An important aspect of the present invention is a method for inhibiting proliferation of a DNA virus dependent upon events associated with cell proliferation for replication. The DNA virus includes any of the herpesvirus family, and most particularly human cytomegalovirus. The method involves administering prophylactically or therapeutically effective amount of a cyclin-dependent kinase inhibitor to a patient or animal.

The entire text of the above-referenced disclosure is specifically incorporated by reference herein without disclaimer.
The present invention relates generally to the fields of prophylaxis and treatment for viral infections. More particularly, it concerns the use of cyclin dependent kinase inhibitors for blocking replication of any DNA virus dependent on Cdk activity for proliferation, an example being herpesvirus and, more particularly, cytomegalovirus. Marek""s disease represents a chicken-CMV, equine abortion virus represents a horse variety and cattle have several specific CMV""s, to name but a few species-specific CMV""s.
Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus that infects greater than 80% of the human population. HCMV is capable of establishing a life-long infection following primary infection. Reactivation of HCMV often results during pregnancy, perfusion, and in immunocompromised states (Huang and Kowalik, 1993). HCMV rarely causes symptomatic disease in healthy immunocompetent individuals. However, HCMV can result in severe clinical manifestations in congenitally infected newborns and in immunocompromised individuals, such as those undergoing organ transplantation or those infected with HIV (Alford et al., 1990; Schooley, 1990; Rubin, 1990). Most animal species may be infected with species-specific cytomegalovirus.
HCMV is the most common cause of human congenital viral infections, occurring in approximately 1% of all new born infants (Weller, 1971; Alford et al., 1981). Congenital infections (e.g., those acquired during pregnancy) primarily result from reactivation of a latent infection in the mother and subsequent transmission to the fetus. The majority of HCMV infections are asymptomatic or subclinical. However, about 10% of infants infected in utero display clinical manifestations, approximately 5% display typical cytomegalic inclusion disease (CID), with the other 5% presenting atypical manifestations (Pass et al., 1980). Characteristic manifestations of CID include hepatomegaly, splenomegaly, microcephaly, jaundice, and petechiae (Weller and Hanshaw, 1964). The prognosis for congenital CID is bleak with the mortality rate reaching 30%. The surviving infants may suffer from severe mental and motor abnormalities (Alford et al., 1990).
Perinatal infections are acquired during or shortly after birth. It is estimated that 1 to 15% of infants born in the United States become infected with HCMV by 6 months of age (Alford et al., 1990). The majority of these, infections occur via ingestion of infected breast milk and contact with genital secretions during birth. Approximately 40-60% of infants breast-fed by sero-positive mothers and 25-50% of infants exposed to HCMV in the birth canal become infected (Stagno et al., 1980; Dworsky et al., 1983; Reynolds et al., 1973). The vast majority of these perinatal infections remain asymptomatic. However, there is evidence that perinatal HCMV infection may be associated with interstitial pneurmonitis and result in chronic lung disease (Brasfield et al, 1987).
HCMV""s ability to latently infect cells and become reactivated under immunosuppressed conditions pose a severe problem for AIDS patients (Chou, 1990; Drew et al., 1981; Quinn et al., 1987). Essentially 100% of HIV positive homosexual men present serological evidence of either recently acquired or reactivated HCMV infection (Collier et al,. 1987). According to Schooley (1990), HCMV can play at least four possible roles in the pathogenesis of AIDS. These include: 1) direct HCMV-induced morbidity associated with clinical symptoms, 2) increased immunosuppression induced by HIV, 3) enhanced HIV replication by trans-activation at the cellular level, and 4) destruction of the gastrointestinal mucosa, and predisposition to other infections.
HCMV infection is the primary cause of death in over 35% of AIDS patients (Gehrz, 1991). HCMV infection affects numerous organ systems including the central nervous system (CNS), pulmonary system, and gastrointestinal (GI) tract (Smith and. Brunnessel, 1994). HCMV infection of the CNS has been observed in more than 20% of AIDS patients at autopsy. Individuals with CNS infections present with clinically recognized neurological symptoms including encephalitis, polyradiculomyelitis, and neuropathy (Navia et al., 1986; Hawley et al., 1983; Said et al., 1991). It is estimated that xcx9c20% of AIDS patients will develop a gastrointestinal disease caused by HCMV (Dieterich et al., 1993). HCMV infection can result in lesions involving the oral mucosa, esophagus, intestine, and rectum (Kanas et al., 1987). The pain associated with these lesions of the GI tract can obstruct the intake of food and thus contribute to the already poor nutritional status of the patient (Villor et al., 1984).
HCMV also affects the immunological state of AIDS patients. HCMV induces numerous immunological abnormalities that can inhibit the patients ability to fight HIV and other infections. These abnormalities include; changes in the relative distribution of CD4 and CD8 T-lymphocytes (Drew et al., 1985; Detels et al., 1984), a decrease in release of and responsiveness to mitogens, (Kapasi and Rice, 1988; Sing and Garnett, 1984) altered HLA-DR expression, and altered antigen presentation (Fiala et al., 1993).
Interestingly, HCMV may also enhance HIV replication at a molecular level. Previous studies have demonstrated that HCMV and HIV can co-infect numerous cell types (Rice et al., 1984; Nelson et al., 1988). This coinfection of HCMV and HIV can result in the enhancement of HIV replication via the trans-activation of the long terminal repeat (LTR) sequences by HCMV regulatory elements (Schooley, 1990). Although the complete mechanism is far from clear, the net result is enhanced expression of the LTR and increased HIV replication.
A second group of individuals with increased risk of HCMV infection are organ transplant recipients. HCMV is the single most important infectious agent affecting organ recipients. At least two-thirds of these patients develop a HCMV-infection 1-4 months after transplantation (Rubin, 1990). According to Rubin (1990) there are three patterns of HCMV infection following organ transplantation; primary infection, reactivated infection, and superinfection. Primary infection has the greatest clinical impact and occurs when an individual who is sero-negative for HCMV becomes infected by a sero-positive donor organ or transfused blood. In reactivated infection the HCMV sero-positive recipient undergoes reactivation of endogenous latent virus. Virtually all organ recipients who are scro-positive for HCMV will show some evidence of HCMV reactivation (Rubin and Tolkoff-Rubin, 1984; Fiala et al., 1975). Finally, superinfection occurs when a sero-positive recipient receives an allograft from a sero-positive donor that is infected with a different HCMV strain.
HCMV-infection itself can result in a wide variety of conditions ranging from fevers to pneumonia and hepatitis (Rubin, 1990). Secondly, HCMV infection can produce an immunosuppressed state that exceeds that observed from the immunosuppressive drugs alone. This enhanced immunosuppression can result in increased opportunistic infections due to Pneumocystis carinii, fungi, and Listeria monocytogenes (Rubin, 1990). Finally, HCMV can directly contribute to the rejection of the allograft. These complications demonstrate the need to better understand the HCMV life cycle. Understanding the molecular mechanisms of HCMV replication should aid in the development of novel anti-virals to help control the spread and replication of HCMV.
The structure of the HCMV virion shares characteristics consistent with other DNA viruses, particularly the herpesviruses. The HCMV virion consists of four basic elements: 1) an electron-opaque core, 2) an icosahedral capsid surrounding the core, 3) a tegument surrounding the capsid, and 4) an envelope (Roizmnan and Sears, 1991).
HCMV gene expression is regulated by a complex interaction of both viral and cellular proteins (Huang and Kowalik, 1993). The most complex and well studied HCMV regulatory element is the major immediate early promoter (MIEP) which promotes transcription of the immediate early genes. The MIEP is an extremely strong and complex promoter containing numerous binding sites for cellular transcription factors that regulate IE gene expression (Boshart et al., 1985; Samnbuchetti et al., 1989). The MIEP contains various 17,18, 19, and 21 base pair repeats upstream of the transcriptional start site for IE1 and IE2. These repeats contain binding sites for cellular transcription factors such as NFxcexaB, SP1, NF1, and ATF/CREB. Other cis elements located outside the repeat elements include a serum-response element (SRE), glucocorticoid-response element (GRE), and AP-1 binding sites (reviewed in Huang and Kowalik, 1993). All of these cis-elements are thought to play important roles in regulating transcription from the MIEP. However, HCMV gene expression is not controlled exclusively by cellular transcription factors. The major immediate early proteins also play critical roles in regulating the MIEP. IE72 and 55 can upregulate transcription from the MIEP (Cherrington and Mocarski, 1989; Stenberg et al., 1990; Baracchini et al., 1992), whereas IE86 represses transcription from the MIEP (Stenberg et al., 1990). This repression by IE86 presumably occurs by direct or indirect interaction with a cis-repression signal in the MIEP that spans the transcriptional start site (Cherrington et al., 1991; Liu et al., 1991). Control of the MIEP by IE72, 55, and 86, is believed to provide an intermediate level of promoter activity necessary for maintaining proper levels of IE proteins for subsequent viral and cellular gene activation (Stenberg et al., 1990). HCMV early and late promoters are also regulated by IE proteins (Malone et al., 1990; Staprans et al., 1988). However, these promoters require both IE72 and IE86, along with cellular transcription factors for maximal expression (Chang et al., 1989; Depto and Stenberg, 1989; Malone et al., 1990). An example of this regulation occurs in transcription of the HCMV DNA polymerase gene. Transcription of the polymerase gene requires both IE72 and IE86 proteins together with the cellular transcription factor USF for promoter activity (Klucher et al., 1989). Immediate early proteins are also involved in activating cellular promoters. Recent studies have demonstrated HCMV""s ability to activate cellular genes such as, dihydrofolate reductase (Margolis et al., 1995), thymidine kinase (Estes and Huang, 1977), and topoisomerase II (Benson and Huang, 1990). Some of these promoters are regulated by interaction of IE proteins and cellular transcription factors (Margolis et al., 1995). The ability of HCMV to induce transcription and expression of these cellular genes is believed to be critical for successful viral replication.
The time required for maximal HCMV DNA synthesis is quite long compared to other herpesviruses. HCMV encodes its own DNA polymerase which is responsible for the synthesis of viral DNA. The HCMV DNA polymerase is a 140 kDa protein that possesses 3xe2x80x2 exonuclease activity (Huang, 1975a; Nishiyama et al., 1983). The HCMV polymerase is structurally and functionally distinct from cellular DNA polymerases and can be specifically inhibited by chemicals such as phosphonoacetic acid (Huang, 1975b).
HCMV DNA synthesis appears to occur in a biphasic manner, with synthesis beginning approximately 12 hrs post-infection. The first phase of synthesis slows at about 24 hr post-infection (Albrecht, 1989; Stinski, 1978). Maximum viral DNA synthesis, however, does not occur until 72-96 hr post-infection (Albrecht. 1989; Stinski, 1978). The reason for this slow rate of viral DNA synthesis is presently unknown. Some researchers have speculated that since HCMV stimulates host cell macromolecular synthesis, that at early times after infection when macromolecules are limiting, HCMV does not compete well with the host cell for these factor (Stinski, 1991). According to this hypothesis, the virus must first induce synthesis of macromolecules (i.e., nucleotides) before efficient viral DNA synthesis can occur.
The early events that one observes upon HCMV infection share many aspects in common with the cellular immediate early response that is provoked by addition of serum growth factors to serum-starved cells. The virus precipitates a very rapid increase in the intracellular concentration of many important second messengers (reviewed in Albrecht et al, 1989), including calcium, inositol trisphosphate, and diacylglycerol. Protein kinase C, along with phospholipase A2 are also activated following infection (AbuBakar et al., 1990). HCMV infection also induces dramatic changes in Na+/IK+ ATPase activity following infection (Albrecht et al., 1989). Albrecht (1989) has proposed that these changes in second messengers and intracellular ions are crucial for the morphological and pathological responses observed following HCMV infection.
HCMV replication in vivo occurs in terminally differentiated cells of epithelial and endothelial origin (Weller, 1971). Therefore, successful viral replication requires activation of the DNA synthetic machinery, as well as those pathways that are involved in biosynthesis of macromolecular precursors (nucleotides, polyamines, etc.). These processes are stringently repressed in post-mitotic cells. However, HCMV is capable of overcoming these restrictions to allow for viral replication. HCMV infection is capable of inducing numerous cellular genes involved in production of biosynthetic precursors and genes involved in transcriptional regulation. The expression of cellular immediate early genes such as c-fos, c-jun, and c-myc, all of which can act as transcription factors, are increased following HCMV infection (Boldogh et al., 1990; Monick et al., 1992; Colberg-Poley and Santomenna, 1988). Biosynthetic genes involved in nucleotide production such as dihydrofolate reductase, thymidine kinase, and ornithine decarboxylase are also induced following HCMV infection (Margolis et al., 1995; Estes and Huang, 1977; Isom, 1979). The induction of these genes demonstrates HCMV""s ability to overcome some of the restrains present in post-mitotic cells and induce the production of precursors required for HCMV replication.
