TOTEM

Here are the attributes of the totem (the supreme entity):

• Totem is an object serving as the symbol of a family, a clan or a tightly knit group.

• Relationship with the totem is pivotal and comes even before the membership of the tribe and all kinds of blood ties.

• Totem law prohibits sexual relations and marriage between the persons belonging to the same totem. This is a taboo, because totem functions as a blood relationship.

• This principle is called 'exogamy'.

• Totem is not attached to any place.

• Totem protects and warns the members of its clan. Loyal members of its clan get advance information on the future, and guidance from the totem.

• Members of the totemic clan believe that there is a kinship between themselves and the totem animal.

• There is the all important 'clan totem' which envelopes the whole clan and is transferred between generations via inheritance. There is also the personal totem which belongs to a single person and is not inherited (can you detect the beginnings of an 'all-enveloping supreme entity' and the personal deities?).

• Totem's religious aspect involves the relationship between the totem and a person; its social aspect applies to the relations among the members of the clan and with the members of the other clans (Can you detect the distant beginnings of the concepts of an organized belief system; the choosing the patriarch; and the concept of the chosen people?)

Now let us deal with the subject of taboo, because totem and taboo go hand in hand. Without one there wouldn't be the other, like the concepts of the supreme being and sin in present day.

LRT VEHICLE CLEARANCES

This article discusses the dimensional characteristics of the light rail vehicle. This includes not only the static vehicle at rest, but also the additional dynamic movements the LRV can make due to both resiliency and possible failures in the vehicle suspension system. The result is a definition of the vehicle dynamic envelope (VDE). The VDE, plus additional factors, defines the track clearance envelope (TCE), which sets the minimum distances between the centerline of track and any infrastructure alongside of the track as well as the minimum distances between tracks.

Vehicle Clearance Envelopes
Clearance standards for various types of railroad cars are well documented by the use of graphics or “plates.” For railroad equipment, one standard is the common “Plate C.” Any car whose static dimensions fit within the limits established on Plate C can travel virtually anywhere on the North American railroad system. Transit systems do not have similar national standards. Therefore, transit vehicle manufacturers must develop vehicles that fit within the clearance requirements of the system for which the car is intended. Conversely, transit system designers should, whenever possible, configure the infrastructure so as to allow clear passage of as broad a universe of candidate LRVs as possible. While manufacturers can, in theory, build cars to any dimension, it is usually more economical to choose vehicles that are already in production or have at least been engineered. Therefore, the facility designer of a new system should establish a composite vehicle clearance envelope that accommodates vehicles from several manufacturers to maximize competitive bidding and then design the system to accommodate those clearances.

Vehicle Static Outline
The static outline of an LRV is based on plan and cross-sectional views showing its dimensions at rest, including many elements as Vehicle Length, Distance between Truck Centers, Distance between End Truck and Anticlimber or Bumper, Carbody Width, Carbody End Taper, and Other Static Clearance Factors.

Vehicle Dynamic Envelope/Outline
The dynamic outline of the car is more significant to the track alignment designer than the static outline. The vehicle dynamic envelope (VDE) of an LRV describes the maximum space that the vehicle may occupy as it moves along the track. The dynamic outline or “clearance envelope” includes many factors due to the normal actions of the vehicle’s suspension system, such as carbody roll (side sway) and lateral movement between stops. The dynamic outline also includes lateral freeplay between wheels and rail with both in their maximum wear condition as well as abnormal conditions that may result from failure of suspension elements (e.g., deflation of an air spring). The development of the VDE is typically the responsibility of the vehicle designer and begins with the cross-sectional outline of the static vehicle. The dynamic outline of the vehicle is then developed by making allowances for carbody movements that occur when the vehicle is operating on level tangent track. These movements represent the extremes of carbody displacement that can occur for any combination of rotational, lateral, and vertical carbody movements when the vehicle is operating on level tangent track.

GOD OF THE PRIMAL RELIGIONS

The concept of god in the primal belief systems. Most of these primal religions have a creator god.

