• The KIPS Transactions:PartB
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• v.8B no.5
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• pp.523-532
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• 2001

A Critical issue in the performance of a video-on-demand system is the required I/O bandwidth of the Video server in order to satisfy clients requests, and it is the crucial resource that may cause delay increasingly. Several approaches such as batching and piggybacking are used to reduce the I/O demand on the video server through sharing. Bathing approach is to make single I/O request for storage server by grouping the requests for the same object. Piggybacking is th policy for altering display rates of requests in progress for the same object to merge their corresponding I/O streams into a single stream, and serve it as a group of merged requests. In this paper, we propose a reservation-based hybrid disk bandwidth reduction policy that dynamically reserves the I/O stream capacity of a video server for popular videos according to the loads of video server in order to schedule the requests for popular videos immediately. The performance of the proposed policy is evaluated through simulations, and is compared with that of bathing and piggybacking. As a result, we know that the reservation-based hybrid disk bandwidth reduction policy provides better probability of service, average waithing time and percentage of saving in frames than batching and piggybacking policy.

• Archives of Reconstructive Microsurgery
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• v.6 no.1
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• pp.96-102
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• 1997

The gracilis that is frequently used as a donor of free muscle trasfer is appropriate in the muscular shape and vascular position. This muscle is belonged to the second type of muscle group by the classification of the pattern of muscular nutrient vessel. The adductor branch or first perforating branch of deep femoral artery which supplies the proximal 1/3 of this muscle is a dominant one and this is used for the microscopic anastomosis of muscle or musculocutaneous flap. The minor vascular pedicles which enter the distal 1/3 of this of this muscle are branches of the superficial femoral artery and it is 0.5mm in diameter, 2cm in length with two venae comitantes. These minor pedicles supplies distal half of the gracilis muscle. This island musculocutaneous flap using distal vascular pedicle can be used to cover the defect of soft tissue around the distal femoral supra-condylar area, knee joint and proximal tibial condyle area which cause limitation of motion of knee joint, or in the cases that usual skin graft is impossible. The important operative procedure is as follows; The dissection is carried proximally and distally and the entire gracilis muscle including proximal and distal pedicle is completely dissected. After temporary blocking of the proximal vascular pedicle, the adequate muscle perfusion by the distal pedicle is identified and it is rotated to the recipient site around knee joint. The advantages of this procedure are simple, no need of microscopic vascular anastomoses and no significant functional loss of donor site. Especially in the cases of poor condition of the recipient vessel, this procedure can be used effectively. From 1991 to 1996, we performed 4 cases; complete survival of flap in 3 cases and partial survival of flap with partial necrosis in 1 case. This procedure is though to be useful in the small sized soft tissue defect of distal femoral supra-condylar area, knee joint and proximal tibial condylar area, especially in the defect of anterior aspect which expected to cause limitation of motion of knee joint due to scar contracture. But the problems of this procedure are the diameter of distal vascular pedicle is small and the location of distal vascular pedicle is not constant. To reduce the failure rate, identify the muscular perfusion of distal vascular pedicle after blocking the proximal pedicle, or strategic delay will be helpful.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7863-7867
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• 2014

Background: Retinoblastoma is a rare type of cancer that usually develops in early childhood. If left untreated it can cause blindness and even death. The aim of this study is to determine sociodemographic and clinical features of retinoblastoma patients and also to determine the treatment pattern and outcome in Malaysia. Materials and Methods: Data for this study were retrieved from the Retinoblastoma Registry of the National Eye Database (NED) in Malaysia. Hospital Kuala Lumpur, Hospital Umum Kuching, Sarawak and Hospital Queen Elizabeth, Kota Kinabalu were the major source data providers for this study. Data collected in the registry cover demography, clinical presentation, modes of treatment, outcomes and complications. Results: The study group consisted of 119 patients (162 eyes) diagnosed with retinoblastoma between 2004 and 2012. There were 68 male (57.1%) and 51 (42.9%) female. The median age at presentation was 22 months. A majority of patients were Malays (54.6%), followed by Chinese (18, 5%), Indians (8.4%), and indigenous races (15.9%). Seventy six (63.8%) patients had unilateral involvement whereas 43 patients had bilateral disease (36.1%). It was found that most children presented with leukocoria (110 patients), followed by strabismus (19), and protopsis (12). Among the 76 with unilateral involvement (76 eyes), enucleation was performed for a majority (79%). More than half of these patients had extraocular extension. Of the 40 who received chemotherapy, 95% were given drugs systemically. Furthermore, in 43 patients with bilateral involvement (86 eyes), 35 (41%) eyes were enucleated and 17 (49%) showed extraocular extension. Seventy-two percent of these patients received systemic chemotherapy. The patients were followed up 1 year after diagnosis, whereby 66 were found to be alive and 4 dead. Sixteen patients defaulted treatment and were lost to follow-up, whereas follow-up data were not available in 33 patients. Conclusions: Patients with retinoblastoma in this middle-income Asian setting are presenting at late stages. As a result, a high proportion of patients warrant aggressive management such as enucleation. We also showed that a high number of patients default follow-up. Therefore, reduction in refusal or delay to initial treatment, and follow-up should be emphasized in order to improve the survival rates of retinoblastoma in this part of the world.

