastly, two unified PBWD frameworks are proposed by adapting and revisiting the Wind Loading Chain. This paper concludes with a summary and a proposal for future research.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1217-1224
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• 2012

Background and Aim: Less than 50% of oral cancer cases are diagnosed at early stages of the disease and this is in part due to poor awareness and lack of knowledge on the signs and symptoms of oral cancer. This study sought to measure the baseline awareness of oral cancer in Malaysia and aimed to increase public awareness and knowledge of oral cancer using a mass media campaign. Methods: Baseline awareness and impact of the campaign was measured using self-administered questionnaires sent via email to individuals. The campaign was aired on two national television channels and the reach was monitored through an independent programme monitoring system. Results: 78.2% of respondents had heard of oral cancer, and this increased significantly after the campaign. However, the ability to recognize signs and symptoms remains unchanged. We found that the level of awareness differed between the distinct ethnic subgroups and the reach of the campaign was not uniform across all ethnicities. Conclusion: This substantial study to measure the oral cancer awareness in Malaysia provides important baseline data for the planning of public health policies. Despite encouraging evidence that a mass media campaign could increase the awareness of oral cancer, further research is required to address the acceptability, comprehensiveness and effectiveness. Furthermore, different campaign approaches may be required for specific ethnic groups in a multi-ethnic country such as Malaysia.

• Economic and Environmental Geology
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• v.39 no.5 s.180
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• pp.525-535
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• 2006

A study on stream-groundwater exchange was performed using head and temperature data of stream water, streambed, and groundwater. Groundwater level and temperature were obtained from multi-depth monitoring wells in small-scale watershed. During the summer and winter season, time series of temperature data at streambed and groundwater were monitored for six months. In the winter time, we measured the temperature gradient between stream water and streambed. The observed data showed three typical types of temperature characteristics. First, the temperature of streambed was lower than that of stream water; second, the temperature of streambed and stream water was similar; and the last, the temperature of streambed was higher than that of stream water. The interconnections between the stream and the streambed were not homogeneously distributed due to weakly developed sediments and heterogeneous bedrock exposed as bed of the stream. The temperature data may be used in formal solutions of the inverse problems to estimate groundwater flow and hydraulic conductivity.

• Economic and Environmental Geology
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• v.40 no.1 s.182
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• pp.29-45
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• 2007

Biogeochemical characteristics involving redox processes in groundwater from a riverine alluvial aquifer was investigated using multi-level monitoring wells (up to 30m in depth). Anaerobic conditions were predominant and high Fe ($14{\sim}37mg/L$) and Mn ($1{\sim}4mg/L$) concentrations were observed at 10 to 20 m in depth. Below 20 m depth, dissolved sulfide was detected. Presumably, these high Fe and Mn concentrations were derived from the reduction of Fe- and Mn-oxides because dissolved oxygen and nitrate were nearly absent and Fe and Mn contents were considerable in the sediments. The depth range of high Mn concentration is wider than that of high Fe concentration. Dissolved organics may be derived from the upper layers. Sulfate reduction is more active than Fe and Mn reduction below 20 m in depth. Disparity of calculated redox potential from the various redox couples indicates that redox states are in disequilibrium condition in groundwater. Carbonate minerals such as siderite and rhodochrosite may control the dissolved concentrations of Fe(II) and Mn(II), and iron sulfide minerals control for Fe(II) where sulfide is detected because these minerals are near saturation from the calculation of solubility equilibria.

• Archives of design research
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• v.17 no.4
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• pp.375-384
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• 2004

The general tendency of approach to Korean Design History has been focusing its primary interest on the grand story in relation to the problems of modernization in political, economical and social aspects of Korea. In the discourse of modernization, however, there are two sides immanent in the modernization: there is the formal, institutional and authoritative modernization developed inside the capitalistic mode of production and the informal, individual and cultural modernization manifested in the mode of everyday lives. Especially, despite the viewpoint of the latter being embossed as an alternative approach in various areas including the academic world of history since the collapse of socialism, the historical recognition of the phenomena of modern design by the Korean design historians is more like the 'history from the above' that exists at the level of the discourse outside the reality rather than the 'history from the below' that exists within the ordinary life. To grant a sense of balance in such frame of historical understanding, it requires the restructuring the design history of Korea through the cultural perspectives from having the representation of mundane lives realized by the voluntary design activity of the common people as research subjects. One of the methods to acquire an answer to such problem is decoding, in the manner of 'cultural history', the life-long domestic artifact made by Madame Yang, Gap Jo (currently 87 years of age) who is a model of typical Korean mother. Through the historical rumination on the traces of unpretentious lives of the people that has been buried under the grand narrative of the Korean Design History, a new era aimed for the historical prospect of Korean design as cultural history will be possible by excavating the petit yet multi-layered meaning of Korean designs.

• Tuberculosis and Respiratory Diseases
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• v.62 no.6
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• pp.549-553
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• 2007

Sarcoidosis is a multi-systemic syndrome of an unknown etiology, and it is characterized by the formation of multiple noncaseating granulomas that disrupt the architecture and function of the tissues in which they reside. The most commonly affected organs are lung, skin and lymph nodes. Overt clinical involvement of the nervous system is uncommon and this occurs in about 5% of all patients during the course of their disease. The most common manifestations are granulomatous leptomeningitis, cranial nerve palsy, electrolyte or other endocrinologic abnormalities, but isolated memory impairment is a rare manifestation. This is a case of 59 years-old male with recent memory impairment, and he was previously diagnosed with pulmonary sarcoidosis by transbronchial lung biopsy. The brain MRI imaging revealed the leptomeningeal and parenchymal involvement of sarcoidosis. He was treated with high dose corticosteroid and his memory function was improved to nearly a normal level. We report here on a case of successful treatment of pulmonary sarcoidosis combined with neurosarcoidosis with using high dose corticosteroid, and the patient presented with recent memory impairment.