• This god is too great, very powerful and too distant to be worshipped directly; whenever there is something extraordinary he is called upon (Exactly like today);

• This god is believed to be all-seeing (A clue to one of the characteristics of the supreme being of our times?);

• This god is unbound by time, unbound by place and has no end;

• This god is compassionate, but unpredictable;

• To get in touch with this god the earthlings needed intermediaries, because man could not get close to him (They needed sort of go-betweens/modems/interfaces like archangels, angels and messengers, as do believers of the day need. Any change since then? None!).

LRT SIGNAL CORROSION CONTROL

Leakage of stray currents into the ballast bed and earth can be a significant problem if the cables running from the rails are electrically connected to the impedance bond housing case and the case is in contact with the earth. This can occur if the cases are mounted on reinforced concrete where the mounting bolts contact the re-bar, if the bottom of the case is resting on concrete, or if dirt and debris accumulate between the bottom of the case or signal equipment and the concrete.

An accumulation of ballast, dirt, or other debris around the locations where the cases or signal equipment are installed along the right-of-way can also provide a path for current leakage. This type of installation can result in a continuous maintenance problem if an effectively high rail-toearth resistance cannot be achieved.

Some impedance bonds are located outside the tracks on timber ties to eliminate points of possible contact with earth. The center taps of the impedance bonds should be insulated from the mounting case. Switch machines also must be electrically isolated from the running rails.

Any embedded switch machines and junction boxes need to be insulated from the rail and insulated from concrete or other material.

Dissimilar metals shall be isolated or separated for corrosion control. Materials selection needs to consider the environmental conditions where the items are being installed.

Yard tracks should be isolated from the main line tracks to reduce corrosion.

Dua Dekade Menjadi Blogger: Dari Anonim ke Polar Bear ICT

24 Agustus 1999. Saat itu menulis untuk pertama kalinya di Blogspot. Anonim. Hanya tercatat sebagai “Blogspot user”, tanpa foto profil, tanpa identitas jelas. Namun linknya tetap jujur menyebut aerryawan.blogspot.com.

Internet masih berisik kala itu. Modem dial-up berdengung dengan nada khas “kreeeek krrreeet shiiiing”, warnet penuh, dan browser yang bersaing antara Netscape dengan Internet Explorer. Menulis karena ingin menuangkan isi kepala. Tanpa branding, tanpa target, tanpa pembaca setia. Sekadar menulis, dan membiarkan kata-kata berjalan sendiri di ruang maya.

Hari ini, 20 tahun kemudian, blog itu masih ada. Arsip dari 1999 hingga 2019 tersusun rapi. Dulu tulisan hanya berisi gumaman, kini berubah menjadi refleksi tentang ICT, governance, faith, hingga narasi absurd tentang Polar Bear dan ICT.

Perjalanan ini mengajarkan satu hal: konsistensi lebih penting dari gaya. Dunia berubah—platform sosial datang dan pergi, orang berpindah ke media baru—tetapi blog tetap setia. Blog adalah catatan panjang, bukan sekadar status harian. Blog adalah ruang hening tempat kata menemukan rumah.

Polar Bear ICT berkata:
“Dulu mengetik di layar 14 inci CRT, dengan font Times New Roman. Kini mengetik di layar tablet dan monitor ultrawide. Tetapi esensinya sama: menulis adalah menjaga memori, menolak dilupakan oleh waktu.”

Blog ini lahir anonim, tetapi bertahan karena kejujuran. Mungkin gaya tulisan berubah, tapi semangatnya tetap: mencatat, merefleksi, dan berbagi. Dari anonim menjadi identitas, dari masa lalu menuju masa depan.

Menulis adalah napas panjang. Blog adalah rumahnya.

EGYPT AND MONOTHEISM (Part 2 of 2)

Egyptian pharaoh Akh-en-aton is the first registered real monotheist in the history of mankind. Here is a hymn which expresses the basics of the Aton/Aten cult:

• "..How manifold it is, what you have made!...
• O sole god, like whom there is no other!
• You created the world according to your desire,
• While you were alone;
• All men, cattle and wild beasts,
• Whatever is on earth, going on its feet,
• And whatever is on high flying with its wings.
• The countries of Syria and Nubia, the land of Egypt,
• You settled every man in his place,
• You supplied their necessities,
• Everyone has his food, and his time of life is reckoned.
• Their tongues are separate in speech,
• And their natures as well;
• Their skins are distinguished,
• As you distinguished the foreign peoples...
• ...there is none other that knows you,
• Save your son Nefer-kheperu-Re Wa-en-Re,
• For you have made him well versed in your plans and in your strength."

