• The KIPS Transactions:PartA
• /
• v.8A no.4
• /
• pp.469-478
• /
• 2001

In the virtual memory system, page replacement policy exerts a great influence on the performance of demand paging. There are LRU(Least Recently Used) and LFU (Least Frequently Used) as the typical replacement policies. The LRU policy performs effectively in many cases and adapts well to the changing workloads compared to other policies. It however cannot distinguish well between frequently and infrequently referenced pages. The LFU policy requires that the page with the smallest reference count be replaced. Though it considers all the references in the past, it cannot discriminate between references that occurred far back in the past and the more recent ones. Thus, it cannot adapt well to the changing workload. In this paper, we first analyze memory reference patterns of eight applications. The patterns show that the recently referenced pages or the frequently referenced pages are accessed continuously as the case may be. So it is rather hard to optimize page replacement scheme by using just one of the LRU or LFU policy. This paper makes an attempt to combine the advantages of the two policies and proposes a new page replacement policy. In the proposed policy, paging list is divided into two lists (LRU and LFU lists). By keeping the two lists in recency and reference frequency order respectively, we try to restrain the highly referenced pages in the past from being replaced by the LRU policy. Results from trace-driven simulations show that there exists points on the spectrum at which the proposed policy performs better than the previously known policies for the workloads we considered. Especially, we can see that our policy outperforms the existing ones in such applications that have reference patterns of re-accessing the frequently referenced pages in the past after some time.

• Journal of radiological science and technology
• /
• v.28 no.2
• /
• pp.105-110
• /
• 2005

Background/Aim : Common bile duct (CBD) stones may cause jaundice, cholangitis, or pancreatitis. Extracorporeal shock wave lithotripsy (ESWL) may be needed whenever endoscopic procedure are failed to extract common bile duct stones. The aim of this study is to provide the standard for patient's best choice on ESWL for treatment of CBD stones resistant to endoscopic extraction. Materials and Methods : Fourty-six patients failed in endoscopic stone extraction including mechanical lithotripsy were treated by ESWL. In all patients, endoscopic sphincterotomy and nasobiliary drainage tube was done before ESWL using the ultrasonography for stone localization with a spark-gap type lithotriptor. Patients were sedated with an intravenous injection of 50 mg of Demerol. None were treated under general anesthesia. Results : Overall complete clearance rate of CBD stone was 89.1% (41/46). In 82.6% of the patients, the stones were extracted endoscopically after ESWL, and spontaneous passage was observed in 6.5%. In the clearance rate after ESWL, there were no noticeable differences with regard to number (single: 82.8%, two or three: 100%, more than three: 100%) and size of the stone (less than 33mm: 92.9%, 33 mm or larger: 83.3%), whereas there were significant differences with regard to the ratio of sum of long-axis length of the all stones to sum of long-axis length of the CBD excluding stone (1:2.4, 1:2.1) and diameter of the largest stone to diameter of CBD excluding stone (1:0.9, 1:0.4) for patients with complete clearance compared with those without. Conclusion : We propose that stones without the fragments are travelable sufficient space in CBD or extractable sufficient diameter of CBD regardless of stone size and number should be treated by other technique to prevent time and cost consuming, such as percutaneous transhepatic cholangioscopylithotomy.

• Journal of radiological science and technology
• /
• v.27 no.2
• /
• pp.29-33
• /
• 2004

