Timeliness evaluation of task-oriented networked space-based information system

Task-oriented networked information system is an integrated information system which builds on multi-satellite networking to accomplish one or more tasks. In the background of emer- gency relief for applications, system working flow and response process are analyzed, and a timeliness effectiveness evaluation index system is constructed at multi-task level. The effectiveness is a measurement of promptness of information return. In evalua- tion process, system performance and tasks are associated, then an evaluation model based on efficacy function is established, and different evaluation criteria are selected for different tasks. A distributed simulation system is constructed, and the execution of task is decomposed. The simulation platform provides a comprehensive data source for evaluation. The results are easy to compare with each other, which reflects system time efficiency in different satellites networks and provides actual systems with basis and reference for design and application.

A Study on The Timeliness of Credit Rating on Bond Defaults--Evidence from Chinese Bond Market

With the increase of China’s bond issuance and slowdown of the economic growth,the potential credit risks such as bond default in the bond market are gradually emerging.The frequent occurrence of bond defaults and the problem of false credit ratings make bond investors and market participants more cautious about the credit ratings issued by rating agencies.Based on the default bonds from 2016 to 2019,this paper analyzes the adjustment of rating of defaulted bonds by rating agencies before default.It also compares the impact of both the regulatory events and the entrance of international agencies on timeless of credit ratings on default bonds.At the same time,the divergence of rating timeliness between different rating agencies is compared.The research shows that after the unified supervision of regulators and the punishment of Dagong Global Credit Rating Co.Ltd in 2018,the timeliness of rating agencies'downgrading of defaulted bonds has increased significantly;Compared with other rating agencies,the timeliness of rating agencies owned by international rating agencies are better.

Associated Factors to Immunization Timeliness and Completion in Preterm and Low Birth Weight Infants at Essos Hospital Center Yaounde

Introduction: Vaccination is very often delayed in premature and low birth weight infants. However, timely vaccination is even more important in this population because of their increased susceptibility to infection. Objective: To assess immunization practice and factors associated with vaccine promptness and completeness in former preterm and low-birth-weight infants. Methods: We conducted a retrospective analytical cross-sectional study (January 2017 to February 2019). Main Measurement: Promptness and completeness at each contact, Statistical analysis was performed using R software version 3.6.2, logistic regression was used to estimate the Odds Ratio (OR) and their 95% Confidence Interval (CI). Results: We recruited 310 children aged 12 to 36 months born before 37 weeks with low birth weight, 163 (52.6%) of whom were female. Two hundred and fifty-three had received the vaccines at the indicated age, with promptness rate of 81.6%, and 97.7% had completed routine immunization at 9 months. The mean age at vaccination initiation was 6 days ± 11 and the mean weight at vaccination initiation was 2233 g ± 494. High prematurity and very low birth weight were associated with a high rate of vaccine delay: 61.5% [OR: 15.56;(CI: 3.22 - 118.52;p = 0.002)] and 66.7% [OR: 19.19;(CI: 4.67 - 92.52;p < 0.001)] respectively. Distance > 5 km with EHC [OR: 3.48;(CI: 1.68 - 7.47;p = 0.001)] was associated with poor vaccination. Women in common-law unions had the lowest vaccine readiness rate (60.6%), (OR: 3.36;CI: 1.006 - 10.70;p = 0.038). The frequency of occurrence of post immunization adverse events was 24.5%, with fever type in 94.7%. Conclusion: Almost all premature and/or low-birth-weight children hospitalized at Essos Hospital Center had completed routine immunization at 9 months, and the majority had received the vaccines in a timely manner. Similar study is needed in rural area.

Completeness and Timeliness of Hepatitis B Vaccination in Preschool Children: Determinants for Good and Timely Uptake in Libreville, Gabon

Background: Gabon is endemic for hepatitis B, but they have still not reached the WHO goal for Hepatitis B vaccination coverage. We aimed to determine the rate of completeness and timeliness of hepatitis B vaccination among children under 15 years of age in Libreville. Methods: Cross-sectional study conducted over 9 months, including children randomly selected from vaccination centres, nurseries and kindergartens. We collected data on the child, socio-economic characteristics of the families, and dates of administration of hepatitis B vaccines. We determined the compliance of the vaccination dates according to the vaccination start pattern. Results: We included 453 children, of whom 236 were girls, for a sex ratio of 0.92. A total of 87% (95% CI [83.9% - 90.1%]) of children had started and completed their 3 doses of vaccine before the 12th month of age. 149 subjects had received their 3 doses on time according to the original vaccination schedule, i.e. 32.9% (95% CI [28.6% - 37.2%]). Factors significantly associated with completeness were vaccination in a public centre OR = 114 [47.2 - 347] p st dose OR = 3 [1.6 - 5.5] p < 0.001. Age at first dose was the predictor of timeliness aOR = 1.3 (95% CI [1.2 - 1.5] p 0.001). Conclusion: The respect for the vaccination deadlines is insufficient in our context, solutions exist to improve this situation.

