32 research outputs found
Adapting Text-based Dialogue State Tracker for Spoken Dialogues
Although there have been remarkable advances in dialogue systems through the
dialogue systems technology competition (DSTC), it remains one of the key
challenges to building a robust task-oriented dialogue system with a speech
interface. Most of the progress has been made for text-based dialogue systems
since there are abundant datasets with written corpora while those with spoken
dialogues are very scarce. However, as can be seen from voice assistant systems
such as Siri and Alexa, it is of practical importance to transfer the success
to spoken dialogues. In this paper, we describe our engineering effort in
building a highly successful model that participated in the speech-aware
dialogue systems technology challenge track in DSTC11. Our model consists of
three major modules: (1) automatic speech recognition error correction to
bridge the gap between the spoken and the text utterances, (2) text-based
dialogue system (D3ST) for estimating the slots and values using slot
descriptions, and (3) post-processing for recovering the error of the estimated
slot value. Our experiments show that it is important to use an explicit
automatic speech recognition error correction module, post-processing, and data
augmentation to adapt a text-based dialogue state tracker for spoken dialogue
corpora.Comment: 8 pages, 5 figures, Accepted at the DSTC 11 Workshop to be located at
SIGDIAL 202
New particle formation events observed at the King Sejong Station, Antarctic Peninsula - Part 2: Link with the oceanic biological activities
Abstract. Marine biota is an important source of atmospheric
aerosol particles in the remote marine atmosphere. However, the relationship between new particle formation and marine biota is poorly quantified.
Long-term observations (from 2009 to 2016) of the physical properties of
atmospheric aerosol particles measured at the Antarctic Peninsula (King
Sejong Station; 62.2∘ S, 58.8∘ W) and satellite-derived
estimates of the biological characteristics were analyzed to identify the
link between new particle formation and marine biota. New particle formation
events in the Antarctic atmosphere showed distinct seasonal variations, with the highest values occurring when the air mass originated from the ocean
domain during the productive austral summer (December, January and February).
Interestingly, new particle formation events were more frequent in the air
masses that originated from the Bellingshausen Sea than in those that
originated from the Weddell Sea. The monthly mean number concentration of
nanoparticles (2.5–10 nm in diameter) was >2-fold higher when the air
masses passed over the Bellingshausen Sea than the Weddell Sea, whereas the
biomass of phytoplankton in the Weddell Sea was more than ∼70 %
higher than that of the Bellingshausen Sea during the austral summer
period. Dimethyl sulfide (DMS) is of marine origin and its oxidative
products are known to be one of the major components in the formation of new
particles. Both satellite-derived estimates of the biological
characteristics (dimethylsulfoniopropionate, DMSP; precursor of DMS) and
phytoplankton taxonomic composition and in situ methanesulfonic acid (84
daily measurements during the summer period in 2013 and 2014) analysis
revealed that DMS(P)-rich phytoplankton were more dominant in the
Bellingshausen Sea than in the Weddell Sea. Furthermore, the number
concentration of nanoparticles was positively correlated with the biomass of
phytoplankton during the period when DMS(P)-rich phytoplankton predominate.