It is generally agreed that in some cell types HCMV is capable of evoking a complete mitogenic response leading to replication of the host cell genome. (Albrecht et al., 1976; DeMarchi, 1983; Fumkawa et al., 1975; Kamiya et al., 1986). However, many (perhaps all) of these cells that exhibit a complete mitogenic response upon viral infection do not replicate the viral genome and fail to produce progeny virus (Albrecht et al., 1976; DeMarchi, 1983; Albrecht et al., 1989). The data suggest that failure to express the full complement of viral genes needed for HCMV replication may permit host cell DNA replication, such that a complete mitogenic response appears to be characteristic of cells that undergo abortive infection.
In cells that produce virus progeny (i.e., during productive infection), there is controversy concerning the extent to which the virus is capable of activating host cell DNA synthesis. It is clear that productively infected cells exhibit many manifestations of mitogenic stimulation (Albrecht et al., 1989; Yurochko et al., 1995; Bresnahan et al., 1996a; Wade et al., 1992; Estes and Huang, 1977; Jault et al., 1995). Some investigators have reported that complete (or nearly complete) replication of the cellular genome attends HCMV DNA synthesis in productively infected cells (Jault et al., 1995; St. Jeor and Hutt, 1977), leading to arrest of infected cells in a state that resembles G2 or M phase of the cell cycle (Jault et al., 1995). Other investigators have been unable to detect cellular DNA synthesis in cells that are replicating HCMV DNA and producing virus progeny (De Marchi, 1983; Albrecht et al., 1989, Bresnahan et al., 1996a). Thus, it is unclear to what extent HCMV is capable of eliciting a complete mitogenic response, leading to activation of the cellular DNA synthetic machinery and a significant increase in host cell DNA synthesis during the course of productive viral replication. Neither is it certain how the virus subverts the normal, post-mitotic constraints on DNA synthesis and biosynthesis of macromolecular precursors.
The ability of HCMV to activate cells is an important step in HCMV replication. However, the controversy of whether or not HCMV elicits a complete mitogenic signal and stimulates cellular DNA synthesis is ongoing. The cell cycle is divided into four distinct phases referred to as G1, S, G2 and M phase. These four phases encompass distinct molecular events that direct cell division. DNA synthesis and replication of the cellular genome occurs in S phase. The molecular events involved in chromosome separation and the formation of daughter cells occurs in M phase or mitosis (reviewed in Alberts et al., 1989). Gap 1 or G1 occurs after mitosis (cell division) and prior to the initiation of S phase. It is during this G1 phase that the cell will make a decision either to become quiescent or commit to another round of DNA replication (reviewed in Draetta, 1994; Sherr, 1994). Gap 2 or G2 represents the time between S phasc and the initiation of mitosis (Alberts et al., 1989). Recent studies have begun to elucidate the mechanisms involved in regulating progression through each of these phases. These mechanisms arc crucial for faithful replication of the genome and successful cell proliferation. Although the picture is far from clear some key genes regulating cell cycle progression have been identified.
Progression through the eukaryotic cell cycle is regulated by a family of serine/threonine protein kinases called cyclin-dependent kinases or Cdks (reviewed in Draetta, 1994; Sherr, 1993; Sherr, 1994). The activity of Cdks are closely regulated by numerous mechanisms some of which include, specific binding to regulatory subunits, called cyclins, binding to inhibitory subunits called cyclin kinase inhibitors (CKIs), phosphorylation, dephosphorylation, and protein degradation (reviewed in Elledge and Harper, 1994; Morgan, 1995; Sherr, 1994). The temporal activation and binding of cyclins to specific Cdks is shown in FIG. 1. The regulation and activity of Cdks is essential for successful cell cycle progression and cell proliferation.
Cdks comprise a family of at least 10-12 enzymes. Some of these enzymes have been studied in considerable detail. The first Cdk was identified in fission and budding yeast and designated cdc2 and cdc28, respectively (Nurse and Bissett, 1981; Lorincz and Reed, 1984). Cdk1 is the metazoan homologue of cdc2 and cdc28 (Hanks, 1987). Cdk1 complexes with both cyclins A and B and plays a critical role in regulating the G2/M phase transition (Sherr, 1983; Draetta, 1994). Cdk3 has been implicated in progression through G1 phase of the cell cycle (van den Heuvel and Harlow, 1993), but little more is known of this enzyme. Cdk5 functions in neural tissues (Lew et al., 1994). Cdk7 is the catalytic subunit of the Cdk activating kinase (CAK), which as the name implies, plays a role in regulating Cdk activity (Fesquet et al., 1993; Fisher and Morgan, 1994). Cdk2, Cdk4, and Cdk6 are thought to play critical roles in G1 phase progression. The precise details are far from clear, but it is generally believed that Cdk4 and Cdk6 regulate processes that are essential for progression through mid to late G1 phase; whereas Cdk2 regulates processes that are involved in the initiation of S phase (reviewed in Draetta, 1994; Sherr, 1993; Sherr, 1994). Cdk4 and Cdk6 are activated by association with one or another of the D-type (D1, D2, D3) cyclins (Bates et al., 1994; Matsushime et al., 1992; Meyerson and Harlow, 1994). Cdk2 is activated primarily by association with cyclin E or cyclin A (Dulic et al., 1992; Koff et al., 1992; Rosenblatt et al., 1992).
The biochemical consequences of cyclin binding to Cdks are not well understood, although it is known that binding of cyclins is a prerequisite for covalent modifications that are essential for catalytic activity (reviewed in Clarke, 1995; Morgan, 1995). For example, binding of an appropriate cyclin is required in order for Cdk-activating kinase (CAK) to phosphorylate T160 on Cdk2 and T174 on Cdk4 (Gu et al., 1993; Kato et a., 1994). The Cdks are inactive unless these carboxy-terminal threonine residues arc phosphorylated. Cyclin kinase inhibitors act in part to block CAK-dependent activation of Cdks (Gu et al., 1993; Kato et al., 1994; Slingerland et al., 1994), suggesting that cyclins and CKIs serve antagonistic functions with respect to CAK-dependent activation of Cdks.
Broadly speaking, there are two classes of metazoan CKIs. One class consists of the members of the INK family, which include but is probably not limited to p15, p 16, p18, and p19 (reviewed in Elledge and Harper, 1994; Hunter and Pines, 1994; Sherr and Roberts, 1995). INK type CKIs bind to and sequester Cdk4 and Cdk6, but not Cdk2. The sequestration of the Cdk subunit by these inhibitors prevents Cdk4 or 6 from complexing with its cyclin subunit (Serrano et al., 1993; Hannon and Beach, 1994). The INK type inhibitors also prevent Cdk4 and Cdk6 phosphorylation by dissociating the cyclin/Cdk binary complex which is the substrate for CAK. Activated cyclinD/Cdk4 complexes (i.e., those in which T174 has already been phosphorylated) are also inhibited due to displacement of the cyclin subunit by these inhibitors (reviewed in Elledge and Harper, 1994; Hunter and Pines, 1994; Sherr and Roberts, 1995).
The second family of CKIs, is comprised of Cip1 (also called WAF1, Cap20, and Sdi1) Kip1 and Kip2 (Harper et al., 1993; El-Deiry et al., 1993; Polyak et al., 1994; Toyoshima and Hunter, 1994). These CKIs bind to cyclin/Cdk binary complexes that contain Cdk2, Cdk3, Cdk4, or Cdk6 (reviewed in Elledge and Haper, 1994; Hunter and Pines, 1994; Sherr and Roberts, 1995). Unlike members of the INK family, Cip1 and Kip1 do not disrupt cyclin/Cdk complexes, but bind to such entities to form ternary and higher order complexes (Harper et al., 1993; Harper et al., 1995; Xiong et al., 1992, Zhang et al., 1993). Cip 1 and Kip1 are structurally related to each other, but not to the INK-type CKIs (Hannon and Beach, 1994; Polyak et al., 1994; Serrano et al., 1993; Toyoshima and Hunter, 1994). Both Cip1 and Kip1 have similar properties in vitro. Both inhibit phosphorylation by CAK at low stoichiometries, thereby preventing Cdk activation (Gu et al, 1993; Harper et al., 1993; Polyak et al., 1994; Toyoshima and Hunter, 1994). Cip1 appears to facilitate the formation of cyclin A/Cdk2 complexes at low concentrations of the inhibitor (Haper et al., 1995; Zhang et al., 1994), and it has been suggested that Cip1 may be involved in recruitment of cyclin A and Cdk2 to newly synthesized ternary complexes. At higher stoichiometries. Cip1 and Kip1 are potent inhibitors of activated Cdk2, Cdk3, Cdk4. and Cdk6 (Zhang et al., 1993: Gu et al., 1993; Harper et at. 1993). It is believed that Cip1 and Kip1 constitute an activation threshold for progression through the G1 phase of the cell cycle. According to this hypothesis. activation of Cdk2, Cdk4. and Cdk6 cannot occur until the abundance of the corresponding cyclin/Cdk complexes exceeds the concentration required to saturate the xe2x80x9cfreexe2x80x9d pools of Cip1 plus Kip1 (reviewed in Elledge and Harper, 1994; Hunter and Pines, 1994; Sherr and Roberts, 1995; Morgan, 1995).
The mechanism where by Cdks regulate cell cycle progression is complex and by no means complete. However, large amounts of data have been collected regarding how Cdks regulate transition from G1 into S phase. The majority of this work centers around the product of the retinoblastoma tumor suppressor gene, Rb. Rb functions in part by serving as a control point that connects extracellular signals and gene transcription. Rb is a phosphoprotein that is differentially phosphorylated throughout the cell cycle. During G0 or early G1, Rb is present in a hypophosphorylated form and exert its growth suppressive activity (reviewed in Weinberg, 1995; Nevins, 1992; Hinds and Weinberg, 1994). When Rb is present in this form it binds to and inactivates certain members of the E2F transcription factor family. The binding of Rb with E2F blocks E2F-mediated transcription of cellular genes that are required for entry into S phase, such as DNA polymerase ax, and dihydrofolate reductase (reviewed in Nevins, 1992; Farnham et al., 1993; Hinds and Weinberg 1994). G1 cyclin/Cdk complexes are believed to relieve this Rb-mediated suppression by phosphorylating Rb, which results in the release of E2F (Nevins, 1992; Weinberg, 1995). Upon its release E2F can then activate transcription of cellular genes essential for entry into S phase. A schematic of Cdk-mediated inactivation of Rb is shown in FIG. 2.
There is a substantial amount of data indicating that all G1 cyclin/Cdk complexes play critical roles in the initiation of and/or progression through S phase (reviewed in Draetta 1994; Elledge and Harper, 1995; Sherr, 1994), but until substrates besides Rb are found, the specific role for each cyclin/Cdk complex in regulating cell cycle progression will likely remain largely unknown. Anologous results are likely for other DNA viruses dependent on cell cycle stimulatory kinases for replication at least most other species-specfic CMV""s.
In vitro mammalian cell systems provide the most studied and best models for DNA virus infections. This is most spectacularly true for HCMV, where there is no accepted animal model. The well-studied in vitro HCMV systems provide a superior model for all mammalian DNA virus infections.
An important aspect of the present invention is a method for inhibiting proliferation of a DNA virus which is dependent upon events associated with cell proliferation for replication. The DNA virus include, for example any of the herpesvirus family such as Herpes simplex, e.g., and most particularly cytomegalovirus (especially human cytomegalovirus). The method involves administering a prophylactically or therapeutically effective amount of a cyclin-dependent kinase (e.g., Cdk2) inhibitor to a patient. The therapeutically effective amount of inhibitor is that amount sufficient to inhibit Cdk and therefore prevent viral replication. The most preferred inhibitor is roscovitine although olomoucine or other Cdk inhibitors are also acceptable. Once the knowledge of the present invention is available, many other Cdk inhibitors may be developed and these Cdk activity inhibitors will be useful for the therapy and prophylaxis of DNA viral infections. Herpesviruses such as herpes simplex, for example, are also treatable by the methods of the present invention. The preferred therapeutically or prophylactically effective amounts of the Cdk inhibitors of the present invention (e.g., roscovitine, olomoucine and the like) are about 0.1 xcexcg/kg body weight to about 1000 xcexcg/kg of body weight (more preferably 0.1 xcexcg/kg to 100 xcexcg/kg. However, more effective Cdk or Cdk2 inhibitors would have to be added at lesser concentrations. Likewise, weaker Cdk inhibitors would require greater amounts (i.e., 10-1000 xcexcg/kg). Other Cdk inhibitors may be readily developed and tested based upon the structures and assay methods described herein or well known to those of skill in the art.
Human cytomegalovirus is a herpesvirus that induces numerous cellular processes upon infection. Among these are activation of cyclin-dependent kinase 2 (Cdk2), which regulates cell cycle progression in G1 and S phase. Inhibition of cellular Cdk2 activity blocks HCMV replication. Inhibition of Cdk2 activity by roscovitine inhibits HCMV DNA synthesis, production of infectious progeny, and late antigen expression in infected cells in a dose-dependent manner. HCMV replication is also inhibited by the expression of a Cdk2 dominant negative mutant, whereas expression of wild type Cdk2 has no effect on viral replication. Activation of cellular Cdk2 is now found necessary for HCMV replication.
HCMV replication is particularly dependent on the activity of cyclin E-Cdk2. Drugs that inhibit the activity of Cdk2 profoundly inhibit virus replication. Drugs that block certain components in the proliferative activation of cells and their progression through the cell cycle also block HCMV replication. Other viruses, particularly DNA viruses and more particularly herpesviruses that are dependent on events activating cell proliferation for replication will be similarly inhibited.
As demonstrated herein. the administration of cytotoxically effective amounts of cdk2 inhibitors may also be used to selectively kill cells infected with a DNA virus such as HCMV, for example.
Administration of the Cdk inhibitors may be parenteral (intravascular, e.g.) enteral or topical (e.g., intracavitary). The topical intracavitary administration may be to any body cavity likely to be a scene for viral infection or to already possess infected cells.