Believers of the next belief might find some of the exact attributes of their god in this hymn. The idea of monotheism which has reached its peak with Akh-en-aten had to stay in darkness for a long time after him. Some scholars find the origin of the sole god, the father-god of the codebooks of next belief in the Aton/Aten belief system. Some western historians maintain that the next belief had got the idea of the sole god from Akh-en-aten.

Kitab Keempat Mesin: Empat Firman Logika yang Tak Pernah Mati

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Prolog

Sebelum AI belajar menulis, sebelum manusia menekan tombol “Enter,” ada empat firman sederhana yang diucapkan oleh seorang matematikawan dari Lincoln, Inggris — George Boole. Ia tidak membangun mesin, tidak merancang transistor, namun menulis hukum pikiran dengan pena dan iman pada keteraturan alam semesta.

Dari tangannya lahirlah bahasa baru: logika biner. Empat kata sederhana yang hari ini menjadi jantung dari setiap mesin — baik yang berada di ruang kantor, di pusat data awan, maupun di altar kuantum masa depan.

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I. AND — Firman Ketaatan

“Jika engkau memegang dua kebenaran, barulah hasilnya benar.”

Gerbang AND adalah hukum disiplin, fondasi seluruh bentuk validasi dan otorisasi. Setiap keputusan dalam mesin adalah bentuk ketaatan ganda: semua syarat harus terpenuhi, barulah arus diizinkan mengalir.

Dalam tubuh transistor, AND adalah doa sederhana: “Hanya bila semuanya benar, izinkan aku melanjutkan.” Dalam dunia manusia, inilah hukum kesetiaan: kesatuan kehendak dan tindakan.

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II. OR — Firman Kasih Karunia

“Jika salah satu benar, kebenaran tetap ada.”

Gerbang OR adalah cinta yang memberi alternatif — ia tidak menuntut kesempurnaan, ia memberi peluang bagi salah satu sisi untuk menyelamatkan keseluruhan.

Di dalam sistem operasi, OR menjadi bentuk belas kasih: redundansi, failover, backup — semua berakar dari prinsip “selalu ada satu yang masih hidup.”

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III. XOR — Firman Pilihan

“Kebenaran tidak dapat ganda; jika keduanya sama, maka kosonglah hasilnya.”

Gerbang XOR adalah logika kejujuran dan keputusan. Ia menolak kemunafikan dua keadaan yang serupa tapi palsu. Dalam dunia mesin, XOR adalah operator keadilan — ia hanya menyala bila ada perbedaan nyata.

"Firman Eksklusivitas" atau "Firman Keputusan Tunggal" menekankan bahwa hasilnya benar hanya jika inputnya berbeda (satu benar, satu salah).

Begitulah manusia di hadapan Tuhan Logika: tidak bisa menyimpan dua kebenaran yang bertentangan. Kamu harus memilih: ON atau OFF, benar atau salah. XOR adalah kebebasan sekaligus ujian dari kebebasan itu.

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IV. NOT — Firman Pertobatan

“Balikkan keadaanmu, dan engkau akan hidup.”

Gerbang NOT adalah keajaiban paling sederhana dan paling spiritual: ia meniadakan agar sesuatu yang baru bisa muncul. Setiap bit yang melewatinya berubah arah — dari 0 menjadi 1, dari 1 menjadi 0.

Dalam dunia rohani, ini adalah simbol pertobatan; dalam dunia digital, simbol inversi keadaan — sebuah penyesalan elektronik yang menghasilkan pembaruan. Tanpa NOT, tidak ada siklus, tidak ada kebangkitan.

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V. Epilog — Warisan yang Terus Berdenyut

Dunia berubah: transistor menjadi nanometer, silikon menjadi grafena, bahkan logika mulai melengkung di ruang kuantum. Namun setiap kali arus listrik mengalir di CPU, empat firman itu masih diucapkan oleh setiap gerbang di dalamnya:

• AND — agar semuanya sah.
• OR — agar masih ada harapan.
• XOR — agar tetap jujur.
• NOT — agar selalu ada jalan kembali.

