• Journal of Animal Science and Technology
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• v.56 no.7
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• pp.24.1-24.6
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• 2014

The present study investigated the effects of varying durations of nursery diets differing in percentages of milk products on growth performance of pigs during the nursery phase (NP) and subsequent grow-finish phase (GFP) to find the feasibility of reducing the use of nursery diets containing costly milk products. A total of 204 21-d-old weanling female and castrated male pigs were subjected to one of three nursery phase feeding programs differing in durations on the NP 1 and 2 and GFP diets containing 20%, 7%, and 0% lacrosse and 35%, 8%, and 0% dried whey, respectively, in 6 pens (experimental units) for 33 d: HIGH (NP 1, 2 and 3 diets for 7, 14, and 12 d), MEDIUM (NP 2 and 3 for 14 and 19 d), and LOW (NP 2 and 3 and GFP 1 for 7, 14, and 12 d). Subsequently, 84 randomly selected pigs [14 pigs (replicates)/pen] were fed the GFP 1, 2 and 3 diets during d 54-96, 96-135, and 135-182 of age, respectively. The final body weight (BW) and average daily gain (ADG) of nursery pigs did not differ among the HIGH, MEDIUM, and LOW groups (14.8, 13.3, and 13.7 kg in BW and 273, 225, and 237 g in ADG, respectively). The average daily feed intake during the nursery phase was greater (p < 0.01) in the HIGH group than in the MEDIUM and LOW groups, whereas the gain:feed ratio did not differ across the treatments. The BW on d 182 and ADG during d 54-182 were greater in the HIGH and MEDIUM groups vs. the LOW group (110.0, 107.6, and 99.6 kg in BW, respectively; p < 0.01). The backfat thickness and carcass grade at slaughter on d 183 did not differ across the treatments. In conclusion, the MEDIUM program may be inferior to the commonly used HIGH program in supporting nursery pig growth. Nevertheless, the former appears to be more efficient than the latter in production cost per market pig whereas the LOW program is thought to be inefficient because of its negative effect on post-nursery pig growth.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.4
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• pp.457-463
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• 2012

Current refrigerators are designed to have thin doors and walls to facilitate user convenience and increase inner storage space. However, the thin doors and walls gives rise to the problem of dew generation on the outer surface of a refrigerator due to a large critical temperature difference between the outer wall and the room air; So far, an electric heater is commonly used for making the dew to evaporate; in this case, the heater inevitably requires additional electrical power. We propose a new approach to reduce the dew generation in a refrigerator by redesigning the gasket and varying the thickness of the inner case of the refrigerator. The results of simulations performed in this study indicate that the surface temperature in the region where dew was generated was increased by approximately $0.39{\sim}3.07^{\circ}C$ without the use of a heater.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.313-313
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• 2012

In recent years there have been many studies of InGaN/GaN based light emitting diodes (LEDs) in order to progress the performance of luminescence. Many previous literatures showed the performance of LEDs by changing the LED structures and substrates. However, the studies carried out by the researchers so far were very complicated and sometimes difficult to apply in practice. Therefore, we propose one simple method of changing the thickness and the numbers of multiple quantum wells (MQWs) in order to optimize their effects. In our research, we investigated electrical and optical properties by changing the well thickness and the number of quantum well (QW) pair in LED structures by growing the structure -inch Si (111) wafer. We defined the samples from LED_1 to LED_3 according to MQW structure. Samples LED_1, LED_2 and LED_3 consist of 5-pair InGaN/GaN (3.5 nm/ 4.5 nm), 5-pair InGaN/GaN (3 nm/4.5 nm) and 7-pair InGaN/GaN (3.5 nm/4.5 nm), respectively. We characterized electrical and optical properties by using electroluminescence (EL) measurement. Also, Efficiency droop was analyzed by calculating external quantum efficiency (EQE) with varying injection current. The EL spectra of three samples show different emission wavelength peaks, FWHM and the blueshift of wavelength caused by screening the internal electric field because of the effect of different MQW structure. The results of optical properties show that the LED_2 sample reduce the internal electric field in QW than LED_1 from EL spectra. the increase in the number of QW pairs reduces the strain and increase the In composition in MQW. And, the points of efficiency droop's peak show different trend from LED_1 to LED_3. It is related with the carrier density in active region. Thus, from the results of experiments, we are able to achieve high performance LEDs and a reduction of efficiency droop and emission wavelength blueshift by optimizing MQWs structure.