Suppression of cyclin kinase 2 activity for prevention and treatment of DNA viral infections

Board of Regents, The University of Texas


A manual transmission mechanism adapted for use in an engine-driven automotive vehicle comprising a mainshaft and a countershaft, gearing arranged on each of said shafts, and synchronizer clutch structure which is arranged to accommodate a shift linkage mechanism for actuating the synchronizer clutch sleeve so the synchronizer clutch arrangement makes possible a location of the driver-operated shift linkage in close proximity to the synchronizer clutch sleeves and permits an efficient shift pattern for the driver-controlled shifter and a simplified assembly of the linkage mechanism.

My invention relates to a manual transmission having gearing adapted to establish multiple torque ratios in a driveline for an automotive vehicle as it distributes torque from an engine-driven shaft to a torque output shaft connected drivably to the vehicle traction wheels.
A preferred embodiment of my invention is adapted for use with a rear-wheel drive vehicle wherein the torque input shaft for the transmission is aligned with respect to the torque output shaft. As in the case of certain prior art manual transmissions, the present invention is adapted to establish five forward-driving ratios and a single reverse ratio.
An example of a transmission presently known in the prior art is illustrated in U.S. Pat. No. 4,222,281. This transmission comprises a mainshaft which is aligned with respect to a torque input shaft in parallel disposition with respect to a cluster gear shaft. The driven shaft is connected directly to the mainshaft.
Torque delivery gears in the transmission of the '281 patent are journalled on the mainshaft. These mesh with gear elements of the cluster gears of a cluster gear assembly supported on the countershaft. The gears on the mainshaft can be connected selectively to the mainshaft by synchronizer clutch mechanisms, each of which has a shiftable synchronizer clutch sleeve under the control of the vehicle operator. A linkage mechanism, which includes a shift cane, is mounted at the torque output side of the transmission at a remote location with respect to the gearing. A shift rail extends in a direction parallel to the axis of the mainshaft to transfer reciprocating and rotary motion of a driver-operated shift lever element to shift forks which, in turn, actuate selectively the synchronizer clutch sleeves.
The remote disposition of the driver-controlled shift lever with respect to the synchronizer clutch elements in the transmission of the '281 patent makes it necessary to provide a complex shift linkage arrangement. This introduces a transmission calibration problem during assembly because of stack-up tolerances that exist. The arrangement is further complicated by the fact that the motion of the shift lever is controlled by a shift gate and detent mechanism that are located on and supported by a stationary transmission housing independently of the mounting structure for the driver-controlled shift lever.
A manual transmission having a pair of countershafts is shown in prior art U.S. Pat. No. 4,033,200. Unlike the teachings of the prior art '281 patent, the transmission disclosed in the '200 patent has a pair of countershafts each of which supports torque transfer gearing under the control of synchronizer clutches. The mainshaft extends between the pair of countershafts, and the output gear is connected drivably through torque output gearing through the driven shaft as the torque input shaft receives torque from the engine.
A shift linkage mechanism for a transmission of the kind shown in the '200 patent is described in prior art U.S. Pat. No. 4,799,399. This includes synchronizer clutch sleeves that are actuated by synchronizer clutch forks carried by a shift rail. The motion of the shift rail is controlled by a driver-actuated shift lever. The pattern of the motion of the shift lever to accomplish the shifting movement of the shift forks is controlled by a gate and detent mechanism that is secured to a stationary transmission housing. A complex shift linkage mechanism is required to transfer the motion of the driver-actuated shift element to the synchronizer clutch sleeves. This includes a special shift linkage reversing mechanism for actuating a reverse-drive synchronizer clutch.
Prior art U.S. Pat. No. 4,338,828 shows a typical arrangement for establishing the shift path as a transmission shift control lever is actuated by the driver driving ratio selection. This includes a guide plate having a predetermined track and detent arrangement for defining axial positions and rotary positions of the shift rail that is controlled by the driver-operated shift lever.
Prior art U.S. Pat. No. 4,889,003 shows typical synchronizer clutch mechanisms including clutch sleeves for accomplishing ratio changes as torque is transferred through selected gearing supported by the mainshaft and by a countershaft in a transmission of the kind disclosed in prior art U.S. Pat. No. 4,799,399 discussed above.