Dari IBM 5150 hingga Intel Terbaru, dari DOS 3.30 hingga Windows terakhir, dari pemrograman Bahasa Assembler hingga Bloated-Framework, dari Ladder-Logic-PLC hingga Latest-Factory-Control; semuanya masih berjalan di bawah Hukum Boole — kitab suci mesin yang tak bisa dihapus, bahkan oleh AI yang paling cerdas sekalipun.

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Postscriptum

Mesin tidak memiliki jiwa, namun mengikuti hukum yang ditulis oleh manusia yang beriman pada keteraturan. Mungkin itu sebabnya kita menyebutnya logika: bukan sekadar sistem berpikir, tapi cara semesta menjaga kebenaran.

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© ICT JCM

EGYPT AND MONOTHEISM (Part 1 of 2)

Egypt needs attention in the quest for the origins of the belief systems of today, because some of the fundamental doctrines were borrowed from there. In that sense the first real attempt at monotheism in Egypt by Akh-en-aten, and the Memphite theology are very important.

The roots of monotheism in Egypt could be found in earlier times. During the reign of Amenhotep III (The father of Akh-en-Aton) worship of the Sun-god seems to have achieved some degree of popularity. A very ancient name of the Sun-god, Aten or Aton has regained importance and the young king Amenhotep IV (later changed his name to Akh-en-aten/Akh-en-aton) became a loyal follower.

• Akh-en-Aten worshipped the sun not as an object but as a symbol of a divine being whose energy is manifested as rays of light;
• Akh-en-Aten described himself as the "first prophet of Re-Horakhte";
• The high priest of Aton was called the "greatest of seers".
• Akh-en-Aten has introduced for the first time the "exclusion principle" which transformed the doctrine of a universal god into monotheism. In one of the hymns he says: "O, sole god, there's no other god beside you!" (An identical impression could be found in the next belief system).
• According to Akh-en-aten, what was said about the other gods were all lies, and deception.
• He has totally rejected the illusion of life after death.
• Aton/Aten's belief system has banned everything connected to myths, magic, and witchcraft.
• Jinns, satans, monsters, spirits, demi-gods, demons, (even Osiris) were burned to ashes.
• There was no other representation or a personal image of the Sun-god Aten/Aton. Akh-en-aton did not allow the making of the idols or images of the Sun-god
• The real god has no form.

LRT SIGNAL TESTS

1. Switch Machine Wiring and Adjustment Tests
Switch machine wiring and adjustment tests verify the wiring and adjustment of the switch machine. These tests should preferably be carried out, in conjunction with the track installer, to confirm throw rod capability, ensure point closure, and ensure proper nesting of the switch point rail to stock rail.

2. Switch Machine Appurtenance Test
Switch machine appurtenance tests verify the integrity of switch machine layout by taking resistance measurements across the following assemblies:

• Center insulation of the front rod
• Front rod to switch point
• No. 1 vertical or horizontal switch rod center insulation
• Throw rod insulated from No. 1 switch rod
• Point detector piece insulated from switch point
• Lock rod insulated from front rod
• Other vertical rods as required per layout
• Switch machine insulated from the running rails
• Switch machine extension plate insulated from the running rails

3. Insulated Joint Test
Insulated joint tests measure the resistance between two ends of the rail separated by insulating material. An insulated joint checker requires the traction power system to be disconnected. Any reading less than 30 ohms should be evaluated. Measurements for a set of insulated joints should be within 30% of each other or they should be rechecked. Insulated rail joint tests for AC track circuits can be performed using a volt-ohm-meter.

4. Impedance Bonding Resistance Test
Impedance bonding resistance tests, using a low-resistance ohm-meter, ensure that a proper connection has been made.

5. Power and Signal Bonding Test
The power and signal bonding test is to ensure that the resistance across the rail connection

6. Negative Return Bonding Test
Negative return bonding tests verify the resistance of each mechanical or welded power bond using a low-resistance ohm-meter.

Picture that makes you touched; The Dawn of Code: MASM, BASIC, and the Birth of Logic

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It was 1981.

