• Journal of Broadcast Engineering
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• v.15 no.2
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• pp.205-216
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• 2010

In this paper, a method of MPEG-2 Transport Stream (TS) multiplexing for Ultra HDTV (UHDTV) and its design and implementation as a SW tool is described. In practice, UHD video may be divided into several HD videos and each video is encoded in parallel. Therefore, it is necessary to synchronize and multiplex multiple bitstreams encoding each HD video for transmitting and storing UHD video. In this paper, it is assumed that 4 HD videos partitioning a UHD spatially are encoded as H.264/AVC and two 5.0 channel audios are encoded by AC-3. Therefore, 4 H.264/AVC elementary streams (ESs) and 2 AC-3 ESs is mainly considered in the TS multiplexing of UHD. For the carriage of H.264/AVC and AC-3 over MPEG-2 TS, PES packetization and TS multiplexing are designed and implemented based on the extended specification of the MPEG-2 Systems and ATSC (Digital audio compressed standard), respectively. The implemented UHD TS multiplexing tool emulates real time HW operation in the time unit corresponding to the duration of one TS packet transmission in a given TS rate. In particular, in order to satisfy the timing model, the buffers defined in the TS System Target Decoder (T-STD) are monitored and their statuses are considered in the scheduling of TS multiplexing. For UHD multiplexing, two kinds of multiplexing structures, which are UHD re-multiplexing and UHD program multiplexing, are implemented and their strength and weakness are investigated. The developed UHD TS multiplexing tool is tested and verified in terms of the syntax and semantics conformance and functionalities by using a commercial analyzer and real-time presentation tools.

• Journal of Digital Contents Society
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• v.19 no.7
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• pp.1365-1372
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• 2018

The purpose of this study is to analyze the importance of the determinants of housing sales agency's role in the sale of apartment housing. For this purpose, a hierarchical decision model was constructed to understand the role and importance of the sales agency. The analytical variable items structured by the research model were set up through literature review, precedent research, and expert brainstorming. The questionnaire consisted of two comparisons for AHP analysis and the importance of absolute importance for fuzzy analysis. Afterwards, the work of correcting the importance was carried out. As a result of the analysis, it was found that the contractor prioritized the sale conditions and the sales agency had priority over the planning for the sale. As a result of analysis, planning of customer pre-sale counseling data, planning of client subscription and contract maximization plan, planning method of advertisement public media method were found to be the most important factors. The results of measurement of absolute importance(fuzzy) & relative importance(,AHP) showed similar tendency. Therefore, it can be seen that the timing of the model house operation is an important period in which the subscription rate depends on the role of the sales agency and the marketing strategy.

• Journal of Gastric Cancer
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• v.7 no.1
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• pp.23-30
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• 2007

Purpose: Evaluating the clinicopathologic characteristics of recurred gastric cancer is essential for early detection of the recurrence and for better clinical outcome. The aim of this study was to establish the patterns of the recurrence, the timing of the recurrence, and the clinical result after recurrence according to the clinicopathologic characteristics of gastric cancer. Materials and Methods: From June 1992 to December 2005, of the 1338 gastric cancer patients who underwent a curative gastric resection, 241 patients who recurred during the follow-up period were selected and their cases were analyzed. The clinicopathologic characteristics of the patients, the time to recurrence after operation and survival were determined retrospectively according to the type of recurrence. Results: For the recurrent group, the numbers of total gastrectomies, advanced stages, lymphatic and/or venous infiltrations, whole stomach cancer cases, large tumors, undifferentiated tumors, and Borrmann type 4 tumors were higher than they were for the non-recurrent group, and the differences were statistically significant. When the recurrence types were classified as peritoneal seeding, hematogenous recurrence, and locoregional recurrence, independent risk factors were female gender, stage III, upper third, and whlole stomach cancer, and undifferentiated- type, diffuse-type, and Borrmann type 4 tumors for peritoneal seeding; early gastric cancer, stage I for hematogenous recurrence; and Borrmann type 1, 2, and 3 tumors for locoregional recurrence. Survival duration after detection of the recurrence was shorter for peritoneal seeding than for hematogenous or locoregional recurrence (7.0 months vs. 9.5 months and 12.5 months). Conclusion: For early detection of the recurrence after curative surgery for gastric cancer, it is important to recognize that the high risk factors for recurrence vary with the clinicopathologic data for the patients.

