• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.251.1-251.1
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• 2013

Combination of oxidative vacuum annealing and oxygen plasma treatment can serve as a simple and efficient method of line-width modification of imprinted nanopatterns. Since the vacuum annealing and oxygen plasma could lead mass loss of polymeric materials, either one of the process can yield a narrowed patterns. However, the vacuum annealing process usually demands quite high temperatures (${\geq}300^{\circ}C$) and extended annealing time to get appreciable line-width reduction. Although the plasma treatment may be considered as an effective low temperature rapid process for the line-width reduction, it is also suffering for the lowered controllability on application to very fine patterns. We have found that the vacuum annealing temperature can be lowered by introducing the oxygen in the vacuum process and that the combination of oxygen plasma treatment with the vacuum annealing could yield the best result in the line-with reduction of the imprinted polymeric nanopatterns. Well-defined line width reduction by more than 50% was successfully demonstrated at relatively low temperatures. Furthermore, it was verified that this process was applicable to the nanopatterns of different shapes and materials.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4266-4273
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• 2023

In a severe reactor accident, a crust will form on the surface of the molten material during the core melting process. The crust will have a contact melting with the internal components of the reactor. In this paper, the contact melting process of the molten material on the austenitic stainless steel plate bundles is studied. The contact melting model of parabolic molten material on the plate bundles is proposed, and the rule and main effect factors of the contact melting are analyzed. The results show that the melting velocity is proportional to the slope of the paraboloid, the heat flux and the distance between two plates D. The influence of melt gravity and the plate width on melting velocity is negligible. The thickness of the molten liquid film is proportional to the heat flux and plate width, and it is inversely proportional to the gravity. With the increase of D, the liquid film thickness decreases at first and then increases gradually. The liquid film thickness has a minimum against D. When the width of the plate is small, the width of the plate is the main factor affecting the thickness of the liquid film. The parameters are coupled with each other. In a severe reactor accident, the wider internal components of reactor, which can increase the thickness of the melting liquid film and reduce the net input heat flux from the molten material to the components, are the effective measures to delay the melting process.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2004.11a
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• pp.126-129
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• 2004

We compared intensity-modulated radiotherapy (IMRT) treatment plans with commercially available multileaf collimators (MLCs) of different leaf width for intracranial lesions. Twelve cases previously treated with micro-MLCs(mMLCs) were replanned using the Varian 120 and 80 MLCs. These collimators have minimum leaf width of 3mm, 5 mm and 10 mm at isocenter, respectively. These three plans were compared with respect to the uniformity and the conformity indices, doses to normal tissue. For the uniformity index of planning target volume (PTV),there was no statistically significant difference between mMLCs with 120 MLCs (p = 0.06). However, there was a little difference between mMLCs with 80 MLCs (p = 0.001). Maximum target dose to the PTV showedno dependency with respect to the leaf width. On the contrary, there were statistically significant differences in the conformity indices between mMLCs and 120 MLCs (p = 0.003) and between mMLCs and 80 MLCs (p = 0.003).The volumetric increments for MLCs with leaf widths of 5 mm and 10 mm were 6.3% and 23.2% for the normal tissue Irradiated to = 50% dose, and 8.7% and 32.7% for the normal tissue Irradiated to = 70% dose, respectively, compared to the volume for MLCs with leaf width of 3 mm. This shows that for the sparing of normal tissue, MLCs with leaf width of 3 mm are more effective, compared to MLCs with leaf widths of 5 mm and 10 mm.

• Journal of Korean Physical Therapy Science
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• v.25 no.2
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• pp.47-54
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• 2018

Purpose: The purpose of this study was to investigate the most effective exercise position of Latissimus dorsi's activities during Pull up, Push up and Lat pull down among few positions of hand grips(pronation, Supination and neutral grip) and grip widths(30cm, 60cm) based on EMG activities. Method: 10 healthy adults were participated in this study and the surface EMG activities of the Latissimus dorsi were measured during Pull up, Push up and Lat pull down exercise according to specific hand grip and grip width positions. The maximum and mean value of Latissimus dorsi's EMG activities at all positions were recorded and analysed by ONE-WAY REAPTED ANOVA. Results: The showed that the most Latissimus dorsi's activities is during Pull up exercise. Main results are as follows 1)maximum value: For Pull up, among all studied positions, Rt Latissumus dorsi, position of Supinated grip and 60cm grip width showed strongest muscle activation based on maximum EMG value. Statistical significance was assumed at p<.05. 2)mean value: For Pull up, among all studied positions, Both Latissimus dorsi, position of pronated grip and 60cm grip width showed strongest muscle activation based on mean EMG value. Statistical significance was assumed at p<.05. Conclusion: Therefore, taking the results of this study, Pull up exercise would be the best exercise of Latissimus dorsi's activation. It is recommended to do in pronated grip position and 60cm grip width during Pull up to make body fit.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.11
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• pp.575-580
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• 2001

