• Journal of Electrical Engineering and Technology
• /
• v.12 no.5
• /
• pp.1963-1969
• /
• 2017

In order to overcome the manufacturing difficulty of the transverse-flux permanent magnet linear motor (TFPMLM) and enhance its performance much better, a novel TFPMLM with E-core and 3 dimension (3D) magnetic structures is proposed in this paper. Firstly, its basic structure and operating principle are presented. Then the equivalent 2D configuration of the TFPMLM is transformed, so that the Schwarz-Christoffel (SC) mapping method can be used to analyze the motor. Furthermore, the air gap flux density distribution is solved by SC mapping method, based on which, the EMF waveform, no-load cogging force waveform and load force waveform are obtained. Finally, the prototyped TLPMLM is manufactured and the results are obtained from the experiment and 3D FEM, respectively, which are used to compare with those from SC mapping method.

• Structural Engineering and Mechanics
• /
• v.75 no.2
• /
• pp.133-144
• /
• 2020

This investigation is to study the effect of gravitational field and diffusion on a microstretch thermoelastic medium heating by a non-Gaussian laser beam. The problem was studied in the context of the dual-phase-lag model. The normal mode analysis is used to solve the problem to obtain the exact expressions for the non-dimensional displacement components, the micro-rotation, the stresses, and the temperature distribution. The effect of time parameter, heat flux parameter and gravity response of three theories of thermoelasticity i.e. dual-phase-lag model (DPL), Lord and Shulman theory (L-S) and coupled theory (CT) on these quantities have been depicted graphically for a particular model.

• The Journal of Society for e-Business Studies
• /
• v.3 no.2
• /
• pp.203-217
• /
• 1998

Supply chain management is defined as "an integrative philosophy to manage the total flow of a distribution channel from the supplier to the ultimate user". There are many differences between traditional systems and supply chain management systems, There are so many advantages applying SCM concept in inventory management field from the viewpoint of information sharing. While each firm try to optimize the inventory individually in traditional systems, SCM focus on optimizing the channel-wide-inventory making effort to reduce the inventory interrelatedly, The more complex your network of suppliers, manufacturers, and distributors, the more you are likely to gain operational efficiencies by attending on inventory management. The inventory stockpiles at the various sites, including both incoming materials and finished products, have complex interrelationships. Efficient and effective management of inventory throughout the supply chain significantly improves the ultimate service provided to the customer. The purpose of this thesis is to develop the integrated inventory management system for the control of channel-wide inventory on the intranet by applying SCM concept.

• 한국전산유체공학회:학술대회논문집
• /
• 2007.04a
• /
• pp.53-57
• /
• 2007

The quality of chaotic mixing in square cavity flow was studied numerically by CFD simulation and particle tracking technique. The chaotic mixing was generated by using time-periodic electro-osmotic flow. Finite Volume Method (FVM) was employed to get the stretching and folding field in cavity domain. With adjusting the initial condition of concentration distribution, the best values of modulation period and Peclet number which gave us good mixing performance was determined precisely. From $Poicar{\acute{e}}section$and Lyapunov exponents for characteristic trajectories we find that mixing performance also depends on modulation period. The higher value of modulation period, the better mixing performance wag achieved in this case. Furthermore, the results for tracking particle trajectories were also compared between using of Bilinear Interpolation and Higher-order scheme. The values of modulation period for obtaining best mixing effect were matched between using FVM and particle tracking techniques.

• Journal of Magnetics
• /
• v.16 no.2
• /
• pp.186-191
• /
• 2011

[ $YBa_2C_3O_{7-x}$ ]films were fabricated on a $SrTiO_3$ (100) substrate using a trimethylaceate propionic acid (TMAP)-based MOD process by controlling the precursor solution viscosity, firing temperature, and by using various coatings. The viscosity of the precursor solution was controlled by the addition of Xylenes. The films were heat treated with different temperatures from 750 to $800^{\circ}C$. c-axis oriented films were obtained. After adding 9 ml of Xylene into the precursor solution, the $T_c$ of the YBCO film, which was coated 2 times and heat treated at $800^{\circ}C$, was 86 K and the measured $J_c$ was above 2.5 MA/$cm^2$ at 77 K in a zero-field.

• Steel and Composite Structures
• /
• v.25 no.2
• /
• pp.177-186
• /
• 2017

In this work, the model of magneto-thermoelasticity based on memory-dependent derivative (MDD) is applied to a one-dimensional thermal shock problem for a functionally graded half-space whose surface is assumed to be traction free and subjected to an arbitrary thermal loading. The $Lam{\acute{e}}^{\prime}s$ modulii are taken as functions of the vertical distance from the surface of thermoelastic perfect conducting medium in the presence of a uniform magnetic field. Laplace transform and the perturbation techniques are used to derive the solution in the Laplace transform domain. A numerical method is employed for the inversion of the Laplace transforms. The effects of the time-delay on the temperature, stress and displacement distribution for different linear forms of Kernel functions are discussed. Numerical results are represented graphically and discussed.

• Journal of Positioning, Navigation, and Timing
• /
• v.13 no.1
• /
• pp.15-23
• /
• 2024

One of the core keywords in the fourth industrial revolution is convergence, and the convergence of the production, distribution, and consumption processes of services is particularly important. The convergence of user services is underway in various industrial fields including mobile communications, healthcare, mobility, artificial intelligence, etc. In order to offer these converged services efficiently, it is necessary to provide accurate user-centric location information, which can be obtained by employing the global navigation satellite system (GNSS). In addition, as we have entered the post-COVID era, the demand for various fields such as a healthcare, customized tourism services, and aviation services based on accurate location information is exploding. In this paper, we present the results of a case study on the current research trends of GNSS used in telemedicine services and AI & IoT fields, and also analyze these results.

