• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.557-559
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• 2004

The aminolyses of anilinothioethers $(C_6H_5N(CH_3)CH_2SC_6H_4Z)$ in acetonitrile with benzylamines $(XC_6H_4CH_2NH_2)$ have been investigated. The rates are much lower in acetonitrile than in methanol (with aniline). The Bronsted ${\beta}_X$ values are similar but ${\beta}_Z$ values are smaller compared to those for the reactions in MeOH with anilines. The large negative ${\rho}_{XZ}({\cong}-0.8$, after correction for fall-off) value is interpreted to indicate a frontside attack $S_N2$ mechanism, in which the two oppositely changed reaction centers in the TS, $-N^{{\delta}+}{\cdots}S^{{\delta}-}-$, are in close vicinity increasing the interaction between nucleophile and leaving group. The inverse secondary kinetic isotope effects ($k_H/k_D$ < 1.0) are observed with deuterated benzylamines $(XC_6H_4CH_2ND_2)$.

• Environmental Engineering Research
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• v.20 no.2
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• pp.155-161
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• 2015

Experimental research shows that the nitric oxides ($NO_X$) concentration track at the outlet of selective catalytic reduction (SCR) catalyst with a transient variation of Adblue dosage has a time delay and it features a characteristic of resistance-capacitance (RC). The phenomenon brings obstacles to get the simultaneously $NO_X$ expected to be reduced and equi-molar ammonia available to SCR reaction, which finally inhibits $NO_X$ conversion efficiency. Generally, engine loads change frequently, which triggers a rapid changing of Adblue dosage, and it aggravates the air quality that are caused by $NO_X$ emission and ammonia slip. In order to increase the conversion efficiency of $NO_X$ and avoid secondary pollution, the paper gives a comprehensive analysis of the SCR system and tells readers the key factors that affect time delay and RC characteristics. Accordingly, a map of time delay is established and a solution method for time constant and proportional constant is carried out. Finally, the paper accurately describes the input-output state relation of SCR system by using "variable RC model with time delay". The model can be used for a real-time correction of Adblue dosage, which can increase the conversion efficiency of $NO_X$ in SCR system and avoid secondary pollution forming. Obviously, the results of the work discover an avenue for the SCR control strategy.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3229-3240
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• 2023

Due to neutron radiation, atomic displacement has a significant effect on material in nuclear reactors. A range of secondary displacement models, including the Kinchin-Pease (K-P), Lindhard, Norgett-Robinson-Torrens (NRT), and athermal recombination-corrected displacement per atom (arc-dpa) have been suggested to calculate the number of displacement per atom (dpa). As neutron elastic interaction is the main cause of displacement damage, the focus of the current study is to calculate the atomic displacement caused by the neutron elastic interaction in order to estimate the exact amount of yield strength in a WWER-1000 reactor pressure vessel. To achieve this purpose, the reactor core is simulated by MCNPX code. In addition, a program is developed to calculate the elastic radiation damage induced by the incident neutron flux (RADIX) based on different models using Fortran programming language. Also, due to non-elastic interaction, the displacement damage is calculated by the HEATR module of the NJOY code. ASME E-693-01 standard, SPECTER, NJOY codes, and other pervious findings have been used to validate RADIX results. The results showed that the RADIX(arc-dpa)/HEATR outputs have appropriate accuracy. The relative error of the calculated dpa resulting from RADIX(arc-dpa)/HEATR is about 8% and 46% less than NJOY code, respectively in the ¼ and ¾ vessel wall.

• Archives of Plastic Surgery
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• v.35 no.4
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• pp.465-470
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• 2008

Purpose: Reduction malarplasty is a popular aesthetic surgery for contouring wide and prominent zygoma. However a few patients complain postoperative results and want to revise the midfacial contour. We analyzed the etiology of unfavorable results and treated unsatisfied midfacial contours after reduction malarplasty. Methods: Total 53 patients were performed secondary operation for correction of unfavorable results after primary reduction malarplasty from elsewhere. Midfacial contour was evaluated with plain films and three-dimensional computed tomography. Unfavorable midfacial contours were corrected by secondary malarplasty. Flaring of zygomatic arch was reduced with infracturing technique and prominent zygomatic body was reduced with shaving. Drooped or displaced zygoma complex has been suspended to higher position and fixed with interosseous wiring. As adjuvant procedure, autologous fat injection has been performed in the region of depressed zygomatic body region. Results: The etiology of unfavorable midfacial contour after reduction malarplasty was classified into 7 categories: undercorrection of zygomatic arch(n=8), undercorrection of zygomatic arch and undercorrection of zygomatic body(n=6), undercorrection of zygomatic arch and overcorrection of zygomatic body(n=28), overcorrection of zygomatic body(n=3), simple asymmetry(n=4), malunion(n=2) or nonunion(n=2). Slim and balanced malar contour was achieved with treatment. And most of the patients were satisfied with the results of the surgery. Conclusion: To prevent the unfavorable results after reduction malarplasty, complete analysis of facial contour, choice of appropriate operation technique, precise osteotomy under direct vision, and security of zygoma position are important.

