• Journal of KIISE
• /
• v.43 no.12
• /
• pp.1412-1419
• /
• 2016

In cognitive radio sensor networks (CRSNs), secondary users (SUs) can occupy licensed bands opportunistically without causing interferences to primary users (PUs). SUs perform spectrum sensing to detect the presence of PUs. Sensing time is a critical parameter for spectrum sensing that can yield a tradeoff between sensing performance and secondary throughput. In this study, we investigate new approaches for spectrum sensing by exploring the tradeoff from a) spectrum sensing for PU detection (SSPD) and b) spectrum sensing for secondary throughput (SSST). In the proposed scheme, the first sensing result of the current frame determines the dynamic performance of the second spectrum sensing. Energy constraint in CRSNs leads to maximized network energy efficiency via optimization of sensing time. Simulation results show that the proposed scheme of SSPD and SSST improves network performance in terms of energy efficiency and secondary throughput, respectively.

• The Journal of the Korean Society for Microbiology
• /
• v.16 no.1
• /
• pp.19-28
• /
• 1981

The Pseudomonas infection has been increased in incidence and suspected as a cause of opportunistic pathogen. Protease and elastase produced by Pseudomonas aeruginosa are reported to be closely associated with pathogenicity of Pseudomonas aeruginosa. We examined, in this work, the relationship between production of exoenzyme of Pseudomonas aeruginosa and susceptibility to antimicrobial agents in view of possible application to the management of Pseudomonas infection. 1. In 295 Pseudomonas aeruginosa isolated from clinical specimens, 34.6% were from pus, 20.7% from sputum, 15.6% from wound including burn sites and 12.9% from urine. 2. Distribution of protease and elastase production by clinically isolated Pseudomonas aeruginosa, showed that protease and elastase producing strains were 83.1%, protease producing strains were 7.5%, elastase producing strains were 2.0%, and non producing strains were 7.5%. 3. MIC(minimum inhibitory concentration) peak for tetracycline and chloramphenicol were observed at 25mcg/ml and 200mcg/ml respectively, but there were no Pseudomonas aeruginosa which correspond to MIC peak, 6.25mcg/ml. Gentamicin of aminoglycosides was highly susceptible to Pseudomonas aeruginosa clinically isolated from pus, sputum and wound sites, but susceptible to isolates from nasal discharge and urine. Regarding MIC peak of carbenicillin, 100mcg/ml, 81.8% of Pseudomonas aeruginosa were from urine, 54.8% from wound including burn sites, 52.7% from pus, and 50.8% from sputum. 4. Enzyme producing strains showed no susceptibility to kanamycine and carbenicillin at low concentration, but protease producing strains tend to resistant to antimicrobial agents.

• International journal of advanced smart convergence
• /
• v.7 no.3
• /
• pp.23-36
• /
• 2018

In wireless communication, efficient spectrum usage is an issue that has been an attractive research area for many technologies. Recently new technologies innovations allow compact radios to transmit with power efficient communication over very long distances. For example, Low-Power Wide Area Networks (LPWANs) are an attractive emerging platform to connect the Internet-of-Things (IoT). Especially, LoRa is one of LPWAN technologies and considered as an infrastructure solution for IoT. End-devices use LoRa protocol across a single wireless hop to communicate to gateway(s) connected to the internet which acts as a bridge and relays message between these LoRa end-devices to a central network server. The use of the (ISM) spectrum sharing for such long-range networking motivates us to implement spectrum sensing testbed for cognitive radio network based on LoRa and GNU radio. In cognitive radio (CR), secondary users (SUs) are able to sense and use this information to opportunistically access the licensed spectrum band in absence of the primary users (PUs). In general, PUs have not been very receptive of the idea of opportunistic spectrum sharing. That is, CR will harmfully interfere with operations of PUs. Subsequently, there is a need for experimenting with different techniques in a real system. In this paper, we implemented spectrum sensing for cognitive radio networks based on LoRa and GNU Radio, and further analyzed corresponding performances of the implemented systems. The implementation is done using Microchip LoRa evolution kits, USRPs, and GNU radio.

• Journal of Science and Technology Studies
• /
• v.7 no.1
• /
• pp.151-175
• /
• 2007

What are the differences between science communication and science culture? This paper discusses the relationship between 'science communication' and 'science culture', with a consideration of recent activities and endeavours aiming public's understanding of science. For this, it starts with the outcomes and significance of the 9th International Conference on Public Communication of Science and Technology(PCST-9), with a theme of "Scientific Culture for Global Citizenship", held in Seoul May, 2006. Then, it discusses 'Public Understanding of Science(PUS)' to which the PCST network movement is linked, in comparison with 'Popularization of Science(PS)' and 'Science and Society(S&S)'. While PS was one directional movement conveying scientific knowledge to the public, PUS appeared from 1980s was an intentional effort for activating science communication through mass media. Whereas, a recent S&S movement emphasizes dialogue between science and society. And it then introduces theoretical as well as functional definitions of 'science culture' particulary in Korean and explains how the concept of science communication has considerably expanded since 2002. From this, it is finally argued that science communication needs be redefined as a practice of science culture.