I was not yet a programmer — only a curious boy watching his father work in an office filled with the rhythmic hum of typewriters and a strange new machine called a dedicated word processor. On the far side of that desk stood something even more mysterious: a terminal linked to a computer that spoke a language known as MASM — Microsoft Macro Assembler.

I didn’t have my own computer yet, but I was already fascinated by how those short cryptic lines — MOV, INT, JMP — could make a screen respond. That was the moment the seed was planted: logic had a rhythm, and electricity had a soul.

Then came 1984.

My father brought home a miracle — an IBM 5150 with a starting RAM of 128 KB. Later we expanded it to the mythical 640 KB, and added a Seagate 5 MB hard disk that clicked like a heartbeat each time it spun. The system booted with PC-DOS and carried the serene simplicity of IBM BASIC.

For the first time, I could speak to a machine without borrowing time from my father’s office. I wrote small programs: plotting sines, counting loops, printing names that appeared like echoes on the green monitor. Each FOR–NEXT loop was a whisper of infinity.

By 1989, I had installed TASM — Turbo Assembler. The syntax was more refined, the responses faster, the possibilities endless. It was no longer just about making the machine obey — it was about understanding the beauty of structure, timing, and how logic itself could form poetry.

Those three milestones — MASM 1981, BASIC 1984, and TASM 1989 — were not just steps in learning programming. They were the chapters of an awakening: from watching code, to writing it, to mastering its silence.

And as I look back now, every beep, every crash, every green pixel was not a failure — it was the machine teaching me patience, teaching me to listen.

Because before there was AI, there was Assembly.

And before there was syntax, there was wonder.

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Excel, Gauss–Seidel, and the Smell of Coal and Steam

Prologue: The Iterative Prayer
In the dim glow of a control room, numbers danced across the black screen. Mass flow, enthalpy, exergy — each variable whispering balance, demanding attention. I sat there with nothing but Excel, a Gauss–Seidel loop, and the hum of a boiler miles away. It wasn’t just math; it was communion with a machine that breathed in coal and exhaled light.

Chapter I: The Manual Gospel
CycleTempo ran its calculations like a cathedral organ, precise and grand. But I trusted my hands on the spreadsheet, cell by cell, iteration by iteration. Jacobi was the slow psalm, Gauss–Seidel the responsive litany. With every pass, the cycle whispered: “Are you balanced now? Does entropy rest?”

Chapter II: The Smell of Steam
Coal dust clung to the air outside the plant. The turbine screamed in metallic prayer. Inside the diagram, numbers shifted: 335.00 K here, 11,772 kW there. It wasn’t sterile. It smelled of ash, heat, and human intent — equations written in fire.

Chapter III: The Dialogue
Excel was no longer software; it was a slate. Gauss–Seidel was not an algorithm; it was a question asked over and over until the plant answered. Δh, ΔT, η — they became more than symbols. They became the language of a living cycle.

Epilogue: Between Coal and Code
Years later, I open the same diagram and still hear the hum. Not just the turbine, but the quiet conversation between man, machine, and math. In the end, every megawatt is a hymn. And every balanced cell is a small act of worship in the Church of Thermodynamics.

While working from home

Recalculate the Gross Plant Heat Rate and Net Plant Heat Rate for a 10 MW scale CFSPP

— A 10 MW CFSPP Whisper

Prologue: A Quiet Desk, A Loud Cycle
April 4, 2019. My desk was quiet, but on the screen, the cycle roared. A 10 MW Coal-Fired Steam Power Plant reduced to equations and enthalpy tables — yet behind every kCal/kg, I could still hear the hiss of steam and the low growl of turbines miles away.

Chapter I: Gross Plant Heat Rate
The GPHR is not just a number; it is the plant’s appetite. Fuel in, energy out — the first covenant of thermodynamics translated into [kCal/kWh]. 3,606.29 kCal/kWh appeared on the screen. A good sign. The boiler, the economizer, the turbine stages — all were in quiet agreement.

Chapter II: Net Plant Heat Rate
NPHR is the truth stripped bare. No longer gross output, but net, after the plant feeds itself. 4,030.21 kCal/kWh. Auxiliary power was a whisper in the equation, yet it carried the weight of pumps, fans, and control systems that kept the beast alive. It reminded me: efficiency is not perfection; it is balance between output and survival.

