• International Journal of Highway Engineering
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• v.10 no.2
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• pp.1-13
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• 2008

This study presents a case study of condition evaluation of various asphalt pavement sections to estimate performance lives. The pavement surface conditions including cracking and rutting are first evaluated using a automatic pavement analyzer, ARAN. HPCI(Highway Pavement Condition Index) values are estimated using the pavement surface distress data. It is observed from the pavement distress survey that the major distress type of the sections is top-down cracking. The modulus value of each pavement layer is back-calculated from the defection data obtained from a FWD(Falling Weight Deflectometer) and compared with the laboratory measured dynamic modulus values. Remaining lives of the various pavement sections are estimated based on a mechanistic-empirical approach and AAHTO 1993 design guide. The structural capacities of the all pavement sections based on the two approaches are strong enough to maintain the pavement sections for the rest of design life. Since the major distress type is top-down cracking, the remaining lives of the pavement sections are estimated based on HPCI and existing performance database of highway pavements. To evaluate the causes of premature pavement distress, various material properties, such as air void, asphalt binder content, aggregate gradation, dynamic modulus and fatigue resistance, are measured from the field cores. It is impossible to accurately estimate the binder contents of field samples using the ignition method. It is concluded from the laboratory tests that the premature top down cracking is mainly due to insufficient compaction and inadequate aggregate gradation.

• Polymer(Korea)
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• v.27 no.3
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• pp.226-234
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• 2003

Ipriflavone (IP), a non-hormonal isoflavone derivative, has been shown to interfere with bone remodeling by inhibiting bone resorption and stimulating bone formation. IP consistently increased the amount of Ca incorporated into the cell layer by mesenchymal stem cells (MSCs). In this study, we developed the novel IP loaded poly(L-lactide-co-glycolide) (PLGA) scaffolds for the possibility of the application of the tissue engineered bone. IP/PLGA scaffo1ds were prepared by solvent casting/salt leaching method and were characterized by porosimeter, scanning electron microscopy, determination of residual salt amount, differential scanning calorimetry, and X-ray diffractometer, respectively. IP/PLGA scaffolds were implanted into the back of athymic nude mouse to observe the effect of IP on the osteoinduction compared with control PLGA scaffo1ds. Thin sections were cut from paraffin embedded tissues and histological sections were stained H&E, von Kossa, and immunohistochemical staining for Type I collagen and osteocalcin. It can be observed that the porosity was above 91.7% and the pore size was above 101 $\mu\textrm{m}$. Control scaffo1d and IP/PLGA scaffo1ds of 50% IP were implanted on the back of athymic nude mouse to observe the effect of IP on the induction of cells proliferation for 9 weeks. The evidence of calcification, osteoblast, and osteoid from the undifferentiated stem cells in the subcutaneous sites and other soft connective tissue sites having a preponderance of stem cells has been observed. From these results, it seems that IP plays an important role for bone induction in IP/PLCA scaffolds.

• Fashion & Textile Research Journal
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• v.17 no.5
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• pp.800-814
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• 2015

This study develops baseball uniforms for amateur baseball players with excellent appearance and functional movement. This study selected a conventional baseball uniform and developed a new one for amateur baseball players with improved function and appearance based on previous research results. In case of developed baseball uniform materials, this study used polyurethane mixed fabric for the top to improve flexibility. A mesh material was used at the armpit, back, and bottom of the top, side line of pants and pockets to improve breathability. In addition, quilted material was added to the knee to improve durability and protection. For the patterns and design, this study used a gusset under the arm to assist in comfortable movement as well as reduced the length of the top and circumference of the hem to decrease unnecessary parts. For the pants, this study used a waistband gripper to avoid the top riding up, added darts behind the knees to bend comfortably, and added additional fabric inside the hem to prevent dirt. In addition, we reduced the width and length of the pants. Wearing evaluation was divided into appearance evaluation by experts and on-site-wearing test by baseball players. The wearing evaluation results for the developed baseball uniform indicated higher evaluations than a conventional baseball uniform in all sections as well as showed significant differences in all sections. The result of movement adaptability evaluation showed the highest satisfaction for 'the top does not ride up' and 'dirt do not get in'.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.5
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• pp.374-379
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• 2002