In this paper, using $500\mum-thickness\; (100)\; silicon\; wafer,\; flat\; 65\mum-thickness$ silicon mirror plates were fabricated through dry etching and wet etching, and $45\mum-depth$ grooved driving electrodes were fabricated through UV-LIGA process. Four shapes of the driving electrode were fabricated: twenty four grooves of the $50\mum-width$, twelve grooves of the $100\mum-width$, six grooves of the $200\mum-width$, and no grooves on the driving electrode. Fabricated mirror plate size and spring size are $2400\times2400\times65\mum3\; and \;500\times10\times65\mum3,$ respectively. Mirror plate parts and driving electrodes were assembled into the scanning mirrors. Measured natural resonance frequencies were about 600Hz which have error within $\pm 2%$ to calculated value. Due to the squeeze effect in the narrow gap between the mirror plate and the driving electrode, measured resonance frequencies were reduced as raising the amplitude of the mirror plate. In a case of driving electrode without grooves, the resonance frequency was reduced largely, compared with a case of driving electrode with grooves. According to the experimental results, squeeze effect was smaller in the driving electrode with smaller-width and many grooves. Therefore, the driving electrode with smaller-width and many grooves was effective in low voltage and high speed operation.

• Journal of Life Science
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• v.8 no.4
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• pp.431-436
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• 1998

These studies were carried out to obtain useful information about the effective selection of vegetable perilla by estimating the genetic relationships between the heritabilities and the genetic correlations of quantitative traits among eight agronomic characters from 91 perilla varieties. The positive correlations were showed among characters such as between leaf weight and leaf size, leaf weight and leaf length, leaf weight and leaf width, leaf weight and plant height, leaf weight and stem diameter, leaf size and leaf length, leaf size and leaf width, leaf size and plant height, leaf size and stem diameter , leaf length and leaf width, leaf length and plant height, leaf length and stem diameter, leaf width and plant height, leaf width and stem diameter, plant height and stem diameter, plant height and the number of internodes per plant, and the number of internodes per plant and the number of leaves per plant. Heritabilities were high as from 0.7311 to 0.9112 among leaf weight, leaf size, leaf length, leaf width, plant height, stem diameter, and the number of internodes per plant.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.2
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• pp.129-137
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• 2006

The treatment plan for orthognathic surgery must be based on accurate predictions, and this can be produced the most esthetic, functional and stable results. The purpose of this study was aimed to evaluate the amount and interrelationship of the gonial angle and the mandibular width change after the mandibular setback surgery in the mandibular prognathic patients. Twenty patients were selected who received orthognathic surgery after presurgical orthodontic treatment. The patients with skeletal and dental Class III malocclusion were operated upon with bilateral sagittal split ramus osteotomy and mandibular setback. The lateral and posteroanterior cephalometric radiographs were taken preoperatively, postoperative 1 day and 12 months later after the orthognathic surgery, and then the gonial angle and mandibular width were measured. The computerized statistical analysis was carried out with SPSS/PC program. The gonial angle at postoperative 1 day was decreased about $5.3^{\circ}$ than preoperative value and the gonial angle at postoperative 12 months was increased about $1.4^{\circ}$ than postoperative 1 day. So the gonial angle at postoperative 12 months was decreased about $3.9^{\circ}$ than preoperative value. The mean preoperative gonial angle was $125.35^{\circ}{\pm}7.36$, showing significantly high value than normal and mean gonial angle at postoperative 12 months was $121.45^{\circ}{\pm}6.81$, showing value near to normal. The mandibular width at postoperative 1 day was decreased about 1.1 mm than preoperative value and the mandibular width at postoperative 12 months was more decreased about 1.7 mm than postoperative 1 day. So the mandibular width at postoperative 12 months was decreased about 2.8 mm than preoperative value. These results indicate that sagittal split ramus osteotomy in mandibular prognathic patients with high gonial angle is effective to improvement of gonial angle. It is considered to be helpful for maintenance of postoperative stable gonial angle area that detailed postoperative care and follow-up.

