• The Journal of the Korea Contents Association
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• v.5 no.3
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• pp.193-199
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• 2005

One of the important fields for heuristics algorithm is how to balance between Intensificationand Diversification. Ant Colony System(ACS) is a new meta heuristics algorithm to solve hard combinatorial optimization problem. It is a population based approach that uses exploitation of positive feedback as well as greedy search. It was first proposed for tackling the well known Traveling Salesman Problem(TSP). In this paper, we propose Multi Colony Interaction Ant Model that achieves positive negative interaction through elite strategy divided by intensification strategy and diversification strategy to improve the performance of original ACS. And, we apply multi colony interaction ant model by this proposed elite strategy to TSP and compares with original ACS method for the performance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.1
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• pp.61-66
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• 2001

In this paper, we design high speed Viterbi decoding algorithm which is aimed for Wireless LAN. Wireless LAN transmits data at rate 6∼54 Mbps. This high speed is not easy to implement Viterbi decoder with single ACS. So parallel ACS butterfly structure is to be used and several time-dependent problem is to be solved. We simulate Viterbi algorithm using new branch metric calculating method to save time, and consider trace back algorithm which is adaptable to high speed Viterbi decoder. With simulated, we determine the structure of Viterbi decoder. This architecture is available to high speed and low power Viterbi decoder.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.473-477
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• 2012

The novel chitosan-based thermosensitive hydrogels were prepared as control-releasing drug carriers. N-carboxyethyl chitosan (ACS) was synthesized by microwave heating for 1 h through Michael addition of CS to acrylic acid in a grafting yield of 52.97%, which was proved to be a faster and more efficient way than ordinary methods. 5-Fu was modified with formaldehyde to synthesize N,N'-Bis(hydroxymethyl)-5-fluorouracil (5-Fu-OH). Then an esterification was performed using ACS and 5-Fu-OH to give 5-Fu-ACS. The new thermosensitive hydrogels were prepared by adding sodium glycerophosphate to the solution of compounds under a certain constant temperature. Simultaneously, the hydrogels' swelling rate, in vitro drug release rate and thermosensitive were studied, and found that the 5-Fu-ACS composite hydrogel had more excellent releasing effect, higher drug loading and better thermosensitive.

• The KIPS Transactions:PartB
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• v.13B no.3 s.106
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• pp.315-322
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• 2006

Ant Colony System(ACS) is easily applicable to the traveling salesman problem(TSP) and it has demonstrated good performance on TSP. Recently, ACS has been emerged as the useful tool for the pattern recognition, feature extraction, and edge detection. The edge detection is wifely utilized in the area of document analysis, character recognition, and face recognition. However, the conventional operator-based edge detection approaches require additional postprocessing steps for the application. In the present study, in order to overcome this shortcoming, we have proposed the new ACS-based edge detection algorithm. The experimental results indicate that this proposed algorithm has the excellent performance in terms of robustness and flexibility.

• The Korean Journal of Pain
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• v.7 no.2
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• pp.199-204
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• 1994

The purpose of this study is to evaluate the feasibility, advantages/disadvantages of patient-controlled sedation (PCS) compared to anesthesiologist-controlled sedation (ACS) during neurolytic pain block and regional anesthesia. Forty patients were divided randomly into two groups of 20 patients each. Group 1(ACS) received 0.01 $mg{\cdot}kg^{-1}$ intravenous midazolam and 0.5 ${\mu}g{\cdot}kg^{-1}$ fentanyl intravenously by anesthesiologist just before, 30, and 60 minutes after the procedure to acheive sedation; Group 2 (PCS) patients self-administered a mixture of midazolam (0.4 mg) and fentanyl ($20{\mu}g$) using a syringe type infusion pump (Terumo, Japan) to acheive sedation. Considering the dermographics of patients, the types and durations of procedure performed, the level of average sedation the comfort level were similar in both groups. But the doses of midazolam and fentanyl administerd in group 2 were smaller than those in group 1 (p<0.01). Patients in PCS group showed their level of sedation more proper than did those in ACS group. However, patients in ACS group rated their level of comfort higher than did those in PCS group. The findings of this study indicate that PCS using a combination of midazolam and fentanyl is a fafe and effective technique. More studies are, however, needed to determinc the best choice of drug(s), doses, lock-out intervals, and possible use of continuous infusion with patient-controlled sedation.

• Korean Journal of Clinical Pharmacy
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• v.20 no.1
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• pp.85-87
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• 2010

Recently, the prevalence of bladder cancer is increasing in the Korean society. As the risk factors of bladder carcinoma are variable, the early-stage diagnosis is regarded the best preventive practice. Hematuria is a specific sign of the malignancy as well as a kind of various medication-related adverse reactions. Some anti-coagulation therapy can cause bleedings including hematuria to the patients with cardiovascular diseases such as paroxysmal atrial fibrillation (PAF). Therefore, to the clinical pharmacists working in the anti-coagulation services (ACS), a closer monitoring of patients can give an opportunity to find certain ailments unexpectedly. In this case, a patient with PAF had episodes of sporadic hematuria in the course of warfarin therapy even though with its low levels of INR. An ACS pharmacist found a discrepancy between the bleeding symptoms and INR values, and recommended properly the patient to refer urologist. Fortunately, an early-stage of bladder carcinoma was found then followed by an excision performed to the lesion. Therefore, alert-minded and precise monitoring done by ACS pharmacist could optimize the therapeutic outcomes as well as increase the quality of life of the patient.

