• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.59 no.3
• /
• pp.275-288
• /
• 2010

In order to improve the quality of electricity in large scale power systems, stability of power system has to be achieved. This can be done by the means of preventative diagnosis of power equipments and protection, monitoring and control of the power system. Since the recent adoption of digital controllers, an improvement in stability was observed; in particular, IED, which contained self-diagnostic abilities such as fault tolerance, allowed for automatic recovery via redundancy or switching-over functions should there be faults with the equipments. Furthermore, communication lines have been hugely simplified, thus adding to the improvement in stability significantly. Taking these error reports and forecasting emergency reports and by effectively responding to them in the overiding controlling systems, high levels of system stability can be obtained. Power Management System that is being applied to automated power sub-stations, takes the IEC61850 international standard as its specification. In this paper, additional research into achieving stability of already developed PMS system and also the stability of the overall system was carried out, and the results of development of communication servers, which play a pivotal role in connecting systems, are stated.

• Tuberculosis and Respiratory Diseases
• /
• v.38 no.1
• /
• pp.70-73
• /
• 1991

We have experienced a case of lung injury caused by accidental inhalation of ammonia gas in a 34 year-old-man. By the explosion of ammonia tank in a refrigerator boat he inhaled ammonia gas. Several minutes later, he suffered from severe dyspnea and visual loss. On arrival at emergency room, analysis of arterial blood gas revealed severe hypoxemia and his chest film showed bilateral pulmonary infiltrates. Under the impression of adult respiratory distress syndrome, mechanical ventilator was applied to the patient. After recovery from ARDS and tracheal edema, he complained of some hemoptysis and productive sputum during the admission. So we checked bronchoscopy and bronchograpy which showed tracheal bullae just above carina and tubular bronchiectatic change in the right lower lobe. We report a case of lung injuries-ARDS, tracheal bullae, and bronchiectasis-caused by inhalation of ammonia gas with the review of the relevant literatures.

• Journal of Korean Neurosurgical Society
• /
• v.39 no.4
• /
• pp.277-280
• /
• 2006

Objective : The aim of this study is to determine which patients with progressively deteriorating acute cerebellar infarction would benefit from surgical treatment and which surgical procedure would best benefit them. Methods : Seventy six patients were treated at our hospital for cerebellar infarction over the past 3 years. Sixty nine patients received conservative management in the neurological department of our hospital. Among them, 7 patients [5 males and 2 females; average age, 49 yrs] were referred to neurosurgical department because of mental deterioration and underwent emergency surgery. Five patients underwent external ventricular drainage with suboccipital craniectomy and two patients underwent suboccipital craniectomy alone. Results : Of the 7 surgically treated patients, 4 patients experienced good recovery and 2 patients experienced moderate disability [disabled but independent] and 1 patient experienced severe disability [conscious but disabled]. There was no death. Conclusion : In patients conservatively treated for cerebellar infarction and showing mental deterioration and radiologically evident brainstem compression and ventricular enlargement, we strongly recommend suboccipital craniectomy [plus optional external ventricular drainage in case of showing hydrocephalus] as a first treatment option.

• Childhood Kidney Diseases
• /
• v.23 no.2
• /
• pp.116-120
• /
• 2019

Bilateral renal obstruction is a rare critical condition, requiring a prompt diagnostic approach and treatment to restore the renal function. The most commonly observed obstructive uropathy in children is congenital malformation, such as posterior urethral valves and bilateral ureteropelvic junction obstruction. Malignant pelvic masses obstructing the ureter are widely reported in adults but are rarely observed in children. The treatment of ureteral obstruction related to pelvic malignancy is a therapeutic challenge with a median survival duration of 3-7 months in adults; however, pediatric patients with pelvic malignancy leading to ureteral obstruction had better outcomes, with a reported 5-year mortality rate of 20%, than the adult patients. Here, we report a rare case of bilateral ureteral obstruction associated with pelvic rhabdomyosarcoma presenting with acute kidney injury treated by ureteral diversion with double J stent, and concommittent emergency hemodialysis, leading to restoration of good renal function. We suggest that bilateral ureteral obstruction should be released as soon as possible using surgical or interventional approach to minimize the obstruction period, and subsequential chemotherapy may contribute to improvement of survival and recovery of renal function.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.4
• /
• pp.673-685
• /
• 2021