An exposure method immerses, in liquid, a surface of an object to be exposed, and a surface of a projection optical system closest to the object, and projects a repetitive pattern formed on a mask via the projection optical system onto the object. The exposure method may direct exposure light having a wavelength λ through a projection optical system that is at least partially immersed in liquid and has a numerical aperture of no·sin θNA greater than 0.9 in order to transfer a pattern formed on a mask onto an object to be exposed, wherein no is a refractive index of the liquid, Δn is the fluctuation of the refractive index of the liquid, θNA is the largest angle common to the liquid and a resist material applied to the object to be exposed, and d is a thickness of the liquid in an optical-axis direction of the projection optical system which satisfies d≦(0.03λ) cos θNA/Δn.

The present invention relates generally to an exposure method and apparatus used to fabricate various devices including semiconductor chips such as ICs and LSIs, display devices such as liquid crystal panels, sensing devices such as magnetic heads, and image pick-up devices such as CCDs, as well as fine contact hole patterns used for micromechanics, and more particularly to a so-called immersion type exposure method and apparatus that immerse, in liquid, a surface of an object to be exposed, and a bottom surface of a projection optical system closest to the object, and expose an object via the liquid.
Reduction projection exposure apparatus has been conventionally employed which use a projection optical system for projecting a circuit pattern formed on a mask (reticle) onto a wafer, etc. and for transferring the circuit pattern, in manufacturing such fine semiconductor devices as semiconductor memories and logic circuits in the photolithography technology.
The critical dimension transferable by the projection exposure apparatus is proportionate to a wavelength of light used for exposure, and inversely proportionate to the numerical aperture ("NA") of the projection optical system. The shorter the wavelength is, the better the resolution is. Smaller resolution has been demanded with a demand for finer semiconductor devices. The exposure light is requested to move to small wavelength, and the projection optical system is expected to improve resolution using higher NA. Because of the difficulty of changing the exposure wavelength, a projection optical system has accelerated an improvement of its NA; for example, a projection optical system having NA=0.9 has been developed.
On the other hand, light sources for the exposure apparatus have changed from a KrF laser (with a wavelength of 248 nm) to an ArF laser (with a wavelength of 193 nm). At present, an F2 laser (with a wavelength of 157 nm) and EUV (with a wavelength of 13.5 nm) have been developed as next generation light sources.
In such a situation, immersion exposure has called attentions, as disclosed in Japanese Patent Publication No. 10-303114, as a method that uses ArF laser (with a wavelength of 193 nm) and F2 laser (with a wavelength of 157 nm) for improved resolution. The immersion exposure uses a liquid as a medium at a wafer side. It fills the space between the projection optical system and a wafer, to promote a higher NA. Specifically, the projection optical system has a numerical aperture ("NA") of n·sin θ, where "n" is a refractive index of the liquid, and NA can increase up to "n".
Influence of polarized light on imaging performance becomes non-negligible as NA becomes higher and higher, because the imaging performance becomes different according to polarization directions as the light has a larger incident angle upon a wafer.
The performance for two-beam imaging is much more affected by polarization than that for three-beam imaging. In the three-beam imaging that forms an image through interference among three beams, i.e., the 0th order beam and the ±1st order diffracted beams, an angle does not reach 90° between the 0th order beam and the 1st order diffracted beam and between the 0th order beam and the −1st order diffracted beam, which form a basic frequency for imaging, and the influence of polarization does not appear significantly. On the other hand, two-beam imaging includes the interference between two 1st diffracted beams and that between the 0th order light and one of the ±1st order diffracted beams. The influence of polarization on the imaging performance is serious because two beams that form the basic frequency have large angles.
Moreover, in the immersion case, two-beam imaging can problematically meet a condition in that no image is formed at all in a certain polarized light direction. This phenomenon has not occurred in a conventional non-immersion optical system. When two interfering beams are supposed to form an image as shown in FIG. 16A, p-polarized beams with a polarization direction on the paper surface do not interfere with each other or do not contribute to imaging because they form an angle of 90°. When two beams are in symmetry and form an angle of 90°, an incident angle is 45° and sin 45°32 0.7.
On the other hand, s-polarized beams shown in FIG. 16B have a polarization direction orthogonal to the paper surface and form an image with good contrast. This fact now defines a polarization direction that forms an image with good contrast as an s-polarized component or s-polarized light. As discussed, the s-polarized light has a polarization direction orthogonal to the paper surface when two beams interfere with each other on the paper surface. The polarization direction has implications with a direction in which a pattern is formed. When an interference fringe is formed by two beams, a direction of s-polarized light accords with each longitudinal direction of an interference fringe formed by two beams: An X direction is a direction of the s-polarized light in forming an interference pattern whose fine structure extends in the X direction. A Y direction is a direction of the s-polarized light in forming an interference pattern whose fine structure extends in the Y direction.
When two-beam interference is considered which forms an image through interference between two beams having angles of ±θr in resist, where no is a refractive index of a medium between a projection optical system and the wafer, θo is an angle in the medium, and nr is a refractive index of the resist, Equation (1) below is established from the Snell's law:nr·sin θr=no·sin θo  (1)
When the medium is the air, Equation (2) below is established since no=1 and sin θo<1:nr·sin θr=no·sin θo<1  (2)
In the case of ArF excimer laser, the resist typically has a refractive index nr=1.7, and Equation (2) leads to sin θr<0.59. Thus, when the medium is the air, the angle θr in the resist never shows sin θr=0.7. The cross angle of 90° condition in resist, consequently, never occurs.
On the other hand, in the case of immersion where the medium is liquid, Equation (3) below is established. When the medium has a refractive index no=1.47:nr·sin θr=no·sin θo<1.47  (3)
Since the resist usually has the refractive index nr=1.7, sin θr<0.86. Thus, when the medium is liquid, θr can attain the condition sin θr<0.7.
Again, a condition never meets sin θr<0.7 when the medium is the air, whereas a condition can meet sin θr<0.7 when the medium is liquid, whereby the p-polarized light does not interfere and the contrast from the p-polarized light becomes zero. When the illumination light is non-polarized, only the s-polarized light, which is the half of the incident light, contributes to imaging. The p-polized light does not contribute to the imaging, thus halving the contrast, and creating a reduced contrast problem.
For example, in the case of ArF excimer laser, Equation (4) below is established when the medium is water and no=1.47:
                              sin                                                                          θ            o                          =                                                            n                r                                            n                o                                                  sin                                                                                θ              r                                =                                                    1.7                1.47                                          sin                                                                                45                ∘                                      =            0.81                                              (        4        )
As a consequence, water as the medium causes a condition that provides no interference of p-polarized light when sin θo=0.81. Thus, the p-polarized light does not form an image when an incident angle in the medium approximately meets sin θo=0.8. This problem is inevitable since an optical system for immersion is required to have super-high NA, which means much larger than 1.0. In this case, the angle in the medium meets sin θo=0.8. Even in case of F2 excimer laser, the similar relationship is established when sin θo is approximately 0.8 since the medium has a refractive index of around 1.36 and the resist has a refractive index of 1.5 or higher.
It is known that increased refractive indices of the resist and liquid are effective to increase NA. The resist and liquid have different refractive indices according to their materials. As disclosed in U.S. Pat. No. 4,346,164, a small difference of refractive index between the resist and liquid is preferable, but, in the usual case, sinOr in the resist is slightly smaller than sin θo in the medium. The inventors have discovered that since it is anticipated that the resist for exclusive use with the immersion will be developed, it is preferable to set sin θo in the medium in the exposure apparatus side to be approximately equivalent with sin θr in the resist. Thus, the condition that provides no interference of p-polarized light may be regarded as sin θo≈sin θr=0.7.
As discussed, the high NA projection optical system is necessary for finer patterns, while the imaging performance deteriorates due to the p-polarization features of the high NA imaging beam. In some cases, the desired pattern cannot be formed as is predicted by the simple scalar theory, which does not count the polarization effect.


A method of preparing a catalyst having the elements and the proportions indicated by the following empirical formula: EQU VSb.sub.m A.sub.a D.sub.d O.sub.x. where PA1 A is one or more Ti, Sn, where Sn is always present PA1 D is one or more Li, Mg, Ca, Sr, Ba, Co, Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, As, B, Al and Mn wherein PA1 m is 0.5 to 10 PA1 a is greater than zero to 10 PA1 d is zero to 10 PA1 x is determined by the oxidation state of the cations present,. comprising making an aqueous slurry of a mixture of source batch materials comprising compounds of said elements to be included in the final catalyst, followed by drying and heat calcining the mixture to an active catalyst, wherein the source batch material for the tin is a solution which comprises SnO.sub.2.xH.sub.2 O wherein x.gtoreq.0 dispersed in tetraalkyl ammonium hydroxide wherein the tetraalkyl ammonium hydroxide is defined by the following formula: EQU C.sub.n H.sub.2n+1 NOH. wherein 5.gtoreq.n.gtoreq.1,. drying said slurry and calcining the mixture to an upper calcination temperature of at least 500.degree. C.