These results indicate that oceanic DMS emissions could play a key role in
the formation of new particles; moreover, the taxonomic composition of
phytoplankton could affect the formation of new particles in the Antarctic
Ocean
Cardiovascular Diseases after Kidney Transplantation in Korea
Cardiovascular disease (CVD) is the leading cause of death in renal allograft recipients with functioning graft. Our study aimed to determine the incidence and the risk factors of cardiovascular disease after renal transplantation in Korea. We retrospectively analyzed 430 adult recipients who underwent kidney transplantation between January 1997 and February 2007. CVD was defined as a composite outcome of ischemic heart disease, cerebrovascular accident and peripheral vascular disease. Mean age of recipients was 40.0±11.8 yr. Mean duration of follow-up was 72±39 months. The cumulative incidence of CVD after renal transplantation was 2.4% at 5 yr, 5.4% at 10 yr and 11.4% at 12 yr. Multivariate analysis revealed that recipient's age, diabetes mellitus and duration of dialysis before transplantation were associated with post-transplant CVD (hazard ratio 1.843 [95% CI, 1.005-3.381], 3.846 [95% CI, 1.025-14.432] and 3.394 [95% CI, 1.728-6.665] respectively). In conclusion, old age, duration of dialysis and diabetes mellitus are important risk factors for post-transplant CVD, although the incidence of post-renal transplant CVD is lower in Korea than that in western countries
Association of Angiotensin II Type 2 Receptor Gene A1818T Polymorphism with Progression of Immunoglobulin A Nephropathy in Korean Patients
We determined the relationship between the progression of immunoglobulin A nephropathy (IgAN) and the A1818T polymorphism in intron 2 of Angiotensin II type 2 receptor (AT2R) gene, which might play protective roles in the pathogenesis of IgAN. Patients with biopsy-proven IgAN were recruited from the registry of the Progressive REnal disease and Medical Informatics and gEnomics Research (PREMIER) which was sponsored by the Korean Society of Nephrology. A1818T polymorphism of AT2R gene was analyzed with PCR-RFLP method and the association with the progression of IgAN, which was defined as over 50% increase in baseline serum creatinine level, was analyzed with survival analysis. Among the 480 patients followed for more than 10 months, the group without T allele had significantly higher rates of progression of IgAN than the group with T allele (11.4% vs. 3.9%, p=0.024), although there were no significant differences in the baseline variables such as initial serum creatinine level, the degree of proteinuria, and blood pressure. In the Cox's proportional hazard model, the hazard ratio of disease progression in the patients with T allele was 0.221 (95% confidence interval for Exp(B): 0.052-0.940, p=0.041) compared to that of without T allele. In conclusion, A1818T polymorphism of AT2R gene was associated with the progression of IgAN
In situ induction of dendritic cell–based T cell tolerance in humanized mice and nonhuman primates
Administration of an ICAM-1–specific antibody arrests dendritic cells in a semi-immature state and facilitates antigen-specific T cell tolerance to islet allografts in humanized mice and Rhesus monkeys
Removal of Particulate Matter by a Non-Powered Brush Filter Using Electrostatic Forces
In urban areas, a major source of harmful particulate matter is generated by vehicles. In particular, bus stops, where people often stay for public transportation, generate high concentrations of particulate matter compared to the general atmosphere. In this study, a non-powered type brush filter that generates electrostatic force without using a separate power source was developed to manage the concentration of particulate matter exposed at bus stops, and the removal performance of particulate matter was evaluated. The dust collection performance of the non-motorized brush filter varied by material, with particle removal efficiencies of 82.1 ± 3.4, 76.1 ± 4.7, and 73.7 ± 4.5% for horse hair, nylon, and stainless steel, respectively. In conditions without the fan running to see the effect of airflow, the particle removal efficiency was relatively low at 58.2 ± 8.4, 53.6 ± 9.2, and 58.0 ± 7.3%. Then, to check the dust collection performance according to the density, the number of brushes was increased to densify the density, and the horse hair, nylon, and stainless steel brush filters showed a maximum dust collection performance of 89.6 ± 2.2, 88.3 ± 3.2, and 82.1 ± 3.8%, respectively. To determine the replacement cycle of the non-powered brush filter, the particulate removal performance was initially 88.0 ± 3.2% when five horse hair brushes were used. Over time, particulate matter tended to gradually decrease, but after a period of time, particulate matter tended to increase again. The purpose of this study is to evaluate the particulate matter removal performance using a brush filter that generates electrostatic force without a separate power source. This study’s brush filter is expected to solve the maintenance problems caused by the purchase and frequent replacement of expensive HEPA filters that occur with existing abatement devices, and the ozone problems caused by abatement devices that use high voltages