• Title/Summary/Keyword: ToF

Search Result 30,776, Processing Time 0.054 seconds

On the fixed-point theorems on the infrasolvmanifolds

  • Chun, Dae-Shik;Jang, Chan-Gyu;Lee, Sik
    • Communications of the Korean Mathematical Society
    • /
    • v.10 no.3
    • /
    • pp.681-688
    • /
    • 1995
  • Fixed-point theory has an extension to coincidences. For a pair of maps $f,g:X_1 \to X_2$, a coincidence of f and g is a point $x \in X_1$ such that $f(x) = g(x)$, and $Coin(f,g) = {x \in X_1 $\mid$ f(x) = g(x)}$ is the coincidence set of f and g. The Nielsen coincidence number N(f,g) and the Lefschetz coincidence number L(f,g) are used to estimate the cardinality of Coin(f,g). The aspherical manifolds whose fundamental group has a normal solvable subgroup of finite index is called infrasolvmanifolds. We show that if $M_1,M_2$ are compact connected orientable infrasolvmanifolds, then $N(f,g) \geq $\mid$L(f,g)$\mid$$ for every $f,g : M_1 \to M_2$.

  • PDF

Effects of LiF and TiO$_2$ Additions on Microwave Dielectric and Sintering Properties of ZnWO$_4$ (LiF 및 TiO$_2$ 첨가에 따른 ZnWO$_4$의 고주파 유전특성 및 소결특성)

  • Kim, Yong-Chul;Lee, Kyoung-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.07a
    • /
    • pp.131-134
    • /
    • 2003
  • [ $ZnWO_4$ ] shows excellent frequency selectivity due to its high quality factor($Q{\times}f$) at microwave frequencies. However, in order to use $ZnWO_4$ as multilayered wireless communication components, its other properties such as sintering temperature($1050^{\circ}C$), ${\tau}_f$ ($-70ppm/^{\circ}C$) and ${\varepsilon}_r(15.5)$ should be modified. In present study, $TiO_2$ and LiF were used to improve the microwave dielectric and sintering properties of $ZnWO_4$. $TiO_2$ additions to $ZnWO_4$ changed ${\tau}_f$ from negative to positive value, and also increased ${\varepsilon}_r$ due to its high ${\tau}_f$ ($+400ppm/^{\circ}C$) and ${\varepsilon}_r$(100). At 20 mol% $TiO_2$ addition, ${\tau}_f$ was controlled to near zero $ppm/^{\circ}C$ with ${\varepsilon}_r=19.4$ and $Q{\times}f=50000GHz$. However, the sintering temperature was still high to $1100^{\circ}C$. LiF addition to the $ZnWO_4+TiO_2$ mixture was greatly reduced the sintering temperature from $1100^{\circ}C$ to $850^{\circ}C$ due to liquid phase formation. Also LiF addition decreased the ${\tau}_f$ value due to its high negative ${\tau}_f$ value. Therefore, by controlling the $TiO_2$ and LiF amount, temperature stable LTCC material in the $ZnWO_4$-TiO_2-LiF$ system could be fabricated.

  • PDF

Gaze Effects on Spatial and Kinematic Characteristics in Pointing to a Remembered Target

  • Ryu, Young-Uk;Kim, Won-Dae;Kim, Hyeong-Dong
    • Physical Therapy Korea
    • /
    • v.13 no.4
    • /
    • pp.23-29
    • /
    • 2006
  • The purpose of the present study was to examine gaze effects on spatial and kinematic characteristics during a pointing task. Subjects were asked to watch and point to an aimed target (2 mm in diameter) displayed on a vertically mounted board. Four gaze conditions were developed as combinations of "seeing-aiming" in terms of the eye movements: Focal-Focal (F-F), Focal-Fixing (F-X), Fixing-Focal (X-F), and Fixing-Fixing (X-X). Both the home target and an aimed target were presented for 1 second and then were disappeared in F-F and X-F. In X-F and X-X, only an aimed target disappeared after 1 second. Subjects were asked to point (with index finger tip) to an aimed target accurately as soon as the aimed target was removed. A significant main effect of gaze was found (p<.01) for normalized movement time. Peripheral retina targets had significantly larger absolute error compared to central retina targets on the x (medio-lateral) and z (superior-inferior) axes (p<.01). A significant undershooting to peripheral retina targets on the x axis was found (p<.01). F-F and X-F had larger peak velocities compared to F-X and X-X (p<.01). F-F and X-F were characterized by more time spent in the deceleration phase compared to F-X and X-X (p<.01). The present study demonstrates that central vision utilizes a form of on-line visual processing to reach to an object, and thus increases spatial accuracy. However, peripheral vision utilizes a relatively off-line visual processing with a dependency on proprioceptive information.