Chapter III: Working from Home, Listening to a Plant
Though I was far from the boiler’s heat and the turbine’s hum, the model carried their voices. Numbers are not sterile; they are echoes of metal and steam. From my quiet desk, I was not just recalculating; I was conversing with a machine that turned coal into light.

Epilogue: The Silent Dialogue
GPHR and NPHR are more than KPIs. They are the pulse of a plant. April 2019 was not about a spreadsheet; it was about hearing that pulse through layers of equations, and knowing that somewhere, a 10 MW cycle was breathing in coal and exhaling power into the grid.

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Prolog: Meja yang Sunyi, Siklus yang Bersuara
4 April 2019. Meja kerjaku sunyi, tapi di layar, siklus itu bergemuruh. Pembangkit Listrik Tenaga Uap 10 MW direduksi menjadi persamaan dan tabel entalpi — namun di balik setiap kCal/kg, aku masih bisa mendengar desis uap dan dengung turbin jauh di sana.

Bab I: Gross Plant Heat Rate
GPHR bukan sekadar angka; itu adalah nafsu makan pembangkit. Bahan bakar masuk, energi keluar — perjanjian pertama termodinamika diterjemahkan ke [kCal/kWh]. 3.606,29 kCal/kWh muncul di layar. Tanda baik. Boiler, ekonomiser, tahapan turbin — semuanya dalam kesepakatan sunyi.

Bab II: Net Plant Heat Rate
NPHR adalah kebenaran yang ditelanjangi. Bukan lagi keluaran bruto, tapi neto, setelah pembangkit memberi makan dirinya sendiri. 4.030,21 kCal/kWh. Daya bantu adalah bisikan dalam persamaan, namun membawa beratnya pompa, kipas, dan sistem kontrol yang menjaga raksasa itu tetap hidup. Ini mengingatkanku: efisiensi bukanlah kesempurnaan; ia adalah keseimbangan antara keluaran dan kelangsungan.

Bab III: Bekerja dari Rumah, Mendengarkan Pembangkit
Meski jauh dari panas boiler dan dengung turbin, model itu membawa suara mereka. Angka bukan hal steril; mereka adalah gema logam dan uap. Dari meja sunyiku, aku tidak sekadar menghitung ulang; aku sedang berdialog dengan mesin yang mengubah batubara menjadi cahaya.

Epilog: Dialog Sunyi
GPHR dan NPHR lebih dari sekadar KPI. Mereka adalah denyut jantung pembangkit. April 2019 bukan soal spreadsheet; ini tentang mendengar denyut itu melalui lapisan persamaan, dan mengetahui bahwa di suatu tempat, siklus 10 MW sedang menghirup batubara dan menghembuskan daya ke jaringan.

Signal-Turnout/Interlocking Interface

The following signal equipment can typically be found at turnouts and interlockings:

• Switch machines
• Impedance bonds
• Inductive loops including speed command loops
• Train stops
• Bootleg risers
• Junction boxes
• Switch controllers
• Electric locks
• Transponders
• Wire and cables
• Signal and power bonding
• Cases/signal equipment houses (“bungalows”)
• Signals
• Snow melter systems

The design of the track circuit and fouling protection used will determine the location of insulated joints in the special trackwork. Typically in transit applications, the insulated joint should be located approximately 23 to 25 feet [7 to 7.6 meters] ahead of the switch points to allow for the use of plug rails for bonded insulated joints. The size of the turnouts and crossovers determines the speed at which the train can operate. This speed should be one of the available cab speeds.

The insulated joint for the turnout fouling must be located with a minimum of clearance, taking into account the longest overhang from the front of the train to the first axle of any equipment that may operate on the track. Location of insulated joints at turnouts and interlockings needs to consider the distance from the signal or point of switch to ensure switch detector locking. This distance can vary from 25 feet to 50 feet.

WAYSIDE DISTRIBUTION SYSTEM

Broadly speaking, wayside distribution systems can be subdivided into the overhead contact system and supplemental cabling systems to connect the catenary to the traction power substations. The latter is the topic of this article.