This study aims to determine theoretically the best workers layoff/training strategy that entrepreneurs should apply to manage the COVID-19 crisis successfully. It also examines the impacts of the Saudi government's emergency measures on firm performance. The paper develops a theoretical framework in which the optimal control technics is applied to model the entrepreneur's hiring, layoff, and training behaviors. The results show that, during the current COVID-19 pandemic, the entrepreneur should first lay off the less productive workers to reduce labor costs. As more and more inefficient workers quit and profit increases, the entrepreneur starts expanding his activity and training workers. In the long run, only the training activity allows the firm efficiency to grow at a constant rate. This finding suggests that the key to long-run economic recovery in Saudi Arabia will rely on training, innovation, and adaptability to the new digital environment. The paper also shows that the Saudi government initiative of covering 60% of salaries for the small- and medium-sized entrepreneurs during the COVID-19 pandemic will enhance training activities in small- and medium-sized enterprises and improve their efficiency in both the short and long run. This policy will also prevent Saudi entrepreneurs from laying off half of their staff.

• International Journal of Internet, Broadcasting and Communication
• /
• v.13 no.1
• /
• pp.229-237
• /
• 2021

This study aimed to help build a quality control program to improve cardiac arrest treatment via analysis of medical records in a local tertiary general hospital to evaluate factors that influence clinical outcomes of in-hospital cardiac arrest. At first, the medical records of in-hospital cardiac arrest were analyzed, and targeted surveys about functional and structural factors associated with cardiopulmonary resuscitation (CPR) were conducted amongst the workforce in charge of cardiac arrest treatment. From January 2012 through June 2013, a total of 486 adult cases of in-hospital cardiac arrests, except for those occurring in the emergency room, were enrolled in this study. Among the patients, those of recovery of spontaneous circulation were 57.8%; 13.8% of patients were discharged alive; 8.9% of patients were discharged without significant neurologic sequela. Despite CPR is usually successful when administered as quickly as possible, in this analysis showed that prompt reaction after initial recognition was significantly lower in nurses compared with doctors. Analysis of survey results showed that confidence in performing CPR was significantly associated with the experience of CPR in doctors, while in nurses educational experience showed a correlation. In order to improve quality of in-hospital CPR system maintaining and increasing confidence of CPR performance is the most important factor. Therefore it can be helpful to develop and apply a phased, customized education program using training simulators as well as personalizing them to increase the personnel's confidence in CPR performance.

• Journal of the Korean Society of Safety
• /
• v.38 no.1
• /
• pp.18-24
• /
• 2023

Severe natural disasters and man-made attacks such as terrorism are causing unprecedented disruptions in power systems. Due to rapid climate change and the aging of energy infrastructure, both the frequency of failure and the level of damage are expected to increase. Resilience is a concept proposed to respond to extreme disaster events that have a low probability of occurrence but cause enormous damage and is defined as the ability of a system to recover to its original function after a disaster. Resilience is a comprehensive indicator that can include system performance before and after a disaster and focuses on preparing for all possible disaster scenarios and having quick and efficient recovery actions after an incident. Various studies have been conducted to evaluate resilience, but studies on economic damage considering the duration of a power outage are scarce. In this study, we propose an optimal algorithm that can identify failures after an extreme disaster and restore the load on the distribution system through emergency distributed power generation input and system reconfiguration. After that, the cost of power outage damage is analyzed by applying VoLL and CDF according to each restoration strategy.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.40 no.4
• /
• pp.429-435
• /
• 2020