• Korean Security Journal
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• no.1
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• pp.283-319
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• 1997

Our society witnesses the rapid progress in the areas of politics, economy, society and culture in the process of national modernization since 1960s, which in turn as a reverse function gets to contract a societic pathology, totally lowering the security level of citizens' lives owing to various violent crimes like hostage commotions and murders with rifles and deadly weapons. what is the main reason for that? That may be partly because the chief police force concentrates on the current situation resulting in the vacuum of the public peace. However, the main reason is that the police fall short of man-power and equipments even if the whole police power were put to use in preventing and quelling the crimes. That is true not only of Korea but also of the advanced countries like the U.S.A., England and Japan. We realize that these advanced countries have higher level of security in every individual's life and property than Korea because their progress of the private guard systems can fill in a vacuum of the shortage of the police power, Therefore, we should without delay internationalize our private guard systems expecting the widely opening of the guard service markets in the age of Uruguay Round. To do this, we need to change our ideas for fostering the policy of the private guard from passive defense ideas into positive aggressive ones. Our police should urgently set up a plan to pursue the orientation of vision that we should dispatch our private guards overseas before foreign guards rush into our markets. Accordingly it goes without saying that the private guard group should distinguish their services from the public services initiating their own theory and strategy of private guard services and also readjust themselves between the public duties and the private services with the study of minimizing the reverse function of the private guard systems. The history criminal justice has always shown that the criminal system progressed at the initiative of the civil factor in case its demand and supply do not make both ends meet. Nevertheless, in the process the power of the government never weakens, rather it is built up in general. In conclusion, the necessity of the build-up of the private guard services must duly be acknowledged by the police as well as by the business which has its unique sphere within the criminal justice instead of as the suplemtary services of the simple the police power on the long-term basis. The purpose of the private guard services can be largely classified into the two categories; first it means the function to prevent the crimes against the citizens and secondly to enhance the national interest as an increasing mammoth business with a worldly competition capacity. The police has an absolute responsibility that they should protect the modem public in general from feeling the crisis of the personal threat, tension, anxiety and nervousness. In short, if we develop the complete private guard system to guarantee the societic atmosphere for all citizens, keep the public peace, and protect all citizens' lives and properties, we will sure enjoy a beautiful land, a wholesome society and a happy life in goodharmony of law and order.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.1 s.343
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• pp.111-120
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• 2006

In this paper, a node architecture of WDM metro network for connecting broadband access networks to converge wire/wireless networks. In consideration of the proposed node architecture and network requirements we proposed and evaluated medium access control protocols. We review WDM related technologies of sub-carrier multiplexing and optical components in order to resolve the bottleneck between optical backbone networks md access networks, and a access node architecture sharing common wavelength is introduced. Source-stripping (SS) MAC protocol Is evaluated under the proposed functional node architecture. DS+IS (Destination-Stripping and Source-Stripping) and DS+IS (Destination-Stripping and Intermediate-Stripping) MAC protocols are described to increase the slot-reuse factor which is low on SS MAC protocol. The key function of new MAC protocols regards the optical switch module of proposed node architecture and helps intermediate or source access nodes for dropping slots to destinations of different wavelength group. Thus, slot-reuse factor increases as the MAC protocols reduce the unnecessary ring-rotation of transferred slots. We use a numerical analysis to expect bandwidth efficiency and maximum throughput by slot-reuse factor Throughput network simulation, the verification of throughput, queuing delay, and transmission fairness are compared among MAC protocols.

• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1024-1030
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• 1998

We investigated the effects of vitamin E supplementation on protein glycosylation in early and end stage product, and light microscopic studies were done on the renal glomeruli of KK-mice of various ages and various duration of diabetes. Weaned KK-mice were fed high fat diets containing 20% corn oil(wt/wt), and sacrificed at 4,6, and 9 months of age. The high vitamin E diet was a high fit diet supplemented with an excess amount of d1-$\alpha$-tocopheryl acetate (2080IU/kg diet). We measured Hemoglobin $A_{IC}$ (Hb $A_{IC}$) as a glycosylation early product, and renal collagen-linked fluorescence as a glycosylation end product. In the diabetic group, levels of Hb $A_{IC}$ were increased within 2 months after onset of diabetes and remained at a constant level for the duration of experiment. 5 months after onset of diabetes, renal collagen linked fluorescence(CLF) was markedly increased. A quantative, morphologically demonstratable, progressive thickening of the basement membrane and calcification occured in the diabetic KK-mice. There is a statiscally positive correlation between CLF and histologic grade of diabetic nephropathy. Hepatic vitamin E levels correlated with those of Hb $A_{IC}$, renal CLF, and renal calcification. Treatment with vitamin I did not modify the level of blood glucose. However, we observered a significant lowering of CLF and Hb $A_{IC}$ in diabetic mice. Supplementation of vitamin E was found to delay the progression of diabetic nephropathy. (forean J Nutrition 31(6) : 1024-1030, 1998)0, 1998)

• Journal of Preventive Medicine and Public Health
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• v.26 no.3 s.43
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• pp.400-411
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• 1993