1. Field of the Invention
This invention relates to a method for the preparation of tin-containing vanadium-antimony oxide catalysts useful for the catalytic ammoxidation of C.sub.3 to C.sub.5 paraffins or olefins, more specifically for the preparation of catalysts for the ammoxidation of propane or isobutane or propylene or isobutylene to its corresponding .alpha.,.beta.-unsaturated mononitrile, acrylonitrile or methacrylonitrile. In addition, the catalyst may be used in the ammoxidation of methylpyridine, m-xylene or the oxidation of o-xylene to cyanopyridine, isophthalonitrile or phthalic anhydride, respectively.
More specifically, the invention relates to the use of a SnO.sub.2.xH.sub.2 O wherein x.gtoreq.0 dispersed in a solution of a tetraalkyl ammonium hydroxide as the reagent for tin in the preparation of catalysts containing vanadium and antimony and tin in oxide form. These types of catalysts are disclosed for instance in U.S. Pat. Nos. 3,681,421, 4,788,317, 5,008,427 and in British specifications 1,336,135 and 1,336,136, published in November 1973.
Not all sources of tin are equally effective as promoters in vanadium-antimony oxide catalysts for the oxidation and ammoxidation of saturated C.sub.3 and C.sub.4 alkanes, particularly ammoxidation. In fact, U.S. Pat. No. 5,214,016 and EPO 691306-A1 teach that the source of tin promoter is critical to the performance characteristics of the finished catalyst. It is believed that the tin should be present in very finely divided form in the precursors of such catalysts in order for the tin to be fully reactive when the solid state reaction takes place upon calcination of the catalyst precursor mixture. Tin oxide sol is a suitable source in making catalysts of the present invention; see U.S. Pat. No. 5,008,427. However, ground tin oxide or tin oxide made by reacting tin metal with nitric acid are decidedly less effective sources in catalyst preparation. While current commercially available tin oxide sol is effective, it has a serious disadvantage because it is a very expensive source.

Preparation of vanadium antimonate based catalysts using SnO.sub.2 .multidot.xH.sub.2 O


A location display apparatus has a display section for displaying a location and voice-synthesizes the location in response to a DTMF signal received from a circuit so as to transmit a corresponding message to the circuit. Moreover, in accordance with received DTMF signals, a power source of the apparatus is controlled, the message is transferred, and the displayed location is changed.

1. Field of the Invention
The present invention relates to a location display apparatus which can change a displayed destination or location via a telephone line so that a person is able to inform his/her office of a change in destination or location from a remote area.
2. Description of the Related Art
In the conventional nonelectronic practice, a bulletin board or a so-called white board may be utilized to indicate the location of personnel in terms such as name and visiting destination, etc. Each person writes a destination on the white board using a marker pen, etc. before leaving for the destination. However, in this conventional location display apparatus, the displayed location information cannot be changed from a remote area. Moreover, if one person wishes to confirm a location of another person, he is inconveniently obliged to go to the site where the white board is provided.


An apparatus for testing a defect, includes a semiconductor element. In the semiconductor element, a conductive film is formed on an STI (shallow trench isolation) insulating film, which fills a shallow trench extending into a semiconductor region, opposing said semiconductor region through an insulating film in an ordinary state, and the shallow trench is not completely or sufficiently filled with the STI insulating film in a defective state. Also, the apparatus includes a control circuit configured to set a test mode in response to a test mode designation signal, a first voltage applying circuit configured to output a first voltage to the conductive film in the test mode, and a second voltage applying circuit configured to output a second voltage to the semiconductor region in the test mode. The first voltage is higher than the second voltage, and a voltage difference between the first voltage and the second voltage is sufficient to cause breakdown between the conductive film and the semiconductor region in the defective state.

1. Field of the Invention
The present invention relates to an apparatus and method for testing reliability of a trench-type device isolation insulating film of a semiconductor device.
2. Description of the Related Art
In semiconductor devices such as a nonvolatile memory, in which a large number of elements are formed and arrayed on a semiconductor substrate, a trench-type device isolation insulating film, e.g., a shallow trench isolation (STI) film is provided to insulate and isolate the elements from one another. The trench-type device isolation insulating film is formed by forming trenches in a semiconductor substrate to a predetermined depth and by filling the trenches with insulating films. For example, FIG. 3 is a block diagram showing a flash memory with a memory cell array MA in which a large number of memory cells M are arranged in a matrix. The memory cells M arranged in a row direction are connected with a control gate CG as a word line WL extending in the row direction. The memory cells M arranged in a column direction are connected with a bit line BL extending in the column direction. The word lines WL are connected to a word decoder WD, which selects one of the word lines based on a row address. Similarly, the bit lines BL are connected to a bit decoder BD, which selects one of the bit lines based on a column address.
FIGS. 1A and 1B are schematic cross sectional views showing the memory cells M of the flash memory. Specifically, FIG. 1A is a cross sectional view of the memory cells arranged in the row direction, and FIG. 1B is a cross sectional view of the memory cells arranged in the column direction. Trenches 106 are formed in a predetermined pitch in the row direction in the surface portion of a well WELL formed in a semiconductor substrate 101. Drain regions D 109 and source regions S 110 are formed in the surface portion of the well WELL between the trenches 106. In addition, a tunnel oxide film 102 is formed on the surface of the well WELL, and a floating gate film 103 as a floating gate FG is formed on the tunnel oxide film 102. An insulation film 111 is formed to fill the trench 106 in the thickness direction to a middle height of the control gate FG. Thus, a trench-type device isolation insulating films (STI films) 112 are formed for the floating gate CG to be insulated and isolated from each other. Also, a capacitive insulation film 107 is formed on the floating gate FG, and a control gate film 108 for a control gate CG is formed on the capacitive insulation film 107 and serves as a word line WL extending in the row direction.
FIGS. 2A to 2C show a manufacturing method of the STI films and the memory cells. As shown in FIG. 2A, a tunnel oxide film 102, a floating gate film 103, a buffering oxide film 104, and a nitride film 105 serving as polishing stopper film 105 are sequentially formed on a well WELL in the semiconductor substrate 101. Subsequently, these films and the semiconductor substrate 101 are selectively etched, to form the respective trenches 106 of a predetermined depth. Next, as shown in FIG. 2B, an insulating film 111 is deposited to fill the trenches and to cover the nitride film 105. Subsequently, as shown in FIG. 2C, the insulating film 111 is polished by a chemical mechanical polishing (CMP) method by using the nitride film 105 as a stopper, to flatten the surface of the insulating film 111. Then, the nitride film 105 and the oxide film 104 are etched, and the surface of the insulating film 111 is etched. Thus, the insulating film 111 is remains only in the trenches 106, and the STI film is formed. Subsequently, the capacitive insulating film 107 and the control gate film 108 are formed on the STI film in order, and these films are patterned into a predetermined pattern. Subsequently, impurity is ion-implanted to form the drain regions 109 and the source regions 110. Thus, the STI films 112 and the memory cells M shown in FIGS. 1A and 1B are formed. Such an STI film manufacturing method is disclosed in Japanese Laid Open Patent Application (JP-P2002-110780A).
According to the STI film manufacturing method, as shown in FIG. 2B, there is a case that the certain trench 106 is not completely or sufficiently filled with the insulating film 111 due to foreign substance Z. In such a case, a void V is produced in the trench 106 when the insulating film 111 is polished. Consequently, the capacitive insulating film 107 and a part of the control gate film 108 are formed in subsequent steps, to fill the inside of the trench 106, as shown in FIG. 2C. Thus, the control gate film 108 is formed to oppose to the well WELL of the semiconductor substrate 101 through only the thin capacitive insulating film 107. Specifically, the control gate CG is in contact with the well WELL through only the thin capacitive insulating film 107.
By the way, referring to FIGS. 1A and 1B, and 4, a writing operation into the memory cell of the above-described type will be described. In case of the writing operation, a voltage VCG of the control gate CG is set to a positive voltage of about 9 V, and a voltage VWELL of the semiconductor substrate 101 is set to a GND (ground) potential of 0 V. Also, in case of an erasing operation, a negative voltage VCG of about 9 V is applied to the control gate CG, and a positive voltage VWELL lower than +9 V is applied to the well WELL. Therefore, electric field stress of about 9–18 V as a voltage difference between the control gate voltage VCG and the well voltage VWELL is applied to the capacitive insulating film 107. In case of the semiconductor device in which the trench 106 is appropriately filled with the insulating film 111 serving for the STI film 112, the electric field stress is applied through the insulating film 111 and the capacitive insulating film 107 to the STI film 112. In this case, therefore, the STI film 112 has a sufficient endurance. However, in case of the semiconductor device in which the trench 106 is not sufficiently filled with the insulating film 111, as shown in FIG. 2B, there is only the thin capacitive insulating film 107 between the control gate CG and the well WELL. In this case, therefore, deterioration of the capacitive insulating film 107 advances when the electric field stress is repeatedly applied. Finally, electrical leakage or breakdown X occurs between the control gate CG and the well WELL, and causes a memory operation fault.
In order to prevent delivery of a semiconductor device having a possible operation fault, it is preferable to carry out a test where the writing/erasing operations are repeated. However, such a test method requires a long test time. Also, if the number of times of the writing/erasing operations is not appropriate, there is a possibility that a semiconductor device having the possible operation fault may be delivered. In such a case, deterioration of the capacitive insulating film could further advance through a final product test and the actual use of the semiconductor device by an end user, resulting in the semiconductor device being regarded as a defective product. As a result, reliability of the manufacturer side will be lost.

Method and apparatus for testing defective portion of semiconductor device


Aspects of the disclosure provide a circuit that includes a decoder, an error checking module, and a controller. The decoder is configured to receive codewords, and decode the codewords based on an error correcting code. The error checking module is configured to error-check sectors using an error detecting code in the sectors. Each sector is formed of a plurality of decoded codewords. The controller is configured to store in a memory, when the error checking fails for at least one sector, the decoded codewords and corresponding flags indicative of pass or fail of the decoding of the codewords.

The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Generally, data stored on an optical disc is encoded with error detecting code and/or error correcting code. The error detecting code can be used to detect errors, and the error correcting code can be used to correct certain errors.

This patent is subject to a terminal disclaimer.