• Progress in Medical Physics
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• v.15 no.4
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• pp.173-178
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• 2004

Purpose: To compare desimetrically intensity-modulated radiotherapy treatment plans with commercially available multileaf collimators (MLCs) of different leaf width for intracranial lesions. Materials and Methods: Twelve patients with intracranial lesions were treated with BrainLAB's micro-MLCs (mMLCs) and performed with the BrainSCAN ver. 5.2 planning software. They were replanned using the Varian 120 and 80 MLCs. These collimators have minimum leaf width of 3 mm, 5 mm and 10 mm at isocenter, respectively. PTV was $3.3~339.2\textrm{cm}^3$ and the number of beams was 3~7. These three plans were compared with respect to the uniformity and the conformity indices, doses to critical organ and normal tissue. Results: For the uniformity index of the planning target volume (PTV), there were no statistically significant differences between mMLCs and 120 MLCs (p=0.057) and between 120 MLCs and 80 MLCs (p=0.388). However, there was a difference between mMLCs and 80 MLCs (p<0.001). Maximum target dose to the PTV showed no dependency with respect to the leaf width. On the contrary, there were statistically significant differences in the conformity indices between mMLCs and 120 MLCs (p=0.003), between mMLCs and 80 MLCs (p=0.003) and between 120 MLCs and 80 MLCs (p=0.003). The volume of brainstem irradiated to $\geq$70% dose and to $\geq$50% dose was increased as the leaf width of MLCs increased. In particular, the volume of normal tissue irradiated is obviously changed for different leaf width. Volumetric increments for MLCs with leaf widths of 5 mm and 10 mm were 6.3% and 23.2% to the normal tissue irradiated to $\geq$50% dose, and 8.7% and 32.7% to the normal tissue irradiated to $\geq$70% dose, respectively, compared to the volume for MLCs with leaf width of 3 mm. Conclusions: The uniformity index and maximum target dose to the PTV showed no dependency with respect to leaf width of MLCs. However, the conformity index was improved as the leaf width decreased. For the sparing of normal brain tissue, treatment plans with MLCs of 3 mm leaf width is more effective, compared to ones with MLCs of 5 mm and 10 mm leaf widths.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.9
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• pp.343-349
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• 2016

Due to the recent increase in lighting energy consumption in buildings, there are a growing number of studies seeking solutions this problem. The effectiveness of light-shelves as natural lighting systems to solve this problem has been recognized, and various studies regarding such systems are being carried out currently. However, the lighting efficiency of light-shelves decreases if illumination intensity is low-such as at night time, and it also obstructs the views of building occupants. Therefore, the purpose of this study is to examine a movable drawer type light-shelf which allows for the width of the reflector to be adjusted and verify its performance through a simulated test-bed. The following conclusions were reached. 1) The purpose of this study is to solve the problem previously associated with the light-shelf system- of obstructed views-by responding to external environments and minimizing the width of the light-shelf at night time when the efficiency of the light-shelf declines. 2) The proper variables of the movable drawer type light-shelf which enables the width adjustment of the reflector were ascertained in this study according to four solar terms : a width of 0.6 m at an angle of $20^{\circ}$, a width of 0.4m with an angle of $20^{\circ}$, and a width of 0.1 m with an angle of $20^{\circ}$ were determined for the summer solstice, fall/spring equinoxes, and winter solstice respectively; revealing that width adjustment of the light-shelf is a significant factor. 3) The movable drawer type light-shelf which enables${\backslash}$width adjustment of the reflector suggested in this study can reduce the lighting energy consumption by 18.7% and 14.3% in comparison to previous light-shelves with a fixed width of 0.3 m and 0.6m, indicating that it is effective for saving energy.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.3 s.357
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• pp.6-11
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• 2007

This paper proposes CMOS optical receivers to reduce effective area and pulse width distortion (PWD) in high definition digital audio interfaces. To mitigate effective area and PWD, proposed receivers include a frans-impedance amplifier (TIA) with dual output and a level shifter with threshold convergence, respectively. Proposed circuits are fabricated using $0.25{\mu}m$ CMOS process and measured result demonstrated the effective area of $270\times120{\mu}m^2$ and PWD of ${\pm}3%$ for the receiver with a dual output TIA, and the effective area of $410\times140{\mu}m^2$ and PWD of ${\pm}2%$ for the receiver with a threshold convergence level shifter.