• The Korean Journal of Pain
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• 제21권3호
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• pp.217-223
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• 2008

Background: Lumbar transforaminal epidural injections (LTEIs) have been utilized in the treatment of radicular pain, and LTEIs have the advantage of target-specificity. However, there have not been enough studies on the contrast patterns in LTEIs with using fluoroscopy. The purpose of this study was to evaluate the spreading epidural contrast patterns that are seen during real-time fluoroscopic guided LTEIs. Methods: A total of 131 patients who underwent fluoroscopic guided LTEIs were studied. The inclusion criteria were those patients with low back pain and/or lower extremity pain that was caused by a herniated nucleus pulposus, lumbar spinal stenosis, failed back surgery syndrome, and herpes zoster-associated pain. We classified the contrast patterns in regard to the contrast flow spreading to the nerve root and/or the unilateral, bilateral or cylinderic type of epidural spreading on the AP view of the fluoroscopy and the ventral or dorsal epidural filling on the lateral view. In addition to the pattern analysis, we evaluated the range of contrast spreading from the cranial to the caudal epidural filling and the incidence of an intravascular flow pattern. Results: Epidural spreading was seen in 126 cases (96.2%) of the total patients through the nerve root. Ventral spreading occurred in 120 cases (95.2%). On the AP view, a nerve root with unilateral, bilateral and cylinderic epidural filling was noted for 108 (85.7%), 9 (7.1%) and 9 (7.1%) cases, respectively. The contrast spreading to vertebral segments was smaller for the patients with lumbar spinal stenosis and failed back surgery syndrome than for the other groups (P < 0.0083). The incidence of intravascular injection was 11.1% (14/126). Conclusions: LTEIs using fluoroscopic visualization provided excellent assessment of the ventral epidural filling as well as nerve root filling. However, unilateral epidural spreading was prominent for the LTEIs.

• 대한소아치과학회지
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• 제23권4호
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• pp.818-839
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• 1996

The strain gage, holographic and photoelastic analysis etc. have been used for stress analysis of prosthesis, orthodontic or orthopedic appliances and filling materials. But these methods has some limitation in analyzing the internal stress. The Finite Element Analysis has been proved to compensate this defect and widely used in this area. The purpose of this study was to compare the stress distributions of the various temporary filling methods being used in pulpotomy procedure. Three different models were designed according to temporary filling material and method: amalgam filling with ZOE base(Model I), amalgam filling with ZPC sub-base and ZOE(Model II), IRM filling only(Model III). The results of the experiment were as follows: 1. In model I under the load case 6 and 1, the significant stress was shown to be concentrated on the buccal portion of crown. 2. Model II showed the similar pattern of stress distribution to Model I. 3. In model III under load case 2, the stress was mainly distributed on the buccal cusp tip and buccal margin of filling material. In same model under the load case 3, the stress was distributed on the lingual cusp tip. 4. Based on the above data, IRM can be assumed to have advantage over the other tested materials in reducing the incidence of crown fracture by localized the stress within the filling materials.

• 한국재료학회지
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• 제9권6호
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• pp.583-588
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• 1999

The characteristics of copper thin films and pattern filling capability were investigated by ECD. Prior to deposition of copper film, seed-Cu/Ta(TaN)/$SIO_2$(BPSG)/Si structure was manufactured. Copper deposition was performed with various current waveforms(DC/PC, 1~10,000Hz) and current densities(10~60 mA/$\textrm{cm}^2$) after pretreatment (Oxident removal, wetting) of seed-layer. Conformal pattern filling was performed using PC method with fast deposition rate of 6,000~8,000$\AA$/min. Heat-treated($450^{\circ}C$, 30min) copper films showed good resistivities of 1.8~2.1$\mu$$\Omega$.cm. According to the XRD analysis, (111)-preferred orientation of copper film was found in ECD-Cu/seed-Cu/Ta/$Sio_2$/Si structure. Also, we have successfully achieved to fill via holes with 0.35$\mu\textrm{m}$ width and 4:1 aspect ratio.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.629-630
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• 2008

• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 추계학술발표강연 및 논문개요집
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• pp.135-135
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• 1998

• 소성∙가공
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• 제19권3호
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• pp.167-172
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• 2010