In embodiments, a semiconductor package may include a first die and a second die. The package may additionally include a serializer/deserializer (SerDes) die coupled with the first and the second dies. The SerDes die may be configured to serialize signals transmitted from the first die to the second die, and deserialize signals received from the second die. Other embodiments may be described and/or claimed.

Many modern applications may require wide bus (e.g., 1000+ signal) interconnects between chips. The large number of signals may drive the bump pitch between the dies used in the interconnects, as well as the pitch of connections between the dies and the package. In legacy packages, the bump pitch may be on the order of approximately 20 to 30 micrometers ("microns" or "μm") for die-to-die interconnects. The die-to-package interconnect pitch may be on the order of approximately 80 to 100 microns. As a result, for 1000 signals, the area needed on a die to accommodate pitches of this scale may be on the order of approximately 10 millimeters squared (mm2) for a 100-micron pitch and approximately 0.9 mm2 for a 30-micron pitch.
As technology advances, the number of signals needed for the bus may increase. For example, the bus may need to be able to enable higher data rates, wider data bus memory, etc. As a result, the area needed to send all of the signals off the die may proportionally increase. In legacy package, this increase may result in larger die sizes (And thus higher cost); added latency due to the longer distances the signals may have to travel across the die and to fan out with relatively high resistive-capacitive (RC)-delay lines; and higher power requirements because the signals may need to be re-clocked if the travel long enough distances.

Serializer-deserializer die for high speed signal interconnect


A method of polishing workpieces in a magnetic float polishing chamber comprising a lower chamber piece and an upper chamber piece which is removably receivable in the lower chamber piece and is connected to a powered spindle for rotating the upper chamber piece in the polishing operation. The method preferably comprises one or more of the steps of (a) geometrically aligning the upper chamber piece with the powered spindle by machining the upper chamber piece in-situ, (b) machining the contact surface of the upper chamber piece in-situ between various polishing runs, and (c) mounting the lower chamber piece in a manner effective for causing the lower piece to automatically self-align coaxially with the upper chamber piece.

Traditional rolling element bearings made from AISI 52100 bearing steel or M50 high-speed steel are limited in performance for use at very high speeds, high temperatures, and corrosive environments. They need adequate lubrication for satisfactory operation and optimum life. Over the past decade or so, silicon nitride (Si3N4) balls have become an important component in advanced bearings. They are most successfully used in hybrid bearings (SNHB). Si3N4 is typically the preferred material because it offers many desirable properties, such as high hardness, high thermal and chemical stability, low density, high Young's modulus, high stiffness, good fatigue life, low friction, and high wear resistance.
The lower density of Si3N4 balls reduces the gyroscopic slip and centrifugal loading on the outer steel race. This reduces friction, heat, and wear of the bearing elements. Si3N4 balls do not react with the steel race and hence, micro-welding can be avoided resulting in longer bearing life. SNHB are well suited for applications where marginal lubrication is required and are less sensitive to the lubricant type, lubricant contamination, and lubricant starvation. Higher rigidity, excellent surface finish and sphericity of Si3N4 balls reduces noise and vibrations of these bearings, thus enabling higher speeds.
The benefits listed above make Si3N4 hybrid bearings (SNHB) suitable for high speed and high temperature applications, such as turbines, machine tool spindles, dental drills, liquid oxygen pumps, and turbo molecular pumps. All-ceramic bearings (Si3N4 balls in Si3N4 races), on the other hand, can operate at higher temperatures, far outside the range of SNHB (−40 to +200° C.). They perform well in aggressive environments such as semiconductor processing, infrared missile seekers, and tidal flow meters. However, their use is limited mainly due to the difference in the thermal expansion coefficient between the metal drive shaft and the inner ceramic race, and hence, SNHB are preferred for most other applications.
Compared to traditional steel bearings, SNHB, in general, can more easily meet the requirements of higher efficiency, higher reliability, higher accuracy, higher speed, greater stiffness, longer life, lower friction, corrosion resistance, marginal lubrication, and lower maintenance costs.
The failure mode of Si3N4 balls is by fatigue flake-off which is similar to metallic rolling elements due to its higher fracture toughness. The performance and reliability of ceramic rolling element bearings depend on the quality of the resulting surface. Ceramics have high hardness and inherent brittleness. They are sensitive to defects resulting from grinding and polishing processes. Fatigue failure begins at regions of surface irregularities, such as scratches, pits, and microcracks. Hence, it is important to produce superior quality and finish with minimum defects in order to obtain reliability in performance.
In industry, ceramic balls have heretofore been finished by conventional grinding followed by V-groove lapping. This is essentially the same technique used for finishing steel balls. The balls run in 3-point contact in a V-groove. The balls revolve around the pad and at the same time rotate continuously. They glide and roll relatively against the contacting surfaces of the pad. The process uses high loads (about 10 N per ball), low polishing speeds (about 50 rpm), and a diamond abrasive. Due to lower speeds, considerable time (6-16 weeks) is required for finishing a batch of ceramic balls from the as-received condition to the finished condition. Thus, the long processing time and the use of expensive diamond abrasive result in high processing costs. Furthermore, the use of a diamond abrasive under heavy loads can result in scratches, pits, and microcracks on the surface and subsurface of the polished balls. These surface defects can act as nucleation sites for cracks resulting in catastrophic failure by large brittle fracture.
In order to prevent such failures, it is necessary to minimize the surface damage as much as possible. For this purpose, gentle polishing conditions are required, namely, a low level of controlled force and abrasive which are not significantly harder than the work material. High material removal rates and shorter polishing times can be obtained using high polishing speeds. This is accomplished by a process known as magnetic float polishing (MFP).
MFP processes typically use low loads (about 1 N per ball), high speeds (about 2000 rpm with a 2.5 inch diameter upper part of the chamber in the small batch apparatuses and about 500 rpm with a 12.2 inch diameter upper part of the chamber in large batch apparatuses), and abrasives such as B4C, SiC, and CeO2. For ¾ inch ceramic balls, a typical small batch apparatus will process a batch of about six balls whereas a large batch apparatus will typically hold a batch of about 46 balls. Similarly, 10 balls of ½ in. diameter and 15 balls of ⅜ in. diameter can typically be finished by a small batch apparatus as compared to about 69 balls of ½ in. diameter and about 104 balls of ⅜ in. diameter in the large batch apparatus. An actual polishing time of 20-30 hours is typically required to finish a batch from the as-received condition.
The processing time is not affected by the number of balls used in a given apparatus. For example, a modified float chamber having multiple ball tracks or rows can take 100-200 balls of ¾ in. diameter instead of 46 used in the single track apparatus, and yet, it will take about the same amount of time to polish them.
Magnetic float polishing MFP is based on the magneto-hydrodynamic behavior of a magnetic fluid that can levitate all non-magnetic materials suspended in it. A bank of permanent magnets (Nd—Fe—B) is arranged with alternate N and S poles below an aluminum chamber filled with the required amount of magnetic fluid and an appropriate abrasive (5 to 10% by volume). The magnetic fluid (also called ferrofluid) is a colloidal dispersion of extremely fine (100 to 150 Å) sub-domain ferromagnetic particles, usually magnetic (Fe3O4) in a carrier fluid, such as water or hydrocarbons (e.g., kerosene). Water in the magnetic fluid not only acts as a coolant but also participates in the chemical reaction with the work material during the polishing process. The ferrofluids are made stable against particle agglomeration by the addition of surfactants.
When a magnetic field is applied, the Fe3O4 particles are attracted downwardly towards the area of higher magnetic field and a resultant upward buoyant force is exerted on all of the non-magnetic materials, to push them upwardly toward the area of lower magnetic field. The abrasive grains, ceramic balls, and the acrylic float inside the chamber, all being non-magnetic materials, are levitated by the magnetic buoyant force.
The magnetic float polishing chamber is preferably installed in and operated using a machining tool (e.g., a Bridgeport vertical machining center). An upper piece of the polishing chamber is lowered into a lower chamber piece to make contact with the balls and to press them down to reach the desired level of force or height. A piezoelectric dynamometer, placed between the chamber and machine tool table, is used to measure the exact loading. The balls are polished by the abrasive grains under the action of the magnetic buoyancy levitational force when the upper piece of the polishing chamber is rotated by the machine tool spindle. A damage-free surface on ceramic balls is expected by the magnetic float polishing technique because the magnetic buoyant force (typically about 1 N/ball) is applied via a flexible acrylic float positioned in the polishing chamber beneath the workpieces. The function of the acrylic float is to produce a uniform, larger polishing pressure. A urethane rubber sheet is glued to the inner guide ring of the polishing chamber to protect it from wear. The material of the upper piece of the chamber is non-magnetic, austenitic stainless steel.
Once the balls are reasonably uniform in size, uniform removal of material from the ball surface is essential for obtaining good sphericity. Heretofore, this has been particularly problematic in large batch apparatuses, especially with large balls having large surface area, which increases as the square of the diameter of the balls. The apparatus and set up procedures currently used in the art are not capable of consistently and efficiently achieving the precise required geometric alignment and coaxially of the upper and lower polishing chamber pieces with each other and with the powered machine tool spindle.
The coaxiality of the upper piece of the polishing chamber with the machine tool spindle is particularly important but has been very difficult to accomplish. Heretofore, the upper chamber piece has been formed using precision machining techniques and then secured to the drive spindle of the machine used for the ball polishing operation.
Establishing and maintaining coaxiality between the upper and lower pieces of the polishing chamber has proved to be even more difficult to achieve and is one of the most significant factors affecting the results. If the upper and lower pieces of the polishing chamber are not aligned properly, unequal loading will result, which will cause higher material removal rates at areas of higher loading. This means that, as a ball circulates around the chamber, some areas of the ball's surface will be machined more than others, thereby severely degrading the ball's sphericity. Also, this unequal loading is a source of vibration, which again has the same effect.