• Korean Journal of Child Studies
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• v.37 no.6
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• pp.83-94
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• 2016

Objective: The purpose of this study was to investigate differences in self-leadership and job involvement based on the education levels, majors, and teaching experiences of multicultural family home-visit instructors and the influence of self-leadership on job involvement. Methods: 668 home-visit instructors participated in the online survey from 140 multicultural family support centers in Seoul, 6 metropolitan cities, 9 provinces, and other cities and counties. Data were analyzed through frequency, percentages, Pearson's correlations, one-way ANOVA, $Scheff{\acute{e}}$ post-hoc test, and stepwise multi-regression using SPSS 21.0. Results: The main findings are as follows. First, instructors who were high school graduates had significantly higher scores in self-leadership than the other groups. There was only a significant difference in self-reward of self-leadership based on their majors. There were no significant differences in job involvement based on the education level and major. The greater their home-visit teaching experiences, the higher their scores in self-leadership and job involvement. Second, the stepwise multiple regression model showed that self-expectation, self-goal setting, constructive thinking, and rehearsal of self-leadership explained 49% of the total variance in job involvement. Conclusion: Even though the high school graduates had significantly higher scores in self-expectation, rehearsal, and constructive thinking of self-leadership than the other groups, over-generalization should be avoided because the sample size was relatively small. Based on the finding that greater home-visit teaching experiences was associated with higher self-leadership and job involvement, it would be necessary to improve working condition to prevent instructors from changing jobs. These findings stress the importance of providing opportunities for home-visit instructors to develop leadership, thus improving job involvement.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.517-528
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• 2013

The modular technology has been already applied in automotive industry, plant and shipbuilding industry. Recently, the modular technology was applied in bridge construction. The modular bridge is different from the existing precast bridges in terms of standardized design that the detailed design of members is omitted by using the standard modules; the design of the modular bridge is completed by only assembling the standard modules without design in member level. The girder-type precast modular bridge has been developed as a simply supported bridge. The girder-type precast modular bridge could be applied to the multi-span bridges through the continuity method. The continuity of the girder-type precast modular bridge is achieved by using the link slab which is easy to construction and appropriate to the rapid construction. The link slabs have been used as the type of reinforced concrete structure in US from the 1950's. In 2000's, the link slab using the engineered cementitious concrete (ECC link slab) has been developed. In this study, the RC type link slab which is more reproducible and economic relative to the ECC link slab was used for the continuity of the girder-type precast modular bridges, and the construction detail of RC type link slab was modified. In addition, the modified iterative design method of RC type link slab was proposed in this study. To verify the proposed design method, the flexural tests were conducted using the RC type link slab specimens. Also, the fatigue test using the mock-up specimen was conducted with cyclic loading condition up to two million cycles.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.27-36
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• 2005

This thesis proposed an effective encryption method for the DCT-based image/video contents and made it possible to operate in a high speed by implementing it as an optimized hardware. By considering the increase in the amount of the calculation in the image/video compression, reconstruction and encryption, an partial encryption was performed, in which only the important information (DC and DPCM coefficients) were selected as the data to be encrypted. As the result, the encryption cost decreased when all the original image was encrypted. As the encryption algorithm one of the multi-mode AES, DES, or SEED can be used. The proposed encryption method was implemented in software to be experimented with TM-5 for about 1,000 test images. From the result, it was verified that to induce the original image from the encrypted one is not possible. At that situation, the decrease in compression ratio was only $1.6\%$. The hardware encryption system implemented in Verilog-HDL was synthesized to find the gate-level circuit in the SynopsysTM design compiler with the Hynix $0.25{\mu}m$ CMOS Phantom-cell library. Timing simulation was performed by Verilog-XL from CadenceTM, which resulted in the stable operation in the frequency above 100MHz. Accordingly, the proposed encryption method and the implemented hardware are expected to be effectively used as a good solution for the end-to-end security which is considered as one of the important problems.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.4
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• pp.80-89
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• 2000

In this paper, we propose a new CPLD technology mapping algorithm for sequential circuit under time constraints. The algorithm detects feedbacks of sequential circuit, separate each feedback variables into immediate input variable, and represent combinational part into DAG. Also, among the nodes of the DAG, the nodes that the number of outdegree is more than or equal to 2 is not separated, but replicated from the DAG, and reconstructed to fanout-free-tree. To use this construction method is for reason that area is less consumed than the TEMPLA algorithm to implement circuits, and process time is improved rather than TMCPLD within given time constraint. Using time constraint and delay of device the number of partitionable multi-level is defined, the number of OR terms that the initial costs of each nodes is set to and total costs that the$^1$costs is set to after merging nodes is calculated, and the nodes that the number of OR terms of CLBs that construct CPLD is excessed is partitioned and is reconstructed as subgraphs. The nodes in the partitioned subgraphs is merged through collapsing, and the collapsed equations is performed by bin packing so that it fit to the number of OR terms in the CLBs of a given device. In the results of experiments to MCNC circuits for logic synthesis benchmark, we can shows that proposed technology mapping algorithm reduces the number of CLBs by 15.58% rather than the TEMPLA, and reduces process time rather than the TMCPLD.