• The KIPS Transactions:PartA
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• v.11A no.2
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• pp.195-202
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• 2004

This paper introduces the design or parallel Pipeline high-speed analog-to-digital converter(ADC) for the high-resolution video applications which require very precise sampling. The overall architecture of the ADC consists of 4-channel parallel time-interleaved 10-bit pipeline ADC structure a]lowing 200MSample/s sampling speed which corresponds to 4-times improvement in sampling speed per channel. Key building blocks are composed of the front-end sample-and-hold amplifier(SHA), the dynamic comparator and the 2-stage full differential operational amplifier. The 1-bit DAC, comparator and gain-2 amplifier are used internally in each stage and they were integrated into single switched capacitor architecture allowing high speed operation as well as low power consumption. In this work, the gain of operational amplifier was enhanced significantly using negative resistance element. In the ADC, a delay line Is designed for each stage using D-flip flops to align the bit signals and minimize the timing error in the conversion. The converter has the power dissipation of 280㎽ at 3.3V power supply. Measured performance includes DNL and INL of +0.7/-0.6LSB, +0.9/-0.3LSB.

• Journal of Service Research and Studies
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• v.10 no.3
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• pp.81-101
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• 2020

Humanity has reached the age of service economy. A new economy requires new management. The chief executive of new management is the CEO. The results of management decision-making are reflected in the company's performance, and are the basis for future growth engines. This study empirically analyzed the effect of CEO competence, corporate orientation, and management performance of small and medium-sized mid-sized business managers on each other. In the study, a hypothesis was established between eight variables. In addition, the relationship between corporate orientation and CEO competency, which has not been studied, was also identified. Set personal effectiveness, willingness to innovate, opportunity recognition, information perception, relationship formation, business management, leadership, organizational culture, and human resource management as measures of CEO competency. After defining the operation in accordance with this study, the analysis was conducted. As a result of the analysis, corporate orientation did not produce a meaningful result in management performance. And CEO competency showed a positive (+) effect on management performance. It can be judged that the CEO variable, a management variable, had a positive effect on management performance. Also, there was a significant result in the relationship between corporate orientation and CEO competency. Innovativeness, initiative, and risk-taking have positive implications for CEO competency. Lastly, corporate orientation showed statistically significant results on management performance through the mediation of CEO competency. It is worth noting the results of this study in that the time of the study was the timing of the global pandemic (fendermic) of the COVID19 virus. In the future, in-depth research is needed on the relationship between CEO-related factors and management performance in a more changed economic environment.

• Journal of Chest Surgery
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• v.44 no.5
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• pp.332-337
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• 2011

Background: The optimal timing of surgery for infective endocarditis complicated by embolic stroke is unclear. We compared early versus delayed surgery in these patients. Materials and Methods: Between 1992 and 2007, 56 consecutive patients underwent open cardiac surgery for the treatment of infective endocarditis complicated by acute septic embolic stroke, 34 within 2 weeks (early group) and 22 more than 2 weeks (delayed group) after the onset of stroke. Results: The mean age at time of surgery was $45.7{\pm}14.8$ years. Stroke was ischemic in 42 patients and hemorrhagic in 14. Patients in the early group were more likely to have highly mobile, large (>1 cm in diameter) vegetation and less likely to have hemorrhagic infarction than those in the delayed group. There were two (3.7%) intraoperative deaths, both in the early group and attributed to neurologic aggravation. Among the 54 survivors, 4 (7.1%), that is, 2 in each group, showed neurologic aggravation. During a median follow-up of 61.7 months (range, 0.4~170.4 months), there were 5 late deaths. Overall 5-year neurologic aggravation-free survival rates were $79.1{\pm}7.0%$ in the early group and $90.9{\pm}6.1%$ in the delayed group (p=0.113). Conclusion: Outcomes of early operation for infective endocarditis in stroke patients were similar to those of the conventional approach. Early surgical intervention may be preferable for patients at high risk of life-threatening septic embolism.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.17-28
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• 2009

There are many limitations in dealing with rapidly changing traffic demand in urban cities. Thus recently, traffic operation and management skills are more emphasized rather than the expansion of traffic facilities. In particular, in the interrupted flow formed by signalized intersections, it is quite important to give optimal signal timing to each intersection with consideration of progression. However, as fixed signal times per direction can affect passing capacity in signalized intersections, the present four-signal phase including a left-turn signal has many limitations, including reduction of directional road capacity when traffic demand is increases dramatically during peak hours. Because of this problem, lots of studies about internal metering techniques for oversaturated signal control skills have progressed but these techniques are not used widely due to the absence of detectors for queue sensing in real-time signal control systems. In this research, a new methodology called the "restrictive left-turn signal control", which is already used at the intersection above Samsung subway station, is suggested in order to reduce control delay of urban arterial roads. The restrictive left-turn signal control allows a driver to make a U-turn and then a right turn instead of turning left in that intersection. With this change, the restrictive left-turn signal control can contribute to increased intersection capacity by reducing the number of signal phases and maximizing the through phase time. However, road structure and traffic conditions at the target intersections should be considered before the adoption of the proposed signal control.