Method and apparatus for magnetic float polishing

The Board of Regents for Oklahoma State University


A golf club head (1) whose volume is delimited by a crown (3), a sole-plate (11), a belt (4), and a hitting surface (2), junctions between the belt (4) and the hitting surface (2) delimiting a heel (9) and a toe (10). The belt (4) comprises at least one arc-shaped portion (8, 32, 33, 34, 35) which forms a visible layer of the belt (4), while extending along the belt (4) between the heel (9) and the tip (10), the arc-shaped portion (8, 32, 33, 34, 35) being a peripheral weight made of a high-density material.

The invention relates to the field of golf and, more particularly, to golf club heads.
Each club must enable a player to impart to the ball a long, precise trajectory. The distance traveled by the ball increases as the dynamic loft of the club head becomes greater, and trajectory accuracy improves as a function of head stability at the moment of impact on the ball. For this reason, manufacturers seek to improve the mechanical inertia of the heads.
Traditionally, golf club heads possessed homogeneous density; that is, they were made of solid wood or metal. These heads were difficult to use because of their low mechanical inertia. When a stroke was poorly aligned, the ball traveled substantially off-line.
Next appeared hollow heads made of metal or composite materials. These heads provided greater mechanical inertia for a given weight, thereby improving the golfers' performance.
However, despite the various prior art solutions to achieve optimal distribution of the weight of the head, many golfers still had difficulty hitting their shots properly.
Current heads do not make it possible to obtain ball trajectories that are simultaneously long and precise. In other words, present-day heads do not incorporate weight distribution capable of providing at the same time good dynamic loft and good stability upon impact.


A trunk piston marine engine lubricating oil composition for a medium-speed compression-ignited marine engine comprises, in a major amount, an oil of lubricating viscosity containing 50 mass % or more of a Group II basestock, and, in respective minor amounts, (A) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of 4.5 or less, and (B) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent having a basicity index of greater than 4.5. The ratio of detergent (A) to detergent (B), both expressed as mass of active ingredient, is in the range from 0.5 to 15. The trunk piston marine engine lubricating oil composition has a TBN (using ASTM D2896) of 20 to 60.

The use of metal detergents in trunk piston engine oils (TPEO's) is well known and is described in the art. See, for example, U.S. Pat. No. B2-7,053,027. In "The Benefits of Salicylate Detergents in TPEO Applications with a Variety of Base Stocks", Proceedings of the 7th International Symposium on Marine Engineering, Tokyo, Oct. 24 to 28, 2005, criteria for the selection of the best detergent for TPEO's are discussed. The paper states that there is a move towards the use of more Group II base oils in marine lubricants in various regions of the world, based on availability and cost.
The paper concludes that salicylate has advantage over other other detergents as an asphaltene dispersant in both Group I and Group II base stocks. However, in section 1.4, the paper states that overbased detergents show lower stability in Group II oils.
The present invention ameliorates the stability problem in Group II oils by employing specific ratios of overbased metal carboxylate detergents of defined basicity index.


Provided is a wide field of view head mounted display device capable of presenting 120 degree field of view per one eye and 180 or more by both eyes horizontally while keeping resolution at least to the same extent of the conventional art. The wide field of view head mounted display device includes: a LCD 1 for displaying an image; a lens 2 for projecting an image displayed on the LCD 1; and a catoptric system with a concave mirror 4 and a convex mirror 3. The LCD 1 and the lens 2, the concave mirror 4 and convex mirror 3 are positioned in a relative relationship to observe by an observing pupil 5 at a predetermined position a virtual image of a beam of reflected light as an incident light on the concave mirror 4 when the light of displayed image on the LCD 1 is projected to the convex mirror 3 through the lens 2 and a reflected light of the projected light at the convex mirror 3 arrives as the incident light at the concave mirror 4.

1. Field of the Invention
The present invention relates to an image display device, more particularly to a head mounted display device.
2. Description of Related Art
In conventional arts, various types of head mounting devices (HMD) have been proposed, as shown in "Journal of Nippon Virtual Reality Society"; "Special issue on HMD", December 1998, Vol. 3, No. 2, pages 5 to 41, for example. They are largely classified in two types: one is an eyepiece optical type comprising a display element and eyepiece lenses that magnifies it directly; another is an eyepiece relay type by which a displayed image is focused once by a relay optical system and then the imaging surface is magnified by an eyepiece lens system. Eyephone 02 sold by VPL Company magnifies and displays an LCD (liquid crystal display element) in 86,000 pixels and thereby realizes 80 degree of the field angle for the purpose of wider field angle. However, the LCD in 86,000 pixels is not sufficient in view of resolution.
Further, other devices are proposed such as a device with 50 degree of the field angle by eccentric optical system in which a concave mirror is used and a device developed by Canon Corporation that realizes 43.5 degree of the field angle by an eyepiece relay system in which a free curved prism is used for a mirror. Olympus Optics Company also realizes 80 degree of the field angle for which a sheet of eccentric concave mirror is used. Further, Datavisor 80 by N-Vision Company as a HMD with wide field of view and high resolution realizes 80 degree in one eye and 120 degree in both eyes of the field of view. Also other example realizes 100 degree of the field of view by using two LCDs for one eye.
An example in Nara, Ifukube, Ino, Takahashi, and Yamamoto: "Affect on posture control by sight movement stimulus by wide field of view HMD" in papers of Nippon Virtual Reality Society, 1996, Vol. 1, pages 33 to 39 realizes 140 degree of the field of view by an eyepiece optical system by using two LCDs for one eye. However, it is said that field of view of human is 150 degree by one eye and 180 degree or more by both eyes horizontally. Therefore, the conventional studies mentioned above have not offered sufficient field of view.
An example in Inami, Kawakami, Yanagida, Maeda, and Tachi: "Wide field view stereoscopic display by Maxwell optical system" in papers of Nippon Virtual Reality Society, 1999, Vol. 4, No. 1, pages 287 to 294 realizes 110 degree of the maximum field of view in one eye by Maxwell optical system in which a half mirror and concave mirror are used, thereby wider field is given in comparison with the conventional art mentioned above. In this optical system, however, has a problem that, since a diameter of pupil affects the field of view, the brighter becomes a light source, the narrower becomes the field of view because of contraction of the diameter of the pupil.

Wide field of view head mounted display device


A method of removing noise from a color digital image, including receiving an original color digital image including a plurality of pixels represented in a primary-color space; producing at least one residual digital image and at least one base digital image from the original color digital image, the base digital image having a lower spatial resolution then the original color digital image; producing a noise reduced base digital image by removing noise from the residual image and the base digital image with a noise reduction filter and combining the noise reduced base digital image with the noise reduced residual image to produce a reconstructed digital image having reduced noise; transforming the reconstructed digital image into a luminance-chrominance color space; repeating the above process to produce a reconstructed luminance-chrominance digital image; and transforming the reconstructed luminance-chrominance digital image into a noise reduced digital image in the original primary color space.

There are many approaches to reducing the presence of noise in digital images. In order to minimize the required amount of computing resources needed, most commercial approaches to noise reduction in digital images are based on using very small regions of the image for each set of noise reduction computations. One of the simplest approaches with practical value is to use a 3×3 square region of pixels centered on the pixel to be noise reduced. This region is known in the literature as a pixel neighborhood or a support region. With only nine pixel values in the neighborhood available for computational purposes, a variety of algorithms can be used for producing a noise-reduced pixel value without undue burden on most computational resources. If the predominant nature of the noise signal being reduced consists of isolated erroneous pixel values, this pixel neighborhood size is generally sufficient for most noise reduction schemes. If the noise signal is more complex, however, and has clumps of erroneous pixel values that are several pixels wide in extent, the 3×3 square region of pixels will probably be insufficient for adequate noise reduction. The 3×3 square region will still permit the reduction of isolated erroneous pixel values, but will be largely ineffective on larger clumps of noise, especially if said clumps are larger than the 3×3 square region itself. The obvious solution is to increase the size of the noise reduction support region. This is generally a viable alternative up to the point at which the additional burden on the computational resources becomes unacceptable. Unfortunately, it is common for the computational limits of the system to be reached before the support region has been allowed to expand to the desired dimensions for adequate noise reduction.
A solution to these computational limitations is to decompose the image to be noise reduced into a series of images with varying spatial resolutions. In the literature this is described as performing a Laplacian pyramid decomposition. The process is simple. The starting image at its initial spatial resolution is referred to as a base image. A copy of the base image is blurred and then subsampled to a lower resolution. This lower resolution image is a new base image at the next level of the pyramid. This process can be repeated until there are insufficient pixels for any subsequent subsampling operation. A residual image is associated with each base image. In order to create the residual image for a given level of the pyramid, the lower resolution base image from the adjacent level of the pyramid is upsampled and subtracted from the base image at the given level of the pyramid. This difference image is called a residual image. A fully decomposed image consists of a set of base images and corresponding residual images. The advantage of this representation of the image is that small support region image processing operations can be applied to each of the base and/or residual images so as to produce the same results as using a very large support region operation at the original image resolution. In the case of noise reduction, this permits the use of, for example, 3×3 square regions at each level of the pyramid to effectively noise reduce larger and larger clumps of noise. Once the individual images of the pyramid have been processed, the image decomposition process is essentially run in reverse order to reconstitute the full resolution image.
There are many examples of related prior art in this field. U.S. Pat. No. 5,488,374 (Frankot, et al.) discloses a pyramid decomposition-based noise reduction method that uses simple linear noise filters tuned for each pyramid level. U.S. Pat. No. 5,526,446 (Adelson, et al.) teaches using steerable noise filters within a pyramid decomposition-based architecture. U.S. Pat. No. 5,729,631 (Wober, et al.) reveals using Wiener filters and discrete cosine transforms to noise reduce in the spatial frequency domain within the framework of a pyramid decomposition. U.S. Pat. No. 5,963,676 (Wu, et al.) describes using wavelet decomposition to accomplish its pyramid decomposition and then using an edge-preserving smoothing filter to perform noise reduction at each pyramid level. U.S. Patent Application Publication No. 2002/0118887 (Gindele) discloses a pyramid decomposition-based noise reduction method that uses modified sigma filters tuned for each pyramid level.
A significant problem with existing noise reduction methods is that they are still very computationally intensive when either the image to be noise reduced is very large (e.g. 14 million pixels) or the noise signal is very large with respect to the genuine image signal. When the image consists of a large number of pixels, the required computing resources scales directly with the number of pixels to noise reduce. Using a pyramid decomposition architecture addresses this liability to some extent. When the amount of noise present is large, then generally more complex noise reduction algorithms, such as median filters, must be imbedded into the pyramid architecture to avoid seriously degrading genuine image information. A double jeopardy situation can exist when both circumstances are present.
What is needed is a method that provides the noise reduction capability of a pyramid decomposition approach without relying on complex noise reduction operations at each level of the pyramid so as to keep the required computational intensity to a minimum. This method must still noise reduce in an effective manner when dealing with images with high levels of noise.