• Journal of dental hygiene science
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• v.12 no.2
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• pp.123-129
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• 2012

The aim of study was to compare the color parameters and mean color difference of porcelain specimens by different veneering technique in order to examine the effect of veneering technique on esthetics of yttria-stabilized tetragonal zirconia polycrystalline(Y-TZP) all ceramic restoration. Three groups of square-shaped core ceramic specimens(14mm in diameter and 0.3, 0.5, 0.7 mm) and two groups of veneering ceramic specimen were prepared for analysis. Color parameter($L^*,a^*,b^*$) and color difference of zirconia core squares and core-veneer specimens were measured with ShadeEye $NCC^{(R)}$ spectrophotometer, respectively. Mean color difference(${\Delta}E^*$)were calculated using color difference formula. Two-way analysis of variance(ANOVA) combined with a Tukey multiple-range test were used to analysis the data(${\alpha}=0.05$). ${\Delta}E^*$ values were not significantly affected by core thickness and veneering porcelain(p=0.083). The color differences(${\Delta}E^*$) of core-veneer specimens with 0.5, 0.7 mm-A1,A2,A3.5 shade were mostly below 3.7 which was within the clinically acceptable range, while color differences between 0.3 mm-A1,A2 showed more than 3.7. All-ceramic system has color characteristics that clinicians have to consider when selecting materials. Also, manufacturers of different porcelain systems must make every effort to achieve color reproducibility.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.601-608
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• 2014

In this paper, we have characterized the electrical properties related to gate leakage current in AlGaN/GaN MISHFETs with varying the thickness (0 to 10 nm) of $Al_2O_3$ gate insulator which also serves as a surface protection layer during high-temperature RTP. The sheet resistance of the unprotected TLM pattern after RTP was rapidly increased to $1323{\Omega}/{\square}$ from the value of $400{\Omega}/{\square}$ of the as-grown sample due to thermal damage during high temperature RTP. On the other hand, the sheet resistances of the TLM pattern protected with thin $Al_2O_3$ layer (when its thickness is larger than 5 nm) were slightly decreased after high-temperature RTP since the deposited $Al_2O_3$ layer effectively neutralizes the acceptor-like states on the surface of AlGaN layer which in turn increases the 2DEG density. AlGaN/GaN MISHFET with 8 nm-thick $Al_2O_3$ gate insulator exhibited extremely low gate leakage current of $10^{-9}A/mm$, which led to superior device performances such as a very low subthreshold swing (SS) of 80 mV/dec and high $I_{on}/I_{off}$ ratio of ${\sim}10^{10}$. The PF emission and FN tunneling models were used to characterize the gate leakage currents of the devices. The device with 5 nm-thick $Al_2O_3$ layer exhibited both PF emission and FN tunneling at relatively lower gate voltages compared to that with 8 nm-thick $Al_2O_3$ layer due to thinner $Al_2O_3$ layer, as expected. The device with 10 nm-thick $Al_2O_3$ layer, however, showed very high gate leakage current of $5.5{\times}10^{-4}A/mm$ due to poly-crystallization of the $Al_2O_3$ layer during the high-temperature RTP, which led to very poor performances.

• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.130-136
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• 1986

'Shingo' pears were seal-packaged in polyethylene (PE) film with different thickness of 0.04. 0.06, 0.07, and 0.08mm and stored for five months in an experimental storehouse with the temperature varyine 0 to $7^{\circ}C$ and relative humidity varying 86 to 89%. The atmosphere in PE film bags was modified to 5-l4% oxygen with 3-5% carbon dioxide depending on the film thickness and the storage period. Packaging of pears with PE film effectively reduced the weight loss, which resulted in good appearance after 5 months' storage, while non-packaged pears showed a slight wilt. Decay occurrence was not significantly different among the treatments. but role browning occurred a little more in packaged lots than in non-packaged lot. The sensory panel rated the pears front 0.07mm-thick bag highest in flavor, texture, and juiciness, which might be due to the high sugar content and low titratable acidity. The firmness of pear flesh decreased with the stogare time and its change was found to be highly correlated with that of cellulase activity (correlation coefficient= -0.946). Thisresult indicated that cellulase might be one of the enzymes responsible for the softening of pear fruit during storage.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.5-13
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• 2008

