bluuebunny/crossref_metadata_2025 huggingface dataset:
Statistical Analysis of Pc1 Pulsations Observed by a BOH Magnetometer
Authors: Kim Jiwoo , Hwang Junga , Kim Hyangpyo , Yi Yu
Published: May 2023

Pc1 pulsations are important to consider for the interpretation of wave-particle
interactions in the Earth’s magnetosphere. In fact, the wave properties of these
pulsations change dynamically when they propagate from the source region in the space to
the ground. A detailed study of the wave features can help understanding their time
evolution mechanisms. In this study, we statistically analyzed Pc1 pulsations observed
by a Bohyunsan (BOH) magneto-impedance (MI) sensor located in Korea (L = 1.3) for ~one
solar cycle (November 2009-August 2018). In particular, we investigated the temporal
occurrence ratio of Pc1 pulsations (considering seasonal, diurnal, and annual variations
in the solar cycle), their wave properties (e.g., duration, peak frequency, and
bandwidth), and their relationship with geomagnetic activities by considering the Kp and
Dst indices in correspondence of the Pc1 pulsation events. We found that the Pc1 waves
frequently occurred in March in the dawn (1-3 magnetic local time (MLT)) sector, during
the declining phase of the solar cycle. They generally continued for 2-5 minutes,
reaching a peak frequency of ~0.9 Hz. Finally, most of the pulsations have strong
dependence on the geomagnetic storm and observed during the early recovery phase of the
geomagnetic storm.
Simulation Study of Solar Wind Interaction with Lunar Magnetic Fields
Authors: Choi Cheong Rim , Dokgo Kyunghwan , Woo Chang Ho , Min Kyoung Wook
Published: May 2023

Particle-in-cell simulations were performed to understand the interaction of the
solar wind with localized magnetic fields on the sunlit surface of the Moon. The results
indicated a mini-magnetosphere was formed which had a thin magnetopause with the
thickness of the electron skin depth. It was also found that the solar wind penetrated
into the cavity of the magnetosphere intermittently rather than in a steady manner. The
solar wind that moved around the magnetosphere was observed to hit the surface of the
Moon, implying that it may be the cause of the lunar swirl formation on the surface.
Investigation of Ionospheric Earthquake Precursors Using US-TEC Data during the
Solar Maximum of 2013–2015
Authors: Park Jeongchan , Park Sun Mie
Published: May 2023

Recent studies have suggested that detectable ionospheric disturbances precede
earthquakes. In the present study, variations in the vertical total electron content
(TEC) for eight earthquakes with magnitudes of M ≥ 5.5 in the western United States were
investigated during the solar maximum of 2013–2015 using United States total electron
content (US-TEC) data provided by the National Oceanic and Atmospheric Administration.
Analyses of 12 earthquakes with magnitudes of 5.0 ≤ M < 5.5 in the same region were
also performed. The TEC variations were examined for 40 days, including the times when
the earthquakes occurred. The results indicated a correlation between earthquakes with
magnitudes of M ≥ 5.0 and ionospheric TEC anomalies. TEC anomalies occurred before 60%
of the earthquakes. Additionally, they were more frequently observed for large
earthquakes (75%, M ≥ 5.5) than for small earthquakes (50%, 5.5 > M ≥ 5.0). Anomalous
increases in the TEC occurred 2–18 days before the earthquakes as an ionospheric
precursor, whereas solar and geomagnetic activities were low or moderate.
Vertical Structures of Temperature and Ozone Changes in the Stratosphere and
Mesosphere during Stratospheric Sudden Warmings
Authors: Kim Jeong-Han , Jee Geonhwa , Choi Hyesun , Kim Baek-Min , Kim Seong-Joong
Published: May 2023

We analyze the observations of temperature and ozone measured by the Microwave
Limb Sounder (MLS) during the period of 2005–2016, to investigate the vertical
structures of temperature and ozone in the stratosphere and mesosphere during
stratospheric sudden warming (SSW). We compute the height profiles of the correlation
coefficients between 55 height levels of MLS temperature anomalies and compare them with
the results of Whole Atmosphere Community Climate Model simulations for three major
SSWs. We also construct the temperature and ozone anomalies for the events to
investigate the changes in the temperature and ozone distributions with height. There
seems to always be a relatively weak but broad negative correlation between the
temperature anomaly at 10 hPa and temperature anomalies over the entire mesosphere
during the period before SSW events. However, this pattern gets stronger in the lower
mesosphere but becomes a positive correlation in the upper mesosphere and lower
thermosphere after the onset of SSW. We also found that the temperatures from the
simulations show a similar trend to the observational results but with smaller
variations and the transition height from negative to positive correlation in the
mesosphere is much lower in the simulation than in the actual observations.
Space Surveillance Radar Observation Analysis: One-Year Tracking and Orbit
Determination Results of KITSAT-1, “우리별 1호”
Authors: Choi Jin , Jo Jung Hyun , Choi Eun-Jung , Yu Jiwoong , Choi Byung-Kyu , Kim Myung-Jin , Yim Hong-Suh , Roh Dong-Goo , Kim Sooyoung , Park Jang-Hyun , Cho Sungki
Published: May 2023