• Journal of the korean veterinary medical association
• /
• v.15 no.8
• /
• pp.463-466
• /
• 1979

In treatment of empyema of frontal sinus in a dairy cow, modified trephing method was applied and aquired satisfactory drainage of pus and discharge from frontal sinus. Methods of trephing opening applied were as follows : 1. Site of trephing opening for

• Journal of Korean Medical classics
• /
• v.22 no.1
• /
• pp.207-228
• /
• 2009

Objective : To find the main symptoms associated with atopic dermatitis and to get the utmost out of information about cause, treatment are contribute in the treatment of atopic dermatitis rather than looking for ways through how to connect modern atopic dermatitis and a listed symptom of classic literature. Method : In this research, we recorded about the main symptoms of atopic dermatitis such as itch, erythema, edema, pus and furuncle. Also we interpreted original text by extracting a sentence containing the terms like red[赤], pus[膿], flare[發赤], dermatosis[溞], swelling[洋], light red[紅], itch[瀁], worm running[蟲行], juice[汁], rash[癮疹], variegation[疹斑] and summarized cause of symptoms, disease sign, prescription. Results : There are the cause of many symptoms accompanied by atopic dermatitis in the body that recorded unpreparedness[虛], Wind[風], Fever[熱], unpreparedness & interruption of vitality hole[氣穴不通], unpreparedness & Wind, Wind Fever[風熱], Wind Coldness[風寒], Wind Humidity[風濕], Humidity Fever[濕熱], Wind Humidity Fever, Wind of Lungs[肺風], Wind of Lungs and Spleen[脾肺風], the Kidney Wind poison[腎臟風毒], Wind of Lungs Fever, Worm[蟲], miscellaneous vitality[雜氣], unpreparedness and Fever of Heart[心虛熱], old sore of kidney poison[久瘡腎臟風毒].

• Journal of Korean Neurosurgical Society
• /
• v.29 no.7
• /
• pp.945-948
• /
• 2000

A sixty-three year old woman presented with sudden onset of dystonic twitching of the extremities and repeatedly downgrading of consciousness in the midnight. She had no history of medical illness in the past but had been suffered from fatigue recently before the onset of the attack. At admission she was neurologically free including neuro-ophthalmologic examination. MRI showed a high signal T1WI mass in the sella protruding into the suprasellar cistern. Hormonal study revealed low value of T3, T4, LH and FSH. Under the impression of pituitary apoplexy she underwent operation via transcranial route. When the protruding diaphragma sellae was opened, milkish pus spilled out. The thick capsule was biopsied and pus was sent for the study. The results of Gram staining and culture were both negative but pathologic report of the specimen was high infiltration of lymphocytes with few polymorphs.

• The Journal of the Korean Society for Microbiology
• /
• v.17 no.1
• /
• pp.57-66
• /
• 1982

The correlation between the serotypes and sensitivity distribution of Pseudomonas aeruginosa was studied with stock strains of department, strains isolated from various clinical sources and strains of haspital environment of the past two years. Two hundred and fifty seven strains were typable and 38 strains were untypable out of 295 clinical sorces. Serotype B was most provalent(27.6%) followed by serotype G(24.9%), serotype E(23.3%) and serotype A(7.8%) among 257 typable strains. However, no serotype J,L and M were observed. Serotype B,G,E and A were isolated from pus, sputum, wound, burn site and urine. Serotypes E were most frequently isolated from nasal discharge and serotypes K were isolated from pus. There were no apparent differences in sensitivity distribution of streptomycin, carbenicillin and ampicillin between the clinical and The environmental origin. However, the strains of environmental origin were found to be relatively more susceptable to tetracycline, gentamicin and fradiomycin than the strains of clinical sources in high concentration. The strains of clinical sources of serotype B,G,E and A showed different resistant patterns to all antimicrobial agents except for carbenicillin. Serotype E showed the highest percentage resistance followed by serotype G,B and A.

• The Journal of the Acoustical Society of Korea
• /
• v.23 no.2
• /
• pp.109-116
• /
• 2004

This paper deals with data association using 3 sets of passive linear array sonars (PUS) geometrically positioned in a Y-shaped configuration, but fixed in an underwater environment. The data association problem is directly transformed into a 3-D assignment problem, which is known to be NP-hard. For generic passive sensors, it can be sotted using conventional algorithms, while it in PLAS becomes a formidable task due to the presence of bearing ambiguity. In particular, we proposed data association method robust to bearing measurements errors by incorporating frequency information and analyze a region of ghost problem by geometrical relation PUS and target. We analyzed the effectiveness of the proposed method by representative simulation in multi-target.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.24 no.1
• /
• pp.47-55
• /
• 1994

Post operative maxillary cyst may arise after the surgical treatment for maxillary sinusitis with the symtoms of swelling, pain, and pus discharge in the buccal region. It is examined by Waters' view, panoramic view and other intraoral radiographs, but quite variable radiologically. Most of the cyst is seen round or ovoid shape radiolucency, destruction, expansion and thinning of the lateral wall or posterior wall, and roots of the adjacent teeth may be resorbed. We studied about 117 cases of the post operative maxillary cysts which diagnosed in department of oral and maxillofacial radiology, Seoul National University Hospital. We analyzed and obtained following results. 1. These cysts occured more frequently in male than in female and the incidence is highest in the 4th and 5th decade. 2. Initial radical operation of maxillary sinus were performed mainly between the age of 10 and 45 years, and about 60% of the patients were 15 to 25 years. 3. Pain and swelling on buccal area, pus discharge, and toothache are most chief compaints, seven cases were found at routine examination without symtoms. 4. Most of these cysts were unilocular with smooth and well-defined border. 5. The majority of the cysts occurred in the anterolateral wall of maxillary sinus. 6. Dental changes of the lesional area were loss of lamina dura and root resorption, but about 55% were not changed.