North Korea declared itself complete with nuclear force after its sixth nuclear test in 2017. Despite efforts at home and abroad to denuclearize the Korean Peninsula, the prospects for the denuclearization are not bright. Along with political and diplomatic efforts to deter NK's WMD threats, the government is required to strengthen its consequence management capabilities against 'catastrophic situations' expected in case of emergency. Accordingly, this study was conducted to present measures to strengthen follow-up management against CBRN threats. The research model was partially supplemented and utilized by the THIRA process adopted and utilized by the U.S. Department of Homeland Security among national-level disaster management plan development models. Korea's consequence management (CM) system encompasses risk and crisis management on disaster condition. The system has been carried out in the form of a civil, government and military integrated defense operations for the purpose of curbing the spread or use of CBRNs, responding to threats, and minimizing expected damages. The preventive stage call for the incorporation of CBRN concept and CM procedures into the national management system, supplementing the integrated alarm systems, preparation of evacuation facilities, and establishment of the integrated training systems. In the preparation phase, readjustment of relevant laws and manuals, maintenance of government organizations, developing performance procedures, establishing the on-site support systems, and regular training are essential. In the response phase, normal operations of the medical support system for first aid and relief, installation and operation of facilities for decontamination, and development of regional damage assessment and control guidelines are important. In the recovery phase, development of stabilization evaluation criteria and procedures, securing and operation of resources needed for damage recovery, and strengthening of regional damage recovery capabilities linked to local defense forces, reserve forces and civil defense committees are required.

• Korean Journal of Clinical Pharmacy
• /
• v.29 no.3
• /
• pp.166-172
• /
• 2019

Background: Hypercalcemia is an important metabolic emergency condition in cancer patients. Bisphosphonate is the treatment of choice for hypercalcemia, whereas calcitonin and hydration with furosemide are recommended for acute supportive therapy. However, data regarding real-world treatment patterns and outcomes of pharmacological treatments are limited. Therefore, we aimed to investigate the treatment patterns and clinical outcomes of hypercalcemia treatment in solid tumor patients. Methods: Electronic medical records of 123 adults with solid cancers and albumin-corrected calcium levels >10.5 mg/dL or ionized calcium levels >1.35 mmol/L were reviewed. We retrospectively analyzed the pharmacological treatment and recovery rate according to the severity of hypercalcemia. Results: A total of 177 cases were identified, of which 49 were not treated and 30 were treated with hydration only. In moderate-to-severe cases, 86.5% received pharmacological treatment. Thirty-four cases (19.2%) were treated with bisphosphonate alone and 58 cases (32.8%) were treated with bisphosphonate and calcitonin. In mild hypercalcemia cases, the recovery rate was higher for those receiving hydration only or pharmacological treatment (79.7%) than for those receiving no treatment (61.4%, p = 0.041). Most moderate-to-severe cases were treated with medication and of those treated, 56.3% recovered. The recovery rate was lower in those treated with bisphosphonate alone (38.2%) than in those who underwent calcitonin combination treatment (73.7%, p = 0.001). Conclusions: Bisphosphonate combined with calcitonin was found to be more effective than bisphosphonate alone for the treatment of moderate-to-severe hypercalcemia. Considering the current shortage of calcitonin, further efforts are required to ensure its stable supply.

• Journal of the Society of Disaster Information
• /
• v.16 no.3
• /
• pp.449-457
• /
• 2020

Purpose: The Seoul Metropolitan Government classifies the cavity risks into emergency, priority, general, and observation grades in consideration of the cavity size, asphalt pavement thickness, and pavement depth based on the cavity management grade criteria of Seoul. In this study, the depth of cracking was measured at 17 cracks identified by checking the pavement condition of the cavity at 265 cavities found in the 2019 cavity investigation service. Method: In the first phase, crack width and depth were measured using a vernier caliper, taper gauge, and depth gauge to check the cracks of the identified cavities. In the second phase, the location of the largest crack in the upper road surface was confirmed, and A.C. was drilled to further measure the crack depth. Results: As a result, the cavity management level was raised in nine of the 17 test cavity identified. Therefore, in case of emergency and priority recovery, the grade should be adjusted according to the depth of pavement crack and the thickness of residual A.C. pavement. Conclusion: In the case of cracks in the upper part of the cavity, the crack progression must be determined through the perforation and the remaining asphalt concrete thickness must be determined to determine the cavity grade.