Until early 1980s we have lived without thinking that radon ruins our health. But, scientists knew truth that radon radioactive danger is bedeviling on indoor that we live for a long time. Specially, interest about effect that get in danger and injury for Radon and human body is inactive in our country. Recently, with awareness for Radon contamination, We inform about importance and danger of Radon in some station of the Seoul subway, indoor air of school facilities and We had interest with measure and manages. Usually, Radon gas emitted in base of building enters into indoor through building floor split windage back among radon or indoor air of radon daughter nucleus contamination is increased. Therefore, indoor radon concentration rises as there are a lot of windages between number pipe of top and bottom and base that enter crack from estrangement of the done building floor, underground to indoor. Thus, Radon enters into indoor through architecture resources water as well as, kitchen natural gas for choice etc., but more than about 85% from earth's crust emit. Danger and injury of health by Radon and Radon daughter nucleus that is indicated for cause of lung cancer incerases content of uranium of soil rises specially from inside pit of High area and a mine, cave, hermetical space with house. Safe sub-officer of radon concentration can not know and danger always exists large or small during. So, Important thing reduces danger of lung cancer by lowering concentration of Radon within house and building. Therefore, is thought that need general house Radon concentration measurement, measured Radon concentration monthly using Sintillator radon monitor. Study finding appeared high all underground market 1 year than the ground, and the winter appeared high than the summer. Specially, month that pass over 4pCi in house that United States Environmental Protection Agency advises appeared in underground, and appeared and know Radon exposure gravity by 4 months during 12 months. Therefore, Thinking that establishment and regulation of norm and preparation of reduction countermeasure about Radon are pressing feels, and inform result that measure Radon concentration.

• Korean Journal of Remote Sensing
• /
• v.31 no.6
• /
• pp.501-512
• /
• 2015

Landfast sea ice (LFI) in Terra Nova Bay, East Antarctica where the Jangbogo Antarctic Research Station is located, has significant influences on marine ecosystem and the sailing of an icebreaker. Therefore, it is essential to analyze the spatio-temporal variation of the LFI in Terra Nova Bay. In this study, we chose interferometric pairs with the temporal baseline from 1 to 9 days out of a total of 62 COSMO-SkyMed synthetic aperture radar (SAR) images over Terra Nova Bay obtained from December 2010 to January 2012, and then constructed the coherence image of each pair. The LFI showed coherence values higher than 0.3 even in the interferometric SAR (InSAR) pairs of up to 9-days of temporal baseline. This was because the LFI was fixed at coastline and thus showed low temporal phase decorrelation. Based on the characteristics of the coherence on LFI, We defined the areas of LFI that show spatially homogeneous coherence values higher than 0.5. Pack ice (PI) and open water showed low coherence values due to large temporal phase decorreation caused by current and wind. Distinguishing PI from open water in the coherence images was difficult due to their similarly low coherence values. PI was identified in SAR amplitude images by investigating cracks on the ice. The extents of the LFI and PI were estimated from the coherence and SAR amplitude images and their temporal variations were analyzed. The extent of the LFI increased from March to July (maximum extent of $170.7km^2$) and decreased from October. The extent of the PI increased from February to May and decreased from May to July when the LFI increases dramatically. The extent of the LFI and air temperature showed an inverse correlation with a time lag of about 2 months, i.e., the extent of the LFI decreases after 2 months of the increase in the air temperature. Meanwhile the correlation between wind speed and the extent of the LFI was very low. This represents that the extent of LFI in Terra Nova Bay are influenced more by the air temperature than wind speed.

• Korean Security Journal
• /
• no.61
• /
• pp.109-135
• /
• 2019

The purpose of this study is to investigate the occupational diseases(the number of medical treatment) of fire officials by using time-series analysis. The results of the study are as follows. First, the average rates of the occupational diseases of fire officials were as follows: ① internal diseases were the highest at 9.24% in December, the lowest at 7.76% in February, ② otolaryngologic diseases were the highest at 9.29% in December, the lowest at 6.74% in August, ③ dermatological diseases were the highest at 10.03% in July, the lowest at 7.35% in January and February, ④ surgical diseases were the highest at 10.38% in November, the lowest at 5.62% in February, ⑤ orthopedic diseases were the highest at 9.69% in March, the lowest at 7.52% in November, ⑥ neurosurgical diseases were the highest at 9.33% in April, the lowest at 6.82% in February, ⑦ neurological diseases were the highest at 9.47% in December, the lowest at 7.06% in October, and ⑧ mental health diseases were the highest at 9.93% in December, the lowest at 6.51% in May. Second, the seasonal decomposition of the disease occurrence of fire officials were described by assigning seasonal factor(S), trend factor(T), circulation factor(C) and irregular factor(R): ① internal diseases were 1.075(S) × 189.355(T·C) × 1.174(R) = 238.975(F), ② otolaryngologic diseases were 1.023(S) × 69.605(T·C) × 1.040(R) = 74.000(F), ③ dermatological diseases were 1.002(S) × 73.088(T·C) × 0.874(R) = 64.000(F), ④ surgical diseases were 1.099(S) × 27.229(T·C) × 0.669(R) = 20.000(F), ⑤ orthopedic diseases were 1.115(S) × 73.182(T·C) × 1.213(R) = 99.000(F), ⑥ neurosurgical diseases were 0.993(S) × 27.836(T·C) × 1.303(R) = 36.000(F), ⑦ neurological diseases were 1.029(S) × 62.417(T·C) × 1.152(R) = 74.000(F), and ⑧ mental health diseases were 1.210(S) × 8.781(T·C) × 1.035(R) = 11.000(F).