Roll-to-roll forming process is one of important metal processing technology because the process is simple and economical. These days, with these merits, roll-to-roll forming process is tried to be employed in manufacturing the circuit board, barrier ribs and solar cell plate. However, it is difficult to apply to the forming of micro scale or sub-micro scale pattern. In this study, the roll forming processing for the micro scale is designed and analyzed. The forming of micro pattern for small electric device such as LCD panel by incremental roll forming process is analyzed. Firstly, the optimum analysis conditions are found by several analyses. And then, formability is analyzed for various protrusion shapes at various forming temperatures. The formability is evaluated in terms of filling ratio and damage value. The filling ratio is defined from the tool geometry and critical damage is determined from the analysis of uniaxial tensile test. Finally, optimum forming conditions that guarantee the successful forming are found.

• The Korean Journal of Pain
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• 제19권2호
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• pp.175-180
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• 2006

Background: A transforaminal epidural steroid injection has been used for the treatment of radicular arm or leg pain, which has the advantage of ventral epidural spreading compared to either an interlaminar or caudal approach. However, several factors are known to affect the epidural spread pattern of contrast dye; therefore, the injected medication can not be delivered to the target site. The objective of our study was to observe any differences in the contrast flow patterns according to several factors. Methods: A total of 34 epidurographies in 29 patients, who underwent fluoroscopically guided transforaminal epidural steroid injections, were evaluated. After confirming the location of the needle tip within the anterior superior aspect of the neural foramen in the lateral view, and at the 6 o'clock position to the pedicle in the anteroposterior view, 2 ml of contrast dye was injected. The contrast flow patterns of ventral, ventral and dorsal, and dorsal epidural filling were analyzed, according to age, gender, magnetic resonance imaging finding and history of previous back surgery. Results: Ventral contrast flow occurred in 30 out of the 34 epidurographies (88%). Both ventral and dorsal contrast flow patterns were observed 13 out of 16 (81%) patients in the older age group. Also, both ventral and dorsal contrast flow patterns were observed in 16 out of 18 (88%) patients with spinal stenosis. Conclusions: Transforaminal epidural steroid injections, performed uner fluoroscopy, provide excellent nerve root filling and ventral epidural spreading. Patients with spinal stenosis or an old age have both ventral and dorsal epidural spreading patterns.

• 한국재료학회지
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• 제26권9호
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• pp.455-459
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• 2016

The deposition process for the gap-filling of sub-micrometer trenches using DMDMOS, $(CH_3)_2Si(OCH_3)_2$, and $C_xH_yO_z$ by flowable chemical vapor deposition (F-CVD) is presented. We obtained low-k films that possess superior gap-filling properties on trench patterns without voids or delamination. The newly developed technique for the gap-filling of submicrometer features will have a great impact on IMD and STI for the next generation of microelectronic devices. Moreover, this bottom up gap-fill mode is expected to be universal in other chemical vapor deposition systems.

• 한국공작기계학회논문집
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• 제18권2호
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• pp.144-153
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• 2009

It is widely known that no-slip assumptions are often violated on regular basis in micrometer- or nanometer-scale fluid flow. In the case of cavity-filling process of nanoimprint lithography(NIL), slip phenomena take place naturally at the solid-to-liquid boundaries, that is, at the mold-to-polymer or polymer-to-substrate boundaries. If the slip or partial slip phenomena are promoted at the boundaries, the processing time of NIL, especially of thermal-NIL which consumes more tact time than that of UV-NIL, can be significantly improved. In this paper it is aimed to elucidate how the cavity-filling process of NIL can be influenced by the slip phenomena at boundaries and to what degree those phenomena increase the process rate. To do so, computational fluid dynamics(CFD) analysis of cavity filling process has been carried out. Also, the effect of mold pattern shape and initial thickness of polymer resist were considered in the analysis, as well.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2682-2687
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• 2008

Depressurized drainage systems have been used for more than 30 years and are becoming a common part of urban drainage infrastructures. The hydraulic principles governing the operation of the depressurized drainage systems were studied in this paper and particularly, focused on the analysis of unsteady characteristics of the two-phase flow. A definition of the filling ratio was outlined and types of flow pattern were classified according to the filling ratio. Experiments were conducted to investigate the main features of pressure fluctuation. All results were found to depend on the filling ratio of the upstream pipe flow as well as the upstream Froude number.