Effect of Corporate Governance Compositions on Financial Reporting Timeliness in Nigerian Deposit Money Banks

This study ascertained the effect of corporate governance compositions on timeliness of financial reporting in deposit money banks in Nigeria.Ex Post Facto research design was employed for this study.Purposive sampling was used to select eight(8)deposit money banks in Nigeria with international authorization.Data were extracted from annual reports and accounts of the sampled banks and analyzed with regression analysis.The results show that board size has a positive and significant effect on financial reporting timeliness deposit money banks in Nigeria,while audit committee independence has a positive but insignificant effect on financial reporting timeliness of deposit money banks in Nigeria.Therefore,on the basis of the findings and conclusions of the study,the study recommends among other things that the number of banks board of directors should play a vital role in how well it can oversee daily operations of the institution and monitor management.

气象观测场在汽车试验场中的应用研究

汽车试验场作为汽车开展道路测试的重要场所,用于验证汽车产品的品质以及可靠性。除了场地道路外,气象条件作为汽车道路测试的重要一环,在《GB/T12534-1990汽车道路试验方法通则》中也有明确要求,如:试验时应是无雨无雾天气,相对湿度小于95%,气温0-40℃,风速不大于3m/s。同时气象条件也作为试验场道路管控的重要依据,实时风速、雨量、能见度等信息为场地管理者发布限速、限行、封场等通知提供必要参考依据,直接影响道路测试安全管控的及时性。因此,文章从气象观测场的建设、气象服务、异常天气道路管控等方面开展气象观测场在汽车试验场中的应用研究。

Influence law of multipoint vibration load on slope stability in Xiaolongtan open pit mine in Yunnan,China

The purpose of this work was to explore the influence law of vibration load on rock mass structure and slope stability.Based on the type and transmission way of vibration stress wave,the main stress in the horizontal and vertical directions was analyzed and the superposition effect of the stress wave was revealed.After the mechanical analysis of the sliding mass,the calculation formulas of the anti-sliding force and the sliding force were derived and the damage mechanism of blasting vibration to the structural plane was defined.In addition,according to the structure and lithologic parameter of the slope as well as the vibration monitoring data,the west slope stability of Xiaolongtan open pit mine was analyzed.The results show that the time-dependent stability factor is proportional to the vibration speed and the peak values appear at the same time.Vibration load promotes the breakage of the structural plane leading to the drop of the west slope stability factor by 0.23%.Under the multipoint simultaneous blasting,the fluctuating laws of the stability factors are consistent.The more the start-up points are,the higher the weakening degree to the slope stability is.Under the multipoint allochronic blasting,the stability factor depends on the synthetic waveform structure of all vibration waves.The greater the blasting time difference is,the lower the weakening degree to the slope stability is.Selecting the reasonable quantity of start-up points and time difference could fully reduce the adverse influence of vibration load to slope stability.

Detection of early-stage research fronts——An example of complex networks research

Purpose:This study aims to detect research fronts of a scientific field in its early development stage using bibliometric indicators developed based on the features of research fronts.Design/methodology/approach:We first focused on conceptualization of'research fronts'and outlined 4 indicators to measure different aspects of the concept:Innovation,timeliness,stability and interdisciplinarity.Then research specialties obtained based on direct citation networks were evaluated with the 4 indicators and research fronts were identified.Finally,methodology was illustrated and verified in the research domain of complex networks.Findings:The results indicate that the proposed method is useful in detecting research fronts in a specific field which is at an early development stage.Research limitations:The quality of clustering results was not assessed.It needs to be further studied whether the method can be applicable to the fields that evolve slowly such as mathematics or are highly specialized like entomology and zoology.Practical implications:This study helps researchers keep abreast of emerging trends and policy-makers formulate science and technology policies and strategic plans.Originality/value:This research provides insights into a quantitative assessment method to detect research fronts of a scientific field in its early development stage.

