• Journal of Power Electronics
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• v.14 no.5
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• pp.1047-1056
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• 2014

In most grid-connected inverters (GCI) with an LCL filter, since the design of both the LCL filter and the controller is done separately, considerable tuning efforts have to be exerted when compared to inverters using an L filter. Consequently, an integrated co-design of the filter and the controller for an LCL-type GCI is proposed in this paper. The control strategy includes only a PI current controller and a proportional grid voltage feed-forward controller. The capacitor is removed from the LCL filer and the design procedure starts from an L-type GCI with a PI current controller. After the PI controller has been settled, the capacitor is added back to the filter. Hence, it introduces a resonance frequency, which is identified based on the crossover frequencies to accommodate the preset PI controller. Using the proposed co-design method, harmonic standards are satisfied and other practical constraints are met. Furthermore, the grid voltage feed-forward control can bring an inherent damping characteristic. In such a way, the good control performance offered by the original L-type GCI and the sharp harmonic attenuation offered by the latter designed LCL filter can be well integrated. Moreover, only the grid current and grid voltage are sensed. Simulation and experimental results verify the feasibility of the proposed design methodology.

• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.689-698
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• 2011

In South Korea, Total Maximum Daily Load (TMDL) has been enforced since 2004 to restore and manage water quality in the watersheds. However, the appraisal of TMDL in South Korea has lots of weaknesses to establish the plan for recovery of water quality because it just evaluates the target water quality during the particular flow duration interval. In the United States, Load Duration Curve (LDC) method bas been widely used in the TMDL to evaluate the water quality and pollutant loads considering variation of stream flow. In a recent study, web-based Load Duration Curve system was developed to create the LDC automatically and provide the convenience of use. In this study, web-based Load Duration Curve system was applied in the Gapyeongcheon watershed using the daily flow and 8-day interval water quality data, and Q-L Rating Curve was used to evaluate the water quality and pollutant load in the watershed, also. As a result of study, water quality and pollutant load in Gapyeongcheon watershed were met with water quality standard and allocated load in the all flow durations. Web-based Load Duration Curve system could be applied to the appraisal of South Korean TMDL because it can be used to judge the impaired flow duration and build up the plan of load reduction, and it could enhance the publicity. But, web-based Load Duration Curve system should be enhanced through addition of load assessment tools such as Q-L rating curve to evaluate water quality and pollutant load objectively.

• Clinics in Shoulder and Elbow
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• v.26 no.2
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• pp.109-116
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• 2023

Background: Golf is a popular sport involving overhead activity and engagement of the rotator cuff (RC). This study aimed to determine to what level golfers were able to return to golf following RC repair, the barriers to them returning to golf and factors associated with their failure to return to golf. Methods: Patients preoperatively identifying as golfers undergoing RC repair at the study centre from 2012 to 2020 were retrospectively followed up with to assess their golf-playing status, performance and frequency of play and functional and quality of life (QoL) outcomes. Results: Forty-seven golfers (40 men [85.1%] and 7 women [14.9%]) with a mean age of 56.8 years met the inclusion criteria, and 80.1% were followed up with at a mean of 27.1 months postoperatively. Twenty-nine patients (76.3%) had returned to golf with a mean handicap change of +1.0 (P=0.291). Golf frequency decreased from a mean of 1.8 rounds per week preinjury to 1.5 rounds per week postoperatively (P=0.052). The EuroQol 5-dimension 5-level (EQ-5D-5L) index and visual analog scale (EQ-VAS) score were significantly greater in those returning to golf (P=0.024 and P=0.002), although functional outcome measures were not significantly different. The primary barriers to return were ipsilateral shoulder dysfunction (78%) and loss of the habit of play (22%). Conclusions: Golfers were likely (76%) to return to golf following RC repair, including mostly to their premorbid performance level with little residual symptomatology. Return to golf was associated with a greater QoL. Persistent subjective shoulder dysfunction (78%) was the most common barrier to returning to golf.

• The korean journal of orthodontics
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• v.54 no.2
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• pp.89-107
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• 2024