• The Journal of Korean Physical Therapy
• /
• v.3 no.1
• /
• pp.9-37
• /
• 1991

The purpose of this . study is to examine the unsatisfactory factors of the physical therapists and to obtain the materials necessary to comply with these factors by analysing their service performance and job satisfaction, To accomplish these purposes, this study was carried out by using the questionnaires 206 physical therapists registered in the Korean Physical Therapists Association, for 35 days from January 7 to February 10, 1990. The result of this study is summarized as follows. 1. Of total respondents, the male accounted for 54.4 percent, while the female for 45.6 percent. Their age showed that 20s accounted for 65.0 percent, while the service period less than 3 years accounted for 66.5 percent. In addition, 63.6 percent of them served at the general clinics. 2. The general clinics caused the physical therapists to serve for 10 hours or more per day, where their therapy room located in the underground accounted for 41.3 percent. Their health diagnosis status indicated that nondiagnosis accounted for 63.2 percent. The number of the served patients fer a day showed that 20-30 accounted for 37.4 percent, while 30 persons or more for 25.7 percent. 53.4 percent of total subjects was unsatisfied with their duty quantity. And, the monthly salary indicated that 500,000 or less accounted for 72.3 percent. 3. The average marks by their job satisfaction factors indicated 4.42 for duty importance, 4.02 for recognization of specialized job, 3.98 for ability exercise, 1.99 for promotion possibility, 2.28 for reasonable salary, and 2.41 for welfare system, respectively, based on 5 full marks. 4. The summarized job satisfaction by factors indicated that the relation with the doctor accounted for 57.8 percent, the satisfaction status with the existing job for 53.4 percent, the ability development for 41.8 percent, respectively, and the salary for 10.2 percent. Then, the satisfaction by sex showed that the male was generally satisfied with the ability development (p<0.05), the relation with the doctor (p<0.01), and the satisfaction with the existing job, while the female was satisfied with the duty quantity(p<0.05), salary, and the situation guarantee (p<0.05). On the other hand, the satisfaction by age indicated that the subject of the lower age were satisfied with the ability development (p<0.01), the relation with the doctor(p<0.05), the salary, and the situation guarantee. Also, the satisfaction by the service section showed that the physical therapists serving at the general hospital were satisfied with the ability development (p<0.01), the duty quantity (p<0.01), the salary(p<0.01), the situation guarantee(p<0.01), and the satisfaction with the existing duty (p<0.05), while the physical therapists at the hospital and the rehabilitation center were unsatisfied with the salary (p<0.01). In addition, The satisfaction with the service period at the existing section indicated that the physical therapists less than 3 years were highly satisfied with the ability development, the relation with the doctor, the situation guarantee, and the existing duty(p<0.05), while the physical therapists more than 6 years tended to show the lower satisfaction, And the satisfaction with the monthly salary indicated that the higher the monthly salary, the higher the satisfaction with the relation to the doctor(p<0.05), the duty quantity(p<0.01), the salary(p<0.01), and the situation guarantee (p<0.01). 5. The correlation between general characteristics and job satisfaction factors indicated that the sex was directly correlated to the marital status (r=-0.442), while it was reversely correlated to the age (r=-0.564) , total career (r=-0.229), and the relation with the doctor (r=-0.233). Additionally, the age was directly correlated to the total carreer (r=-0.677), and the service period at the existing section (r=0.491), while the age was reversely correlated to the marital status (r=-0.678). Accordingly, the higher job satisfaction of the physical therapists was related to factors such as their duty importance, recognization of specialized occupation, ability exercise, autonomy, relation to colleagues, decision-making's consideration, and relation with the doctor, while the lower job satisfaction includes the opportunity of promotion, salary, welfare system, service time, duty quantity, and situation guarantee. For this reason, if the factors of the lower job satisfaction are solved, then it will be possible to encourage the motive of these physical therapists, and the acyivate their duties. More over, it is also possible to improve the medical service, Additionally, if the general physical therapy room in the hospital and in the public health center are established, more development should be accomplished in the physical therapy.