The Korean Institute of Technology Satellite (KITSAT-1) is the first satellite
developed by the Satellite Technology Research Center and the University of Surrey.
KITSAT-1 is orbiting the Earth’s orbit as space debris with a 1,320 km altitude after
the planned mission. Due to its relatively small size and altitude, tracking the
KITSAT-1 was a difficult task. In this research, we analyzed the tracking results of
KITSAT-1 for one year using the Midland Space Radar (MSR) in Texas and the Poker Flat
Incoherent Scatter Radar (PFISR) in Alaska operated by LeoLabs, Inc. The tracking
results were analyzed on a weekly basis for MSR and PFISR. The observation was conducted
by using both stations at an average frequency of 10 times per week. The overall
corrected range measurements for MSR and PFISR by LeoLabs were under 50 m and 25 m,
respectively. The ionospheric delay, the dominant error source, was confirmed with the
International Reference of Ionosphere-16 model and Global Navigation Satellite System
data. The weekly basis orbit determination results were compared with two-line element
data. The comparison results were used to confirm the orbital consistency of the
estimated orbits.
Creating and Transforming a Second-Rank Antisymmetric Field-Strength Tensor Fαβ in
Minkowski Space using MATHEMATICA
Authors: Kim Bogyeong , Yun Hee-Joong
Published: May 2023

As the laws of physics are expressed in a manner that makes their invariance
under coordinate transformations manifest, they should be written in terms of tensors.
Furthermore, tensors make manifest the characteristics and behaviors of electromagnetic
fields through inhomogeneous, anisotropic, and compressible media. Electromagnetic
fields are expressed completely in tensor form, Fαβ, which implies both electric field E
→ and magnetic field B → rather than separately in the vector fields. This study
presents the Mathematica platform that generates and transforms a second-rank
antisymmetric field-strength tensor Fαβ and whiskbroom pattern in Minkowski space. The
platforms enhance the capabilities of students and researchers in tensor analysis and
improves comprehension of the elegant features of complete structure in physics.
The Chemical Composition of V1719 Cyg: δ Scuti Type Star without the Accretion of
Interstellar Matter
Authors: Yushchenko Alexander V. , Kim Chulhee , Jeong Yeuncheol , Doikov Dmytry N. , Yushchenko Volodymyr A. , Khrapatyi Sergii V. , Demessinova Aizat
Published: May 2023

High resolution spectroscopic observation of V1719 Cyg were made at 1.8 meter
telescope of Bohyunsan Optical Astronomy observatory in Korea. Spectral resolving power
was R=45,000, signal to noise ratio S/N>100. The abundances of 28 chemical elements
from carbon to dysprosium were found with the spectrum synthesis method. The abundances
of oxygen, titanium, vanadium and elements with Z>30 are overabundant by 0.2–0.9 dex
with respect to the solar values. Correlations of derived abundances with condensation
temperatures and second ionization potentials of these elements are discussed. The
possible influence of accretion from interstellar environment is not so strong as for ρ
Pup and other stars with similar temperatures. The signs of accretion are absent. The
comparison of chemical composition with solar system r- & s-process abundance
patterns shows the enhancement of the photosphere by s-process elements.
A Development of Docking Phase Analysis Tool for Nanosatellite
Authors: Jeong Miri , Cho Dong-Hyun , Kim Hae-Dong
Published: May 2023

In order to avoid the high cost and high risk of demonstration mission of
rendezvous-docking technology, missions using nanosatellites have recently been
increasing. However, there are few successful mission cases due to many limitations of
nanosatellites like small size, power limitation, and limited performances of sensor,
thruster, and controller. To improve the probability of rendezvous-docking mission
success using nanosatellite, a rendezvous-docking phase analysis tool for nanosatellites
is developed. The tool serves to analyze the relative position and attitude control of
the chaser satellite at the docking phase. In this tool, the Model Predictive Controller
(MPC) is implemented as a controller, and Extended Kalman Filter (EKF) is adopted as a
filter for noise filtering. To verify the performance and effectiveness of the developed
tool for nanosatellites, simulation study was conducted. Consequently, we confirmed that
this tool can be used for the analysis of relative position and attitude control for
nanosatellites in the rendezvous-docking phase.
Initial Operation and Preliminary Results of the Instrument for the Study of
Stable/Storm-Time Space (ISSS) on Board the Next Generation Small Satellite-1
(NEXTSat-1)
Authors: Kim Eojin , Yoo Ji-Hyeon , Kim Hee-Eun , Seo Hoonkyu , Ryu Kwangsun , Sohn Jongdae , Lee Junchan , Seon Jongho , Lee Ensang , Lee Dae-Young , Min Kyoungwook , Kang Kyung-In , Lee Sang-Yun , Kang Juneseok
Published: May 2023

This paper describes the initial operations and preliminary results of the
Instrument for the study of Stable/Storm-time Space (ISSS) onboard the microsatellite
Next Generation Small Satellite-1 (NEXTSat-1), which was launched on December 4, 2018
into a sun-synchronous orbit at an altitude of 575 km with an orbital inclination angle
of 97.7°. The spacecraft and the instruments have been working normally, and the results
from the observations are in agreement with those from other satellites. Nevertheless,
improvement in both the spacecraft/instrument operation and the analysis is suggested to
produce more fruitful scientific results from the satellite operations. It is expected
that the ISSS observations will become the main mission of the NEXTSat-1 at the end of
2020, when the technological experiments and astronomical observations terminate after
two years of operation.
Performance Analysis of M-ary Optical Communication over Log-Normal Fading Channels for CubeSat Platforms
Authors: Lim Hyung-Chul , Yu Sung-Yeol , Sung Ki-Pyoung , Park Jong Uk , Choi Chul-Sung , Choi Mansoo
Published: May 2023