• Archives of Plastic Surgery
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• v.39 no.3
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• pp.190-197
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• 2012

Background : This article presents long-term outcomes after correcting secondary bilateral cleft lip nasal deformities using a refined reverse-U incision and V-Y plasty or in combination with a composite graft in order to elongate the short columella. Methods : A total of forty-six patients underwent surgery between September 1996 and December 2008. The age of the patients ranged from 3 to 19 years of age. A bilateral reverse-U incision and V-Y plasty were used in 24 patients. A composite graft from the helical root was combined with a bilateral reverse-U incision in the 22 patients who possessed a severely shortened columella. The follow-up period ranged between 2 and 10 years. Results : A total of 32 patients out of 46 were evaluated postoperatively. The average columella length was significantly improved from an average of 3.7 mm preoperatively to 8.5 mm postoperatively. The average ratio of the columella height to the alar base width was 0.18 preoperatively and 0.29 postoperatively. The postoperative basal and lateral views revealed a better shape of the nostrils and columella. The elongated columella, combined with a composite graft, presented good maintenance of the corrected position with no growth disturbance. A composite graft showed color mismatching in several patients. Twenty-six patients demonstrated no alar-columella web deformity and satisfactory symmetry of the nostrils. Four patients experienced a drooping and overhanging of the corrected alar-columella web. Conclusions : A bilateral reverse-U incision with V-Y plasty or in combination with a composite graft was effective in correcting secondary bilateral cleft lip nasal deformity.

• Archives of Craniofacial Surgery
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• v.22 no.2
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• pp.85-92
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• 2021

Background: Patients with secondary deformities associated with unilateral cleft lip and nose might also suffer from nostril stenosis due to a lack of tissue volume in the nostril on the cleft side. Here, we used full-thickness skin grafts (FTSGs) to reduce nostril stenosis and various methods for skin volume augmentation. We compared the changes in the symmetry of both nostrils before and after surgery. Methods: From February 2016 to January 2020, 34 patients underwent secondary cheiloplasty and open rhinoplasty for secondary deformities of the unilateral cleft lip and nose with nostril stenosis. FTSG was used on the nostril floor, nasal columella, and alar inner lining. The measured nasal profile included the nostril surface, nostril circumference, width of the nostril floor, and distance from the alar-facial groove to the nasal tip. The "overlap area," which was defined as the largest overlapping area when the image of the cleft nostril was flipped to the left and right and overlaid on the image of the normal side nostril, was also calculated. The degree of symmetry was evaluated by dividing the value of the cleft side by that of the normal side of each measured profile and expressed as "ratios." Results: The results of all profile ratios, except for the nostril floor width, became significantly close to 1, which represents full symmetry. The overlap area ratio improved from 62.7% to 77.3%, meaning that the length and width of the nostril as well as the overall shape became similar (p< 0.05). Conclusion: When performing cleft rhinoplasty with nostril stenosis, FTSG is useful to achieve symmetry in the nostril size and shape. Skin grafting is simpler to perform than the other types of local flap, and the results are generally satisfactory.

• Korean Journal of Optics and Photonics
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• v.31 no.6
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• pp.304-313
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• 2020

By using an off-axial field with an inverse Cassegrain system where the aperture stop is at the secondary mirror, the two-mirror system can be used for a wide-field objective. However, aberration corrections in conventional two-mirror systems are limited because the design parameters are too small. In this study, we present a new improved design of the off-axial-field two-mirror system. The new design has an independently displaced aperture stop and a secondary mirror. The new design parameters yield more improvement in correction for 5th-order coma and astigmatism, and better aberration balancing for the whole off-axial field. The spot sizes of the new design system are reduced to half of those for a conventional reference design, and the improvement effects are shown for the whole field evenly.

• Journal of Astronomy and Space Sciences
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• v.18 no.1
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• pp.55-62
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• 2001

We present VRI CCD photometry of W UMa type binary TY UMa. The light curves show that the secondary minimum is deeper than the primary minimum and the maximum I ($0.^{p}25$)is $0.^{m}023$ brighter than the maximum II ($0.^{p}75$). The V light curve has been analyzed and the photometric solutions have been determined by the method of Wilson & Devinney differential correction. We adopted the spot model to explain the asymetric light curve.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.2
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• pp.153-158
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• 1995

A wide variety of deformities can occur following repair of the cleft lip. Especially, cleft lip nasal deformities offer the severe psychologic, esthetic, and functional impairment. We must restore the deformities of alar cartilge, nasal tip, septum, columella, or pyriform aperture. The authors reconstructed the cleft lip nasal deformities using with the alar cartilage rearrangement, postauricular cartilage graft, and/or columellar lengthening. The 3 case reports are presented.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.9
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• pp.953-959
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• 1992

As the TC(time-current) curve corresponding to symmetrical time invariant RMS value has been traditionally chosen and used for setting the relay, it has caused the misoperation errors on relay coordination because of CT secondary current being actually an asymmetrical time varying RMS value. In this paper, an algorithm for calculating the relay operating time is developed to study the asymmetrical effect using the step-by-step method. We represent the relay operating time errors between with and without DC offset versus PSM(plug setting multiplier), TMS(time multiplier setting) and X/R ratio. And also we present the correction factor. Finally we confirm the validity of this technique through the case study.