Multi-objective route planning approach for timely searching tasks of a supervised robot

To performance efficient searching for an operator-supervised mobile robot, a multiple objectives route planning approach is proposed considering timeliness and path cost. An improved fitness function for route planning is proposed based on the multi-objective genetic algorithm （MOGA） for multiple objectives traveling salesman problem （MOTSP）. Then, the path between two route nodes is generated based on the heuristic path planning method A ＊. A simplified timeliness function for route nodes is proposed to represent the timeliness of each node. Based on the proposed timeliness function, experiments are conducted using the proposed two-stage planning method. The experimental results show that the proposed MOGA with improved fitness function can perform the searching function well when the timeliness of the searching task needs to be taken into consideration.

Strengthening District Health Teams Capacity in Surveillance Systems and Response to Public Health Threats in Western Uganda through Field Epidemiology Training Program (FETP)

Aim: To strengthen the District Capacity in surveillance for effective detection, Reporting and Response to Public Health threats. Background: The overall aim of a good surveillance system is to strengthen the capacity of a Health system through training of health personnel who can conduct effective surveillance activities. A good surveillance system is achieved through improved use of complete and timely health information to detect changes in time to institute a rapid response to the suspected outbreak of Public Health events. This assessment followed a 3-month Field Epidemiology Training program undertaken by the investigator who applied the acquired knowledge and skills in completion of the assessment. Study Design: It was a descriptive cross-sectional, institutional based epidemiological investigation conducted at district level and Health Centre 1V in Kabarole from 15th December 2019-March 2020. eReports were retrieved from DHIS-2 for epidemiological weeks 44 in 2019 to week 3 in 2020. Data analysis: Micro soft word excel program was used to determine the reporting rates, epidemic disease trends and construction of malaria channel. SWOT analysis was done to identify poor HMIS reporting as the lead surveillance quality challenge and route cause analysis done to determine underlying causes. Results: Weekly reports analyzed were from a total of 53 Health facilities and one Health Centre four for malaria channel construction. Of the 53 functional Health facilities assessed in the district, the average reporting Timeliness was 32% and Completeness at 63% from week 44 in 2019 to week 3 in 2020. This finding shows that the district was not achieving the 80% Timeliness and 80% Completeness national target. The poor reporting situation implies that the district may not detect an emerging Public Health Event and respond in time. Poor reporting rate was linked to knowledge gap among reporting staff in completion of the newly revised HMIS tools and lack of support supervision. The analyzed data revealed that the district had increased dysentery, measles and typhoid fever cases. The dysentery and typhoid fever cases had reached and surpassed the Alert and Action thresh hold levels however there was no reported death from these diseases. Further inquiry revealed that Typhoid fever was being diagnosed using WIDAL test as opposed to WHO recommendation of stool or blood culture. The noted typhoid fever outbreak in the district was therefore being based on wrong laboratory tests hence regarded by the researcher as speculative. Findings on malaria channel revealed a normal and expected trend of malaria in Kabarole district in 2020. Conclusion: knowledge and skills from FETP-training enabled the investigator to establish the fact that the district’s surveillance system was less sensitive in detecting Public Health events for a quick response. Intensified targeted support supervision and mentorships of all health workers on reporting could help improve the districts surveillance system.

Timing of Adjuvant Chemotherapy and Survival in Patients with Stage II/III Rectal Cancer

Background: Treatment guidelines in the 1990s established surgery followed by chemoradiotherapy as the standard treatment for stage II/III rectal cancer. Our aim was to investigate the association between the timing of adjuvant treatment and patient survival in practice and identify demographic/clinical factors associated with treatment patterns. Methods: All residents of Alberta diagnosed with stage II/III rectal adenocarcinoma in 2000-2005 who had surgery were included in the study. Demographic and clinical data were obtained from the Alberta Cancer Registry and linked to hospital data and socioeconomic data from the 2001 Canadian Census. Overall and cancer-specific hazard ratios of death were estimated using Cox proportional hazards models. Results: 1243 patients were included in the study;636 (51%) patients received treatment consistent with guidelines. Patients who received adjuvant chemotherapy 12 - 16 weeks after surgery or more than 16 weeks/ did not receive it had a 43% and 58% higher risk of rectal cancer death, respectively, compared to those who received it within 8 weeks of surgery. Conclusion: Adjuvant chemotherapy for stage II/III rectal cancer should be initiated within 12 weeks after surgery to maximize treatment benefits. Efforts to increase the proportion of patients treated within 12 weeks after surgery are needed.