A CubeSat platform has become a popular choice due to inexpensive commercial off-the-shelf (COTS) components and low launch cost. However, it requires more power-efficient and higher-data rate downlink capability for space applications related to remote sensing. In addition, the platform is limited by the size, weight and power (SWaP) constraints as well as the regulatory issue of licensing the radio frequency (RF) spectrum. The requirements and limitations have put optical communications on promising alternatives to RF communications for a CubeSat platform, owing to the power efficiency and high data rate as well as the license free spectrum. In this study, we analyzed the performance of optical downlink communications compatible with CubeSat platforms in terms of data rate, bit error rate (BER) and outage probability. Mathematical models of BER and outage probability were derived based on not only the log-normal model of atmospheric turbulence but also a transmitter with a finite extinction ratio. Given the fixed slot width, the optimal guard time and modulation orders were chosen to achieve the target data rate. And the two performance metrics, BER and outage data rate, were analyzed and discussed with respect to beam divergence angle, scintillation index and zenith angle.
Recovery of Asteroids from Observations of Too-Short Arcs by Triangulating Their
Admissible Regions
Authors: Espitia Daniela , Quintero Edwin A. , Parra Miguel A.
Published: May 2023

The data set collected during the night of the discovery of a minor body
constitutes a too-short arc (TSA), resulting in failure of the differential correction
procedure. This makes it necessary to recover the object during subsequent nights to
gather more observations that will allow a preliminary orbit to be calculated. In this
work, we present a recovery technique based on sampling the admissible region (AdRe) by
the constrained Delaunay triangulation. We construct the AdRe in its topocentric and
geocentric variants, using logarithmic and exponential metrics, for the following
near-Earth-asteroids: (3122) Florence, (3200) Phaethon, 2003 GW, (1864) Daedalus, 2003
BH84 and 1977 QQ5; and the main-belt asteroids: (1738) Oosterhoff, (4690) Strasbourg,
(555) Norma, 2006 SO375, 2003 GE55 and (32811) Apisaon. Using our sampling technique, we
established the ephemeris region for these objects, using intervals of observation from
25 minutes up to 2 hours, with propagation times from 1 up to 47 days. All these objects
were recoverable in a field of vision of 95’ × 72’, except for (3122) Florence and
(3200) Phaethon, since they were observed during their closest approach to the Earth. In
the case of 2006 SO375, we performed an additional test with only two observations
separated by 2 minutes, achieving a recovery of up to 28 days after its discovery, which
demonstrates the potential of our technique.
Ionization of Hydrogen in the Solar Atmosphere
Authors: Chae Jongchul
Published: May 2023

The ionization degree of hydrogen is crucial in the physics of the plasma in the
solar chromosphere. It specifically limits the range of plasma temperatures that can be
determined from the Hα line. Given that the chromosphere greatly deviates from the local
thermodynamic equilibrium (LTE) condition, precise determinations of hydrogen ionization
require the solving of the full set of non-LTE radiative transfer equations throughout
the atmosphere, which is usually a formidable task. In many cases, it is still necessary
to obtain a quick estimate of hydrogen ionization without having to solve for the
non-LTE radiative transfer. Here, we present a simple method to meet this need. We adopt
the assumption that the photoionizing radiation field changes little over time, even if
physical conditions change locally. With this assumption, the photoionization rate can
be obtained from a published atmosphere model and can be used to determine the degree of
hydrogen ionization when the temperature and electron density are specified. The
application of our method indicates that in the chromospheric environment, plasma
features contain more than 10% neutral hydrogen at temperatures lower than 17,000 K but
less than 1% neutral hydrogen at temperatures higher than 23,000 K, implying that the
hydrogen temperature determined from the Hα line is physically plausible if it is lower
than 20,000 K, but may not be real, if it is higher than 25,000 K. We conclude that our
method can be readily exploited to obtain a quick estimate of hydrogen ionization in
plasma features in the solar chromosphere.
Resonance Capture for a Mercurian Orbiter in the Vicinity of Sun
Authors: Khattab Elamira Hend , Abd El-Salam Fawzy Ahmed , Rahoma Walid A.
Published: May 2023

In this work, the problem of resonance caused by some gravitational potentials
due to Mercury and a third body, namely the Sun, together with some non-gravitational
perturbations, specifically coronal mass ejections and solar wind in addition to
radiation pressure, are investigated. Some simplifying assumptions without loss of
accuracy are employed. The considered force model is constructed. Then the Delaunay
canonical set is introduced. The Hamiltonian of the problem is obtained then it is
expressed in terms of the Deluanay canonical set. The Hamiltonian is re-ordered to adopt
it to the perturbation technique used to solve the problem. The Lie transform method is
surveyed. The Hamiltonian is doubly averaged. The resonance capture is investigated.
Finally, some numerical simulations are illustrated and are analyzed. Many resonant
inclinations are revealed.
The Possible Signs of Hydrogen and Helium Accretion from Interstellar Medium on the
Atmospheres of F-K Giants in the Local Region of the Galaxy
Authors: Yushchenko Alexander , Kim Seunghyun , Jeong Yeuncheol , Demessinova Aizat , Yushchenko Volodymyr , Doikov Dmytry , Gopka Vira , Jeong Kyung Sook , Rittipruk Pakakaew
Published: May 2023

The dependencies of the chemical element abundances in stellar atmospheres with
respect to solar abundances on the second ionization potentials of the same elements
were investigated using the published stellar abundance patterns for 1,149 G and K
giants in the Local Region of the Galaxy. The correlations between the relative
abundances of chemical elements and their second ionization potentials were calculated
for groups of stars with effective temperatures between 3,764 and 7,725 K. Correlations
were identified for chemical elements with second ionization potentials of 12.5 eV to 20
eV and for elements with second ionization potentials higher than 20 eV. For the first
group of elements, the correlation coefficients were positive for stars with effective
temperatures lower than 5,300 K and negative for stars with effective temperatures from
5,300 K to 7,725 K. The results of this study and the comparison with earlier results
for hotter stars confirm the variations in these correlations with the effective
temperature. A possible explanation for the observed effects is the accretion of
hydrogen and helium atoms from the interstellar medium.
Design of Regional Coverage Low Earth Orbit (LEO) Constellation with Optimal
Inclination
Authors: Shin Jinyoung , Park Sang-Young , Son Jihae , Song Sung-Chan
Published: May 2023

