• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.4
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• pp.184-192
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• 2015

Korea has already entered into an aging society. In recent decades, the health problems for seniors has received considerable interest. We often see the elderly who have been struggled from discomfort or illness of the foot. Those foot related problems mainly cause from the use of improper shoes. Recently, shoe makers sell the shoes for seniors, so called comfort shoes, but the shoes are too expensive for seniors to buy easily. In this paper, we develop cheap insoles for seniors as an alternative of the comfort shoes and suggest the systematic process for the insoles development. This systematic process is as follows: 1) Survey the literature about the market of insole, 2) Investigate the standard size of body and foot for the seniors in Korea, 3) Analyze the customer needs by survey, 4) Study the walking pattern by experiments, and 5) Develop the novel insole for the seniors to relieve the inconveniences related with foot. From the newly developed insoles, the company B gains the sales increasing effect approximately 30% over through the increase in consumer satisfaction and company reputation and secures for intellectual property rights. Using the database from Korea Research Institute of Standards and Science, the reliability of developing technology of the functional insole has been obtained. The seniors are also enable to choose an alternative of comfort shoes for foot health. In the future, the insoles developed from this study have wide applications in the medical, cosmetic fields, and leisure sports fields. Accordingly, it seems to require more systematic studies utilizing Walk Analyzer and Foot Pressure Meter.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.4
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• pp.130-138
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• 1994

Bottom plates of empty hold are subjected to not only water pressure but also bi-axial inplane loads, specially in the alternate full loading full loading condition of bulk carrier. This kind of plate behaviours is very difficult to be explained and to be estimated using common buckling design guide in the initial design stage of hull structure, therefore, some more concrete studies for this plate structure was performed based on the currently developed buckling estimation formula. In this buckling formula, torsional stiffness effects of edge stiffener are included additionally and effects of elastic buckling strength of plate panel are treated as characteristic value problem. Also considering boundary stiffener effects and inplane and lateral loading, evaluation of bottom plate scantling using this formula, calculated results using various classification regulation of buckling strength and results of first report approach are compared each other and useful guides using developed formula for bottom plate scantling design are discussed.

• International Neurourology Journal
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• v.22 no.4
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• pp.275-286
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• 2018

Purpose: OnabotulinumtoxinA (BoNT-A) is a promising therapy for treating neurogenic detrusor overactivity (NDO) in individuals with spinal cord injury (SCI). This systematic review and meta-analysis aimed to carry out an in-depth review and to make an objective estimation of the efficacy and safety of BoNT-A on NDO after SCI. Methods: The PubMed, Embase, and Cochrane databases were searched for all relevant articles published from 2001 to 2016 that referred to NDO, SCI, and BoNT-A or botulinum toxin A. All data were recorded in an Excel spreadsheet by 2 individual reviewers. Review Manager version 5.3 was used to carry out the meta-analysis. Results: This analysis included 17 studies involving 1,455 patients. Compared with placebo and baseline, BoNT-A was effective in increasing maximum cystometric capacity, volume at first involuntary detrusor contraction, cystometric bladder capacity (all P<0.00001), compliance (P=0.001), and the number of patients with complete dryness (P=0.0003), and decreasing detrusor pressure, the number of patients with no involuntary detrusor contractions, the maximum flow rate, the incidence of detrusor overactivity (all P<0.00001), and the number of urinary incontinence episodes (P=0.001). There were no statistically significant differences between doses of 200 U and 300 U or between injections into the detrusor and submucosa. There were no life-threatening adverse events. Conclusions: BoNT-A is effective and safe in treating NDO after SCI. There were no statistically significant differences between doses of 200 U and 300 U or between injecting into the detrusor and submucosa. However, more high-quality randomized controlled trials are still needed.

• International Area Studies Review
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• v.13 no.2
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• pp.66-88
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• 2009

This paper studies optimal discretionary monetary policy in the presence of uncertainty in the housing sector. In particular, we allow two possible regimes regarding the evolution of housing price inflation and the effects of housing price inflation on the aggregate demand. Estimation results with the US data confirm the presence of two distinctive regimes, one 'normal' and the other more akin to the housing price 'bubble' state. The optimal policy is 'asymmetric' in that the optimal responses in the 'normal' regime require the central bank to lean against the wind to inflationary pressure from CPI and housing inflation, while the central bank is recommended to accommodate it in the other regime.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.342-348
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• 2018

The present study examined the various strength and deformation performances of molding materials recycled using film packaging wastes to ascertain the their applicability to secondary products in construction industries. The stress-strain relationships of molding materials were measured under compression, tension, and flexure in accordance with the ASTM procedure. The measured mechanical properties of recycled molding materials were comparable to typical ranges observed in low-density polyethylene and/or high-density polyethylene. However, to stabilize the properties of the molding materials, further management systems are required as follows: 1) evaluation of mechanical properties of materials with respect to various mixing proportions of waste ingredients; 2) estimation of the effect of foreign substance and moisture contents on the mechanical properties; and 3) establishment of comprehensive database including various sources such as manufacture process including applied pressure to produce the molding materials, and collection region and time of wastes.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.4
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• pp.50-61
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• 2022