• Journal of Chest Surgery
• /
• v.34 no.6
• /
• pp.477-484
• /
• 2001

Background: Initial symptoms for esophageal perforation have not been clarified, but when there is no early diagnosis and proper treatment to follow immediately after the diagnosis, it is fatal for the patients. Therefore, this study attempted to discover the factors that influence the prognosis of esophageal perforation to contribute to the improvement of the treatment result. Material and Method: The subjects of this study are 32 patients who came to the hospital with esophageal perforation from October, 1984 to June, 2000. This study examined the items for clinical observation such as patients' sex, age, cause of the perforation, perforation site, the time spent until the beginning of the treatment, symptoms caused by the perforation and its complication, and treatment methods. This study tried to find out the relationship between the survival of patients and each item. Result: There were 24 male and 8 female patients and their mean age was 49.7+16.4. For the causes of perforation, there were 14 cases(43%) of iatrogenic perforation, which ranked first, caused by the medical instrument operation and surgical damage. As for the perforation sites, thoracic esophagus was the most common site(26 cases of 81.2%) and chest pain was the most frequent symptom. The complication caused by esophageal perforation showed the highest cases in the order of mediastinitis, empyema, sepsis and peritonitis. After the treatment, there were 23 cases of survival and 9 cases of mortality. The total mortality rate was 28.1% and the main causes of mortality were sepsis and acute respiratory distress syndrome(ARDS). As for the treatment, 8 cases(25.0%) treated the perforation successfully using conservative treatment only. As for the surgical treatment, there were 5 cases(15.6%) of cervical drainage, 7 cases (21.8%) of primary repair and 12 cases(37.5%) of esophageal reconstruction after performing an exclusion-diversion. There were 18 cases(56.2%) of complete treatment of esophageal perforation at its initial treatment and in 14 cases(43.8%) of treatment failure at its initial treatment, patients were completely cured in the next treatment stage or died during the treatment. The cases of perforation in thoracic esophagus, complication into severe mediastinitis or sepsis and the cases of failure at initial treatment showed a statistically significant mortality rate (p<0.05).

• Journal of Chest Surgery
• /
• v.32 no.3
• /
• pp.255-261
• /
• 1999

Background: Atrial fibrillation is one of the most prevalent of all arrhythmias and in up to 79% of the patients with mitral valve disease. This study examined whether the atrial fibrillation that occur in patients with mitral valve operation could be eliminated by a concommitant maze operation without cryoablation. Material and Method: From May 1997 to April 1998, 14 patients with atrial fibrillation associated with mitral valve disease underwent Maze III operation without cryoablation. Preoperatively there were 6 men and 8 women with an average age of 46.2${\pm}$10.7 years. Eleven patients had mitral stenosis, and three had mitral insufficiency. The associated heart diseases were aortic valve disease in 4, tricuspid valve regurgitation in 1 and ASD in 2. Using transthoracic echocardiography, the mean left atrial diameters was 54.7${\pm}$5.3 mm and thrombi were found in the left atrium of 2 patients. Postoperatively the ratio between the peak speed of the early filling wave and that of the atrial contraction wave (A/E ratio) was determined from transmitral flow measurement. Operations were mitral valve replacement in 13 including 4 aortic valve replacements, 1 DeVega annuloplasty and 2 ASD closures. Maze III operation was performed in 1 patient. Result: Five patients (38%) had recurred atrial fibrillation, which was reversed with flecainide or amiodarone at the average time of postoperative 38.8${\pm}$23.5 days. Postoperative complications were postoperative transient junctional rhythm in 6, transient atrial fibrillation in 5, reoperation for bleeding in 3, postpericardiotomy syndrome(1), unilateral vocal cord palsy(1), postoperative psychosis(1), and myocardial infarction(1). Postoperatively A/E ratio was 0.43${\pm}$0.22 and A wave found in 9(64%) patients. 3 to 14 months postoperatively (average follow- up, 8.1 months), all of patients had normal sinus rhythm and 9(64%) patients had left atrial contraction and 11(79%) patients were not on a regimen of antiarrhythmic medication. Conclusion: We conclude that Maze III operation without cryoablation is an effective surgical treatment in atrial fibrillation associated with the mitral valve disease.