• Journal of the Korea Society of Computer and Information
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• v.27 no.2
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• pp.125-134
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• 2022

In this paper, we propose an extension method of the BR2K technique for enhancing the robustness of blockchain application services. The BR2K (Blockchain application, Replication & Recovery technique using Kubernetes) technique was recently developed to support the robustness of blockchain services through service replication and rapid restart. The proposed technique extends the existing BR2K technique to provide a state version, which is meta-information about the service state, and a method for safely managing it, and use the state version to determine the timing for service state recovery. Also, the technique provides systematic service state backup for service recovery and joining of new service nodes by utilizing the version information and the service registry which acts as a service recovery center in the BR2K technique. Based on this, it is possible to support new service nodes to join the replication service with consistency. As a result, new service nodes can be quickly added to the BR2K service in operation, enhancing the robustness of the BR2K service. In addition, the extended method is applied to the pilot blockchain application service and tested in a Kubernetes environment composed of virtual machines to confirm the validity of service replication consistency and rapid service recovery in the event of node failures.

• Journal of Practical Engineering Education
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• v.15 no.3
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• pp.751-759
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• 2023

In the era of global aging and the retirement of baby boomers, the response is very intensive and dynamic. As baby boomers actually retire, the terms for middle-aged people have been diversified into middle-aged, midle-elderly, and the new middle, which are also evident in the training process. In line with the timing, the government and academia are also making efforts to advance the development of training courses for middle-aged, along with organizing terms for middle-aged. From this point of view, this study aims to analyze the performance of the three-year training courses (2018-2020) for the new middle at Korea Polytechnics and suggest the direction of development of the new middle training course. As a result of the study, the three-year performance of the Shin middle-aged training course gradually increased, but the completion rate and employment rate gradually decreased, indicating that countermeasures were needed. In addition, campus performance in the metropolitan area was higher than that in the non-capital area, so a plan for this deviation was needed. In addition, the need for the integrated operation of the existing 'middle-aged' and 'the new middle' courses operated by Korea Polytechnics was suggested, and measures to specialize in the new middle-aged were proposed.

• Journal of Korean Neurosurgical Society
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• v.30 no.6
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• pp.705-710
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• 2001

Objective : Postoperative seizure is a well documented complication of aneurysm surgery. The purpose of the present study was to analyze risk factors for postoperative seizure. Methods : Between January 1990 and December 1996, we performed craniotomy for ruptured cerebral aneurysms in 321 patients. Among them 206 patients who could be followed up for more than 1 year(range, 1 to 4.6 years) were enrolled to present study. All patients were treated with anticonvulsants for 3 to 18 months postoperatively. We analyze the incidence of postoperative seizure in different sex and age groups, and risk factors associated with postoperative seizures following aneurysm rupture. For statistical processing chi-square test and Fisher's exact test were used. Results : In the follow-up period of 1 to 4.6 years(mean, 1.8 years) postoperative seizure appeared in 18 out of 206 patients(8.7%). Mean latency between the operation and the first seizure was 6 months(range, 3 weeks to 18 months). The age of the patients has significant influence on the risk of seizure, it occurred more often in younger patients(p =0.0014). Aneurysm location in the MCA was associated with a significantly a higher risk of seizure(p = 0.042). Eight patients(19%) out of 42 patients who suffered delayed ischemic neurologic deficit(DID) developed seizure. Delayed ischemic neurologic deficit was associated with significantly a higher risk of seizure(p =0.019). Infarct and hypertension were associated with significantly a higher risk of seizure(p <0.05). pre- or postoperative intracranial hematoma(intracerebral or epidural hematoma) was associated with significantly a higher risk of seizure(p <0.0001). H-H grade, Fisher grade, Glasgow Outcome Scale of patients and timing of operation after subarachnoid hemorrhage had no significant relation with the risk of seizure. Conclusion : Factors associated with the development of postoperative seizure were middle cerebral artery aneurysm, delayed ischemic neurologic deficit, infarct on late postoperative CT scan, hypertension, pre or postoperative intracranial hematoma(intracerebral or epidural hematoma). Identification of the risk factors may be help to focus the antiepileptic drug threapy in cases prone to develop seizures. Prospective evaluation is indicated.