A combined method for high-speed rail seismic monitoring and early warning

The ground motion characteristics include the strength, frequency spectrum and duration time. In China, the PGA （peak ground acceleration） is commonly used in determination of whether an earthquake warning is necessary when the high-speed train is on the rail. This method has not given an earthquake early warning time, and it only considers the strength factor of an earthquake, so the system may release an alarm for the near and small earthquakes which are no destructive. The new alarm method reconciles the timeliness and stability. It issues a P wave warning when the system receives seismic wave first, which will make the train to decelerate. Then, the system will confirm whether the P wave alarm is correct using the joint alarm result of CAV （cumulative absolute velocity） and PGA, and then take measures according to the result. The new method eliminates the interference from the near and small earthquakes, as well as the large and far earthquakes, and ensures the safety of the train when it is subjected to earthquakes. In this paper, we use seismic data to simulate the combined alarm of CAV and PGA, and then obtain the cumulative time of CAV and the time interval between CAV and PGA. Finally, we compare the new method with the double-station, earthquake monitoring alarm method which is currently used on China＇s high-speed rail. and find the new alarm method is better in the aspect of alarm timeliness.

Measuring the Impact of DoS Attack on Availability: Empirical Study Based on Accessibility

Information Security is determined by three well know security parameters i.e. Confidentiality, Integrity and Availability. Availability is an important pillar when it comes to security of an information system. It is dependent upon the reliability, timeliness and accessibility of the Information System. This paper presents an analytical view of the fact that when Accessibility is degraded during the presence of an ongoing attack, the other factors reliability and timeliness can also get affected, therefore creating a degrading impact on the overall Availability of the system, which eventually leads to the Denial of Service Attack and therefore affecting the security of the System.

Local Hybrid Linear State Estimation for Electric Power Systems Using Stream Processing

The increasing penetration of renewable energy resources with highly fluctuating outputs has placed increasing concern on the accuracy and timeliness of electric power system state estimation(SE).Meanwhile,we note that only a fraction of system states fluctuate at the millisecond level and require to be updated.As such,refreshing only those states with significant variation would enhance the computational efficiency of SE and make fast-continuous update of states possible.However,this is difficult to achieve with conventional SE methods,which generally refresh states of the entire system every 4–5 s.In this context,we propose a local hybrid linear SE framework using stream processing,in which synchronized measurements received from phasor measurement units(PMUs),and trigger/timingmode measurements received from remote terminal units(RTUs)are used to update the associated local states.Moreover,the measurement update process efficiency and timeliness are enhanced by proposing a trigger measurement-based fast dynamic partitioning algorithm for determining the areas of the system with states requiring recalculation.In particular,non-iterative hybrid linear formulations with both RTUs and PMUs are employed to solve the local SE problem.The timeliness,accuracy,and computational efficiency of the proposed method are demonstrated by extensive simulations based on IEEE 118-,300-,and 2383-bus systems.

Multi-level determinants of failure to receive timely and complete measles vaccinations in Southwest China:a mixed methods study

Background Measles outbreaks re-emerged in 2013–2014 in Guangxi Zhuang Autonomous Region of China,where measles immunisation coverage is high.The discrepancy between the vaccination coverage and outbreaks indicates that timeliness is crucial,yet there is limited knowledge on the health system barriers to timely vaccination.Using integrated evidence at the household,village clinic,and township hospital levels,this study aimed to identify the determinants of failure in receiving timely measles vaccinations among children in rural Guangxi.Methods A multi-stage stratified cluster sampling survey with a nested qualitative study was conducted among children aged 18–54 months in Longan,Zhaoping,Wuxuan,and Longlin counties of Guangxi from June to August 2015.The status of timely vaccinations for the first dose of measles-containing vaccine(MCV1)and the second dose of measles-containing vaccine(MCV2)was verified via vaccination certificates.Data on household-level factors were collected using structured questionnaires,whereas data on village and township-level factors were obtained through in-depth interviews and focus group discussions.Determinants of untimely measles vaccinations were identified using multilevel logistic regression models.Results A total of 1216 target children at the household level,120 villages,and 20 township hospitals were sampled.Children were more likely to have untimely vaccination when their primary guardian had poor vaccination knowledge[MCV1,odds ratio(OR)=1.72;MCV2,OR=1.51],had weak confidence in vaccines(MCV1,OR=1.28–4.58;MCV2,OR=1.42–3.12),had few practices towards vaccination(MCV1,OR=12.5;MCV2,OR=3.70),or had low satisfaction with vaccination service(MCV1,OR=2.04;MCV2,OR=2.08).This trend was also observed in children whose village doctor was not involved in routine vaccination service(MCV1,OR=1.85;MCV2,OR=2.11)or whose township hospital did not provide vaccination notices(MCV1,OR=1.64;MCV2,OR=2.05),vaccination appointment services(MCV1,OR=2.96;MCV2,OR=2.74),sufficient and uniformly distributed sessions for routine vaccination(MCV1,OR=1.28;MCV2,OR=1.17;MCV1,OR=2.08),or vaccination service on local market days(MCV1,OR=2.48).Conclusions Guardians with poor knowledge,weak beliefs,and little practice towards vaccination;non-involvement of village doctors in routine vaccinations;and inconvenient vaccination services in township hospitals may affect timely measles vaccinations among children in rural China.