Objective: This systematic review aimed to provide a comparative analysis of the treatment outcomes, including hard and soft tissues, postoperative stability, temporomandibular disorders (TMD), and quality of life (QoL), in patients with facial asymmetry who underwent orthognathic surgery. Methods: The primary objective was to address the question, "How do different factors related to surgery affect the outcomes and stability of orthognathic surgery in the correction of facial asymmetry?" A meta-analysis was conducted on the outcome parameters, such as skeletal, dental, and soft tissue symmetry, TMD, QoL, and relapse, using the Hartung-Knapp-Sidik-Jonkman method for random-effects models. Subgroup analyses were conducted considering surgery-related factors such as surgical techniques (one-jaw vs. two-jaw), use of the surgery-first approach, utilization of computer simulation, and analytical methods employed to evaluate asymmetry (2D vs. 3D). Results: Forty-nine articles met the inclusion criteria. The metaanalysis demonstrated a significant improvement in the symmetry of hard and soft tissues. The subgroup analysis indicated that the treatment outcomes showed significant improvement, regardless of the factors related to surgery. Changes in TMD signs and symptoms varied according to the surgical technique used. Quality of life improved in the facial, oral, and social domains. Skeletal relapse was observed during the follow-up. Conclusions: Our findings support the positive outcomes of orthognathic surgery in the treatment of facial asymmetry in terms of skeletal and soft tissue improvements, stability, relief of TMD symptoms, and enhancement of QoL. However, most of the included studies showed a low certainty of evidence and high heterogeneity.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.159-164
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• 2009

Purpose: The automatic notification system for alarm values on blood tests conducted by this hospital is designed to immediately inform the attending physician of the result of a blood test, to help the relevant patient to promptly receive proper treatment, and furthermore, to reduce the likelihood of a fatal influence to the patient. From 2004, the clinical pathology department of this hospital has been operating an automatic notification system for blood tests, in relation to the items of WBC, Hb, Plt, PB cell morphology, Malaria, PT, aPTT, BT, fibrinogen, Ca, K, Na, Cl, Mg, Glucose, Ketone, Digoxin, PKU, Homocystinuria, 17-OHP, Neonatal TSH, and Galactosemia. Recently, the blood test room of the nuclear medicine department has been operating an automatic notification system for the alarm values of a blood test, in relation to three items of TSH, FT4, and 17-${\alpha}$-OH-PGR, and the details of its operation will be described here. Materials and Methods: The subjects were newborn babies that were receiving TSH, FT4, and $17{\alpha}$-OH-PGR prescriptions from February $19^{th}$ to May $11^{st}$, 2009, and who met with the following criteria: N2340 Thyroid-Stimulating Hormone: >$10{\mu}IU/mL$ (Reference value: 0.4~5.0). N2360 Free-Thyroxine: <$0.8{\mu}g/dL$ (Reference value: 0.8~1.9), N2444 $17{\alpha}$-OH-Progesterone: >$30\;{\mu}g/mL$ (Reference value: Male (0.6~3.42), Female follicular phase (0.19~1.8). The automatic notification system was operated by entering test items, relevant treatment departments, and standard values for reporting alarm values into the OCS program, and then transmitting results that met with the input conditions to the PDAs of the prescription and the attending physician by SMS. Results: Reporting an alarm value of the nuclear medicine blood test, which can have a fatal influence on the lives of patients, will help cure patients, improve the quality of the test, and furthermore, will increase the patient's satisfaction with the prescription and treatment of the test.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.49-58
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• 2014

This study investigates mineral contents and sensory properties of commercial bottled water in Korea. The contents of calcium and magnesium in the samples were determined 3.399-85.470 and 2.619-27.390 mg/L, respectively. The mineral contents of bottled water samples met the code of regulations for drinking water, for the hardness was determined 19.2-326 mg/L and the pH was measured as 6.31-7.74. As the sensory characteristics of bottled water samples were evaluated by 5-point hedonic scale, the samples which were below 100 mg/L of hardness had high acceptability. The acceptability was positively correlated with freshness (r=0.706) and sweetness (r=0.253), having a negative correlation with metallic taste (r=-0.402) and astringency (r=-0.234) (p<0.05). On the other hand, calcium content had a negative correlation with acceptability and freshness (p<0.05). The pH of the bottled water represented a negative correlation with acceptability and freshness, so the good acceptability and freshness were shown in the low pH, positively correlated with the intensity of metallic taste (p<0.05).

• Food Science of Animal Resources
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• v.27 no.3
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• pp.267-276
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• 2007