In this study, we describe an analytical process for designing a low Earth orbit
constellation for discontinuous regional coverage, to be used for a surveillance and
reconnaissance space mission. The objective of this study was to configure a satellite
constellation that targeted multiple areas near the Korean Peninsula. The constellation
design forms part of a discontinuous regional coverage problem with a minimum revisit
time. We first introduced an optimal inclination search algorithm to calculate the
orbital inclination that maximizes the geometrical coverage of single or multiple ground
targets. The common ground track (CGT) constellation pattern with a repeating period of
one nodal day was then used to construct the rest of the orbital elements of the
constellation. Combining these results, we present an analytical design process that
users can directly apply to their own situation. For Seoul, for example, 39.0° was
determined as the optimal orbital inclination, and the maximum and average revisit times
were 58.1 min and 27.9 min for a 20-satellite constellation, and 42.5 min and 19.7 min
for a 30-satellite CGT constellation, respectively. This study also compares the revisit
times of the proposed method with those of a traditional Walker-Delta constellation
under three inclination conditions: optimal inclination, restricted inclination by
launch trajectories from the Korean Peninsula, and inclination for the sun-synchronous
orbit. A comparison showed that the CGT constellation had the shortest revisit times
with a non-optimal inclination condition. The results of this analysis can serve as a
reference for determining the appropriate constellation pattern for a given inclination
condition.
Characteristics of Horizontal Winds in the Mesosphere and Lower Thermosphere Region
over Korean Peninsula Observed from the Korea Astronomy and Space Science Institute
Meteor Radar
Authors: Kam Hosik , Kwak Young-Sil , Yang Tae-Yong , Kim Yong Ha , Kim Jeongheon , Lee Jaewook , Choi Seonghwan , Baek Ji-Hye
Published: May 2023

We present for the first time the characteristics of upper atmospheric horizontal
winds over the Korean Peninsula. Winds and their variability are derived using four-year
measurements by the Korea Astronomy and Space Science Institute (KASI) meteor radar. A
general characteristic of zonal and meridional winds is that they exhibit distinct
diurnal and seasonal variations. Their changes indicate sometimes similar or sometimes
different periodicities. Both winds are characterized by either semi-diurnal tides (12
hour period) and/or diurnal tides (24 hour period) from 80–100 km. In terms of annual
change, the annual variation is the strongest component in both winds, but semi-annual
and ter-annual variations are only detected in zonal winds.
Moment of Inertia of Gas as a Source of Added Gravitational Field in
Galaxies
Authors: Portnov Yuriy A.
Published: May 2023

In this paper we propose a new perspective for explaining galaxy rotation curves.
We conjecture that there is a gravitational moment of inertia which, together with
gravitational mass, contributes to the gravitational potential. We substantiate a
formula for the potential created by the moment of inertia. We validate our model by
computing orbital rotation velocities for several galaxies and showing that computed
rotation velocities correspond to the observed ones. Our proposed approach is capable of
accounting for constant gas velocities outside of a galactic disc without relying on the
dark matter hypothesis. Furthermore, it addresses several problems faced by the
application of the dark matter hypothesis, e.g., the absence of inward collapse of dark
matter into a galaxy, the spherical distribution of dark matter around galaxies, and
absence of traces of the effect of dark matter in two ultra-diffuse galaxies, NGC
1052-DF2, and NGC 1052-DF4.
Science Objectives and Design of Ionospheric Monitoring Instrument Ionospheric Anomaly Monitoring by Magnetometer And Plasmaprobe (IAMMAP) for the CAS500-3 Satellite
Authors: Ryu Kwangsun , Lee Seunguk , Woo Chang Ho , Lee Junchan , Jang Eunjin , Hwang Jaemin , Kim Jin-Kyu , Cha Wonho , Kim Dong-guk , Koo BonJu , Park SeongOg , Choi Dooyoung , Choi Cheong Rim
Published: May 2023

The Ionospheric Anomaly Monitoring by Magnetometer And Plasma-probe (IAMMAP) is one of the scientific instruments for the Compact Advanced Satellite 500-3 (CAS 500-3) which is planned to be launched by Korean Space Launch Vehicle in 2024. The main scientific objective of IAMMAP is to understand the complicated correlation between the equatorial electro-jet (EEJ) and the equatorial ionization anomaly (EIA) which play important roles in the dynamics of the ionospheric plasma in the dayside equator region. IAMMAP consists of an impedance probe (IP) for precise plasma measurement and magnetometers for EEJ current estimation. The designated sun-synchronous orbit along the quasi-meridional plane makes the instrument suitable for studying the EIA and EEJ. The newly-devised IP is expected to obtain the electron density of the ionosphere with unprecedented precision by measuring the upper-hybrid frequency (fUHR) of the ionospheric plasma, which is not affected by the satellite geometry, the spacecraft potential, or contamination unlike conventional Langmuir probes. A set of temperaturetolerant precision fluxgate magnetometers, called Adaptive In-phase MAGnetometer, is employed also for studying the complicated current system in the ionosphere and magnetosphere, which is particularly related with the EEJ caused by the potential difference along the zonal direction.
Spectral Deconvolution Analysis of Mafic Mineral in Irregular Mare Patches on the
Moon
Authors: Hong Ik-Seon , Yi Yu , Park Nuri
Published: May 2023