  • PDF

The Early Wittgenstein on Russell's Paradox (전기 비트겐슈타인과 러셀의 역설)

  • Park, Jeong-il
    • Korean Journal of Logic
    • /
    • v.20 no.2
    • /
    • pp.163-196
    • /
    • 2017
  • Wittgenstein declares in the Tractatus Logico-Philosophicus that he resolved Russell's Paradox. According to him, a function cannot be its own argument. If we assume that a function F(fx) can be its own argument, a proposition "F(F(fx))" will be given, where the outer function F has a meaning different from the inner function F. In consequence, "F(F(fx))" will not be able to have a definite sense. Why, however, does Wittgenstein call into question a function F(fx) and "F(F(fx))"? To answer this question, we must examine closely Russell's own resolution of Russell's Paradox. Only when we can understand Russell's resolution can we do Wittgenstein's resolution. In particular, I will endeavor to show that the idea in Wittgenstein's 1913 letter to Russell provides a decisive clue for this problem.

  • PDF

Genetic Relatedness within Streptococcus pneumoniae Serotype 19F and 23F Isolates in Korea by Pulsed-Field Gel Electrophoresis

  • Lee, Kwang-Jun;Bae, Song-Mee;Hwang, Kyu-Jam;Lee, Young-Hee;Kim, Ki-Sang
    • Journal of Microbiology
    • /
    • v.41 no.1
    • /
    • pp.1-6
    • /
    • 2003
  • The genetic relatedness of multidrug-resistant pneumococcal isolates of serotypes 19F and 23F was investigated. The DNA fragments digested with Sma I were resolved by pulsed-field gel electrophoresis (PFGE). PFGE analysis of 365. pneumoniae isolates showed 13 different patterns. Among 22 isolates of serotype 19F, 9 different PFGE patterns were present and 14 isolates of serotype 23F isolates represented 5 distinct PFGE patterns. Two isolates of serotype 19F and six isolates of serotype 23F shared the same PFGE pattern (Pattern I). Based on the genetic relatedness within the strains (one genetic cluster was defined as having more than 85% homology), we divided the pneumococcal strains into genefic clusters (Ⅰ, II, III, IV, V, and VI). The 22 strains of serotype 19F belonged to five distinct genetic clusters (I, II, III, IV, V and VI) and 14 strains of serotype 23F represented two genetic clusters (I and II ). These results showed that strains of serotype 19F are genetically more diverse than those of serotype 23F, Serotype 19F isolates with PFGE patterns H and I appeared to be less related to those of the remaining PFCE patterns (A to G) (less than 60% genetic relatedness), but those strains were genetically closely related with serotype 23f. These results suggest that the latter isolates originated from horizontal transfer of the capsular type 19F gene locus to 23F pneumococcal genotypes. In conclusion, the multidrug-resistant pneumococcal isolates of serotype 19f and 23F isolated in Korea are the result of the spread of a limited number of resistant clones.

On the growth of entire functions satisfying second order linear differential equations

  • Kwon, Ki-Ho
    • Bulletin of the Korean Mathematical Society
    • /
    • v.33 no.3
    • /
    • pp.487-496
    • /
    • 1996
  • Let f(z) be an entire function. Then the order $\rho(f)$ of f is defined by $$ \rho(f) = \overline{lim}_r\to\infty \frac{log r}{log^+ T(r,f)} = \overline{lim}_r\to\infty \frac{log r}{log^+ log^+ M(r,f)}, $$ where T(r,f) is the Nevanlinna characteristic of f (see [4]), $M(r,f) = max_{$\mid$z$\mid$=r} $\mid$f(z)$\mid$$ and $log^+ t = max(log t, 0)$.

  • PDF

Expession of the Recombinant Klebsiella aerognes UreF Protein as a MalE Fusion

  • Kim, Keun-Young;Yang, Chae-Ha;Lee, Mann-Hyung
    • Archives of Pharmacal Research
    • /
    • v.22 no.3
    • /
    • pp.274-278
    • /
    • 1999
  • Expression of the active urease of the enterobacterium, Klebsiella aerogens, requires the presence of the accessory genes (ureD, ureE, ureF, and ureG) in addition to the three structural genes (ureA, ureB, and ureC). These accessory genes are involved in functional assembly of the nickel-metallocenter for the enzyme. Characterization of ureF gene has been hindered, however, since the UreF protein is produced in only minute amount compared to other urease gene products. In order to overexpress the ureF gene, a recombinant pMAL-UreF plasmid was constructed from which the UreF was produced as a fusion with maltose-binding protein. The MBP-UreF fusion protein was purified by using an amylose-affinity column chromatography followed by an anion exchange column chromatography. Polyclonal antibodies raised against the fusion protein were purified and shown to specifically recognize both MBP and UreF peptides. The UreF protein was shown to be unstable when separated from MBP by digestion with factor Xa.

