Robert W. Chang

ORCID: 0000-0003-2765-9537
Publications
Citations
Views
---
Saved
---
About
Contact & Profiles
Research Areas
  • Aortic aneurysm repair treatments
  • Cardiac, Anesthesia and Surgical Outcomes
  • Cerebrovascular and Carotid Artery Diseases
  • Cardiovascular Health and Disease Prevention
  • Vascular Procedures and Complications
  • Aortic Disease and Treatment Approaches
  • Acute Ischemic Stroke Management
  • Renal and Vascular Pathologies
  • Peripheral Artery Disease Management
  • Advanced Adaptive Filtering Techniques
  • Blind Source Separation Techniques
  • Intracranial Aneurysms: Treatment and Complications
  • Neonatal Respiratory Health Research
  • Oropharyngeal Anatomy and Pathologies
  • Intraoperative Neuromonitoring and Anesthetic Effects
  • Spinal Fractures and Fixation Techniques
  • Facial Nerve Paralysis Treatment and Research
  • Congenital Diaphragmatic Hernia Studies
  • Optimal Power Flow Distribution
  • Trigeminal Neuralgia and Treatments
  • Speech and Audio Processing
  • Power Line Communications and Noise
  • Advanced Scientific and Engineering Studies
  • Advancements in PLL and VCO Technologies
  • Power System Optimization and Stability

Kaiser Permanente
2018-2025

Colorado Permanente Medical Group
2014-2024

University of Pittsburgh Medical Center
2020-2023

Wellesley College
2023

Kaiser Permanente San Francisco Medical Center
2014-2022

University of California, San Francisco
2019-2022

Neurological Surgery
2020-2021

University of Pittsburgh
2020-2021

Hawaii Permanente Medical Group
2019

Kaiser Permanente San Diego Medical Center
2019

This paper presents a principle of orthogonal multiplexing for transmitting number data messages simultaneously through linear band-limited transmission medium at maximum rate without interchannel and intersymbol interferences. A general method is given synthesizing an infinite classes time functions in limited frequency band. Stated practical terms, the permits synthesis large class filter characteristics arbitrarily amplitude characteristic medium. Rectangular-shaped ideal filters are not...

10.1002/j.1538-7305.1966.tb02435.x article EN Bell System Technical Journal 1966-12-01

This paper presents a theoretical analysis of the performance an orthogonal multiplexing data transmission scheme (parallel scheme) subject to number degrading factors normally encountered by practical operating system. The considered jointly are sampling time error, carrier phase offset, and nonideal characteristics transmitting receiving filters. Performance is measured familiar criterion eye opening received signal. A closed-form expression for obtained. It shown that lengthy nonlinear...

10.1109/tcom.1968.1089889 article EN IRE Transactions on Communications Systems 1968-08-01

Optimal management of patients with asymptomatic severe carotid stenosis is uncertain, due to advances in medical care and a lack contemporary data comparing surgical treatment.To estimate stroke outcomes among medically treated who did not undergo intervention.Retrospective cohort study that included 3737 adult participants (70%-99%) diagnosed between 2008 2012 no prior intervention or ipsilateral neurologic event the 6 months. Participants received follow-up through 2019, all were members...

10.1001/jama.2022.4835 article EN JAMA 2022-05-24

Objective: Tardive dyskinesia is a movement disorder affecting 20%–40% of patients treated chronically with neuroleptic drugs. The dopamine supersensitivity hypothesis cannot account for the time course tardive or persistence and associated structural changes after neuroleptics are discontinued. authors hypothesized that enhance striatal glutamatergic neurotransmission by blocking presynaptic receptors, which causes neuronal damage as consequence oxidative stress.Method: CSF was obtained...

10.1176/ajp.155.9.1207 article EN American Journal of Psychiatry 1998-09-01

Short-term results of superficial femoral artery and popliteal percutaneous transluminal angioplasty have been good, but long-term factors influencing patency are less commonly reported. One hundred thirty-seven angioplasties with follow-up for 54 months were reviewed. The 4-year stenoses was 61% occlusions 68%. If the initial result clinically successful, not influenced by quality or runoff length occlusion. Nineteen patients returned redilatation, eight whom had developed new lesions....

10.2214/ajr.146.5.1025 article EN American Journal of Roentgenology 1986-05-01

Rupture after abdominal endovascular aortic aneurysm repair (EVAR) is a function of graft maintenance the seal and fixation. We describe our 10-year experience with rupture EVAR.From 2000 to 2010, 1736 patients (AAA) from 17 medical centers underwent EVAR in large, regional integrated health care system. Preoperative demographic clinical data interest were collected stored registry. retrospectively identified postoperative rupture, characterized as "early" "delayed" (≤30 days >30 initial...

10.1016/j.jvs.2014.05.046 article EN publisher-specific-oa Journal of Vascular Surgery 2014-06-20

The risk of adverse events from ascending thoracic aorta aneurysm (TAA) is poorly understood but drives clinical decision-making.To evaluate the association TAA size with outcomes in nonsyndromic patients a large non-referral-based health care delivery system.The Kaiser Permanente Thoracic Aortic Aneurysm (KP-TAA) cohort study was retrospective at Northern California, fully integrated system insuring and providing for more than 4.5 million persons. Nonsyndromic regional safety net tracking...

10.1001/jamacardio.2022.3305 article EN JAMA Cardiology 2022-10-05

OBJECTIVE/SUMMARY BACKGROUND DATA: Serial transverse enteroplasty (STEP) is a new intestinal lengthening procedure that has been shown to clinically increase bowel length. This study examined the impact of STEP upon function in model short syndrome.Young pigs (n=10) had reversed segment interposed induce dilatation. Five underwent 90% resection with on remaining dilated while 5 served as controls and without procedure. Determinations nutritional status, absorptive capacity, bacterial...

10.1097/01.sla.0000197704.76166.07 article EN Annals of Surgery 2006-01-20

The use of transversal filters for automatic equalization has made possible high-speed data communication over voiceband telephone channels. Recently much attention been focused on the sets in private line multiparty polling systems. However, such applications, it is necessary to reduce start-up time present equalizer drastically. This paper examines (settling time) filter two important classes systems: Class IV partial-response systems and single-sideband Nyquist (The latter represents...

10.1002/j.1538-7305.1971.tb02591.x article EN Bell System Technical Journal 1971-07-08

Abstract Background Clinical determination of patients at high risk poor surgical outcomes is complex and may be supported by clinical tools to summarize the patient’s own personalized electronic health record (EHR) history vitals data through predictive models. Since prior models were not readily available for EHR-integration, our objective was develop validate a stratification tool, named Assessment Geriatric Emergency Surgery (AGES) score, predicting 30-day major postoperative...

10.1186/s12871-024-02880-4 article EN cc-by BMC Anesthesiology 2025-01-27

Fault equivalence is an essential concept in digital design with significance fault diagnosis, diagnostic test generation, testability analysis and logic synthesis. In this paper, efficient algorithm to check whether two faults are equivalent presented. If they not equivalent, the returns a vector that distinguishes them. The proposed approach complete since for every pair of it either proves or distinguishing vector. This performed simple hardware construction sequence simulation/ATPG-based...

10.1109/iscas.2004.1329502 article EN 2004-11-30
Coming Soon ...