Irregular mare patches (IMPs), recently discovered on the Moon, are eruptions of
magma on the lunar surface, and their origins are still in question. While prior studies
on IMPs have mainly focused on optical image analysis, in this study, an analysis of the
characteristics of minerals is performed exemplary for the first time. Modified Gaussian
model (MGM) deconvolution was applied to the infrared spectrum to confirm the properties
of the mafic mineral. Mafic minerals were analyzed for 6 olivine-rich (Ol-rich) IMPs out
of 91 currently reported, and only 4 of them yielded results of significance. All four
sites showed more abundance of Fe than Mg, and manifested a weak relationship with
Mg-suite rock. However, a problem was discovered during the MGM application process due
to pilot implementation. In order to solve this problem, it is required to adjust the
MGM initial condition settings more precisely and to increase the signal to noise ratio
of the observation data. Moreover, it is necessary to analyze the mineral properties for
all IMPs considering minerals other than Ol and utilize them to deduce the origin of the
IMPs.
Energetic Electron and Proton Interactions with Pc5 Ultra Low Frequency (ULF) Waves
during the Great Geomagnetic Storm of 15–16 July 2000
Authors: Lee Eunah , Mann Ian R. , Ozeke Louis G.
Published: May 2023

The dynamics of the outer zone radiation belt has received a lot of attention
mainly due to the correlation between the occurrence of enhancing relativistic electron
flux and spacecraft operation anomalies or even failures (e.g., Baker et al. 1994).
Relativistic electron events are often observed during great storms associated with
ultra low frequency (ULF) waves. For example, a large buildup of relativistic electrons
was observed during the great storm of March 24, 1991 (e.g., Li et al. 1993; Hudson et
al. 1995; Mann et al. 2013). However, the dominant processes which accelerate
magnetospheric radiation belt electrons to MeV energies are not well understood. In this
paper, we present observations of Pc5 ULF waves in the recovery phase of the Bastille
day storm of July 16, 2000 and electron and proton flux simultaneously oscillating with
the same frequencies as the waves. The mechanism for the observed electron and proton
flux modulations is examined using groundbased and satellite observations. During this
storm time, multiple packets of discrete frequency Pc5 ULF waves appeared associated
with energetic particle flux oscillations. We model the drift paths of electrons and
protons to determine if the particles drift through the ULF wave to understand why some
particle fluxes are modulated by the ULF waves and others are not. We also analyze the
flux oscillations of electrons and protons as a function of energy to determine if the
particle modulations are caused by a ULF wave drift resonance or advection of a particle
density gradient. We suggest that the energetic electron and proton modulations by Pc5
ULF waves provide further evidence in support of the important role that ULF waves play
in outer radiation belt dyanamics during storm times.
Korea Pathfinder Lunar Orbiter Flight Dynamics Simulation and Rehearsal Results for Its Operational Readiness Checkout
Authors: Song Young-Joo , Bae Jonghee , Hong SeungBum , Bang Jun
Published: May 2023

Korea Pathfinder Lunar Orbiter (KPLO), also known as Danuri, was successfully launched on 4 Aug. from Cape Canaveral Space Force Station using a Space-X Falcon-9 rocket. Flight dynamics (FD) operational readiness was one of the critical parts to be checked before the flight. To demonstrate FD software’s readiness and enhance the operator’s contingency response capabilities, KPLO FD specialists planned, organized, and conducted four simulations and two rehearsals before the KPLO launch. For the efficiency and integrity of FD simulation and rehearsal, different sets of blind test data were prepared, including the simulated tracking measurements that incorporated dynamical model errors, maneuver execution errors, and other errors associated with a tracking system. This paper presents the simulation and rehearsal results with lessons learned for the KPLO FD operational readiness checkout. As a result, every functionality of FD operation systems is firmly secured based on the operation procedure with an enhancement of contingency operational response capability. After conducting several simulations and rehearsals, KPLO FD specialists were much more confident in the flight teams’ ability to overcome the challenges in a realistic flight and FD software’s reliability in flying the KPLO. Moreover, the results of this work will provide numerous insights to the FD experts willing to prepare deep space flight operations.
Report of the WFNS Global Relations Committee
Authors: Boop Frederick , Shlobin Nathan A.
Published: May 2023

Thank you for the opportunity to serve on this committee.  It appears the WFNS has assembled an all-star cast of neurosurgeons interested in Global Neurosurgery.  I am honored to serve as External Relations Lead.  Listed below are a few examples of projects the group is working on that fit with your deliverables (specific, measurable, achievable, relevant, time-based).  I look forward to learning of other initiatives from the group as we develop synergies moving forward.

 

It was noted that both the WFNS and the ISPN have Education Committees who produce educational courses either virtually or in person in various LMICs several times per year. I have spoken to President Oyesiku and Kenon Arnautovic, the Chair of Chairs, suggesting that rather than having two parallel processes performing the same task, that we consolidate these committees and have the ISPN serve as the Pediatric Neurosurgery Education Committee for the WFNS hence forth.  Typically, in the past, the Committee chairs have been ISPN members.  Both Nelson and Kenon have voiced agreement to that arrangement.  Since the ISPN is already an international society with 530 members from around the globe, this should be acceptable without the ISPN having to “join” the WFNS.  The agreement was that if any course produced a financial profit, those monies would be divided equally between the WFNS and the ISPN.  To date, the ISPN has underwritten the costs of plane tickets for the speakers at these meetings, although the courses have all been virtual since the COVID pandemic.  The local hosts have covered the costs of hotel, meals, etc. once the speakers are on location.  To date I am not aware of any of these courses that have generated a financial profit.  Obviously, the marketing and presentations at these teaching courses would be co-branded.
Interface of Global Neurosurgery and Technological Innovation:
Authors: Barkley Ariana , Lepard Jacob , Vaca Silvia
Published: May 2023

