New Method of Solving the Proper Rational Function and Application to Electrical Control System

Chen Chung-Cheng,Chen Yen-Ting 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.4

The paper is dedicated to develop a new method of addressing the linear nonhomogeneous time-invariant diff erential equation with same diff erential numbers for inputs and outputs. The Laplace transformed output of the electrical state-space equation is a rational function with the same degrees of the numerator and the denominator, and then the bored processes involving the long division of both complicated polynomials, the expanded multiplication of all polynomial factors, the diff erentiation of complicated polynomials and the complex derivations of all partial fraction parameters are inevitable for existing traditional methods. However, by applying the proposed method in this paper, we can explicitly express the general form of the desired output solution and directly solve the desired problem with shorter time than those traditional approaches. To give the signifi cant applications of the new proposed method, we apply it to address the famous electrical circuit based on our recent researches of Chen’s electrical unifying approach.

A Simple Timeout Algorithm for Point-to-Multipoint ABR Service

Lai, Wei-Kuang,Chen, Chien-Ting,Li, Chilin The Korea Institute of Information and Commucation 2004 Journal of communications and networks Vol.6 No.1

The ABR point-to-multipoint connection is now playing a more important role than before. Many consolidation algorithms have been proposed to solve the consolidation noise problem and the slow transient response problem. But few timeout algorithms are proposed to handle the non-responsive branches for the multicast connections. Chen’s algorithm needs exchanging control messages between switches [9]. Besides, it may mistake a responsive branch as a non-responsive branch because of fast changes in source rates, which causes wrong information in BRM cells and may lead to network congestion and data losses in the responsive branch. We propose a simple timeout algorithm which can handle the non-responsive branches without exchanging message between switches. The timeout value for each switch is computed locally. Simulation results show that the proposed timeout algorithm can efficiently handle the non-responsive branches and utilize the available bandwidth within a small period of time. In addition, our algorithm could handle the situation when the source rates change quickly.

Dispersal and Control of Anammox Granular Sludge at High Substrate Concentrations

Ting-Ting Chen,Ping Zheng,Li-Dong Shen,Chong-Jian Tang,Shuang Ding 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.5

This paper reports about the dispersal and control of anammox granular sludge at high substrate concentrations. The results demonstrate that anammox granular sludge would turn into flocculent sludge when the substrate concentrations exceed the inhibitory threshold concentrations, with an apparent drop in the settling velocity of anammox sludge from 73.73 to 16.49 m/h. Moreover, the sludge was washed out of the reactor and a decrease in the nitrogen removal rate from 23.82 to 16.97kg N/(m3/day) was observed. The dominant anammox bacteria in the granular and flocculent sludge were Candidatus Kuenenia stuttgartiensis; however, the contents of heme c and extracellular polymeric substances in the flocculent sludge were much lower than in the granular sludge. Furthermore, the chemical composition of extracellular polymeric substances was different. The high nitrite concentrations more than the inhibitory threshold concentrations were regarded as the reason for the observed granular sludge dispersal and deterioration in reactor performance. The apparent dispersed granular sludge and malfunction of reactor performance could be recovered by means of washing out the residual substrate from the reactor and then re-running the reactor from low substrate concentrations.

Three birds with one stone: Nitrilotriacetic acid interface anchoring helps prepare efficient and stable perovskite solar cells

Chen Ting,Liu Pengfei,Liu Tianxiao,Li Xueyuan,Wang Huihui,He Tingwei,Liu Zhiyong 한국물리학회 2024 Current Applied Physics Vol.58 No.-

Electron transport layer (ETL) plays an important role in perovskite solar cells (PSCs). In this paper, a stable and cheap metal chelating agent, subnitrotriacetic acid (NTA), was used to modify SnO2 ETL in two ways:1) By incorporating NTA into SnO2 colloidal dispersion, the oxygen vacancy causing charge recombination was greatly reduced, and the recombination of psc was reduced by reducing the introduction of surface Ovs, 2) Spin-coating NTA at the SnO2/perovskite interface not only manages a large number of oxygen vacancies generated by high-temperature annealing, but also interacts with the unpaired Pb2+ in the perovskite absorption layer by interface modification of the C=O bond in NTA, passivates the surface of the perovskite layer, inhibits ion migration, stabilize the perovskite structure, and avoid its collapse, while significantly reducing the defect state density. By inhibiting the shallow interface trap and reducing the non-radiative recombination, efficient and stable perovskite solar cells were prepared. Under the condition of relative humidity greater than 40 % (RH), the efficiency of perovskite solar cells prepared by interface-anchored NTA was increased to 22.6 %, and the stability was significantly enhanced.