• Land and Housing Review
• /
• v.2 no.4
• /
• pp.367-377
• /
• 2011

This paper investigates the determination factors' variation of real estate price after sub-prime financial crisis, in korea, using a VAR model. The model includes land price, housing price, housing rent (Jensei) price, which time period is from 2000:1Q to 2011:2Q and uses interest rate, real GDP, consumer price index, KOSPI, the number of housing construction, the amount of land sales and practices to impulse response and variance decomposition analysis. Data cover two sub-periods and divided by 2008:3Q that occurred the sub-prime crisis; one is a period of 2000:1Q to 2008:3Q, the other is based a period of 2000:1Q to 2011:2Q. As a result, Comparing sub-prime crisis before and after, land price come out that the influence of real GDP is expanding, but current interest rate's variation is weaken due to the stagnation of current economic status and housing construction market. Housing price is few influenced to interest rate and real GDP, but it is influenced its own variation or Jensei price's variation. According to the Jensei price's rapidly increasing in nowadays, housing price might be increasing a rising possibility. Jensei price is also weaken the influence of all economic index, housing price, comparing before sub-prime financial crisis and it is influenced its own variation the same housing price. As you know, real estate price is weakened market basic value factors such as, interest rate, real GDP, because it is influenced exogenous economic factors such as population structural changes. Economic participators, economic officials, consumer, construction supplyers need to access an accurate observation about current real estate market and economic status.

• Korean Journal of Soil Science and Fertilizer
• /
• v.41 no.2
• /
• pp.143-152
• /
• 2008

In order to share the understanding agricultural multifunctionality with people, we carried out quantification and monetary evaluation for controlling flood and fostering water resources function in paddy and upland farming in Korea. The amount of water controlling flood and fostering water resources function in paddy farming was much greater than that in upland. The quantification of flood control function could be estimated by sum of the height of dike and water infiltrated during the flooding periods in paddy farming, and water excepting runoff water from precipitation at flooding time in upland farming. As results of estimation of flood control function, the amounts of water controlling flood have been evaluated as $294mm\;year^{-1}$ in paddy farming and $72.6mm\;year^{-1}$ upland farming, and was calculated 3.71 billion MT on a nation basis in 2006. When it was carried out monetary estimation as the cost of dam construction and the depreciation expense by using replacement cost method, flood control functions in paddy and upland were evaluated as 44,338.9 and 7,221.5 billion won, respectively. Comparing with previous reports, monetary value was analyzed much to increase because of rising price cost recently. Fostering water resource functions were also quantified in paddy and upland farming as the amount of water keeping and infiltrating water during the cultivation. In the basis of estimation model, it was showed that paddy and upland farming had been estimated to have $414.28mm\;year^{-1}$, $18.7mm\;year^{-1}$, respectively. They were also calculated to 4.49 and 0.137 billion MT on a nation basis in 2006, respectively. The economic values of fostering water resources function in paddy and upland farming were also estimated to 1,769.4 and 52.8 billion won, respectively, as replacing the amount of water to the cost of drinking water in 2006. There were differences by much to the amounts of controlling flood function and fostering water resource between paddy and upland farming. It means that paddy farming more play an important role in environment than upland farming in Korea.