A new active muffler system has been developed and its superior performance on both noise reduction and engine torque increase is demonstrated with experiment. Main characteristic of the proposed muffler system is the use of destructive interference by transmission path difference of divided exhaust pipes to reduce major exhaust noise components thereby overcoming problems of other active exhaust noise control methods. The exhaust pipe is divided into two sections and joined again downstream. One divided pipe has a sliding mechanism to vary its length, which is controlled to make half wavelength transmission path difference for the major engine rpm frequency. In this system one divided pipe is used to control major rpm frequency and its Harmonics and another pipe is used to control noise component double the frequency of rpm. An after-market tuning muffler, which has very simple internal structure and minimal back pressure, is also installed to remove remaining wideband noise. To make the system to be small enough to be practical, conventional muffler is also installed and used in low rpm range and active muffler is only employed in high rpm range. Noise reduction of the proposed system is comparable to conventional passive muffler. The engine dynamo test has proved the proposed system can recover almost all the torque lost by conventional muffler.

• Journal of the Korean Home Economics Association
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• v.19 no.3
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• pp.21-32
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• 1981

Clothing must have the individual beauty and the function that one can do one's body movement freely. therefore, from the human engineering view point, the exact measurement of the human body and the analysis of it's results must be applied to clothing because the arm works most. In this study, the skin surface of arm was investigated by shell made of Alginate of each movement. And by sometic method the rate of expansion and contraction of each section, inter-relation among the bust girth, axillary arm girth and scye girth and between the shoulder length right and the under axilla waist length were calculate4d. With these results, cap height, breadth of a sleeve and arm hole girth of existing sleeve pattern have been compared and analysed. The results are as follows; 1) According to the developmental figures of shell, the whole area change was small but that of shape was remarkable in M 4, 9, 13. The change of the Block 1 was particular. 2) Over arm length was contracted in all movements except M6 and under arm length expanded. The changes of sections a, b, c are large, while those of sections d, e are small. 3) In terms of latitudes, change of fore-arm region was small. The rate of scye girth varied from 14.3% of M13 to-5.6% of M2. The breadth of a sleeve expanded in all movements, and especially the front region expanded more than the back. 4) The relation between the shoulder length right and under axilla waist length, in all occasions, was contracted mutually, and one contracted, the other expanded. Therefore, in clothing construction when we consider the function of the arm it is better to widen the arm hole and the breadth of a sleeve at the same time than no widen the shoulder length by lowering the upper part of the upper side seam line.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.391-400
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• 1998

The aim of this study was to determine the shaping ability of stainless-steel K file (S-S K file), nickel-titanium K file (Ni-Ti K file) and engine driven nickel-titanium file (Quantec file) in resin simulated root canal. Computed tomography was used to evaluate the change of the root canal morphology. Thirty nine resin simulated root canal were divided into four groups (A:12, B:12, C:12, D:3). Resin simulated canals were scanned by computed tomography before instrumentation (1st C-T scan). Canals were instrumented using step back preparation technique with S-S K file in group A and Ni-Ti K file in group B. Group C was prepared with engine driven Ni-Ti file. Group D was uninstrumented to compare the 1st C-T scan images with 2nd C-T scan images of root canal. Instrumented canals were again scanned using computed tomography (2nd C-T scan), and reformated images of the uninstrumented canals were compared with images of the instrumented canals. In the sections of 2mm and 6mm from the apex, Quantec file caused significantly less canal transportation than S-S K file and Ni-Ti K file (p<0.05). Quantec file produced more centered than S-S K file and Ni-Ti K file in the sections of 2mm and 4mm from the apex (p<0.05). There was no significant difference in the removed volume of canals among the each groups (p>0.05). However the removed canal volume from the apex to 5mm were significantly higher than them from 5mm to 1mm (p<0.05) in each groups. Under the conditions of this study, preparation with Quantec file was more effective and produce more appropriate canal shapes than S-S K file and Ni-Ti K file.