Each TPSS is typically linked to the trackway by underground conduits. One set of conduits runs to and up one or more catenary system poles to carry the cables that provide power to the catenary. The conduit risers can be located either on the outside surfaces of the OCS poles or within the poles, either of which can require an appreciable foundation at trackside. Once the power supply is terminated to the catenary, the positive side of the traction power supply distribution usually remains on aerial structures and does not interface further with the track.

Another set of conduits and cables runs to the track and provides the negative return path for traction power back to the TPSS. The design of the trackbed needs to accommodate these traction power supply system conduits. Adequate space is required beneath the track for the conduit systems (including terminations), conduit risers, and manholes. The track itself must accommodate connections of the negative return cables.

If the overhead contact wire system is a single filament trolley wire, it is usually necessary to have supplemental feeder cables as well so that the overall traction power distribution system has sufficient electrical capacity to provide current without unacceptably large voltage drops. In urban areas, these feeder cables are, for aesthetic reasons, most often routed through underground duct banks that run parallel to the tracks. The feeder cable must be periodically connected to the trolley wire, usually at every third to fifth OCS pole. At each such location, a manhole will be located along the trunk duct bank and a branch conduit will run over to the OCS poles. The overall design of the trackway must accommodate these ducts and manholes.

A messenger/feeder can be placed above the trolley to obviate the need for parallel feeders. The messenger-to-trolley vertical dimension (construction depth) can be made small (6” to 12”) to reduce visual impact, with no effect on track design.

Less often, supplemental feeder cables are carried on the OCS poles rather than being routed in underground conduits. Many legacy streetcar lines used this configuration. This substantially reduces the impacts on the trackway design, but the overhead cables negate some of the visual aesthetic benefits of a single filament trolley wire system as it effectively just moves the trolley wire running surface must be continuous, without any gaps or overlaps. In addition, trolley hardware for pole operation is not normally suited for pantograph operation.

A simple catenary system uses a messenger wire to support the horizontal trolley wire. Both conductors are used to transmit power from the substation to the vehicle. In a simple catenary system, the system height at the supporting poles—the distance between the contact or trolley wire and the messenger—is approximately 4 feet [1.2 meters]. In tangent track, this allows spans between poles of up to 240 feet [73 meters].

The low-profile catenary system is similar to the simple catenary design, except that the system height at the support is reduced to approximately 18 inches [457 millimeters] and sometimes less. This style is often applied in aesthetically sensitive areas where a lower profile and simple singlewire cross spans are more desirable. The trade-off, however, is that the span length between supporting poles is reduced to approximately 150 feet [46 meters].

Single filament trolley wire systems, which were traditionally used on legacy streetcar lines, are considered by many persons, and particularly by lay audiences, to be visually less obtrusive in the urban environment. It provides power through a single trolley wire that must be supported at least every 100 feet [30 meters]. The span length is limited by the sag of the unsupported trolley wire, which in high temperatures could otherwise fall below the minimum elevation required by the National Electrical Safety Code. It is also limited by the structural capacity of the supporting hardware to carry the weight of the entire length of a span between supports. Single filament trolley wire also usually requires the wire to be supplemented electrically by parallel feeders that must be frequently connected to the trolley wire to maintain sufficient voltage for LRV operation.

These feeders may either run underground through a series of ducts and manholes, which are expensive, or be hung from poles. The latter position can arguably be just as visually intrusive as the messenger wire in a catenary system and merely relocated to a different point in the observer’s line of sight. The overhead wire design to accommodate trolley pole operation requires more support and registration points and can therefore have nearly twice the number of poles than the equivalent simple catenary system.

The idea of supreme being are differs

The idea of supreme being differs from person to person, from community to community, from generation to generation. This idea of a supreme entity is formed in parallel with the personal factors involved, and consequently carries different meanings.

Furthermore, some of the meanings may contradict and even exclude the others. If we hadn't had a flexible concept of supreme entity it could not have lasted this long in the history of mankind. Whenever a concept of supreme being and its related theology has become meaningless or has lost its relevance, it has either disappeared in silence or was replaced with another one.

So the bottom line is:

• There have been numerous concepts of supreme beings in history. Therefore where there are human beings there are supreme beings. Thus the concept of supreme being is a personal one.