Experimental investigation on mass flow characteristics of R245fa through electronic expansion valve

Chen, Ting,Cha, Dong An,Kwon, Oh Kyung Elsevier 2017 Applied thermal engineering Vol.125 No.-

<P><B>Abstract</B></P> <P>In this paper, the mass flow rate characteristics of R245fa refrigerant flowing through electronic expansion valves (EEV) under varying operating conditions are studied experimentally. It is found that the mass flow rate increases with increasing EEV opening, condensing temperature, subcooling temperature, and orifice diameter. Based on the measured experimental data, two empirical correlations for mass flow rate prediction of R245fa through EEVs are proposed using the power-law correlation and the polynomial fit correlation. Predicted data of the polynomial fit method showed more consistency with the experimental results compared to that of power-law correlation, and 96.6% of the predicted mass flow rates deviate from the experimental data within ±10%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The mass flow rate characteristics of R245fa through EEVs are studied experimentally. </LI> <LI> Two empirical correlations for mass flow rate prediction are proposed. </LI> <LI> Polynomial fit correlation gives a better agreement with experimental data compared to that of power-law correlation. </LI> <LI> Relative deviations of polynomial fit correlation are within 10%. </LI> </UL> </P>

Enhancing antibacterial activity of geminized cationic amphiphilic polymer via structure control and self-assembly regulation

Ting Chen,Lianyu Zhao,Ziyuan Wang,Jishi Zhao,Yan Li,Hangyu Long,Ming Yang 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.90 No.-

A novel geminized amphiphilic polymer containing double cationic head groups and hydrophobic tails ineach structural unit (denoted as PAGBn), has been prepared in our study. The self-assembly behavior onthe solid/liquid interface was investigated by quartz crystal microbalance with dissipation (QCM-D),steady-statefluorescence, dynamic light scattering (DLS) and transmission electron microscope (TEM). Atwo-regime buildup can be observed, where thefirst regime is attributed to the rapid adsorption ofpolymers, while a rearrangements of pre-adsorbed molecules and their aggregation on the surfacedominate the second regime, exhibiting a formation of aggregates in large sizes due to the effect of thecharge density and hydrophobes on the self-assembly process. It exhibits a drastically enhanced killingefficiency of99.9% against both of Staphylococcus aureus and Escherichia coli bacteria for PAGBncompared with other traditional single-chained polymers, through the reinforced synergistic effect ofelectrostatic and hydrophobic interactions, and the formation of large-sized polymer aggregates,encompassing and killing the bacteria more efficiency. Ourfindings reveal the antibacterial mechanismand the correlation between antibacterial activity and aggregates structure, providing a basis for thedevelopment of super-antibacterial materials in the infection resistant applications.

Empirical correlation development of R245fa flow in electronic expansion valves

Chen, Ting,Bae, Kyung Jin,Kwon, Oh Kyung Elsevier 2018 International Journal of Refrigeration Vol.88 No.-

<P><B>Abstract</B></P> <P>The applications of electronic expansion valves in high temperature heat pump have increased rapidly. However, correlations for predicting R245fa mass flow rate through electronic expansion valves in high temperature heat pump are very limited in open literatures. In this study, mass flow rate characteristics of R245fa refrigerant flowing through electronic expansion valves with different operational conditions are studied experimentally, and empirical correlations are proposed based on the experimental data. The results reveal that the mass flow rate increases with increasing opening degree, condensation temperature, subcooling, and orifice diameter. Based on a modified single phase orifice equation, two empirical correlations are proposed by using the power-law correlation and the polynomial fit correlation, and over 92% of the predicted data deviate from the experimental data within ±15%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The mass flow rate of R245fa through 3 EEVs is investigated experimentally. </LI> <LI> Flow pattern of R245fa through EEVs is discussed. </LI> <LI> Two empirical correlations for mass flow rate prediction are proposed. </LI> <LI> Relative deviations of results of two proposed correlations are almost within 15%. </LI> </UL> </P>