The aim of this study is to analyze the variations among hospitals and hospital groups in resource use and procedures of diagnostic and therapeutic process, such as laboratory tests, radiologic examinations, tissue diagnosis, timing of surgery after admission, the time required for operation. The study was performed for five procedures including cesarean section (C/S), appendectomy, cholecystectomy, cataract extraction, and pediatric pneumonia. The 2,316 subjects were selected from medical insurance claims list, and from this list 413 cases were sampled for medical record review. The patterns of resource utilization and process of treatment were described according to hospitals and characteristics of hospital groups. The major results were as follows : 1. The numbers of laboratory and radiologic tests showed significant difference among hospitals and hospital groups. In case of hospital groups, we could find tendencies of more tests with increasing hospital bed size. 2. In general, the proportion of operative cases evaluated by tissue diagnosis postoperatively among all operations ranged from 28.3% to 100%. The proportion varied among hospital groups, of which general hospital A group(more than 15 specialty) showed the highest proportion. 3. Post-admission delay until operation and the time required for operative procedure were not invariable among hospitals and hospital groups. The duration of operation in tertiary hospitals was slightly shorter than general hospitals, with varying statistical significance. We could find that probably there were differences of quality among hospitals in some components of procedures, which suggested that the implementation of quality assurance activities would be mandatory. In this study, we simply described the patterns of resource utilization and some features of clinical process, with institution of the need for advanced studies with in-depth analyses for each component of diagnosis and treatment procedures.

• The Korean Journal of Nuclear Medicine
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• v.32 no.3
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• pp.276-289
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• 1998

Purpose: To evaluate dysphagia objectively and quantitatively, and to clarify the effect of neck position and viscosity changes in patients with aspiration and laryngeal penetration. Materials and Methods: We studied 35 patients with dysphagia and 21 normal controls using videofluoroscopy and scintigraphy. Videofluoroscopy was performed with barium with three different viscosity, and scintigraphy was done with water, yogurt, and steamed egg mixed with Tc-99m tin colloid. If aspiration was found during videofluoroscopic examination, patient's neck position was changed and study repeated. Videofluoroscopy was analyzed qualitatively. We calculated 7 quantitative parameters from scintigraphy. According to the videofluoroscopic findings, we divided patients into 3 subgroups; aspiration, laryngeal penetration, and no-aspiration group. Results: The result of videofluoroscopy revealed that the most common finding was the delay in triggering pharyngeal swallow. Pharyngeal transit time (PTT) and pharyngeal swallowing efficiency(PSE) in patients with aspiration were signifi-cantly different from other groups. After neck position change, aspiration could be reduced in all of 7 patients, and laryngeal penetration reduced by about 82%. PTT and PSE were also improved after position change. Aspiration and laryngeal penetration occurred more frequently in thin liquid swallowing than in thick liquid and solid swallowing. Conclusion: PTT and PSE were useful for the evaluation of dysphagia. Aspiration and laryngeal penetration could be reduced when appropriate position assumed. We could decrease the chance of aspiration by changing the patient diet consistency. Scintigraphy might be useful tool to quantitate and follow up these changes.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.2 s.117
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• pp.126-135
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• 2007

This paper proposes a new miniaturization method for a parallel coupled line filter with enhanced bandwidth characteristics. A previous method incorporated several advantages, such as size reduction through the use of only a small number of capacitors, in addition to grounding, suppression of harmonic characteristics, and improved skirt characteristics for the parallel coupled line filter, which is conventional in the field of RE filters due to its design and fabrication simplicity. However, the previous method also has disadvantages related to the bandwidth shrinkage of the miniaturized filters. In this paper, the amount of bandwidth shrinkage is analyzed in terms of the relationship between the loaded Q(quality factor) and the group delay of a resonator. Moreover, the reduction in the bandwidth is solved by a design with new design equations. To show the validity of the proposed method, a hairpin filter with a center frequency of 5.2 GHz and an fractional bandwidth(FBW) of 10% was scaled down to half its original dimension by the proposed method with the enhanced bandwidth characteristics. The measured result shows a high level of agreement with theoretical results.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.2
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• pp.265-274
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• 2011

In this paper, it is studied on wide radiating slot antenna's miniaturization for ultra wide-band(UWB) technologies and notch structure to prevent interference between UWB systems and existing wireless systems for using Wi-Fi service of IEEE standards 802.11 a/n. Proposed antenna that wide slot is decreased from $\lambda/2$ to $\lambda/4$ length of resonant frequency has decreased by 72 % compared with conventional antenna. And optimized T-shaped CPW-fed stub has satisfied UWB bandwidth for 3.0~11.8 GHz. Then, creating 2-order Hilbert curve slot line in the stub's patch area, 4.9~5.6 GHz that centered frequency is 5 GHz is eliminated. Finally, the designed antenna constructed on FR4-epoxy has $20{\times}15\;mm^2$ dimension. The measured results that are obtained return loss under -10 dB through 3.2~11.8 GHz without Wi-Fi bandwidth, a linear phase characteristic, a stable group delay, and omnidirectional radiation patterns are presented.