Fair Non-Repudiation for Web Services Transactions

To safeguard the interests of transacting parties,non-repudiation mechanisms need to assure fairness and timeliness.The non-repudiation service currently implemented usually does not consider the requirement of fairness and the fair non-repudiation protocols to date can not be suitably applied in real environment due to its complex interaction.This paper discusses the transaction-oriented non-repudiation requirement for Web services transaction,analyzes the constraints of the traditional model for the available fair non-repudiation protocols and designs a new Online-TTP fair non-repudiation protocol.The new protocol provides a fair non-repudiation solution to secure Web services transactions and can be embedded into a single Web service call.The protocol adopts evidence chained to decreasing the overhead of evidence verification and management and alleviates the overhead of certificate revocation checking and time-stamp generation for signatures.The protocol has strong fairness,timeliness,efficiency and practicability.

CO-HCCA:Bandwidth Allocation Strategy in Internet of Vehicles with Dynamically Segmented Congestion Control

Hybrid coordination function controlled channel access(HCCA)applied in wireless ad hoc network systems is the strategy to allocate the bandwidth resources of control channel(CCH)and service channels(SCHs).With the continuous development of Internet of vehicles(IoV)technologies,it is difficult for HCCA to support traffic information services,such as low delay along with high-frequency dissemination of security beacons and large capacity interaction of image data.Fusing the fundamental theories of No.7 signaling system and 5G-IoV technologies,this paper proposes a novel channel bandwidth allocation strategy named CO-HCCA,which matches CCH time slot numbers with on board units(OBUs)numbers to reduce the congestion of channel access demand information(CADI);and also illustrates a dynamic segment adjusting algorithm of the time slots.On one hand,in the channel reservation stage of CCH control cycle,OBUs are sorted according to the priority of data transmission,and then the corresponding transmission slots are adopted orderly according to the OBUs numbers,so as to decrease the collision probability of high-frequency dissemination of CADI.On the other hand,for the quickly arriving and leaving OBUs in coverage of roadside base station(RBS),the prediction of bandwidth segments is dynamically adjusted to adapt to the time-varying characteristic of the connected vehicle scenarios.Modeling calculation and objective comparison on OMNeT++computing platform show that the proposed CO-HCCA strategy can effectively reduce the channel congestion of IoV,and in the scenario of high-density data interaction,it is beneficial to promote the transmission timeliness of security beacons and the package delivery rate(PDR)of high bit-rate multiple information.

A numerical and an analytical method for optimum planting date determination

Apart from number and size of machines in a farm,operations scheduling can also affect timeliness costs.In this study a new equation was presented for determination of timeliness costs and it was proven that the new equation is a generalization of the well-known ASABE standard equation.Based on the new equation,a parameter namely,timeliness index was defined that indicates the distribution of an operation around the optimum time of performing the operation.By minimizing the index,the whole timeliness cost is minimized.Since the planting operation is highly sensitive to its time of accomplishment,timeliness cost was determined accordingly.In this study the optimum planting starting date(opls)regarding the concept of timeliness costs,was determined.If for any reason,the planting operation cannot be performed in the minimum planting period,an optimization method is required to determine opls.For this,a numerical approach and an analytical method were presented for determination of opls and a computer model was developed based on the numerical method.opls was determined for the Research Farm of the University of Tehran in Karaj–Iran and both methods showed good agreement with each other.