.
EFFECT OF COVID-19 PANDEMIC ON WAITING TIMES OF PATIENTS FOR ELECTIVE SURGERIES IN LAHORE GENERAL HOSPITAL: A CROSS SECTIONAL STUDY
Authors: Falak Sher  , Muhammad Ayaz  , Zahid Sattar  , Muhammad Azam  , Nouman Anees  , Asfaa Ashfaq
Published: May 2023

Background: This cross-sectional study focused on delay in elective surgeries during the 1st wave (May to July, 2020) and 2nd wave (Nov to Dec, 2020) of Covid-19 pandemic. Primary aim of this research was to find out the effects of Covid-19 restrictions on patients who presented and got selected for elective surgeries in Lahore General Hospital. Amid Covid-19 there was either postponement or reduction in elective surgery lists causing a huge buildup of patients waiting for surgery.Objectives: To establish weather Covid-19 pandemic adversely affected patients on elective surgeries by increasing gap period between presentation and elective procedure.Methods: Data for elective surgery lists were gathered from Lahore General Hospital for two years 2019 and 2020. All surgical procedures performed and cases postponed were noted for both years. Then data from year 2020 (Covid-19 era) was compared to reference year 2019 (pre-Covid era). The patients per list, total patients, their means and frequencies of the most common surgical procedures were calculated separately.Results: A total of 750 surgeries were included in the study from Covid-19 affected months of 2020 and respective months of 2019. The increased waiting time of patients resulted in an average 38.9% decrease in cases per list in 2020 as compared with 2019. Frequency of elective procedures started declining rapidly with the onset of lock down in the first covid-19 wave from mid-April to early May 2020. This reached a maximum in late May and June due to buildup of more and more deferred cases. In mid-July 2020 and thereafter there were “smart lockdowns” with partial restrictions, but elective surgeries still remained lagging far behind as compared with 2019.Conclusion: Coved-19 pandemic posed a heavy strain on the health care system with elective surgery waiting times increased by as much as 3-5 times in some cases. Even though the elective surgery turnover was increased by one-fifth as a compensation after imposition of “smart lockdown”. This delay also led to a reported increased morbidity and mortality during the lock down era in 2020.
تقييم أداء المصارف التجارية باستخدام نموذج CAMEL دراسة تطبيقية علي عينة من المصارف البحرينية خلال الفترة (2013-2020)
Authors: سعد محمد علي بلقاسم , يحي سالم احمد محمد
Published: May 2023

تهدف الدراسة لاستخدام نموذج "CAMEL" في تقييم الأداء المالي لعينة من المصارف التجارية البحرينية حيت تم الاعتماد على تجميع البيانات من خلال التقارير المالية السنوية للمصارف البحرينية لاستخدامها لحساب بعض النسب الهامة لتقييم أداء المصارف, واعتمدت الدراسة من خلال إتباع المنهج التحليلي خلال الفترة 2013--2020م. وذلك للوقوف على نقاط القوة والضعف فيها . ومن أهم النتائج التي تم التوصل إليها أن عدد المصارف المصنفة كأفضل أداء مالي (قوي) تمثلت في مصرف واحد فقط وهو (الخليج)، أما المصارف ذات الأداء غير المرضي تمثلت في مصرف (المتحد) أما باقي المصارف فاعتبرت مصارف ذات الأداء المالي المعقول،  وفي ضوء نتائج الدراسة فإننا نوصي بالعمل علي إلزام تطبيق المصارف بمراجعة مستوي أداء عملياتها المالية والمصرفية من خلال تطبيق عناصر نموذج التقييم المصرفي بشكل مستمر ومراقبه أوضاع المصارف المتعثرة من خلال متابعة اتجاه النسب المالية التي تعكس نسب ملاءة رأس المال, القدرة على السداد وكفاءة الإدارة في تشغيل الأصول المتاحة و العمل علي تطوير آليات تطبيق مكونات نموذج التقييم CAMEL.
The Effect of Quenching Media on the Hardness of Low Carbon Steel
Authors: طه عبد الله  , عبد الحكيم بن مسكين  , محمد المدني
Published: May 2023

Steels with desired properties are essential and always required by many industries. This paper highlights some heat treatment operations with various cooling media to achieve different rapid cooling rates. This was carried out by heating samples of low carbon steel to a specific temperature and then cooling them rapidly in 8 different quenching media in order to obtain a specific microstructure of steel. These heat-treated samples were then tested mechanically using the Brinell hardness test (BH). The results show that the quenching mediums affect the mechanical properties and hence the microstructures of low carbon steels and the effect varies depending on the types of quanchants employed.
تأثير عمليات العرض، التسويق والتصنيع على تركيز الهستامين في بعض انواع الأسماك
Authors: احميده الغراري الزقطاط  , هاجر عمر التومي
Published: May 2023

