• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.41 no.5
• /
• pp.19-25
• /
• 2004

In this paper, we propose optimal and suboptimal serial code acquisition schemes for chip-asynchronous direct-sequence spread-spectrum systems. The conventional serial code acquisition scheme is to compare each value of correlator outputs with a threshold individually. However, such a scheme is optimum only under the chip-synchronous assumption which is actually very difficult to be held prior to acquisition at the receiver because the signal-to-noise ratios before despreading are very low. In this paper, an optimal serial code acquisition scheme is derived based on the maximum-likelihood criterion under the more realistic and general chip-asynchronous environments. A suboptimal scheme, which is simpler but yields comparable performance to the optimal one, is also derived based on the criterion of local detection power Numerical results show that, under the chip-asynchronous environments, both the optimal and suboptimal serial code acquisition schemes outperform the conventional serial code acquisition scheme.

• Journal of KIISE:Software and Applications
• /
• v.30 no.1_2
• /
• pp.129-139
• /
• 2003

The PC cluster architecture is considered as a cost-effective alternative to the existing supercomputers for realizing a high-performance information retrieval (IR) system. To implement an efficient IR system on a PC cluster, it is essential to achieve maximum parallelism by having the data appropriately distributed to the local hard disks of the PCs in such a way that the disk I/O and the subsequent computation are distributed as evenly as possible to all the PCs. If the terms in the inverted index file can be classified to closely related clusters, the parallelism can be maximized by distributing them to the PCs in an interleaved manner. One of the goals of this research is the development of methods for automatically clustering the terms based on the likelihood of the terms' co-occurrence in the same query. Also, in this paper, we propose a method for duplicate distribution of inverted index records among the PCs to achieve fault-tolerance as well as dynamic load balancing. Experiments with a large corpus revealed the efficiency and effectiveness of our method.

• Mycobiology
• /
• v.48 no.2
• /
• pp.95-103
• /
• 2020

The genus Termitomyces (Lyophyllaceae, Basidiomycota) is often associated with fungus-feeding termites (Macrotermitinae) due to their strong symbiotic relationships. The genus is widely found exclusively in certain regions of Africa and Asia. They are recognized as edible mushroom within Southeast Asia as well. But it is often misidentified based on morphology by the local communities especially in Malaysia for Chlorophyllum molybdites which is a highly poisonous mushroom. Thus, it is necessary to study the genus for Malaysia with the synergy of using both morphological and molecular identification. In this study, we aim to describe another new species as an addition to the genus Termitomyces found within Sabah, Malaysia. We generated two new sequences (nrLSU and mtSSU) for the new species and a total of 28 nrLSU and mtSSU sequences were retrieved from GenBank for the phylogenetic analysis using maximum likelihood and Bayesian inferences. We identified that the new collection from Sabah province is a new species and named as Termitomyces gilvus based on the termites found in the mound. A phylogeny tree made from the concatenated genes of LSU and mtSSU suggests that T. gilvus is closely related to T. bulborhizus from China. According to our results, the combination of molecular and morphology proved to be a robust approach to re-evaluate the taxonomic status of Termitomyces species in Malaysia. Additional surveys are needed to verify the species diversity and clarify their geographic distribution.

• Communications for Statistical Applications and Methods
• /
• v.15 no.3
• /
• pp.465-481
• /
• 2008

Item response theory(IRT) estimates latent ability of a subject based on the property of item and item parameters using item characteristics curve(ICC) of each item case. The initial value and another problems occurs when we try to estimate item parameters of IRT(e.g. the maximum likelihood estimate). Thus, we propose the asymptotic approximation method(AAM) to solve the above mentioned problems. We notice that the proposed method can be thought as an alternative to estimate item parameters when we have small size of data or need to estimate items with local fluctuations. We developed 'Any Assess' and tested reliability of the system result by simulating a practical use possibility.