  • PDF

The Idea and the Role of Field-Museums in Japan

  • Horie, Noriko;Tabata, Sadatoshi
    • Proceedings of the Korean Institute of Landscape Architecture Conference
    • /
    • 2007.10b
    • /
    • pp.202-207
    • /
    • 2007
  • Recently, the number of 'field-museums(F.Ms.)' in Japan has increased. Although they are very diverse, the essential commonality is that each has a field arranged as a kind of museum. In this study, we examine the 'F.M.' mainly through documents in order to understand the concept of the F.M. and the direction of further studies. Before examining the cases of F.Ms., we explore the history of the F.M. and the role of museums in order to establish the background of the development of F.Ms. The term F.M. first appeared and evolved in 1990s. It is suggested that F.Ms. are positioned on the same lines as development of museums, and that the field of museums and the field of landscaping is beginning to overlap. Concerning the role of museums, we examined the definition of museums in terms of conventional museums and regional planning. Next, the documents of 36 cases of F.Ms. are checked regarding their types and roles. Consequently, we found that while most F.Ms. cases have both the role of conventional museums and the role of regional planning, it is difficult to say that the role has some connection with the type. It seems that F.Ms. emphasize 'education' rather than 'collection', 'pleasure' and 'research', compared with conventional museums. In addition, the role of regional planning is strongly expected. In many cases, the F.M. is expected to be a method of regional management, not merely a museum. In order to use F.Ms. for regional planning and landscaping effectively, it is desirable for F.Ms. to be defined from this viewpoint. For this purpose, it is necessary to determine the extent of F.Ms. The problem is which extent to choose, geographical unity or administrative border. Hence, further comparative research is needed clarify the association between the extent and the identity in order to establish a more effective size of F.Ms.

  • PDF

Single and Four-Week Subcutaneous Toxicity Studies of a Bee Venom Extracts (F1, F3) In Rats (봉독 추출물(Fl, F3)의 랫드에 대한 단회 및 4주 반복 피하 투여 독성시험)

  • 박기수;조성대;안남식;정지원;양세란;박준석;홍인선;서민수;조은혜
    • Toxicological Research
    • /
    • v.19 no.1
    • /
    • pp.51-66
    • /
    • 2003
  • This study was performed to evaluate single and repeated-dose toxicities of Bee Venom Extracts (F1, F3) in Spraque-Dawley. F1 was injected subcutaneously to rat at dose levels of 0, 0.0002, 0.002, 0.02 mg/kg/day for single-dose toxicity study and repeated-dose toxicity study. F3 was injected subcutaneously to rat at dose level of 0, 0.003, 0.03, 0.3 mg/kg/day for single-dose toxicity study and repeated-dose toxicity study. In both studies, there were no dose related changes in mortality, clinical sign, body weight change, food and water consumption, opthalmoscopy, organ weights, urine analysis, biochemical examination, and hematological findings of all animals treated with Bee Venom (F1, F3). Gross and histopathological findings revealed no evidence of specific toxicity related to Bee Venom (F1, F3). These results suggest that the subcutaneous NOEL (No Observed Effect Level) of Bee Venom (F1, F3) may be over F1 -0.02 mg/kg, F3-0.3 mg/kg.

A Study on the Patient Care Standard (환자간호실무 표준에 관한 연구)

  • Yoon, Suck-Hee;Kang, Chai-Won;Jurn, Mee-Soo;Kim, Yong-Soon;Kim, Moung-Ock;Park, Sung-Ae;Kim, Hye-Ja;Lee, Byung-Sook;Jung, Myun-Sook;Jun, Myung-Hee
    • The Korean Nurse
    • /
    • v.31 no.1
    • /
    • pp.68-87
    • /
    • 1992
  • The purpose of this study is to develop a patient care standard which is the basis of unit based quality assurance. The subjects were 570 nurses of 6 hospitals is Seoul. Patient Care Standards were developed from 3 times of clinical Nurses Association's workshop & the joint meeting of Clinical Nurses Association & the Korean Nurses Academic Socity of Nursing Administration. Respondents were instructed to rate of the 2 types of 5 - point Likert type questionnaire(one is the level of perceived importance, the other is the level of actual performance) Findings of this study were as follows 1. As a results of reliability analysis, each questionnaire ranged from $\alpha$=0.79 to 0.94

    2. The Correlations between the levels of perceived importance & actual performances were ranged from r=.40 to 0.72(P=.00) 3. There were significant differences in the level of percevied importance according to the several variables. $\circled1$ Chemotherapy unit; df=5, F=4.06, P=.000/hospital $\circled2$ Pediatric unit; df=5, F=2.8, P=.02/hospital $\circled3$ OBGY ; df=5, F=4.20, P=.00/hospital $\circled4$ ICU ; df=5, F=2.83, P=.02/hospital df=3, F=5.38, P=.00/age df=3, F=6.22, P=.00/total duration. $\circled5$ GS ; df=3, F=3.37, P=.02/total duration 4. There were significant difference in the level of actual performance according to the several variables. $\circled1$ Chemotherapy unit; df=5, F=2.89, P=.02/hospital df=3, F=3.07, P=.03/age df=3, F=3.61, P=.02/total duration $\circled2$ OBGY ; df=5, F=15.48, P=.00/hospilal df=3, F=7.83, p=.00/total duration $\circled3$ GS ; df=5, F=6.70, P=.00/hospital df=3, F=4.49, P=.01/age df=3, F=5.99, P=.00/total duration $\circled4$ ICU ; df=5, F=2.96, P=.02/hospital df=3, F=4.39, P=.0l/age df=3, F=5.20, P=.00/total duration

  • PDF