تعتبر عمليات تصنيع وتعليب المنتجات السمكية مثل التونة، السردين والماكريل من الصناعات الغذائية الهامة، حيث تستهلك بكميات كبيرة محلياً وعالمياً، وذلك بسبب مكوناتها الغذائية الجيدة إضافة الى سهولة تجهيزها وتحضيرها، إلا أنها قد تتسبب أحياناً في حدوث بعض حالات التسمم للمستهلك مثل حالات التسمم بالهستامين، وهو أحد أهم المخاطر والتحديات التي تواجه مصنعي المنتجات السمكية المعلبة والطازجة. تهدف هذه الدراسة في الجزء الأول الى تحديد مدى تأثير خطوات حفظ الأسماك على تركيز الهستامين في المنتجات السمكية بعينات من السردين والماكريل الطازج بأحد المصانع المحلية ومدى مطابقتها للمواصفات القياسية الليبية والعالمية. كما تضمن الجزء الثاني سحب عينات عشوائية من الأسماك الطازجة تونة، سردين وماكريل من سوق السمك بمدينة طرابلس خلال ثلاث فترات: الصباحية، الظهيرة والمسائية بغرض دراسة علاقة تأثير الفترة الزمنية لعرض الأسماك بالسوق وتركيز الهستامين. تم تقدير تركيز الهستامين في العينات بإستخدام تقنية .ELISA كان متوسط تركيز الهستامين في عينات السردين الطازج خلال مراحل التصنيع وهي مرحلة الإستلام، بعد الغسل، نزع الأحشاء والتنظيف والتجميد السريع عند درجة حرارة 40 تحت الصفر المئوي3.39 ،5.53 ، 8.56، 10.19، 12.11 مغ/100غ على التوالي. أما عينات الماكريل فكانت نتائج تركيز الهستامين< 0.02، 0.34، 0.14، 0.63، 3.05 مغ/100غ خلال تلك المراحل على التوالي. اتضح وجود فروق معنوية عند مستوى معنوية 5% بين مرحلتي الإستلام والمنتج النهائي. أما فيما يخص نتائج عينات الأسماك الطازجة من سوق السمك وهي تونة، سردين وماكريل خلال الفترات الثلاثة فتبين ارتفاع تركيز الهستامين وخاصة في الفترة المسائية ووجود فروق معنوية بينها، مما يدل على إن لعمليات تجهيز الأسماك وزيادة فترة العرض دور في زيادة تركيز الهستامين وعليه من الضروري جداً الاهتمام بعمليات النظافة وتقليل فترات العرض والتجهيز وإستخدام نظم إدارة سلامة الأغذية في المصانع وأسواق بيع الأسماك.
التحقق من تأثير عوامل مناولة المواد على مستويات الأداء في المؤسسات الخدمية الليبية- دراسة حالة
Authors: الضبيع فرج فرحات
Published: May 2023

تُرَكز هذه الورقة على التحقق من تأثير مناولة المواد على عوامل الأداء في المؤسسات الخدمية الليبية. الهدف الرئيسي من هذه الورقة هو التأكد من تأثيرات مناولة المواد داخل ميناء الخمس البحري من أجل تحقيق أداء أفضل وكفاءة عالية، وخفضاً للتكاليف. سيتم في هذه الورقة استخدام المنهج الوصفي التحليلي، حيث توضح النتائج المتحصل عليها بأن عامل دور إدارة مناولة المواد في تقليل كافة المصاريف داخل الميناء المستهدف يعتبر العامل الأكثر أهمية من بين كافة العوامل التي تمت دراستها. كذلك يوجد ارتباط موجب قوي بين مناولة المواد وعوامل أداء المؤسسة، باعتبار أن مناولة المواد تُقَلل من تكاليف المناولة ومن المخاطر ، وكذلك من الزمن الغير مُسْتَغَل للعمالة. بناءً على هذه النتائج، يتم اقتراح أعمال بحثية مستقبلية لتحسين عمليات مناولة المواد وكذلك القرارات الفعالة داخل المنظمة باستخدام نماذج المحاكاة.
Incidencia de desnutrición crónica y factores asociados en una cohorte de niños menores de 5 años
Authors: Alulema Moncayo Andres Fernando , Vacas Paredes Karina Paola , Rivadeneira Maria Fernanda , Moncayo Ana Lucía
Published: May 2023

Introducción: La desnutrición crónica es un problema de difícil erradicación con grandes repercusiones en la población infantil. En el Ecuador 1 de cada 5 niños menor de cinco años, presenta desnutrición crónica. El objetivo del presente estudio fue determinar incidencia y factores asociados al desarrollo de desnutrición crónica en una cohorte de niños menores de 5 años durante un periodo de seguimiento de un año, en la provincia de Chimborazo, 2018-2019.

Métodos: Se realizó un estudio de cohorte prospectivo, con seguimiento de 2018-2019. La población estuvo conformada por 1228 niños, de los cuales se tomó una muestra de 138 niños. Se tuvieron en cuenta variables como la edad, sexo, ubicación geográfica, nivel socioeconómico, acceso a servicios de salud, servicios básicos y tierras, prácticas de alimentación, antropometría, desnutrición crónica, talla de la madre, infecciones, y parasitosis. Se calculó el Riesgo Relativo (RR) y sus respectivos intervalos de confianza al 95% usando modelos lineales generalizados (familia binomial).

Resultados: La incidencia de desnutrición crónica fue de 20,3%. Los factores asociados fueron: dificultad para acceder a los servicios de salud [RR: 4.87; IC 95%: 1.89-12.55]; y LME < 6 meses [RR: 3.44, IC 95%: 2.14-5.55].

Conclusiones: La incidencia de desnutrición crónica en menores de cinco años en la provincia Chimborazo es elevada; por lo que se precisa de intervenciones que garanticen el acceso a los servicios de salud y educación nutricional para eliminar este problema de salud.
As confrarias, as elites urbanas e o poder municipal em Évora nos finais da Idade Média
Authors: Bastos Serra Joaquim
Published: May 2023