• Toxicological Research
• /
• v.33 no.4
• /
• pp.291-297
• /
• 2017

This study was performed to investigate the dose-response relationship between average daily cadmium dose (ADCD) from rice and the occurrence of urinary cadmium (U-Cd) in individuals eating that rice. This was a retrospective cohort designed to compare populations from two areas with different levels of cadmium contamination. Five-hundred and sixty-seven participants aged 18 years or older were interviewed to estimate their rice intake, and were assessed for U-Cd. The sources of consumed rice were sampled for cadmium measurement, from which the ADCD was estimated. Binary logistic regression was used to examine the association between ADCD and U-Cd (cut-off point at $2{\mu}g/g$ creatinine), and a correlation between them was established. The lowest estimate was $ADCD=0.5{\mu}g/kg\;bw/day$ [odds ratio (OR) = 1.71; with a 95% confidence interval (CI) 1.02-2.87]. For comparison, the relationship in the contaminated area is expressed by $ADCD=0.7{\mu}g/kg\;bw/day$, OR = 1.84; [95 % CI, 1.06-3.19], while no relationship was found in the non-contaminated area, meaning that the highest level at which this relationship does not exist is $ADCD=0.6{\mu}g/kg\;bw/day$ [95% CI, 0.99-2.95]. Rice, as a main staple food, is the most likely source of dietary cadmium. Abstaining from or limiting rice consumption, therefore, will increase the likelihood of maintaining U-Cd within the normal range. As the recommended maximum ADCD is not to exceed $0.6{\mu}g/kg\;bw/day$, the consumption of rice grown in cadmium-contaminated areas should not be more than 246.8 g/day. However, the exclusion of many edible plants grown in the contaminated area from the analysis might result in an estimated ADCD that does not reflect the true level of cadmium exposure among local people.

• Fisheries and Aquatic Sciences
• /
• v.27 no.5
• /
• pp.294-305
• /
• 2024

Tomini Bay in Gorontalo offers significant potential for amphidromous goby-fry, a group of fish found in at least five estuaries in the area, namely Bone-Bolango, Paguyaman, Bilungala, Tombulilato, and Taludaa Estuaries. Preliminary results were limited to only two locations in estuarine waters, namely the Bone-Bolango and Paguyaman rivers. Further exploration of goby-fry species in various locations within Tomini Bay is essential to enhance knowledge about the abundance and aid conservation efforts. Therefore, this study identified the goby-fry species and created their distribution map in the waters of Tomini Bay Gorontalo. The samples used were obtained from daily catches of fishermen in the five estuaries during the recruitment period from February to September 2022. These samples were categorized based on their morphological similarities and specific melanophore patterns. Distinct groups with different melanophore patterns from those previously reported were identified as newly recorded species, photographed, and described in terms of their morphology. Furthermore, two specimens from each newly recorded species underwent molecular identification using the cytochrome oxidase subunit 1 (COI) gene for DNA amplification and were analyzed through the Basic Local Alignment Search Tool (BLAST) method. The phylogenetic tree was constructed using the Maximum Likelihood Method. The results showed the existence of nongoby-fry species caught together with goby fry school. A total of 75,881 goby-fry and 1,687 nongoby-fry were successfully collected. Among the goby-fry species, 13 were identified, including three new records, namely Eleotris fusca (Forster, 1801), Sicyopterus microcephalus (Bleeker, 1855), and Sicyopus zosterophorus (Bleeker, 1856). This study also documented the existence of nongoby-fry species, namely Anguilla celebesensis (Kaup, 1856), Moringua microchir (Bleeker, 1853), and Microphis leiaspis (Bleeker, 1854). It significantly contributed to the understanding of fish biodiversity in Tomini Bay.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.19 no.3
• /
• pp.93-101
• /
• 2017