Noise reduction in color digital images using pyramid decomposition


A ballistic shield containment system for preventing fragments expelled from an engine assembly from penetrating the casing of an adjacently disposed engine is provided. In a turboprop engine assembly having two power sections connected through a combining gearbox to a single propeller shaft, it is imperative that failure of the rotor disks in one engine not cause failure of the remaining engine. A substantially rectangular shaped panel member is supported at approximately the mid-point between the power sections by a support truss system extending from the panel to a space frame. The space frame is supported by a separate truss system connected to fixed bulkhead. The panel includes reinforcing ribs to prevent fragment penetration and excessive deformation. Each of the truss members is attached at either end to a spherical bearing capable of transmitting force loads while preventing transmission of moment loads.

The present invention generally relates to a propulsion system wherein two high speed turboshaft engines are disposed side-by-side and employed to drive a single output shaft and, more particularly, to a ballistic shield containment system positioned between the engines to prevent rotor burst in one of the engines from adversely impacting the other turboshaft engine.
The principal drawback of a single engine aircraft resides in the almost inevitable result that engine failure will cause the aircraft to crash. For this reason, federal law has long prohibited the carrying of passengers for hire in single engine, propeller-driven fixed wing aircraft. Rather, commercial aircraft that carries passengers must utilize at least two separate engines, allowing one engine to continue to propel the aircraft even if the other engine should fail.
While multiple engines add a considerable and necessary level of safety to operation of the aircraft, they also significantly add to the cost of the aircraft. For small airlines, the expense of the aircraft including the expense of the separate engine assemblies can be the primary factor as to whether the airline can be commercially successful.
In an effort to provide an economical alternative to the need for aircraft employing completely separate engine assemblies, the concept has been put forth of employing dual aircraft engine power sections to drive a single propeller shaft through connections of the engine output shafts to a common gearbox. If one of the engine assemblies should fail, the remaining engine assembly will provide sufficient propulsion. Such a multi-engine, single propeller propulsion system is shown in Soloy, U.S. Pat. No. 4,829,850. The engines drive a single propeller and are separated by a firewall. There is no suggestion in Soloy of utilizing a containment system designed to withstand the serious type of engine failure referred to, by those skilled in the art, as rotor burst. Nor is there any teaching of a detailed attachment/suspension system capable of transmitting forces impacting against the firewall without transmitting any moment loads.
In rotor burst, the compressor or turbine disk breaks apart into portions, which may be as large as a third the size of the disk. These portions typically travel at speeds of up to 450 miles per hour and can easily breach conventional gas turbine engine firewalls. For example, the kinetic energy associated with a rotor burst of a first stage compressor impeller where the fragment is about ⅓ the size of the disk is on the order of 859,040 in-lbf. In comparison, a blade fragment from a first stage compressor impeller has a kinetic energy of about 28,719 in-lbf. For a second turbine stage, the burst fragment may have kinetic energy of about 406,770 in-lbf while the blade fragment 16,973 in-lbf. It is evident that the damage created by rotor burst has the potential for causing extreme damage and even complete failure to an adjacently disposed engine assembly regardless of the presence of a conventional firewall as taught in Soloy.
Because of the danger of fragments from one engine section damaging the remaining engine section, certification for the multi-engine, single propeller shaft design basically requires demonstration that failure of one engine section will not create a hazard to the remaining engine section.
As can be seen, in order to certify a two engine section assembly for commercial passenger use, there is a need for ballistic shield containment system that ensures continuous power is available from one of the two power sections in the event of an uncontained rotor failure in the other power section. Such a containment system must be able to withstand the impact of fragments generated by all types of engine failure up to, and including, rotor burst.
In one aspect of the present invention, a ballistic shield is formed as a substantially rectangular panel member having a uniform thickness of approximately xc2xd inch and preferably formed of metallic material possessing an optimal combination of strength and ductility and low weight density, for example titanium alloy Ti-6-4. The shield has a number of features which combine to resist fragment penetration and excessive deformation and displacement, on the order of 2-3 inches total deformation and displacement relative to the unaffected power section, caused by any type of structural failure including rotor blast. The features include a reinforcing lip mounted on the periphery of the shield which extends outwardly beyond each face of the panel member. In addition, reinforcing ribs are strategically located to extend outwardly from each face of the shield to reinforce specific panel areas where fragments may have the greatest force of impact. The ballistic shield extends in a generally vertical direction approximately equal distance between the two power sections on the same plane as the propeller shaft.
The ballistic shield is supported by a support truss system, which is attached to a multi-part space frame assembly. The space frame, in turn, is connected by a separate space truss system to fixed support assembly such as an aircraft""s forward bulkhead structure. All primary support joints between the ballistic shield and its supporting truss system incorporate spherical bearings to assure that while direct force loads are transmitted through the joints, there will be no transmission of moment loads. Secondary support joints of the ballistic shield are bolted directly to its supporting structure to provide a degree of dynamic frictional damping.
In another aspect of the invention, a turboprop engine assembly including multiple engine power sections driving a single propeller shaft is protected and supported by a multi-part space frame assembly. A ballistic shield is supported by the space frame at a location approximately mid-point between the engine power sections in the same plane as the single propeller shaft. A truss system connects the ballistic shield to the space frame and a separate truss system connects the space frame to the aircraft""s forward bulkhead.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.

Ballistic shield for dual engine single output shaft propulsion system


The present invention provides for various embodiments of a tray energy absorber comprising a base, a first transverse wall that is arcuate and extends from the base, a second transverse wall spaced apart from the first transverse wall and which extends from the base. The tray energy absorber further comprises a plurality of ribs that extend from the base joining the first transverse wall to the second transverse wall. In one embodiment the density of the ribs varies along the transverse width of the tray energy absorber. In another embodiment at least one of the plurality of ribs is greater than 50% of the height of the first transverse wall or the second transverse wall where the rib joins the first and second transverse walls. The present invention also provides for a bumper system used in a vehicle that includes a tray energy absorber attached to a bumper beam. The bumper system optionally includes a fascia that substantially envelops the bumper beam and the tray energy absorber.

Bumper systems typically extend widthwise, or transverse, across the front and rear of a vehicle and are mounted to rails that extend in a lengthwise direction. Many bumper assemblies for an automotive vehicle include a beam and an injection molded energy absorber secured to the beam. Assembly can further include a fascia for covering the beam and the energy absorber. The bumper assembly can further include a separately fabricated under tray, or spoiler, to prevent drag and under current beneath the car body. The under tray can also prevent debris from entering the under hood area.
Desirable energy absorbing bumper systems achieve high efficiency by building load quickly to just under the load limit of the rails and maintain that load constant until the impact energy has been dissipated. Currently, many vehicles, for example automotive vehicles, are designed with an upper and a lower energy absorber that are made to connect to the upper and lower beams, respectively. Upper and lower energy absorbers and bumper beams are commonly designed separately so that the lower energy absorber meets pedestrian impact and some vehicle safety requirements. The new legislation requires a level of pedestrian protection during impact with the front end of an automotive vehicle. The impact energy levels during such an occurrence are much lower than the traditional 5 mph vehicle bumper impacts. Legislation requirements include US FMVSS 5 miles per hour (mph) impact requirements, European ECE42 legislation, Allianz impact requirements and European and Asian Pedestrian Protection for lower and upper legs.
Traditional vehicle bumper systems and energy absorbers are designed to protect vehicle structures and/or occupants of the vehicle during low speed, about 5 miles per hour (mph), in a vehicle-to-vehicle or vehicle-to-solid structure impact. However, conventional bumper systems and energy absorbers are often too stiff to mitigate pedestrian injury, and/or are otherwise, highly complex having a large number of parts which can make them difficult and expensive to manufacture.


It is described at least a method for performing vehicle operation analysis of a driver, comprising retrieving data related to the operation of the vehicle via a mobile device, wherein the mobile device is placed inside the vehicle and the retrieved data is data that is at least provided by data providing units included in the mobile device; adding a driver-specific identifier to the retrieved data which identifies the driver of the vehicle irrespective of the vehicle that is used; performing analysis of the retrieved data in the mobile device, and/or sending the retrieved data to a remote computer and performing analysis of said data in the remote computer, wherein the analysis includes extracting driver-specific vehicle operation schemes and/or calculating a driver-specific safety factor.

The subject-matter described relates to a method for performing vehicle operation analysis of a driver, a computer program product configured to carry out said method and a mobile device configured to carry out said method. Further, the subject-matter described relates to a computer program product being an application to be installed in a vehicle operating system to carry out said above method and to a vehicle with said computer program product being installed in the vehicle operating system.
Computerized analysis of vehicle operation of a driver (driving behavior analysis) can bring about technical advantages: For example, a driving license may be made valid for different countries or companies based on the data obtained from the computerized vehicle operation analysis of a driver who may be applying for a new driving license or the like. Having the information about the driving behavior of said driver at hand it can be enabled, for example, that the driver does not have to undergo additional tests to obtain driving licenses for different countries or companies. Further, the data obtained from the vehicle operation/driving behavior analysis may be used for calculating insurance premiums and the like. An automated and tailor-made calculation of premiums for a specific driver and the personal driving style would be enabled.
Computerized vehicle operation or driving behavior analysis is, for example, described by US 2013/0151288 A1 which, however, i.a. has the technical disadvantage that a mobile device is related to a specific vehicle so that the driver cannot be analyzed if he uses different vehicles, for example in a car-sharing scenario, when he owns several cars or when he is a professional driver using a different company-owned car every day or the like.