This study was conducted to determine the effect of cryoprotectants (sugar, sorbitol, polyphosphate) on the physico-chemical characteristics of chicken breast surimi manufactured by pH adjustment (pH 11.0) during freezing storage. The final surimi was divided into experimental units to which the following treatments were randomly assigned: C (Alaska pollack surimi: two washings, 4% sugar +5% sorbitol ${\pounds}'$ 0.3% polyphosphate additive): T1 (chicken breast surimi: pH 11.0 adjusted, 0.3% polyphosphate additive): T2 (chicken breast surimi pH 11.0 adjusted, 5% sorbitol +0.3% polyphosphate additive); T3 (chicken breast surimi: pH 11.0 adjusted, 4% sugar +5% sorbitol +0.3% polyphosphate additive). The crude protein content of the control was higher than all treated samples, however the moisture, crude fat and crude ash of T3 were higher than the control (p<0.05). The pH, WHC and collagen content of the control were higher than all of the treated samples, and these values decreased with storage time for all treatments and the control (p<0.05). The cholesterol content of the control was lower than all treated samples, but the myofibrillar protein contents of all treated samples were higher than the control (p<0.05). The cooking loss of T2 was lower than the control and the other two treatments (p<0.05). The $L^*,\;a^*\;and\;b^*$ values of all treated samples were higher than those of the control during freezing storage (p<0.05). The W value of T3 at 1.5 and 3 months of freezing storage was higher than the control and T1 (p<0.05). The myoglobin and met-Mb contents of the control were similar to all treated samples, and the met-Mb content of the control and all treated samples increased with storage time (p<0.05). Immediately after freezing, the hardness of the control was higher than all treated samples, however it was lower after 1.5 and 3 months of frozen storage (p<0.05). The cohesiveness and gumminess of the control were higher than all treated samples immediately after freezing, however the values for T3 were higher than those of the control and the other two treatments during frozen storage for 1.5 and 3 months (p<0.05).

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.109-115
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• 2013

Glass bottle lightness index has been used as a guideline for the lightness of glass bottle. In this study, we developed a glass bottle lightness index (L) by modifying Emhart's lightness index. Domestic and foreign glass bottle products were collected in Korean market and classified into two groups, returnable bottle and one way glass bottle. Emptied glass bottle weight and volume were measured and written product's content volume were recorded to calculate the L value. Based on L value, 'acceptable' and 'optimum' criteria for design guideline of glass bottle were established for both returnable and one way glass bottles. Many of one way glass bottles failed to meet acceptable criteria (L=1.0), while returnable glass bottles mostly satisfied acceptable range (L=1.4). Few of one way glass bottles were even heavier than returnable glass bottles. Generally lightness index (L) of small size drink glass bottles (100 ml) were above 1.0, while these of juice glass bottles (180 ml) were close to acceptable criteria. Most foreign sauce glass bottles met the acceptable level, however most domestic souse glass bottles failed to satisfy acceptable criteria. A few foreign beer glass bottles satisfied optimum criteria, while most domestic beer glass bottles were acceptable level. Our results reveal that domestic glass bottles are mostly heavier than foreign glass bottles. In this paper, we suggest the use glass bottle lightness index as a design guideline for material resource reduction of glass bottle for Korean food and beverage industries.

• Analytical Science and Technology
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• v.29 no.2
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• pp.73-78
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• 2016

Hydrogen cyanide (HCN) is an extremely toxic gas frequently produced during the incineration of plastics, such as acrylonitrile-butadiene-styrene (ABS). A victim of a fire who has inhaled smoke could have cyanide in the blood. Therefore, cyanide could be a good marker for a post-mortem examination of a fire as well as carboxyhemoglobine (COHb) test of blood samples. For a particular fire case, a burned body with a suicide note was found inside a burned vehicle. Even though the COHb value is conclusive evidence, measuring the COHb for denatured blood might be difficult due to severe thermal denaturation or the formation of methemoglobin (MetHb). To overcome this difficulty, cyanide could be used as an indicator when investigating the death of a fire victim. In this study, gas chromatography/mass spectrometry (GC/MS) was adopted to measure the levels of cyanide in the blood through derivatization with pentafluorobenzyl bromide (PFBBr) under cation surfactant by scan and SIM mode. The concentration of cyanide in the blood of heart blood and brain of the victim was found to be 0.36 µg/mL and 1.20 µg/mL respectively, which was higher than the average value (0.041 µg/mL) found in the blood of 14 people who smoked.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.3
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• pp.391-400
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• 2001

In this paper, the performance of a multicarrier CDMA system applying M-ary orthogonal signaling and adaptive subchannel allocation scheme is analyzed for forward links in Rayleigh fading channel. Also, the effect of error caused by subchannel allocation is analyzed. In the proposed system, each DS waveform is transmitted over the subchannel having the biggest fading among L subchannels. Considering M-ary orthogonal signaling and 4 subchannels, the BER of $10^{-3}$ is satisfied if SNRs are 7.33 dB, 5.33 dB, and 4.47 dB for k = 1, 2, and 3, respectively. Therefore, SNR is decreased as k is increased. If the error of subchannels exists, the BER of $10^{-3}$ is met if SNR is 8.18 dB in the absence of M-ary orthogonal signaling. So, a required SNR is declined about 0.85 dB. Adding the M-ary orthogonal signaling with k = 4, it is observed that the multicarrier CDMA system has performance improvement because a required SNR is 5.44 dB.