Snow, rain, fog, and particulate matter interfere with the vehicle driver's vision, which causes a non-secure safety distance and an increase in speed deviation, causing repetitive large-scale traffic accidents. This study developed a road environment sensor capable of measuring 11 types of fog, snow, rain, temperature, humidity, direction of wind, speed of wind, Insolation, atmospheric pressure, fine particles, rainfall, etc. and compared the visibility measured by the infrared signal value of the development sensor. The relationship between the existing fog visibility sensor and the development sensor measurement was derived from data measured at a visibility of 500m or less that directly affects road safety.

• Geomechanics and Engineering
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• v.32 no.6
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• pp.583-600
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• 2023

The resilient modulus (M_R) of various pavement materials plays a significant role in the pavement design by a mechanistic-empirical method. The M_R determination is done by experimental tests that need time and money, along with special experimental tools. The present paper suggested a novel hybridized extreme gradient boosting (XGB) structure for forecasting the M_R of modified base materials subject to wet-dry cycles. The models were created by various combinations of input variables called deep learning. Input variables consist of the number of W-D cycles (WDC), the ratio of free lime to SAF (CSAFR), the ratio of maximum dry density to the optimum moisture content (DMR), confining pressure (σ₃), and deviatoric stress (σ_d). Two XGB structures were produced for the estimation aims, where determinative variables were optimized by particle swarm optimization (PSO) and black widow optimization algorithm (BWOA). According to the results' description and outputs of Taylor diagram, M1 model with the combination of WDC, CSAFR, DMR, σ₃, and σ_d is recognized as the most suitable model, with R² and RMSE values of BWOA-XGB for model M1 equal to 0.9991 and 55.19 MPa, respectively. Interestingly, the lowest value of RMSE for literature was at 116.94 MPa, while this study could gain the extremely lower RMSE owned by BWOA-XGB model at 55.198 MPa. At last, the explanations indicate the BWO algorithm's capability in determining the optimal value of XGB determinative parameters in M_R prediction procedure.

• Journal of the Korean Geotechnical Society
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• v.24 no.1
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• pp.25-35
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• 2008

It has been recognized that the behaviour of unsaturated soil plays an important role in geomechanics. However, up to now, only a few experimental data are available for the technical difficulties related to both volume changes and suction measurements. In this study, the volume changes of unsaturated compacted silty soil were monitored with proximeter during various triaxial compression tests, which gave a realistic estimation in the volume changes of unsaturated soil sample. From the test results, the behaviours of wetting-induced collapses are observed during the drainage/water absorption tests. Under exhausted-drained conditions during shearing, the shear strength increases with an increasing initial suction. On the other hand, the volume changes become small with an increase in the initial suction. And, the volumetric strain during shearing is independent of the confining pressure.

• Journal of the Korean Geotechnical Society
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• v.25 no.12
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• pp.69-85
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• 2009

It is very important to measure reliable dynamic properties of each zone in dam for seismic design. However, the Vs values of core and rock-fill zone are seldom determined by field test. Consequently, seismic design in dam is performed using Vs values assumed or empirically determined. So, it is required that reliable Vs has to be evaluated by in-situ test. In this study, surface wave method, which is nondestructive, was applied to dam to evaluate Vs profiles of core and rock-fill zone in dam. In 6 dams, using SASW and HWAW methods, Vs profiles were evaluated reliably. D/B of Vs profiles of each zone with depth and relationship between confining pressure and Vs profiles of rock-fill zone were constructed including existing results of other dams. The evaluated D/B and proposed relationship were compared with the frequently used empirical method by Sawada and Takahashi.

• Journal of the Korean Geotechnical Society
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• v.24 no.4
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• pp.67-78
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• 2008

In this study, artificial cemented sand made of a few portland cement and Nak-Dong river sand was researched closely to investigate cementing effect quantitatively through unconfined tests and triaxial tests. The peak strength and elastic modulus increased and dilation of cemented sand was restricted by the cementation, but after breakage of the cementation, dilation and negative excess pore water pressure increased. In stress-strain curve, strain-softening behavior appeared in drained condition but strain-hardening behavior was appeared in undrained condition as a result of the increase of effective stress. The test was quantitatively analyzed by multiple regression models, correlating each response variable with input variable. The equations are valid only over the range investigated. Its adjusted coefficient of determination was $0.81{\sim}0.91$, and dry density is important factor for estimating strength of cemented sand.