Purpose: This review article was written to investigate what kind of forces are acting on the contact lens fitted on the cornea and its subsequent motion. Methods: A capillary action-induced force develops in the tear layer between the lens and cornea, which leads to the restoring force due to difference in layer thickness according to lens rotation. The characteristics of the lens movement can be determined by the various factors such as friction between eyelid and lens, acceleration force based on blinking and the restoring force incorporated with the viscous damping force. A mathematical model which consists of the differential equations and their numerical solution was proposed to analyze the damped motion of lenses. The model predicts the time dependence of lenses during and after the blink varying the BC, blink period and eyelid pressure. Results: It was found that both the blink period and lid pressure increases the movement increases because of the enhanced lid friction. As the BC increases the viscous damping reduces due to the lacrimal layer's increase which resulted in the enhanced lens motion. After blink the lens illustrates the damped oscillation because of the restoring force by the increased lacrimal layer thickness and reduced viscous resistance. The time for the lens to return to the equilibrium shortens as the BC increase because of the resistance reduction. Conclusions: The movement of the contact lens is governed by the characteristics of the lacrimal layer between the lens and cornea as well as the lid blink.

• Journal of radiological science and technology
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• v.32 no.1
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• pp.53-60
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• 2009

This study examined the change in the attenuation of X-rays with the ROI (Region of Interest) in DR (Digital Radiography) according to the stomach contents by manufacturing a tissue equivalent material phantom to simulate real stomach tissue based on the assumption that there is some attenuation of X-rays and a difference in imaging quality according to the stomach contents. The transit dosage by the attenuation of X-rays decreased with increasing protein thickness, which altered the average ROI values in the film and DR images. A comparison of the change in average ROI values of the film and DR image showed that the image in film caused larger density changes with varying thickness of protein than the image by DR. The results indicate that NPO (nothing by mouth) is more important in film system than in DR system.

• Journal of the Korean Magnetics Society
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• v.20 no.5
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• pp.191-195
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• 2010

We have investigated the effect of the removal of an initial oxide layer and the anodization time on the growth of the porous alumina layer. The porous alumina layer was fabricated by two-step anodization process with phosphoric acid. We have observed the changes in the uniformity of the pore structure by varying the removing time of the initial oxide layer after the first anodization with phosphoric acid and chromic acid, and noted that its uniformity improves with the removing time. We have also determined the thickness of the alumina layer after the final anodization process and found that the thickness increases linearly with the anodization time. Under 150 V of anodization voltage with phosphoric acid, the growth rate of the porous alumina layer is determined to be 22.5 nm/min.

• Journal of Acupuncture Research
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• v.31 no.4
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• pp.109-119
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• 2014

Objectives : The aim of this study is to observe clinical characteristics and treatment outcomes of inpatients admitted to a Korean medicine hospital for shoulder pain based on magnetic resonance imaging(MRI) findings. Methods : 28 patients with MRI data were included. Data on MRI findings, duration of pain, and treatment effects were collected. To measure treatment outcomes, verbal numerical rating scale(VNRS), range of motion(ROM), and a clinical condition grading system were used. Results : 1. The patient population was 75.0 % female and 39.3 %(n=11) belonged to the 51~60-year-old age group. In the under 40 population, 1 or less MRI findings were found. 2. As for the type of disorder, 82.1 % of the patients were diagnosed with 'Supraspinatus lesion', 39.3 % with 'subacromial-subdeltoid(SA-SA) bursitis', and 28.6 % with 'Adhesive capsulitis' 3. Numerous correlations could be made between duration of pain and MRI findings. 'rotator cuff full thickness tear' was more prevalent in acute shoulder pain patients, and 'Adhesive capsulitis' in chronic patients. 4. VNRS and ROM at the time of discharge had significantly improved as compared to VNRS and ROM at the time of admission. 5. As for correlation between MRI findings and clinical condition grade, patients diagnosed with 'rotator cuff partial tear' reported to be in 'good' condition or better whereas those with 'rotator cuff full thickness tear' reported to be in 'fair' condition or worse. Conclusions : Patients admitted to a Korean Medicine hospital for shoulder pain had varying degrees of severity as shown on MRI. Almost all lesions responded well to Korean medicine treatment.