• Geomechanics and Engineering
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• v.19 no.2
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• pp.153-165
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• 2019

A case study of monitoring and analysis of surface settlement induced by tunneling of Tabriz metro line 2 (TML2) is presented in this paper. The TML2 single tunnel has been excavated using earth pressure balanced TBM with a cutting-wheel diameter of 9.49 m since 2015. Presented measurements of surface settlements, were collected during the construction of western part of the project (between west depot and S02 station) where the tunnel was being excavated in sand and silt, below the water table and at an average axis depth of about 16 m. Settlement readings were back-analyzed using Gaussian formula, both in longitudinal and transversal directions, in order to estimate volume loss and settlement trough width factor. In addition to settlements, face support and tail grouting pressures were monitored, providing a comprehensive description of the EPB performance. Using the gap model, volume loss prediction was carried out. Also, COB empirical method for determination of the face pressure was employed in order to compare with field monitored data. Likewise, FE simulation was used in various sections employing the code Simulia ABAQUS, to investigate the efficiency of numerical modelling for the estimating of the tunneling induced-surface settlements under such a geotechnical condition. In this regard, the main aspects of a mechanized excavation were simulated. For the studied sections, numerical simulation is not capable of reproducing the high values of in-situ-measured surface settlements, applying Mohr-Coulomb constitutive law for soil. Based on results, for the mentioned case study, the range of estimated volume loss mostly varies from 0.2% to 0.7%, having an average value of 0.45%.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.1
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• pp.136-146
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• 2000

Although the urban elevated road is welcomed in modern society to deal with urban traffic problems, its negative influence on both the pedestrian environment and urban landscape has been frequently observed. Furthermore, the space under elevated structures has been ignored, being the lost space. Recently, several efforts have been devoted into bringing back the lostspace. However, any specific design guidelines shown in the street design of Japan and Singapore have not been suggested in Korea, yet. This study proposes a case of the Nengdong-Ro street design where the two-story urban elevated road is being constructed and negative effects of the elevated road are largely expected. One of the purposes of Nengdong-Ro street design proposed in this study is to relieve the negative effect os the two-story elevated road, and to provide a better pedestrian environment in Nengdong-Ro. The other purpose is to suggest general guidelines that can be applied to the similar context as Nengdong-Ro. It is considered that the space under the elevated road generally consist of three sections: 1) main section where the elevated road runs parallel with the ground, 2) landing section where elevated road goes down to the ground, and 3) facility section where facilities such as the platform and the ticketing booth are located. The design guidelines are suggested for each section, because each section has a different situation. Plans, section and elevations and the details of the street furniture are also incorporated to support the design guidelines.

• Journal of the Korean Mathematical Society
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• v.45 no.5
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• pp.1443-1482
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• 2008

In this paper we define a Myller configuration in a Finsler space and use some special configurations to obtain results about Finsler subspaces. Let $F^{n}$ = (M,F) be a Finsler space, with M a real, differentiable manifold of dimension n. Using the pull back bundle $({\pi}^{*}TM,\tilde{\pi},\widetilde{TM})$ of the tangent bundle $(TM,{\pi},M)$ by the mapping $\tilde{\pi}={\pi}/TM$ and the Cartan Finsler connection of a Finsler space, we obtain an orthonormal frame of sections of ${\pi}^{*}TM$ along a regular curve in $\widetilde{TM}$ and a system of invariants, geometrically associated to the Myller configuration. The fundamental equations are written in a very simple form and we prove a fundamental theorem. Important lines in a Finsler subspace are defined like special lines in a Myller configuration, geometrically associated to the subspace: auto parallels, lines of curvature, asymptotes. Torse forming vector fields with respect to the Cartan Finsler connection are characterized by means of the invariants of the Frenet frame of a versor field along a curve, and the new notion of torse forming vector fields in the sense of Myller is introduced. The particular cases of concurrence and parallelism in the sense of Myller are completely studied, for vector fields from the distribution $T^m$ of the Myller configuration and also from the normal distribution $T^p$.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.2 no.2
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• pp.11-18
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• 1979

The purpose of this study is to establish a purchasing cost reduction program for the management practical use. The research method of this study is a bibliographical search of the materials available in the library at Keimyung University and the writer's private study, and the case analysis. The body of this study is divided into three sections. The first section deals with the purchasing management systems in terms of the nature and characters of purchasing management and purchasing cost in total management system. The second section includes purchasing cost reduction program through value analysis technique and the third section covers summary and the following conclusions : 1) Top management should be aware of the important position of purchasing activities from the cost point of view, and they should be aware that a good purchasing cost reduction program could be established through value analysis technique. 2) For such a purchasing cost reduction program to be carried out. effectively the management should support and back up the program. 3) There should be a training program to educate and develop the personnel who can manage and operate the purchasing cost reduction program through valuean analysis technique. 4) And cooperative system should be established in management and operative organization system from the total management systems, view for the effective use of the program.