• Carbon letters
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• v.4 no.1
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• pp.31-35
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• 2003

The specific adsorption behaviors of activated carbons (ACs) treated with 30 wt% $H_3PO_4$ or NaOH were investigated in the removals of NO or $NH_3$. The acid and base values were determined by Boehm's titration method. And, the surface properties of ACs were studied by FT-IR and XPS analyses. Also, $N_2/77K$ adsorption isotherm characteristics, including the specific surface area and micropore volume were studied by BET and t-plot methods, respectively. From the adsorption tests of NO and $NH_3$, it was revealed in the case of acidic treatment on ACs that the $NH_3$ removal was more effective due to the increase of acidic functional groups in carbon surfaces. Also, the NO removal was increased, in the case of basic treatment, due to the improvement of basic functional groups, in spite of significant decreases of BET's specific surface area and total pore volume. It was found that the adsorption capacity of ACs was not only determined by the textural characteristics but also correlated with the surface functional groups in the acid-base intermolecular interactions.

• Journal of Periodontal and Implant Science
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• v.45 no.6
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• pp.238-246
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• 2015

Purpose: The purpose of this study was to evaluate bone formation around recombinant human bone morphogenetic protein (rhBMP-2)-coated implants placed with or without absorbable collagen sponge (ACS) in rabbit maxillary sinuses. Methods: The Schneiderian membrane was elevated and an implant was placed in 24 sinuses in 12 rabbits. The space created beneath the elevated membrane was filled with either blood (n=6) or ACS (n=6). In the rabbits in which this space was filled with blood, rhBMP-2-coated and non-coated implants were alternately placed on different sides. The resulting groups were referred to as the BC and BN groups, respectively. The AC and AN groups were produced in ACS-grafted rabbits in the same manner. Radiographic and histomorphometric analyses were performed after eight weeks of healing. Results: In micro-computed tomography analysis, the total augmented volume and new bone volume were significantly greater in the ACS-grafted sinuses than in the blood-filled sinuses (P<0.05). The histometric analysis showed that the areas of new bone and bone-to-implant contact were significantly larger in the AC group than in the AN group (P<0.05). In contrast, none of the parameters differed significantly between the BC and BN groups. Conclusions: The results of this pilot study indicate that the insertion of ACS after elevating the Schneiderian membrane, simultaneously with implant placement, can significantly increase the volume of the augmentation. However, in the present study, the rhBMP-2 coating exhibited limited effectiveness in enhancing the quantity and quality of regenerated bone.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.396-400
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• 2010

In this work, the adsorption behaviors of activated carbons (ACs) containing chelating functional groups were studied in $CO_2$ removal. The ACs were modified by pyrolysis of peroxide and glycidyl methacrylate graft polymerization in order to induce chelating functional groups, such as diethylenetriamine groups on the AC surfaces. The surface functional groups of the ACs were characterized by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The textural properties of the ACs were analyzed by $N_2$/77 K isotherms. Adsorption behaviors of the ACs were observed in the amounts of $CO_2$ adsorption. From the results, we found that the chelating functional groups on the AC surfaces led to enhance selectivity and chemisorption on $CO_2$ adsorption in spite of decreasing the physical adsorption properties.

• Journal of Gastric Cancer
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• v.20 no.3
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• pp.267-276
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• 2020

Purpose: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) risk calculator is useful in predicting postoperative adverse events. However, its accuracy in specific disorders is unclear. We validated the ACS NSQIP risk calculator in patients with gastric cancer undergoing curative laparoscopic surgery. Materials and Methods: We included 207 consecutive early gastric cancer patients who underwent laparoscopic gastrectomy between January 2018 and January 2019. The preoperative characteristics and risks of the patients were reviewed and entered into the ACS NSQIP calculator. The estimated risks of postoperative outcomes were compared with the observed outcomes using C-statistics and Brier scores. Results: Most of the patients underwent distal gastrectomy with Roux-en-Y reconstruction (74.4%). We did not observe any cases of mortality, venous thromboembolism, urinary tract infection, renal failure, or cardiac complications. The other outcomes assessed were complications such as pneumonia, surgical site infections, any complications requiring re-operation or hospital readmission, the rates of discharge to nursing homes/rehabilitation centers, and the length of stay. All C-statistics were <0 and the highest was for pneumonia (0.65; 95% confidence interval: 0.58-0.71). Brier scores ranged from 0.01 for pneumonia to 0.155 for other complications. Overall, the risk calculator was inconsistent in predicting the outcomes. Conclusions: The ACS NSQIP surgical risk calculator showed low predictive ability for postoperative adverse events after laparoscopic gastrectomy for patients with early gastric cancer. Further research to adjust the risk calculator for these patients may improve its predictive ability.