El artículo parte de una cuestión que es la de saber si las cofradías de la ciudad de Évora tuvieron algún papel en la intensa disputa por el poder que marcó la vida política municipal al final de la época medieval. La pregunta es pertinente si tenemos en cuenta que nos referimos a entidades que tuvieron un fuerte impacto dentro de la comunidad urbana y generaron interacciones que les otorgaron un enorme capital social que podría resultar relevante en diferentes niveles. Este texto constituye una contribución para responder a la pregunta planteada inicialmente, centrándose más particularmente en la relación que las cofradías de Évora mantenían con el poder político municipal y con la élite dirigente. El análisis naturalmente tuvo en cuenta las características de estas instituciones, prestando especial atención a su perfil social, considerando también la realidad política de la ciudad. Un marco en el que destaca el fuerte proceso de oligarquización que se acentuó, sobre todo, a partir de mediados del siglo XIV, lo que no quiere decir que no haya habido disputas por el control del poder municipal. Por el contrario, durante este período hubo una intensa lucha política que obligó a los líderes a transigir en muchos aspectos y a enfrentarse, de diferentes maneras, a la creciente oposición proveniente de algunos sectores de la sociedad excluidos del poder. Es en este contexto político en el que debe entenderse la relevancia de las cofradías, no tanto para quienes se oponían o disputaban el poder, sino, sobre todo, y quizás sorprendentemente, para la propia oligarquía.
Cultural Diffusion from China to Pakistan via the China-Pakistan Economic Corridor: A Study of Mandarin Learning in Gilgit Baltistan of Pakistan
Authors: Ali Tajwar , Sultan Haseena , Alam Aftab
Published: May 2023

The China Pakistan Economic Corridor (CPEC) is an enormous South Asian development initiative, with the Gilgit Baltistan region of Pakistan functioning as its entrance point. This enormous endeavor has caused cultural diffusion from China to Pakistan. CPEC is disseminating the non-material culture of China, which is the language spoken in Pakistan's northern regions, as evidenced by the growing prevalence of Mandarin in Gilgit Baltistan since the 2013 launch of CPEC. This study examined the effect of CPEC on the acquisition of Mandarin in Gilgit Baltistan. After distributing 150 questionnaires to Chinese-studying students in Gilgit Baltistan, we received 126 responses via online Google form and print form. The current data set yielded positive results that supported the preponderance of hypotheses. Using a method involving a confined group discussion, the influence of the Chinese language on local languages was observed, and the results were presented. The findings of this study will aid cultural ambassadors, government officials, and other relevant parties in gaining a better understanding of Pakistanis' attitudes toward acquiring Mandarin and Chinese culture.
Կանաչ տնտեսությունը և դրա ձևավորման խթանումը Հայաստանում / Green Economy And the Promotion of its Formation in Armenia
Authors: GALSTYAN Hamazasp , BADADYAN Gagik
Published: May 2023

The green economy is one of the cornerstones of
ensuring sustainable development and one of the
imperatives for the transformation of the modern world.
It is the green economy that creates opportunities
for long-term development. In this case, it is within
the powers of the state and local self-government
bodies of any country to promote its formation and
subject the country to the green transformation. The
Republic of Armenia is not an exception. However, what
the prerequisites are for green transformation in the RA
is another question. The purpose of the analysis carried
out in the paper is to analyse those initiatives and
prerequisites and to highlight the problems.
Cryptocurrencies and Portfolio Performance. Does Cryptocurrency Help Improve the Portfolio Performance?
Authors: Wuthisatian Phuvadon
Published: May 2023

This paper investigates the performance of cryptocurrencies and market indices. Using the dynamic conditional correlation (DCC) model, the result shows that cryptocurrencies and market indices, contrary to much of the literature, tend to move in the same direction, resulting in little or no benefits in portfolio management. Dividing into the sub-sample period, cryptocurrencies have moved even more strongly with market indices during the recent period after the COVID-19 pandemic, indicating the possibility of no hedging benefit. This paper shows that inclusion of cryptocurrency in a portfolio increases the return as well as volatility, as the risk-adjusted return does not show any sign of improvement. A portfolio comprising the FTSE 100 Index seems to receive the greatest benefit of including cryptocurrencies as the risk-adjusted performance improves.
Hematological parameters of the blood of Cameroonian goats
Authors:   Ivanovo State Agricultural Academy named after D. K. Belyaev, Kletikova Lyudmila , Yakimenko Nina ,   Ivanovo State Agricultural Academy named after D. K. Belyaev, Bugaeva Anna ,   Ivanovo State Agricultural Academy named after D. K. Belyaev
Published: May 2023

Today, the products of the goat breeding industry are in demand in the con- sumer market of the country, because. differs in taste and dietary properties. The quality of products depends on the health of the animals, which can be assessed using a study of hematological parameters. The study included 6-month-old Cameroonian goats. Hemato- logical studies were performed using a hematological analyzer, blood smears were stained according to Romanovsky-Giemsa, leukogram was counted manually, blood indices were calculated according to generally accepted methods. As a result of the study, the content of erythrocytes was 18.52 × 1012/L, hemoglobin – 100.67 g/L, hematocrit – 28.87%, MCV – 15.57 fl., MCH – 5.33 pg., MCHC – 349 00 g/L. In the study of white blood, the concen- tration of leukocytes was 11.63×109/L, the leukogram contained stab neutrophils – 1.30%, segmented – 25.64; lymphocytes – 63.64; monocytes – 5.02; eosinophils – 4.03; basophils – 0.32%. The calculation of integral leukocyte indices showed that the leukocyte index of intoxication B.A. Flight – 0.37 arb. units, index of allergization T.V. Kobets – 3.54; adapta- tion index L.Kh. Harkavy – 2.48; lymphocytic index according to Shaganin – 2.36; nuclear shift index – 0.05, immunoreactivity index according to D.O. Ivanov – 13.48 conv. units The concentration of platelets in the blood was 342.33×109/L. According to the data obtained, it follows that goats have normochromic anemia and thrombocytopenia, the content of leu- kocytes, the percentage and leukocyte indices correspond to the type of animals, and reflect their age characteristics.