The distribution of inter-annual variation in temperature would help evaluate the likelihood of a climatic risk and assess suitable zones of crops under climate change. In this study, we evaluated two methods to estimate the standard deviation of temperature in the areas where weather information is limited. We calculated the monthly standard deviation of temperature by collecting temperature at 0600 and 1500 local standard time from 10 automated weather stations (AWS). These weather stations were installed in the range of 8 to 1,073m above sea level within a mountainous catchment for 2011-2015. The observed values were compared with estimates, which were calculated using a geospatial correction scheme to derive the site-specific temperature. Those estimates explained 88 and 86% of the temperature variations at 0600 and 1500 LST, respectively. However, it often underestimated the temperatures. In the spring and fall, it tended to had different variance (e.g., increasing or decreasing pattern) from lower to higher elevation with the observed values. A regression analysis was also conducted to quantify the relationship between the standard deviation in temperature and the topography. The regression equation explained a relatively large variation of the monthly standard deviation when lapse-rate corrected temperature, basic topographical variables (e.g., slope, and aspect) and topographical variables related to temperature (e.g., thermal belt, cold air drainage, and brightness index) were used. The coefficient of determination for the regression analysis ranged between 0.46 and 0.98. It was expected that the regression model could account for 70% of the spatial variation of the standard deviation when the monthly standard deviation was predicted by using the minimum-maximum effective range of topographical variables for the area.

• The Plant Pathology Journal
• /
• v.40 no.1
• /
• pp.73-82
• /
• 2024

Gardenia (Gardenia jasminoides) is a popular and economically vital plant known for its ornamental and medicinal properties. Despite its widespread cultivation, there has been no documentation of plant viruses on gardenia yet. In the present study, gardenia leaves exhibiting symptoms of plant viral diseases were sampled and sequenced by both metatranscriptome and small RNA sequencing. As a consequence, bean common mosaic virus (BCMV) was identified in gardenia for the first time and named BCMV-gardenia. The full genome sequence of BCMV-gardenia is 10,054 nucleotides (nt) in length (excluding the poly (A) at the 3' termini), encoding a large polyprotein of 3,222 amino acids. Sequence analysis showed that the N-termini of the polyprotein encoded by BCMV-gardenia is less conserved when compared to other BCMV isolates, whereas the C-termini is the most conserved. Maximum likelihood phylogenetic analysis showed that BCMVgardenia was clustered closely with other BCMV isolates identified outside the leguminous plants. Our results indicated that the majority of BCMV-gardenia virus-derived small interfering RNAs (vsiRNAs) were 21 nt and 22 nt, with 21 nt being more abundant. The first nucleotide at the 5' termini of vsiRNAs derived from BCMV-gardenia preferred U and A. The ratio of vsiRNAs derived from sense (51.1%) and antisense (48.9%) strands is approaching, and the distribution of vsiRNAs along the viral genome is generally even, with some hot spots forming in local regions. Our findings could provide new insights into the diversity, evolution, and host expansion of BCMV and contribute to the prevention and treatment of this virus.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.2
• /
• pp.251-258
• /
• 2017

The objective of this study was to analyze patient satisfaction and perception of nutritional counseling services quality. A patient satisfaction and perception survey was conducted for 1,095 patients from 43 tertiary hospitals and 20 general hospitals. The number of returned questionnaires was 656 (response rate: 60.0%). Data from 633 questionnaires were analyzed after the questionnaires with unanswered items were excluded. Five domains were identified from the result of the factor analysis using the maximum likelihood and oblique rotation. The five domains were named empathy, responsiveness, tangibles, reliability, and skill and specialty. Patient perception mean score of nutritional counseling was 4.54/5.00. Patient satisfaction scores were significantly higher in empathy (P<0.001), responsiveness, and skill and specialty (P<0.01) with a college or graduate school education than in patients with a middle school education. There was no statistically significant difference between satisfaction scores in tertiary hospitals and those in general hospitals, but patients in capital hospitals reported significantly higher scores than their local counterparts in empathy, responsiveness, reliability, skill and specialty (P<0.001), and tangibles (P<0.05). In responsiveness, significantly higher (P<0.01) scores were observed in patients who received nutritional counseling only once compared to patients who received counseling two times. Patients perception of nutritional counseling services was significantly correlated with their satisfaction of five domains, reliability (r=0.721), responsiveness (r=0.697), empathy (r=0.690), skill and specialty (r=0.678), and tangibles (r=0.622).