Prediction of Chemotherapeutic Response in Unresectable Non-small-cell Lung Cancer (NSCLC) Patients by 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) Assay

Chen, Juan,Cheng, Guo-Hua,Chen, Li-Pai,Pang, Ting-Yuan,Wang, Xiao-Le Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.5

Background: Selecting chemotherapy regimens guided by chemosensitivity tests can provide individualized therapies for cancer patients. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium, inner salt (MTS) assay is one in vitro assay which has become widely used to evaluate the sensitivity to anticancer agents. The aim of this study was to evaluate the clinical applicability and accuracy of MTS assay for predicting chemotherapeutic response in unresectable NSCLC patients. Methods: Cancer cells were isolated from malignant pleural effusions of patients by density gradient centrifugation, and their sensitivity to eight chemotherapeutic agents was examined by MTS assay and compared with clinical response. Results: A total of 37 patients participated in this study, and MTS assay produced results successfully in 34 patients (91.9%). The sensitivity rates ranged from 8.8% to 88.2%. Twenty-four of 34 patients who received chemotherapy were evaluated for in vitro-in vivo response analysis. The correlation between in vitro chemosensitivity result and in vivo response was highly significant (P=0.003), and the total predictive accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for MTS assay were 87.5%, 94.1%, 71.4%, 88.9%, and 83.3%, respectively. The in vitro sensitivity for CDDP also showed a significant correlation with in vivo response (P=0.018, r=0.522). Conclusion: MTS assay is a preferable in vitro chemosensitivity assay that could be use to predict the response to chemotherapy and select the appropriate chemotherapy regimens for unresectable NSCLC patients, which could greatly improve therapeutic efficacy and reduce unnecessary adverse effects.

Evaluation of secondary cytoreduction surgery in platinum-resistant ovarian cancer patients within three-line recurrent: a multicenter, randomized controlled study

Ting-Ting Chen,Junfen Xu,Bairong Xia,Hui Wang,Yuanming Shen 대한부인종양학회 2024 Journal of Gynecologic Oncology Vol.35 No.1

Background: Epithelial ovarian cancer is the leading cause of death among gynecologicalmalignancies. Platinum resistance remains a dilemma and bottleneck in treatment, andsalvage chemotherapy has limited effectiveness. Recently, the role of secondar y cytoreductivesurger y (SCS) in patients with platinum-resistant recurrent ovarian cancer (ROC) has causedattention especially in patients with oligometastases. However, there is neither high-qualityevidence-based evidence nor standardized criteria for selecting SCS for patients withplatinum-resistant ROC until now. Methods: This multicenter, randomized, controlled clinical trial is to evaluate the valueof SCS and to clarif y reliable criteria of utilizing SCS in women with ROC, which is led byGynecologic Oncology Group, Women’s Hospital, Zhejiang University School of Medicine. Recruitment has started on Januar y 1st, 2023, and is scheduled to end in December 2026. One hundred and forty participants with platinum-resistant ROC who meet the “RSCScriteria” will be randomized assigned at a ratio of 1:1 to either the experimental arm or thestandard arm. Patients in the experimental arm will receive SCS followed by non-platinumsingle agent chemotherapy (paclitaxel, gemcitabine or liposomal adriamycin) for at least4 cycles while patients in the standard arm will be provided with only non-platinum singleagent chemotherapy. The primar y outcome is progression-free sur vival. The secondar youtcomes are overall sur vival, adverse events and health-related cancer-specific quality of life. Trial Registration: ClinicalTrials.gov Identifier: NCT05633199

Experimental Investigation on the Mass Flow Rate Variation of Low GWP Refrigerant Through Expansion Device Using in Heat Pump

Ting Chen,Kyungjin Bae,Dongan Cha,Ohkyung Kwon 대한설비공학회 2018 대한설비공학회 학술발표대회논문집 Vol.2018 No.6