• The Journal of the Petrological Society of Korea
• /
• v.19 no.2
• /
• pp.123-139
• /
• 2010

The properties of fracture system in Precambrian Jangbong schist and Mesozoic granites from Seokmo-do, Ganghwa-gun were investigated and analyzed. Most of the fractures measured at outcrops are nearly vertical or steeply dipping. Orientations of fracture sets in terms of frequency order are as follows: Set $1:N2^{\circ}E/77^{\circ}SE$, Set $2:N17^{\circ}E/84^{\circ}NW$, Set $3:N26^{\circ}E/64^{\circ}SE$, Set $4:N86^{\circ}W/82^{\circ}SW$, Set $5:N80^{\circ}W/77^{\circ}NE$, Set $6:N60^{\circ}W/85^{\circ}SW$, Set $7:N73^{\circ}E/87^{\circ}NW$, Set $8:N82^{\circ}W/53^{\circ}NE$, Set $9:N23^{\circ}W/86^{\circ}SW$, Set 10: $N39^{\circ}W/61^{\circ}NE$. Especially, the rose diagram of fracture strikes(N:240) indicates that there are two dorminant directions of N-S~NNE and WNW. These distribution pattern of fractures from Seokmo-do correponds with those of major lineaments from South Korea suggested in previous study. Meanwhile, the scaling properties on the length distribution of fracture populations have been investigated. First, fracture sets from Precambrian Jangbong schist and Mesozoic granites(north and south rock body) has been classified into five groups(group I~V) based on strike and frequency. Then, the distribution chart generalized the individual length-cumulative frequency diagram for above five groups were made. From the related chart, five subpopulations(group I~V) that closely follow a power-law length distribution show a wide range in exponents(-0.79~-1.53). These relative differences in exponent among five groups emphasizes the importance of orientation effect. From the related chart, the diagram of group III occupies an upper region among five groups. Finally, the distribution chart showing the chracteristics of the length frequency distribution for each rock body were made. From the related chart, the diagram of each rock body shows an order of porphyritic biotite granite < hornblende granodiorite < medium-grained biotite granite(south rock body) < medium-grained biotite granite(north rock body) < Precambrian Jangbong schist. From the related chart, the diagram of more older rock body in the formation age tends to occupy an upper region. Especially, the diagram of Precambrian Jangbong schist occupies an upper region compared with the diagrams of Mesozoic granites. These distributional chracteristics suggests that coexistence of new fracture initiation and growing of existing fractures corresponding with stress field acted since the formation of rock body.

• Korean Journal of Environmental Agriculture
• /
• v.29 no.4
• /
• pp.427-433
• /
• 2010

Aquatic invertebrates are the major important fauna to sustain the paddy ecosystem as predators of the lower trophic level and prey for birds in food-web dynamics as well. The nationwide distribution of scavenger beetles (Hydrophilidae) that is the top predator in an aquatic insect in the paddy field was investigated. A total of 15 scavenger beetles were recognized. Enochrus simulans (98.6%) and Laccobius bedeli (87.7%) showed a high frequency of occurrence on a nationwide scale. The majority of scavenger beetles were higher frequency of occurrence in mountainous regions(33.7%) than in open field regions(5.0%). On the other hand, E. uniformis, Coelostoma stultum and Berosus japonicus showed a low occurrence frequency. Hydrochara affinis, Sternolophus rufipes, Amphiops mater, B. elongatulus, B. signaticollis punctipennis, B. lewisius and H. libera showed regional specific distribution aspect. Therefore, these species can be used as biological index to research the biotic changes in paddy ecology according to an agro-environmental changes including climatic change in the future.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2008.10a
• /
• pp.85-92
• /
• 2008

National Oceanographic Research Institute is carrying out an oceanographic survey for the entire sea areas around Korean Peninsula annually starting with the East Sea from 1996 by establishing a national oceanographic basic map survey plan for the sea areas under the jurisdiction of Korea, so this paper used the oceanographic geomagnetism data measured at the southern area of the Yellow Sea using 'Hae Yang 2000' in 1999, aiming at clarifying the cause of geomagnetic abnormality zone during the course of treating and analyzing the geomagnetic data. For treatment of magnetic data, we obtained electromagnetic force values and geomagnetic abnormality values around the investigated sea area through a process of searching and removal of bad data, correction of sensor positions, correction of magnetic field effects around the hull, correction of diurnal variation, normal correction, correction of cross point errors, etc. The electromagnetic force distribution around the investigated sea area was $49000\;{\sim}\;51600\;nT$, which is judged to be within the normal electromagnetic force intensity distribution range around the Yellow Sea. The isodynamic lines are distributed in Northeast-Southwest direction, and electromagnetic force values are increasing toward the northwest. The result of comparing the magnetic abnormality around the sea area among $124^{\circ}$ 49' 48" E, $35^{\circ}$ 10' 48" N $\sim$ $125^{\circ}$ 7' 48" E, and $35^{\circ}$ 33' 00" N sections with the elastic wave cross section and the result of modeling coincide well with the underground geological structure clarified from the existing elastic wave survey cross section. Therefore, it is judged that the distribution of magnetic force abnormality generally shows the effect pursuant to the distribution of the sedimentary basins in the Tertiary period and the bedrocks in the Cretaceous period which are well developed in the bottom of the sea.